Bio

Clinical Focus


  • Thoracic Surgery
  • Cardiovascular Surgery

Academic Appointments


Professional Education


  • Residency:University of Virginia Medical Center (06/1988) VA
  • Fellowship:University of Pennsylvania Hospital (06/1990) PA
  • Medical Education:Duke University School of Medicine (06/1982) NC
  • Board Certification: Thoracic Surgery, American Board of Thoracic Surgery (1992)
  • Fellowship, University of Pennsylvania, Cardiothoracic Surgery, adult and pediatric
  • Residency, University of Virginia, General Surgery
  • MD, Duke University School of Medicine, Medicine

Research & Scholarship

Current Research and Scholarly Interests


Professional Interests: Pediatric cardiovascular surgery, surgery for adults with congenital heart disease

Teaching

2013-14 Courses


Publications

Journal Articles


  • Early complete repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals. Annals of thoracic surgery Watanabe, N., Mainwaring, R. D., Reddy, V. M., Palmon, M., Hanley, F. L. 2014; 97 (3): 909-915

    Abstract

    Pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals (PA/VSD/MAPCAs) is a complex and diverse form of congenital heart defect. Although most patients with PA/VSD/MAPCAs can wait until they are 3 to 6 months of age to undergo surgical reconstruction, there are three specific criteria that merit an earlier repair. These 3 criteria are (1) unremitting heart failure; (2) a ductus to one lung and MAPCAs to the other; and (3) hemitruncus to one lung and MAPCAs to the other. The purpose of this study was to evaluate our surgical experience with early complete repair of PA/VSD/MAPCAs.This was a retrospective review of patients undergoing complete repair of PA/VSD/MAPCAs within the first 60 days of life. Twenty-seven patients were identified in our database (2002 to 2013) who met these criteria. Fifteen had congestive heart failure, 9 had a ductus plus MAPCAs, and 3 had hemitruncus plus MAPCAs. The median age at surgery was 5 weeks.There was no operative mortality in this cohort of 27 patients. Hemodynamics at the conclusion of the complete repair demonstrated an average right ventricular peak systolic pressure of 32 ± 5 mm Hg and an average right ventricle to aortic pressure ratio of 0.36 ± 0.06. The median length of hospital stay was 26 days. There have been 2 subsequent mortalities (7%), with a median follow-up duration of 4 years. Eight of the 27 patients have subsequently undergone conduit replacements at our institution. The hemodynamics at the conclusion of the conduit change were statistically unchanged compared with the hemodynamics after complete repair.The data demonstrate that early complete repair of PA/VSD/MAPCAs can be accomplished with low mortality and excellent postoperative hemodynamics. These early hemodynamic results are maintained at medium-term follow-up. We conclude that early complete repair is an appropriate choice for this highly select subgroup of patients.

    View details for DOI 10.1016/j.athoracsur.2013.10.115

    View details for PubMedID 24480261

  • Innominate artery cannulation and antegrade cerebral perfusion for aortic arch reconstruction in infants and children. World journal for pediatric & congenital heart surgery Nasirov, T., Mainwaring, R. D., Reddy, V. M., Sleasman, J., Margetson, T., Hanley, F. L. 2013; 4 (4): 356-361

    Abstract

    Innominate artery cannulation has been widely adopted as a means to perform aortic arch reconstruction with continuous cerebral perfusion in the newborn. Although this technique has been subsequently utilized in infants and children, there is currently no data regarding the safety or efficacy in these older children. The purpose of this study was to review our experience with innominate artery cannulation for aortic arch reconstruction in patients beyond the neonatal period.This was a retrospective review of 42 infants and children who underwent aortic arch reconstruction using the technique of innominate artery cannulation with continuous cerebral perfusion. Of these procedures, 29 (69%) were primary arch reconstructions, while 13 (31%) were aortic arch reoperations. The median age at surgery was 8 months, and 22 patients underwent concomitant intracardiac repairs.There was no operative mortality in this cohort of 42 patients undergoing aortic arch reconstruction. There was also no overt evidence of neurologic injury. Specifically, none of the patients demonstrated a neurologic deficit, clinical seizure, or unexpected delay in regaining a normal state of consciousness. The median duration of antegrade cerebral perfusion was 34 minutes. The median duration of hospital stay was 11 days. No patient required reoperation on the aortic arch with a median of 45-month follow-up.Innominate artery cannulation is a safe and effective technique for aortic arch reconstruction in nonneonates. We conclude that antegrade cerebral perfusion is a useful technique for aortic arch reconstruction in this patient population.

    View details for DOI 10.1177/2150135113497767

    View details for PubMedID 24327627

  • Aortic valve disease in pulmonary atresia and major aortopulmonary collaterals. Annals of thoracic surgery Mainwaring, R. D., Dimeling, G., Punn, R., Hanley, F. L. 2013; 95 (6): 2122-2125

    Abstract

    Aortic valve disease in association with pulmonary atresia, ventricular septal defect, and major aortopulmonary collaterals (PA/VSD/MAPCAs) is an extremely rare combination of congenital heart defects. The presence of aortic stenosis or insufficiency or both imposes an additional physiologic burden that complicates the management of PA/VSD/MAPCAs. This report summarizes our experience with 7 patients who underwent surgical repair of this rare combination of defects.This was a retrospective review of patients who had both aortic valve disease and PA/VSD/MAPCAs. Four patients had predominantly aortic stenosis, 2 patients had aortic insufficiency, and 1 had mixed stenosis and insufficiency. Anatomically, this corresponded to a dysplastic trileaflet valve in 4, bicuspid valve in 2, and quadricuspid valve in 1.Four of the 7 patients underwent aortic valve surgery at the time of their first operation for PA/VSD/MAPCAs. The remaining 3 patients had aortic valve surgery at subsequent operations. All 7 patients are alive, with a median duration of follow-up of 3 years. One patient has required aortic valve replacement 2 years after repair of an insufficient bicuspid valve.This manuscript summarizes our experience with 7 patients who had the rare combination of aortic valve disease and PA/VSD/MAPCAs. Although aortic valve disease has been reported for other conotruncal defects, we believe this is the first report of its presence in association with PA/VSD/MAPCAs.

    View details for DOI 10.1016/j.athoracsur.2013.03.070

    View details for PubMedID 23643545

  • Surgical Reconstruction of Pulmonary Stenosis With Ventricular Septal Defect and Major Aortopulmonary Collaterals ANNALS OF THORACIC SURGERY Mainwaring, R. D., Punn, R., Reddy, V. M., Hanley, F. L. 2013; 95 (4): 1417-1421

    Abstract

    Pulmonary stenosis with ventricular septal defect and major aortopulmonary collaterals (PS/VSD/MAPCAs) is an extremely rare form of congenital heart defect. Although it has been assumed that PS/VSD/MAPCAs would be similar to pulmonary atresia (PA) with VSD/MAPCA, there are currently no data to support this conjecture. This study reviewed our surgical experience with reconstruction of PS/VSD/MAPCA.This was a retrospective review of 25 patients (14 boys, 11 girls) who were born with PS/VSD/MAPCA and underwent surgical reconstruction. Preoperative pulmonary angiography was used to define the central branch pulmonary arteries and MAPCA. Patients were a median age of 4 months at the first operation.There was one operative death (4%) in this cohort of 25 patients, and complete repair was achieved in the 24 survivors (96%). There were two distinct subgroups of patients: 11 demonstrated cyanosis in the neonatal timeframe and underwent an initial procedure to augment pulmonary blood flow (+PBF). The remaining 14 patients formed the second group (-PBF). The median age at the first operation was 0.8 months in the +PBF group and 5.2 months in the -PBF group (p<0.005). Complete repair was achieved in 91% of patients in the +PBF group and in 100% in the -PBF group; however, the average number of procedures to achieve complete repair was 2.8 in the +PBF group vs 1.0 in the -PBF group (p<0.005).Outcomes for PS/VSD/MAPCAs as a whole were excellent, with a low surgical mortality and high rate of complete repair. There were two identifiable subgroups with distinctive differences required in their surgical management. These results provide a prognostic outlook for patients with PS/VSD/MAPCAs that can be compared and contrasted with PA/VSD/MAPCAs.

    View details for DOI 10.1016/j.athoracsur.2013.01.007

    View details for Web of Science ID 000317150600039

    View details for PubMedID 23434256

  • Hemodynamic Assessment After Complete Repair of Pulmonary Atresia With Major Aortopulmonary Collaterals ANNALS OF THORACIC SURGERY Mainwaring, R. D., Reddy, V. M., Peng, L., Kuan, C., Palmon, M., Hanley, F. L. 2013; 95 (4): 1397-1402

    Abstract

    Pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals (PA/VSD/MAPCAs) is a complex form of congenital heart defect. There are limited data regarding late hemodynamics of patients after repair of PA/VSD/MAPCAs. This study evaluated the hemodynamics of patients who underwent complete repair of PA/VSD/MAPCSs and subsequently returned for a conduit change.This was a retrospective review of 80 children undergoing a right ventricle (RV)-to-pulmonary artery conduit replacement after complete repair of PA/VSD/MAPCAs. All patients underwent preoperative cardiac catheterization to define the cardiac physiology. Patients were an average age of 6.5±1.2 years, and the average interval between complete repair and conduit change was 4.5±1.1 years.The preoperative cardiac catheterization demonstrated an average RV right peak systolic pressure of 70±22 mm Hg and pulmonary artery pressure of 38±14 mm Hg. This pressure gradient of 32 mm Hg reflects the presence of conduit obstruction. After conduit change, the intraoperative RV systolic pressure was 34±8 mm Hg, similar to 36±9 mm Hg at the conclusion of the previous complete repair. The corresponding RV/aortic pressure ratios were 0.36±0.07 and 0.39±0.09, respectively.The data demonstrate that patients who underwent complete repair of PA/VSD/MAPCAs had nearly identical pulmonary artery pressures when they returned for conduit change some 4.5 years later. This finding indicates that the growth and development of the unifocalized pulmonary vascular bed is commensurate with visceral growth. We would hypothesize that complete repair, along with low RV pressures, will confer a long-term survival advantage.

    View details for DOI 10.1016/j.athoracsur.2012.12.066

    View details for Web of Science ID 000317150600036

    View details for PubMedID 23453744

  • Surgical reconstruction of peripheral pulmonary artery stenosis in Williams and Alagille syndromes JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY Monge, M. C., Mainwaring, R. D., Sheikh, A. Y., Punn, R., Reddy, V. M., Hanley, F. L. 2013; 145 (2): 476-481

    Abstract

    Peripheral pulmonary artery stenosis is a rare congenital heart defect frequently found in association with Williams and Alagille syndromes. Controversy exists regarding the optimal treatment of peripheral pulmonary artery stenosis, with most centers favoring catheter-based interventions. In contrast, we have preferentially used surgical reconstruction of peripheral pulmonary artery stenosis. The purpose of the present study was to review our experience with surgical reconstruction of peripheral pulmonary artery stenosis.We performed a retrospective review of patients who underwent surgical reconstruction of peripheral pulmonary artery stenosis. A total of 16 patients were identified: 7 had Williams syndrome, 6 had Alagille syndrome, and 3 had no identifiable syndrome. Detailed pulmonary angiography was performed in all patients to define stenoses at the main, branch, lobar, and segmental arterial levels. The mean preoperative right ventricular/left ventricular pressure ratio was 0.88 ± 0.07. The surgical approach was a median sternotomy with cardiopulmonary bypass. All peripheral stenoses were augmented with pulmonary artery homograft tissue. The median age at surgery was 14 months, and concomitant procedures were performed in 9 of the 16 patients.There was 1 operative mortality (6%). The mean right ventricular/left ventricular pressure ratio decreased to 0.40 ± 0.04 postoperatively (P < .005), representing a 55% reduction compared with the preoperative values. The patients were followed up for a median of 5 years. No late mortality occurred and reoperation was not required.The data have demonstrate that this comprehensive surgical approach to the treatment of peripheral pulmonary artery stenosis was associated with low early and no late mortality. Surgical reconstruction of the peripheral pulmonary artery stenosis resulted in a significant decrease in right ventricular pressure. We hypothesize that this reduction in right ventricular pressures will confer a long-term survival advantage for this cohort of patients.

    View details for DOI 10.1016/j.jtcvs.2012.09.102

    View details for Web of Science ID 000313634700030

    View details for PubMedID 23228407

  • Prevalence of Anomalous Coronary Arteries in Pulmonary Atresia with Ventricular Septal Defect and Major Aortopulmonary Collaterals. Journal of the American College of Cardiology Muralidaran, A., Mainwaring, R. D., Reddy, V. M., Hanley, F. L. 2013

    View details for PubMedID 23871887

  • Late Outcomes in Patients Undergoing Aortopulmonary Window for Pulmonary Atresia/Stenosis and Major Aortopulmonary Collaterals ANNALS OF THORACIC SURGERY Mainwaring, R. D., Reddy, V. M., Perry, S. B., Peng, L., Hanley, F. L. 2012; 94 (3): 842-849

    Abstract

    Pulmonary atresia with ventricular septal defect (PA/VSD) and major aortopulmonary collateral arteries (MAPCAs) is a complex form of congenital heart defect. One identifiable subset has small (<2.5 mm) intrapericardial branch pulmonary arteries that are (1) confluent, (2) have normal arborization, and (3) have dual-supplied collateral vessels. When this anatomy is associated with limited pulmonary blood flow, the patients are candidates for creation of an aortopulmonary window to stimulate growth of the pulmonary arteries. The purpose of this study was to review our experience with creation of an aortopulmonary window as the initial palliative procedure.This was a retrospective review of our surgical experience with 35 children undergoing aortopulmonary window creation from 2002 to 2011. Patients were identified by preoperative cardiac catheterization to define the cardiac and pulmonary artery anatomy.There was no mortality in 35 patients undergoing aortopulmonary window creation. These patients have subsequently undergone 78 cardiac procedures (with 2 operative mortalities). Eighteen of these patients have achieved complete repair, 4 patients in a second procedure, 6 patients in a third procedure, 5 patients in a fourth procedure, and 3 patients in a fifth procedure.The data demonstrate that patients can undergo creation of an aortopulmonary window with excellent early results. Few patients were amenable to complete repair at the second operation, and most required multiple reoperations to recruit sufficient arborization. We interpret these counterintuitive results to suggest that hypoplastic central pulmonary arteries and diminished pulmonary blood flow are markers for a less well developed pulmonary vascular bed.

    View details for DOI 10.1016/j.athoracsur.2012.03.061

    View details for Web of Science ID 000308138900031

    View details for PubMedID 22857982

  • Late Repair of the Native Pulmonary Valve in Patients With Pulmonary Insufficiency After Surgery for Tetralogy of Fallot ANNALS OF THORACIC SURGERY Mainwaring, R. D., Pirolli, T., Punn, R., Hanley, F. L. 2012; 93 (2): 677-679

    Abstract

    Pulmonary regurgitation developing late after tetralogy of Fallot repair is now recognized as a serious threat to the long-term welfare of these patients. This article summarizes our experience with 5 patients who underwent reoperations for treatment of severe pulmonary regurgitation after transannular patch repair of tetralogy of Fallot. In each case, the intraoperative findings revealed anatomy favorable for valve repair and enabled preservation of the native pulmonary valves.

    View details for DOI 10.1016/j.athoracsur.2011.09.016

    View details for Web of Science ID 000299540200069

    View details for PubMedID 22269747

  • Anomalous Aortic Origin of a Coronary Artery: Medium-Term Results After Surgical Repair in 50 Patients ANNALS OF THORACIC SURGERY Mainwaring, R. D., Reddy, V. M., Reinhartz, O., Petrossian, E., Macdonald, M., Nasirov, T., Miyake, C. Y., Hanley, F. L. 2011; 92 (2): 691-697

    Abstract

    Anomalous aortic origin of a coronary artery (AAOCA) is a rare congenital heart defect that has been associated with myocardial ischemia and sudden death. Controversies exist regarding the diagnosis, treatment, and long-term recommendations for patients with AAOCA. The purpose of this study is to evaluate the medium-term results of surgical repair for AAOCA.From January 1999 through August 2010, 50 patients underwent surgical repair of AAOCA. The median age at surgery was 14 years (range, 5 days to 47 years). Thirty-one patients had the right coronary originate from the left sinus of Valsalva, 17 had the left coronary originate from the right sinus, and 2 had an eccentric single coronary ostium. Twenty six of the 50 patients had symptoms of myocardial ischemia preoperatively, and 14 patients had associated congenital heart defects. Repair was accomplished by unroofing in 35, reimplantation in 6, and pulmonary artery translocation in 9.There was no operative mortality. The median time of follow-up has been 5.7 years. Two patients were lost to follow-up, and 1 patient required heart transplantation 1 year after AAOCA repair. In the remaining 47 postoperative patients, all have remained free of cardiac symptoms and no one has experienced a sudden death event.The surgical treatment of AAOCA is safe and appears to be highly effective in eliminating ischemic symptoms. These medium-term results are encouraging and suggest that many patients may be able to resume normal activities.

    View details for DOI 10.1016/j.athoracsur.2011.03.127

    View details for Web of Science ID 000293221000050

    View details for PubMedID 21718962

  • Congenital Anomalies of the Mitral Valve. In: Mavroudis C, and Backer CL, Eds. Pediatric Cardiac Surgery Fourth Edition, Wiley-Blackwell, Inc. Mainwaring RD, and Lamberti JJ. 2011
  • Surgical Results and Follow-up in Patients with Pulmonary Atresia and Multiple Aortopulmonary Collaterals in Association with Total Anomalous Pulmonary Venous Connection. Ann Thorac Surg Mainwaring RD, Reddy VM, Reinhartz O, Punn R, Tacy T, Hanley FL. 2011: 1756-60
  • Unusual Manifestations of Vascular Rings JOURNAL OF CARDIAC SURGERY Mainwaring, R. D., Jacobson, J. L., Reinhartz, O., Gates, R. L. 2010; 25 (1): 79-83

    Abstract

    Vascular rings are a relatively rare entity caused by abnormal development of the fetal aortic arches. Most patients with vascular rings present in infancy or early childhood with respiratory (inspiratory) symptoms. The treatment of patients with symptomatic vascular rings is generally straight-forward, focusing on surgical division of the ring. The majority of patients are "cured" by this simple procedure. However, a small percentage of patients do not follow this typical course. The purpose of this manuscript is to review and discuss three patients who demonstrated unusual manifestations of vascular rings. Two patients required reoperation after double aortic arch repair and one had successful treatment of an aberrant right subclavian artery.

    View details for DOI 10.1111/j.1540-8191.2009.00947.x

    View details for Web of Science ID 000273164700023

    View details for PubMedID 19874418

  • Double-Orifice Tricuspid Valve in Association with Complete Atrioventricular Septal Defect PEDIATRIC CARDIOLOGY Mainwaring, R. D., Reddy, V. M., Wright, S. B. 2009; 30 (4): 564-565

    View details for DOI 10.1007/s00246-009-9432-3

    View details for Web of Science ID 000266167600038

    View details for PubMedID 19357908

  • Octreotide for Management of Chylothorax following Bidirectional Glenn in a Three-Month-Old Infant JOURNAL OF CARDIAC SURGERY Wright, S. B., Mainwaring, R. D. 2009; 24 (2): 216-218

    Abstract

    Chylothorax developing after open heart surgery for congenital heart defects can be a challenging problem. Established therapies are not always efficacious. This report summarizes our experience using octreotide as an adjunct in the management of an intractable chylous effusion.The patient described underwent a bilateral bidirectional cavopulmonary anastomosis at 3 months of age. Postoperatively, the patient demonstrated significant quantities of milky fluid drainage from the right pleural chest tube. Initial management included diuretics, afterload reduction, and a non-fat diet. These maneuvers appeared to be effective. However, the patient experienced a recurrence of the effusion requiring re-admission to the hospital and re-insertion of a right pleural chest tube. Given the recalcitrant nature of the effusion, an infusion of octreotide was begun.An octreotide infusion was begun at 1 mcg/kg/hr and gradually increased to 3 mcg/kg/hr. Chest tube drainage diminished allowing chest tube removal 13 days later. The octreotide infusion was weaned off over the subsequent 10 days without any further effusion problems.Octreotide may be a useful adjunct in the management of intractable chylous effusions following congenital heart surgery.

    View details for DOI 10.1111/j.1540-8191.2008.00803.x

    View details for Web of Science ID 000263694600033

    View details for PubMedID 19267835

  • Outcome Analysis for a Small, Start-up Congenital Heart Surgery Program JOURNAL OF CARDIAC SURGERY Mainwaring, R. D., Reddy, V. M., Reinhartz, O., Lamberti, J. J., Jacobson, J. G., Jimenez, D. L., Hanley, F. L. 2008; 23 (6): 622-626

    Abstract

    There will be a continuing need to start new congenital heart surgery programs to serve communities experiencing significant population growth. However, small congenital heart programs frequently underperform their larger counterparts. This study summarizes the clinical outcome data for the first 42 months of a small, start-up congenital heart surgery program. Clinical outcomes were summarized from the start of the program in September 2003 through March 2007. Risk adjustment analysis was performed using the risk adjustment in congenital heart surgery (Rachs-1) risk adjustment model and Society of Thoracic Surgeons (STS) congenital database. Three hundred eighty-six operations have been performed during this time period, including 47 newborns, 96 infants, 217 children/adolescents, and 26 adults (greater than 18 years). There have been two operative mortalities (0.5%). Assigning these cases to the Rachs-1 categories, there were 64 level I, 188 level II, 90 level III, 12 level IV cases, with 32 "others." The predicted mortality for the 354 categorized cases calculates to be 17.4 (Rachs-1) and 10.2 (STS). The data demonstrate that a start-up program with a relatively modest surgical volume can achieve satisfactory clinical results. This model has relied upon careful case selection and direct, senior-level surgeon involvement through an affiliation with a university-based program. These results suggest that a small congenital heart surgery program can be successfully started if the circumstances are carefully controlled.

    View details for DOI 10.1111/j.1540-8191.2008.00675.x

    View details for Web of Science ID 000260499400007

    View details for PubMedID 19016985

  • Brain natriuretic peptide levels before and after ventricular septal defect repair ANNALS OF THORACIC SURGERY Mainwaring, R. D., Parise, C., Wright, S. B., Juris, A. L., Achtel, R. A., Fallah, H. 2007; 84 (6): 2066-2069

    Abstract

    Brain natriuretic peptide is a relatively recently discovered circulating mediator that has been correlated with the degree of heart failure in adults. This study evaluated the preoperative and postoperative brain natriuretic peptide levels in infants and children undergoing ventricular septal defect repair.The study enrolled 18 infants and children (ages 2 months to 15.6 years) scheduled for surgical repair of their ventricular septal defects. Brain natriuretic peptide levels were drawn preoperatively and then postoperatively at 1, 24, 48, and 72 hours. The amount of shunt (the ratio of pulmonary blood flow [Q(p)]/systemic blood flow [Q(s)]) through the ventricular septal defect was determined by saturation levels performed in the catheterization laboratory or intraoperatively.The preoperative brain natriuretic peptide levels (pg/mL) averaged 78 +/- 57, and the postoperative levels were 168 +/- 241 at 1 hour, 418 +/- 330 at 24 hours, 405 +/- 364 at 48 hours, and 391 +/- 397 at 72 hours. These differences were significant for each postoperative time point compared with preoperative values. Preoperative brain natriuretic peptide and the Q(p)/Q(s) were significantly correlated (age-adjusted R(2) = 0.33, p < 0.001).Brain natriuretic peptide levels have a close correlation with the physiologic volume load caused by ventricular septal defects. The preoperative brain natriuretic peptide levels were also found to be predictive for the postoperative time course of brain natriuretic peptide level changes. These results suggest that brain natriuretic peptide levels may be a useful clinical marker in infants and children with ventricular septal defects.

    View details for DOI 10.1016/j.athoracsur.2007.07.021

    View details for Web of Science ID 000251176300037

    View details for PubMedID 18036937

  • Pentalogy of Cantrell: a rare congenital abnormality. JAAPA : official journal of the American Academy of Physician Assistants Dinice, J., Mainwaring, R. D. 2007; 20 (11): 26-27

    View details for PubMedID 18035760

  • The extracardiac conduit Fontan operation using minimal approach extracorporeal circulation: Early and midterm outcomes JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY Petrossian, E., Reddy, V. M., Collins, K. K., Culbertson, C. B., MacDonald, M. J., Lamberti, J. J., Reinhartz, O., Mainwaring, R. D., Francis, P. D., Malhotra, S. P., Gremmels, D. B., Suleman, S., Hanley, F. L. 2006; 132 (5): 1054-1063

    Abstract

    Our approach to the extracardiac conduit Fontan operation has evolved over time from full-pump, to partial-pump, to completely off-pump. This study is designed to report our overall experience with the extracardiac conduit Fontan operation and to evaluate the evolution in bypass technique on postoperative outcomes.From September 1992 to April 2005, 285 patients, median age 4.5 years (1.4-44 years), median weight 16 kg (9.4-94 kg), underwent a primary extracardiac conduit Fontan procedure. Early and late outcomes were analyzed for the entire cohort and for 2 patient groups depending on whether an oxygenator was used in the bypass circuit (166 patients; 58%) or not (119 patients; 42%).Early failure (including death and takedown) occurred in 7 patients (2.5%). Prevalence of new early postoperative sinus node dysfunction necessitating a permanent pacemaker was 0.4%, and that of new tachyarrhythmias necessitating discharge home on a regimen of antiarrhythmia medications was 2.5%. Ten-year actuarial freedom from Fontan failure, new sinus node dysfunction necessitating a permanent pacemaker, and reoperation for conduit thrombosis or stenosis was 90%, 96%, and 98%, respectively. Fenestration rate was lower (P = .001) in the no-oxygenator group (8%) than in the oxygenator group (25%). Patients in the no-oxygenator group had lower intraoperative Fontan pressure (12.0 +/- 2.3 vs 13.5 +/- 2.4 mm Hg, P < .001), common atrial pressure (4.6 +/- 1.8 vs 5.3 +/- 1.8 mm Hg, P = .003), and transpulmonary gradient (7.5 +/- 2.1 vs 8.3 +/- 2.2 mm Hg, P = .013) than did the oxygenator group.The extracardiac conduit Fontan operation coupled with minimal use of extracorporeal circulation is associated with favorable intraoperative hemodynamics, low fenestration rate, minimal risk of thrombosis or stenosis, and minimal early and late rhythm disturbance.

    View details for DOI 10.1016/j.jtcvs.2006.05.066

    View details for Web of Science ID 000241497500009

    View details for PubMedID 17059923

  • Unifocalization of major aortopulmonary collaterals in single-ventricle patients ANNALS OF THORACIC SURGERY Reinhartz, O., Reddy, V. M., Petrossian, E., Suleman, S., Mainwaring, R. D., Rosenthal, D. N., Feinstein, J. A., Gulati, R., Hanley, F. L. 2006; 82 (3): 934-939

    Abstract

    Unifocalization of major aortopulmonary collateral arteries (MAPCAs) in pulmonary atresia with ventricular septal defect and intracardiac repair has become the standard of care. However, there are no reports addressing unifocalization of MAPCAs in single-ventricle patients. It is unknown whether their pulmonary vascular bed can be reconstructed and low enough pulmonary vascular resistance achieved to allow for superior or total cavopulmonary connections.We reviewed data on all patients with functional single ventricles and unifocalization procedures of MAPCAs. From 1997 to 2005, 14 consecutive children with various single-ventricle anatomies were operated on.Patients had a median of three surgical procedures (range, 1 to 5). Two patients had absent, all others diminutive central pulmonary arteries, with an average of 3.5 +/- 1.2 MAPCAs. Seven patients (50%) had bidirectional Glenn procedures, and 3 of these had Fontan procedures. Median postoperative pulmonary artery pressures measured 12.5 mm Hg (Glenn) and 14 mm Hg (Fontan), respectively. Six patients are alive today (46%), with 1 patient lost to follow-up. Three patients died early and 3 late after initial unifocalization to shunts. One other patient survived unifocalization, but was not considered a candidate for a Glenn procedure and died after high-risk two-ventricle repair. Another patient with right-ventricle-dependent coronary circulation died of sepsis late after Glenn.In selected patients with functional single ventricles and MAPCAs, the pulmonary vascular bed can be reconstructed sufficiently to allow for cavopulmonary connections. Venous flow to the pulmonary vasculature decreases cardiac volume load and is likely to increase life expectancy and quality of life for these patients.

    View details for DOI 10.1016/j.athoracsur.2006.03.063

    View details for Web of Science ID 000239996300025

    View details for PubMedID 16928512

  • Atrial Septal Defects. In: Kaiser LR, Kron IL, and Spray TL, Eds. Mastery of Cardiothoracic Surgery Second Edition. Mainwaring RD, and Lamberti JJ. 2006: 739-749
  • The Lexington physicians of General Robert E. Lee SOUTHERN MEDICAL JOURNAL Mainwaring, R. D., Riley, H. D. 2005; 98 (8): 800-804

    Abstract

    General Robert E. Lee has been interpreted by history as one of the most intriguing personalities of the American Civil War era. In more recent years, there has been much speculation regarding General Lee's health during the war and the possible influence this had on his decision making and performance. Lee's personal letters during and after the war provide some documentation about his health condition, albeit through the eyes of a lay person. The history that was recorded by his personal physicians in Lexington, Virginia provides invaluable insights into his medical history. This manuscript focuses on the lives of these two physicians, Drs. Howard Barton and Robert Madison, and their interactions with their famous patient.

    View details for Web of Science ID 000231579600010

    View details for PubMedID 16144175

  • Supplementation of thyroid hormone in children undergoing cardiac surgery CARDIOLOGY IN THE YOUNG Mainwaring, R. D., Nelson, J. C. 2002; 12 (3): 211-217

    Abstract

    Triiodothyronine has been introduced as a promising new supplement for patients undergoing open-heart surgery. This manuscript will review the existing literature regarding supplementation with triiodothyronine in children. Infants and children undergoing cardiac surgery experience a profound decrease in levels of free and total triiodothyronine. These decreases are of sufficient magnitude to effect cardiac function. Supplementation with triiodothyronine has been shown to enhance myocardial performance, improve recovery of circulating levels of triiodothyronine, and to result in an increase in mixed venous oxygen saturation. As encouraging as these results are, there is no definitive study which demonstrates that triiodothyronine improves clinical outcome in children. Thus, while triiodothyronine appears to have promise as a supplement for children undergoing open-heart surgery, more studies are needed to establish the efficacy of such therapy scientifically.

    View details for Web of Science ID 000176685800002

    View details for PubMedID 12365165

  • Pharmacokinetic evaluation of triiodothyronine supplementation in children after modified Fontan procedure CIRCULATION Mainwaring, R. D., Capparelli, E., Schell, K., Acosta, M., Nelson, J. C. 2000; 101 (12): 1423-1429

    Abstract

    Triiodothyronine (T(3)) supplementation may be a useful adjunct in the management of patients after cardiopulmonary bypass. Limited data are available regarding the use and pharmacokinetics of T(3) in children. The present study was performed to evaluate T(3) pharmacokinetics in a cohort of children undergoing the modified Fontan procedure.A total of 28 patients were enrolled in this randomized, prospective study. The patients were divided into 4 groups: 1 group received a placebo and 3 groups received intravenous T(3) at dosages of 0.4, 0.6, and 0.8 microg/kg, respectively. All 28 patients survived their operative procedures. Two patients developed low cardiac output, and 3 patients had pleural effusions. The median length of hospital stay was 7 days. The mean free T(3) level was 316+/-67 pg/dL after then administration of a placebo. Patients who received T(3) had mean peak free T(3) levels of 972+/-88, 1351+/-299, and 1869+/-281 pg/dL for the dosages of 0.4, 0.6, and 0.8 microg/kg, respectively. The calculated half-life of T(3) was 7 hours.The half-life of intravenous T(3) in children is approximately one-third of that reported for adults. These results provide a framework for studying the efficacy of T(3) supplementation in children undergoing open-heart surgery.

    View details for Web of Science ID 000086143700020

    View details for PubMedID 10736287

  • Effect of accessory pulmonary blood flow on survival after the bidirectional Glenn procedure. Circulation Mainwaring, R. D., Lamberti, J. J., Uzark, K., Spicer, R. L., Cocalis, M. W., Moore, J. W. 1999; 100 (19): II151-6

    Abstract

    The bidirectional Glenn procedure (BDG) is used in the staged surgical management of patients with a functional single ventricle. Controversy exists regarding whether accessory pulmonary blood flow (APBF) should be left at the time of BDG to augment systemic saturation or be eliminated to reduce volume load of the ventricle. The present study was a retrospective review of patients undergoing BDG that was conducted to assess the influence of APBF on survival rates.From 1986 through 1998, 149 patients have undergone BDG at our institution. Ninety-three patients had elimination of all sources of APBF, whereas 56 patients had either a shunt or a patent right ventricular outflow tract intentionally left in place to augment the pulmonary blood flow provided by the BDG. The operative mortality rate was 2.2% without APBF and 5.4% with APBF. The late mortality rate was 4.4% without APBF and 15.1% with APBF. Actuarial analysis demonstrates a divergence of the Kaplan-Meier curves in favor of patients in whom APBF was eliminated (P<0.02). One hundred seven patients have subsequently undergone completion of their Fontan operation, so the actuarial analysis includes the operative risk of this second operation.The results suggest that the elimination of APBF at the time of BDG may confer a long-term advantage for patients with a functional single ventricle.

    View details for PubMedID 10567295

  • Effect of accessory pulmonary blood flow on survival after the bidirectional Glenn procedure CIRCULATION Mainwaring, R. D., Lamberti, J. J., Uzark, K., Spicer, R. L., Cocalis, M. W., Moore, J. W. 1999; 100 (19): 151-156
  • Extracardiac conduit fontan for children with heterotaxy and functionally single ventricle CARDIOLOGY IN THE YOUNG Mainwaring, R. D., Lamberti, J. J. 1998; 8 (4): 479-485

    Abstract

    Children with functionally single ventricle in the setting of visceral heterotaxy (isomerism) may present a surgical challenge at the time of Fontan completion because of anomalies of systemic and pulmonary venous drainage. We have used an extracardiac conduit in this population to direct inferior caval venous blood to the pulmonary arteries. Over the past five years, nine children with heterotaxy and a functionally single ventricle underwent correction by placement of an extracardiac synthetic (Gore-Tex) conduit. All patients had previously undergone a bidirectional Glenn procedure. Age and weight at the time of insertion of the extracardiac conduit were 26 +/- 15 months, and 11 +/- 2 kilograms, respectively.Of the nine children, six had an uneventful recovery. One developed elevated venous pressures and required a 'fenestration procedure'. Two patients developed pleural effusions. Median length of stay in hospital was 10 days. All children are alive and well, with follow-up of 19 +/- 16 months. There have been no thromboembolic complications.The extracardiac conduit has worked well in our experience for the completion of the Fontan circulation in children with functionally single ventricle in the setting of visceral heterotaxy.

    View details for Web of Science ID 000077254300013

    View details for PubMedID 9855102

  • Complement activation and cytokine generation after modified Fontan procedure ANNALS OF THORACIC SURGERY Mainwaring, R. D., Lamberti, J. J., Hugli, T. E. 1998; 65 (6): 1715-1720

    Abstract

    The modified Fontan procedure separates the systemic and pulmonary circulations in patients born with a functional single ventricle. Delayed recovery is frequently observed after this procedure. It was our hypothesis that complement activation or cytokine generation may contribute to the pathophysiology of this problem.We measured activated complement C3, thromboxane B2, interleukin-6, and tumor necrosis factor-alpha levels by immunoassay in 16 patients undergoing Fontan procedure. Patient plasma samples were obtained preoperatively, on initiation of cardiopulmonary bypass, after administration of protamine, and 1, 4, 8, and 24 hours postoperatively.There was no early or late mortality in this cohort of patients. Low cardiac output developed in 3 of 16 patients, and pleural effusions developed in 5. The median length of hospital stay was 9 days. Activated complement C3 levels increased from a baseline of 1,486 +/- 564 to 4,600 +/- 454 ng/mL after cardiopulmonary bypass and administration of protamine, and returned to baseline by 24 hours. The level of interleukin-6 increased from 42 +/- 32 to 176 +/- 22 pg/mL and at 24 hours remained elevated at 71 +/- 15 pg/mL. Neither thromboxane B2 nor tumor necrosis factor-alpha levels increased significantly.The data demonstrate threefold to four-fold increases in activated complement C3 and interleukin-6, indicating that both humoral and cellular systems are affected. It is our conclusion that complement and cytokine activation may contribute to the delayed recovery observed after Fontan procedure.

    View details for Web of Science ID 000074274100050

    View details for PubMedID 9647087

  • Neurodevelopmental outcomes in children with Fontan repair of functional single ventricle PEDIATRICS Uzark, K., Lincoln, A., Lamberti, J. J., Mainwaring, R. D., Spicer, R. L., Moore, J. W. 1998; 101 (4): 630-633

    Abstract

    The purpose of this study was to assess the neurodevelopmental status of children after Fontan repair of functional single ventricle and to examine the relationship between cognitive function and selected patient characteristics.Neurodevelopmental tests including the Stanford-Binet Intelligence (IQ) scale and the Developmental Test of Visual Motor Integration (VMI) were administered to 32 children (26 months to 16 years of age) with complex single ventricle. The mean and distribution of IQ and VMI scores were compared with population norms. The relationship between test scores and patient characteristics was examined utilizing analysis of variance and correlational methods.The majority of children had intellectual function within the normal range (mean, 97.5 +/- 12.1). Below average VMI scores were found in 21.4% of children. There were no significant correlations between intellectual function or visual motor integration ability and preoperative oxygen saturation or age at Fontan. Children who had deep hypothermic circulatory arrest during a prior Norwood procedure tended to have a lower IQ score.Intellectual development in children with Fontan repair of complex heart defects is essentially within the normal range. Visual motor integration deficits may be more prevalent in these children. In our population, the duration and degree of preoperative hypoxemia had no apparent effect on cognitive function.

    View details for Web of Science ID 000072843200011

    View details for PubMedID 9521946

  • Mid- to long-term results of the two-stage approach for type B interrupted aortic arch and ventricular septal defect ANNALS OF THORACIC SURGERY Mainwaring, R. D., Lamberti, J. J. 1997; 64 (6): 1782-1785

    Abstract

    Type B interrupted aortic arch with ventricular septal defect is a complex congenital heart defect that may have associated left ventricular outflow tract obstruction. Surgical management has evolved from a two-stage approach to the currently favored single-stage approach. The following data summarize our experience with the two-stage approach over a 15-year period.Between 1980 and 1995, 27 consecutive patients with type B interrupted aortic arch and ventricular septal defect underwent surgical management using the two-stage approach. There were 15 girls and 12 boys; 21 patients had the DiGeorge syndrome.Stage I was performed at a median age of 4 days. Twenty-six (96%) of 27 patients survived first-stage palliation. One patient survived stage I palliation but died before undergoing stage II. Twenty-five patients underwent second-stage repair at a median age of 6 weeks (range, 1 to 46 weeks). There were 2 early deaths and 1 late death. Actuarial analysis demonstrates 1- and 5-year survival rates of 85% and 81%, respectively. Twenty-two survivors have been followed up for an average of 8 +/- 2 years. Freedom from reoperation for arch graft enlargement has been 86% at 3 years and 55% at 5 years. Freedom from reoperation for left ventricular outflow tract obstruction has been 82% at both 3 and 5 years.The two-stage approach can achieve good mid- to long-term palliation of patients with type B interrupted aortic arch and ventricular septal defect. These results should provide a reference from which to gauge the long-term success of the single-stage approach.

    View details for Web of Science ID 000071469400051

    View details for PubMedID 9436572

  • Tetralogy of Fallot repair results in activation of the renin-angiotensin-aldosterone system EUROPEAN HEART JOURNAL Mainwaring, R. D., Lamberti, J. J., Moore, J. W., Billman, G. F., Carter, T. L., Nelson, J. C. 1996; 17 (9): 1421-1425

    Abstract

    Fluid retention is a common problem following transannular patch repair of tetralogy of Fallot. The present study was undertaken to evaluate whether humoral substances may contribute to this process. Patients undergoing tetralogy of Fallot repair using a transannular patch technique were compared to patients undergoing simple ventricular septal defect repair. Hormone levels were determined by radioimmunoassay. Fluid retention was defined as pleural effusions persisting beyond 5 days. The data demonstrate that patients undergoing tetralogy of Fallot repair had elevated levels of anti-diuretic hormone, renin, angiotensin II, and aldosterone as compared to a group with ventricular septal defect. The elevation in hormone levels in the tetralogy of Fallot group was principally accounted for by those who developed effusions postoperatively. These results suggest that activation of the renin angiotensin-aldosterone system may be one of the contributing factors to fluid retention following tetralogy of Fallot repair.

    View details for Web of Science ID A1996VG27600022

    View details for PubMedID 8880028

  • Aortopulmonary collateral vessels and prolonged pleural effusions after modified Fontan procedures AMERICAN HEART JOURNAL Spicer, R. L., Uzark, K. C., Moore, J. W., Mainwaring, R. D., Lamberti, J. J. 1996; 131 (6): 1164-1168

    Abstract

    Pleural effusions after the modified Fontan procedure are unpredictable, increase morbidity, and prolong hospital stay. To assess the relation between preoperative characteristics and postoperative pleural drainage, we performed a retrospective study of 71 patients who underwent Fontan procedures. Analyses revealed no significant relation between duration of effusion and age at Fontan, preoperative oxygen saturation, pulmonary artery pressure, ventricular end-diastolic pressure, type of Fontan, or prior cavopulmonary anastomosis. Patients with significant aortopulmonary collateral vessels evidenced by angiographic opacification of the pulmonary arteries or veins had more prolonged pleural drainage. The duration of the pleural drainage was significantly less in patients who had aortopulmonary collateral occlusion.

    View details for Web of Science ID A1996UP98200017

    View details for PubMedID 8644596

  • PERCUTANEOUS USE OF STENTS TO CORRECT PULMONARY-ARTERY STENOSIS IN YOUNG-CHILDREN AFTER CAVOPULMONARY ANASTOMOSIS AMERICAN HEART JOURNAL Moore, J. W., Spicer, R. L., Perry, J. C., Mathewson, J. W., Kirkpatrick, S. E., George, L., Uzark, K., MAINWARING, R. L., Lamberti, J. J. 1995; 130 (6): 1245-1249

    Abstract

    Pulmonary artery distortion is a risk factor among candidates for the Fontan procedure. In 57 patients evaluated by catheterization after successful cavopulmonary anastomosis, 8 had proximal left pulmonary artery (LPA) stenosis, either discrete (4 patients) or long segment (4 patients). Median age was 27 months (range 19 to 60 months). Median weight was 11.4 kg (range 9.1 to 20.0). Mean diameter at LPA stenosis was 4.4 +/- 0.4. Proximal right pulmonary artery mean diameter was 10.4 +/- 1.0 mm. After angiographic and hemodynamic assessment, short 11F sheaths were placed in the right internal jugular (6 patients) or subclavian veins (2 patients). Pulmonary artery angioplasty and stent placement were performed. LPA stenoses were enlarged using 10 Palmaz stents dilated to 10 mm (7 patients) or to 12 mm (3 patients). Poststent angiograms showed that narrowest LPA dimensions were significantly enlarged to 9.9 mm +/- 1.0 mm, p < 001). There were no complications. Follow-up studies (catheterizations in 4 patients, echocardiograms in 8 patients) were performed 4 to 9 months after stent implantation. No restenosis was observed. Five patients had completion of their Fontan procedures; three patients are pending Fontan completion. This study demonstrates the efficacy and safety of the percutaneous use of Palmaz stents to correct pulmonary artery stenosis in young children after cavopulmonary anastomosis.

    View details for Web of Science ID A1995TH12600014

    View details for PubMedID 7484776

  • Bidirectional Glenn. Is accessory pulmonary blood flow good or bad? Circulation Mainwaring, R. D., Lamberti, J. J., Uzark, K., Spicer, R. L. 1995; 92 (9): II294-7

    Abstract

    The bidirectional Glenn (BDG) is frequently used in the staged surgical management of single ventricle patients. Controversy exists whether accessory pulmonary blood flow (APBF) sources should be left at the time of the BDG to augment systemic saturation or should be eliminated to reduce volume load of the ventricle. The present study was a retrospective review to assess the influence of APBF on outcome after the BDG.Ninety-two patients have undergone BDG at our institute during the interval from 1986 through 1994. At the time of BDG, 40 patients had either a systemic-to-pulmonary artery shunt or patent right ventricular outflow tract as an additional source of pulmonary blood flow. Fifty-two patients had elimination of APBF. There were three operative deaths (two with and one without APBF) and four procedures (two in each group) that failed and required subsequent revision. Thus, there were 85 patients who underwent successful operation. Effusions (defined as chest tube drainage exceeding 7 days' duration) occurred in 8 of 85 patients; this complication was seen in 7 of 36 patients (19%) with APBF and 1 of 49 patients (2%) without APBF (P < .05). There were 11 deaths, including 6 patients (17%) with APBF, 2 patients (4%) without APBF, and 3 of the patients (75%) who had a failed BDG.The data suggest that morbidity and mortality are lower in patients in whom APBF is eliminated at the time of the BDG.

    View details for PubMedID 7586426

  • RENIN, ANGIOTENSIN-II, AND THE DEVELOPMENT OF EFFUSIONS FOLLOWING BIDIRECTIONAL GLENN AND FONTAN PROCEDURES JOURNAL OF CARDIAC SURGERY Mainwaring, R. D., Lamberti, J. J., Carter, T. L., Moore, J. W., Nelson, J. C. 1995; 10 (2): 111-118

    Abstract

    Pleural effusions are a troublesome complication following bidirectional Glenn and Fontan procedures. It was our hypothesis that effusions may be related to alterations in hormones that regulate fluid homeostasis. We made serial determinations (by radioimmunoassay) of antidiuretic hormone, cortisol, aldosterone, angiotensin II, and renin in patients undergoing bidirectional Glenn (n = 16) and Fontan procedures (n = 24). There were six patients who developed effusions following surgery. These patients had a different endocrinological pattern characterized by persistent elevation in renin (28 +/- 9 vs 9 +/- 5 ng/mL per hour, p < 0.01) and angiotensin II (110 +/- 33 vs 33 +/- 14 ng/L, p < 0.01) on the fifth postoperative day as compared to patients who did not develop effusions. These data demonstrate that patients who develop effusions following bidirectional Glenn and Fontan procedures have activation of their renin-angiotensin system.

    View details for Web of Science ID A1995QR19800003

    View details for PubMedID 7772874

  • Tracheoesophageal Compressive Syndromes of Vascular Origin: Rings and Slings. In: Baue AE, Ed. Glenn?s Thoracic and Cardiovascular Surgery Sixth Edition, Stamford, CA. Appleton and Lange. Mainwaring RD, and Lamberti JJ. 1995: 1095-1103
  • Palliation of the Univentricular Heart. Heart Surgery. Lamberti JJ, Uzark K, Mainwaring RD, Moore JE, Spicer RL. 1995: 139-149
  • SUPPRESSION OF THE PITUITARY-THYROID AXIS AFTER CARDIOPULMONARY BYPASS IN THE NEONATE ANNALS OF THORACIC SURGERY Mainwaring, R. D., Lamberti, J. J., Billman, G. F., Nelson, J. C. 1994; 58 (4): 1078-1082

    Abstract

    Thyroid hormone has numerous effects on cardiovascular function in the adult. The present study was undertaken to evaluate the effects of cardiopulmonary bypass and deep hypothermia on thyroid function in the neonate. Ten newborns were studied preoperatively and postoperatively. The total and free triiodothyronine, total and free thyroxine, thyroid-stimulating hormone, and thyroglobulin levels were measured by immunoassays. The data demonstrated a transient rise in the free thyroxine level associated with and followed by significant reductions in the free and total triiodothyronine, total thyroxine, thyroid-stimulating hormone, and thyroglobulin levels in the early postoperative period. By the fifth postoperative day, the free and total triiodothyronine and total thyroxine levels were returning toward the preoperative levels under the influence of an elevated thyroid-stimulating hormone level. These results suggest that the combination of cardiopulmonary bypass and deep hypothermia can result in a transient suppression of the pituitary-thyroid axis in the neonate.

    View details for Web of Science ID A1994PL57200028

    View details for PubMedID 7944754

  • REDUCTION IN TRIIODOTHYRONINE LEVELS FOLLOWING MODIFIED FONTAN PROCEDURE JOURNAL OF CARDIAC SURGERY Mainwaring, R. D., Lamberti, J. J., Carter, T. L., Nelson, J. C. 1994; 9 (3): 322-331

    Abstract

    Diminished cardiac function is a common manifestation following the modified Fontan procedure. Since thyroid hormone has important effects on cardiovascular function, the present study was undertaken to evaluate changes in thyroid hormone levels following this operation. A control group consisting of children undergoing open heart procedures other than a Fontan procedure was also evaluated. Serum total and free triiodothyronine (T3), total and free thyroxine (T4), thyroid stimulating hormone (TSH), and thyroglobulin were measured by immunoassays. The Fontan group demonstrated an initial increase in free T4, while free T3, total T3, total T4, TSH, and thyroglobulin were reduced. Over the subsequent days, free T4 decreased to below the preoperative value. By the fifth and eighth postoperative days, free T3, total T3, free T4, and total T4 remained reduced, while TSH and thyroglobulin began increasing toward the preoperative levels. The control group also demonstrated decreases in free T3 and TSH. However, these values had returned to baseline by the fifth postoperative day. The results indicate that children undergoing open heart surgery have suppression of the pituitary-thyroid axis, and that this is prolonged in patients undergoing Fontan procedure. The decreased levels of T3 following Fontan procedure may have adverse effects on the recovery of patients undergoing this operation.

    View details for Web of Science ID A1994NN76200006

    View details for PubMedID 8054727

  • The Bidirectional Glenn: Palliation of the Univentricular Heart. In: Karp RD, Laks H, and Wechsler AS, Eds. Advances in Cardiac Surgery, Vol. 5, St. Louis Mosby-Year Book, Inc. Mainwaring RD, Lamberti JJ, Uzark K. 1994: 115-140
  • The bidirectional Glenn procedure: palliation of the univentricular heart. Advances in cardiac surgery Mainwaring, R. D., Lamberti, J. J., Uzark, K. 1994; 5: 115-140

    View details for PubMedID 7509702

  • Congenital Anomalies of the Mitral Valve. In: Mavroudis C, and Backer CL, Eds. Pediatric Cardiac Surgery Second Edition, St. Louis Mosby- Year Book, Inc. Lamberti JJ, and Mainwaring RD. 1994: 459-473
  • MANAGEMENT OF SYSTEMIC ATRIOVENTRICULAR VALVE REGURGITATION IN INFANTS AND CHILDREN JOURNAL OF CARDIAC SURGERY Lamberti, J. J., Mainwaring, R. D., George, L., Oury, J. H. 1993; 8 (6): 612-621

    Abstract

    Since September 1979, 53 patients have required operation for systemic atrioventricular valve regurgitation at Children's Hospital and Health Center of San Diego. (Primary repairs of atrioventricular canal defects are excluded from this report.) Diagnoses include single ventricle, cardiomyopathy, congenital mitral insufficiency , Marfan's disease, rheumatic heart disease, and a history of prior repair of atrioventricular canal defect. Ages ranged from 4 months to 19 years; median age is 5 years. In 31 patients, the atrioventricular valve could be repaired. In 24 patients, the valve was replaced (including two patients previously repaired). There were four operative deaths, all in the valve replacement group: three following valve replacement, and one following emergency thrombectomy. Two early failures in the repair group required valve replacement. Techniques for repair included leaflet resection, commissural annuloplasty, ring annuloplasty, and chordal shortening. Follow-up reveals good-to-excellent status in 38 patients. There were seven late deaths: six following valve replacement (one death valve related). Current surgical technique permits repair of the systemic atrioventricular valve in many infants and children requiring operation for regurgitation. The long-term results of valve repair are good to excellent. Repair avoids the morbidity and mortality of valve replacement, e.g., anticoagulation, fixed orifice size, and catastrophic mechanical valve malfunction.

    View details for Web of Science ID A1993MJ30200001

    View details for PubMedID 8286865

  • PULMONARY ATRESIA WITH INTACT VENTRICULAR SEPTUM - SURGICAL APPROACH BASED ON VENTRICULAR SIZE AND CORONARY ANATOMY JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY Mainwaring, R. D., Lamberti, J. J. 1993; 106 (4): 733-738

    Abstract

    Pulmonary atresia with intact ventricular septum has continued to have a high surgical mortality. This may relate to the nonuniformity of the anomaly. We have developed a management algorithm based on the right ventricular size and coronary anatomy. Patients with a well-developed ventricle and normal coronary arteries have undergone right ventricular outflow procedures. The adequacy of their right ventricles is subsequently evaluated; some patients are candidates for a four-chamber repair, whereas others are candidates for a Fontan procedure. Patients with severe hypoplasia of the right ventricle frequently have extensive ventriculo-coronary connections, and for these patients we have developed the technique of right ventricular obliteration. Over the past 7 years, we have treated 20 patients with pulmonary atresia with intact ventricular septum. Fourteen of the 20 patients underwent outflow tract procedures, with no operative mortality. There were two late deaths in this group. Six patients had hypoplasia of the ventricle with ventriculo-coronary connections and underwent right ventricular obliteration. There was one operative death and one late death in the group. Overall, 95% survived the neonatal period, and 80% were still alive at the time this article was written with an average follow-up of 32 months. We conclude that pulmonary atresia with intact ventricular septum can be successfully managed with the use of an algorithm based on ventricular size and coronary anatomy.

    View details for Web of Science ID A1993MA73300022

    View details for PubMedID 8412270

  • Bioprosthetic Valves in Children: Results. Heart Surgery. Lamberti JJ, and Mainwaring RD. 1993: 91-103
  • Palliation of the Univentricular Heart. Heart Surgery. Lamberti JJ, Uzark K, Mainwaring RD, Spicer RL. 1993: 153-160
  • THE INUTERO LEFT-VENTRICLE OF THE FETAL SHEEP - THE EFFECTS OF ISOPRENALINE JOURNAL OF PHYSIOLOGY-LONDON Anderson, P. A., FAIR, E. C., KILLAM, A. P., Nassar, R., Mainwaring, R. D., Rosemond, R. L., WHYTE, L. M. 1990; 430: 441-452

    Abstract

    1. Isoprenaline was infused into in utero fetal lambs to examine the effect of this beta-adrenoceptor agonist on left ventricular stroke volume and left ventricular output and test the generally held assumption that the fetal ventricle is markedly limited in its ability to increase ventricular output. 2. Seven in utero lambs (121-133 days of gestation) were instrumented with left ventricular dimension transducers, an ascending aortic electromagnetic flow transducer, a brachiocephalic arterial catheter and electrocardiographic and atrial pacing electrodes. 3. On the day of study, 5-8 days following surgery and 129-137 days of gestation, each lamb received infusions of isoprenaline, via the superior vena cava or left atrium, at rates which ranged from 0.005-0.5 microgram kg-1 min-1. 4. Heart rate and left ventricular stroke volume, output and end-diastolic and end-systolic dimensions were measured under control conditions and during various levels of isoprenaline infusion, with and without controlling heart rate. 5. Analysis of variance was done using the mean cell model. Least-square means and standard errors of the least-square means are reported. F ratios were calculated from type III sums-of-squares; P less than 0.05 was considered significant. 6. The mean heart rate increased with isoprenaline (P less than 0.0001) from a mean control level of 169 +/- 8 to 281 +/- 9 beats min-1 (+/- S.E.M.). 7. Mean left ventricular end-diastolic and end-systolic minor axis dimensions decreased significantly with isoprenaline from 16.7 +/- 0.1 mm (control) to 15.7 +/- 0.2 mm (P less than 0.0004) and from 11.7 +/- 0.1 mm (control) to 10.4 +/- 0.2 mm (P less than 0.0001) respectively. When heart rate was controlled with atrial pacing, mean end-diastolic dimension increased significantly at the higher isoprenaline doses from 14.6 +/- 0.1 mm (control) to 15.3 +/- 0.2 mm (control) (P = 0.0002), while mean end-systolic dimension fell significantly from 10.9 +/- 0.1 to 10.5 +/- 0.1 mm (P less than 0.003). Inasmuch as stroke volume increased, the increase in end-diastolic dimension and the fall in end-systolic dimension indicate an increase in venous return to the left ventricle. 8. During spontaneous rhythm, isoprenaline increased stroke volume from 2.45 +/- 0.06 ml (control) to 2.63 +/- 0.09 ml, not statistically significant. When heart rate was controlled, stroke volume increased with isoprenaline dose from 1.68 +/- 0.06 ml (control) to 2.40 +/- 0.08 ml (P less than 0.0001).(ABSTRACT TRUNCATED AT 400 WORDS)

    View details for Web of Science ID A1990EH23500024

    View details for PubMedID 2086769

  • INUTERO RIGHT VENTRICULAR OUTPUT IN THE FETAL LAMB - THE EFFECT OF HEART-RATE JOURNAL OF PHYSIOLOGY-LONDON Anderson, P. A., KILLAM, A. P., Mainwaring, R. D., Oakeley, A. E. 1987; 387: 297-316

    Abstract

    1. The effect of heart rate on right ventricular output was examined in six lambs during a period extending from 126 to 139 days of gestation. The fetuses had been surgically instrumented at least four days previously with a main pulmonary artery flow probe, right ventricular dimension transducers and left and right atrial pacing electrodes. 2. During spontaneous variations in heart rate, rate was correlated positively with right ventricular output (P less than 0.0001) and end-diastolic dimension (P less than 0.0001) among the lambs considered as a group, but no significant effect of rate on stroke volume was found. When individual responses were examined, output increased significantly with rate in sixteen out of seventeen observations. 3. With left atrial pacing, heart rate did not affect output. With right atrial pacing, rate correlated negatively with output (P less than 0.0001). With pacing from either site, rate correlated negatively with end-diastolic dimension (P less than 0.0001) and stroke volume (P less than 0.0001). 4. The introduction of a longer period interval during each pacing rate inhibited the rate-related decrease in dimension and allowed the ventricle to fill to the same end-diastolic dimension. The systole following these longer intervals had a greater stroke volume than did the preceding systoles with smaller end-diastolic dimension. The faster the preceding paced rate, the greater was the increase in stroke volume (P less than 0.001). 5. Right ventricular dimensions and volumes were measured in vitro, and the relationship was found to be linear using regression analysis. 6. This study demonstrates that experimentally induced variations in heart rate produce changes in end-diastolic volume and contractility which prominently affect right ventricular stroke volume. As a consequence, rate has, over a broad range, either no significant effect on output or a negative one. With spontaneous variations in rate, additional changes in contractility and venous return occur which affect stroke volume and end-diastolic volume and enhance right ventricular output. These relationships are similar to those in the adult heart, and demonstrate the absence of a maturational change in the effects of rate on ventricular function from the fetus to the adult.

    View details for Web of Science ID A1987H570000017

    View details for PubMedID 3656174

  • THE EFFECT OF HEART-RATE ON INUTERO LEFT-VENTRICULAR OUTPUT IN THE FETAL SHEEP JOURNAL OF PHYSIOLOGY-LONDON Anderson, P. A., GLICK, K. L., KILLAM, A. P., Mainwaring, R. D. 1986; 372: 557-573

    Abstract

    The effect of heart rate on left ventricular output was examined in seven fetal lambs at ages of 128 to 140 gestational days. The fetuses had been surgically instrumented at least 4 days previously with an ascending aortic flow probe, left ventricular dimension transducers, and left and right atrial pacing electrodes. Natural variations in heart rate of the lambs taken as a group correlated positively with left ventricular output, and negatively with ventricular end-diastolic dimension and stroke volume (P less than 0.0001). Rate did not affect output with right atrial pacing. With left atrial pacing, it correlated negatively with output (P less than 0.0001). At both pacing sites, rate correlated negatively with end-diastolic dimension and stroke volume (P less than 0.0001). The introduction of a longer interval during each pacing rate circumvented the rate-related changes in dimension and allowed the ventricle to fill to the same end-diastolic dimension. The systole at the end of the longer interval had a greater stroke volume than the preceding systoles. The faster the preceding paced rate, the greater was the stroke volume (P less than 0.0001). This study demonstrates that experimentally induced variations in heart rate produce changes in end-diastolic volume and contractility which prominently affect stroke volume. Over a broad range of rates, however, the effect of rate on left ventricular output is either negative or absent. With naturally occurring rate changes, there are additional changes in contractility and venous return which affect stroke volume. These combine to produce a positive relation between heart rate and left ventricular output. These effects of heart rate on output are qualitatively similar to those described for the adult animal.

    View details for Web of Science ID A1986A551000033

    View details for PubMedID 3723419

  • THE ROLE OF ADENOSINE IN THE REGULATION OF CORONARY BLOOD-FLOW IN NEWBORN LAMBS SURGERY Mainwaring, R. D., MENTZER, R. M., Ely, S. W., Rubio, R., Berne, R. M. 1985; 98 (3): 540-546

    Abstract

    Adenosine is a metabolic vasodilator of the coronary vessels in the adult. Whether it plays a similar role in the regulation of coronary blood flow (CBF) in the newborn is not known. We evaluated changes in adenosine release during periods of decreased oxygen supply (hypoxia) and increased oxygen demand (dobutamine infusions). In anesthetized open-chest lambs (age 1 to 8 days), aortic and coronary sinus adenosine concentrations, circumflex CBF, and myocardial oxygen consumption (MVO2) were measured. Adenosine was assayed by high-performance liquid chromatography, and the release of adenosine was calculated as the product of the aortic-coronary sinus plasma level difference and CBF in milliliters per minute per 100 gm myocardial tissue. Control values were obtained when the lambs were ventilated with 60% oxygen. In the first series of experiments, hypoxemia resulted in an increase in CBF from 120 +/- 5 to 171 +/- 8 ml/min/100 gm (p less than 0.01). This was associated with sixfold increase in adenosine release. In a second set of experiments the intravenous infusion of dobutamine resulted in parallel increases in MVO2 and CBF. Concomitantly, adenosine release increased by fivefold. There were significant linear relationships between MVO2 and CBF (r = 0.96; p less than 0.01), MVO2 and adenosine release (r = 0.69; p less than 0.002), and adenosine release and CBF (r = 0.71; p less than 0.002). These data support the hypothesis that adenosine may play an important role in the regulation of CBF in the newborn lamb.

    View details for Web of Science ID A1985AQH1400022

    View details for PubMedID 4035574

Conference Proceedings


  • Surgical outcomes for patients with pulmonary atresia/major aortopulmonary collaterals and Alagille syndrome Mainwaring, R. D., Sheikh, A. Y., Punn, R., Reddy, V. M., Hanley, F. L. OXFORD UNIV PRESS INC. 2012: 235-241

    Abstract

    Pulmonary atresia with major aortopulmonary collateral arteries (PA/MAPCAs) is a complex congenital heart defect that has undergone significant advances in treatment over the past 15 years. A small subset of patients with PA/MAPCAs have associated Alagille syndrome, which can have an adverse impact on many other organ systems. The purpose of this study was to review our institutional outcomes for the surgical patients with PA/MAPCAs and Alagille syndrome.This was a retrospective review of patients with PA/MAPCA's and Alagille who underwent surgical reconstruction from November 2001 to August 2011. Fifteen patients were identified in our data base. Thirteen had pulmonary atresia with ventricular septal defect (PA/VSD) and two had pulmonary atresia with intact ventricular septum (PA-IVS).There has been no early or late mortality in this cohort of 15 patients with PA/MAPCA' and Alagille syndrome. The patients have undergone a total of 38 cardiac surgical procedures. Ten of the 13 patients with PA/VSD have achieved complete repair, including unifocalization, a right ventricle to pulmonary artery conduit and closure of all intra-cardiac shunts. The three unrepaired patients with PA/VSD remain potential candidates for eventual complete repair, while the two patients with PA-IVS remain viable candidates for a single ventricle pathway. The patients in this series have also undergone 12 major non-cardiac procedures.The data demonstrate that surgical reconstruction of PA/MAPCAs can be successfully achieved in patients with Alagille syndrome. The longer-term prognosis remains guarded on the basis of the multi-organ system involvement of Alagille syndrome.

    View details for DOI 10.1093/ejcts/ezr310

    View details for Web of Science ID 000306365600013

    View details for PubMedID 22402453

  • Surgical Reconstruction of Tracheal Stenosis in Conjunction With Congenital Heart Defects Mainwaring, R. D., Shillingford, M., Davies, R., Koltai, P., Navaratnam, M., Reddy, V. M., Hanley, F. L. ELSEVIER SCIENCE INC. 2012: 1266-1273

    Abstract

    Surgical reconstruction is the primary method of treating airway obstruction in children. Tracheal stenosis is frequently associated with congenital heart defects, which may further complicate the overall management strategy. The purpose of this study was to review our experience with surgical reconstruction of airway obstruction in conjunction with congenital heart defects.This was a retrospective review of our surgical experience with tracheal stenosis from February 2003 to August 2011. Twenty-seven patients were identified in our database. Six patients had isolated, congenital tracheal stenosis, and 21 had tracheal stenosis in association with congenital heart defects. There were two identifiable subgroups. Thirteen patients had airway stenoses identified concurrently with congenital heart defects and underwent combined repair. The second group comprised 8 patients who had previous correction of their congenital heart defects and experienced delayed presentation of tracheal (n = 6) or bronchial (n = 2) obstruction.The median age at surgery was 9 months. There were 2 postoperative deaths, both in children with single ventricle. The median duration of follow-up for the entire cohort of 25 surviving patients was 4 years. None of the patients have required reoperations on the trachea; 5 have had minor reinterventions.The data demonstrate that tracheal obstruction is frequently found in conjunction with congenital heart defects. Nearly one third of our patients had delayed presentation of airway obstruction that was identified subsequent to previous congenital heart defect repair. Tracheal reconstructive techniques were effective regardless of the cause of the airway obstruction.

    View details for DOI 10.1016/j.athoracsur.2011.12.063

    View details for Web of Science ID 000302120200049

    View details for PubMedID 22381444

  • Triiodothyronine Supplementation in Infants and Children Undergoing Cardiopulmonary Bypass (TRICC) A Multicenter Placebo-Controlled Randomized Trial: Age Analysis Portman, M. A., Slee, A., Olson, A. K., Cohen, G., Karl, T., Tong, E., Hastings, L., Patel, H., Reinhartz, O., Mott, A. R., Mainwaring, R., Linam, J., Danzi, S. LIPPINCOTT WILLIAMS & WILKINS. 2010: S224-S233

    Abstract

    Triiodothyronine levels decrease in infants and children after cardiopulmonary bypass. We tested the primary hypothesis that triiodothyronine (T3) repletion is safe in this population and produces improvements in postoperative clinical outcome.The TRICC study was a prospective, multicenter, double-blind, randomized, placebo-controlled trial in children younger than 2 years old undergoing heart surgery with cardiopulmonary bypass. Enrollment was stratified by surgical diagnosis. Time to extubation (TTE) was the primary outcome. Patients received intravenous T3 as Triostat (n=98) or placebo (n=95), and data were analyzed using Cox proportional hazards. Overall, TTE was similar between groups. There were no differences in adverse event rates, including arrhythmia. Prespecified analyses showed a significant interaction between age and treatment (P=0.0012). For patients younger than 5 months, the hazard ratio (chance of extubation) for Triostat was 1.72. (P=0.0216). Placebo median TTE was 98 hours with 95% confidence interval (CI) of 71 to 142 compared to Triostat TTE at 55 hours with CI of 44 to 92. TTE shortening corresponded to a reduction in inotropic agent use and improvement in cardiac function. For children 5 months of age, or older, Triostat produced a significant delay in median TTE: 16 hours (CI, 7-22) for placebo and 20 hours (CI, 16-45) for Triostat and (hazard ratio, 0.60; P=0.0220).T3 supplementation is safe. Analyses using age stratification indicate that T3 supplementation provides clinical advantages in patients younger than 5 months and no benefit for those older than 5 months. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00027417.

    View details for DOI 10.1161/CIRCULATIONAHA.109.926394

    View details for Web of Science ID 000282294800032

    View details for PubMedID 20837917

  • Factors influencing perioperative morbidity during palliation of the univentricular heart Lamberti, J. J., Mainwaring, R. D., Spicer, R. L., Uzark, K. C., Moore, J. W. ELSEVIER SCIENCE INC. 1995: S550-S553

    Abstract

    The modified Fontan procedure has become the treatment of choice for patients born with a univentricular heart. Although the operative mortality has steadily decreased in recent years, the hospital stay is still prolonged in many patients due to fluid retention and pleural effusions.We retrospectively analyzed subsets of patients undergoing the bidirectional cavopulmonary shunt (BDCPS) and modified Fontan procedure in an attempt to define factors influencing operative mortality and morbidity.Multivariate analysis of 64 patients undergoing BDCPS revealed that age 6 months or less, concomitant operation, mean pulmonary pressure of 15 mm Hg or less, and mean pulmonary artery ratio of 1.8:1 or less were not statistically significant indicators of risk. Abnormal pulmonary artery architecture was a significant predictor of early and late death (p < or = 0.01). Retrospective analysis of 71 patients undergoing the modified Fontan procedure revealed no significant relationship between duration of pleural effusions and age at operation, preoperative oxygen saturation, pulmonary artery pressure, ventricular end-diastolic pressure, or prior BDCPS: Patients with important aortopulmonary collateral vessels defined by angiography had prolonged pleural drainage. Selective use of the total extracardiac conduit and the fenestrated Fontan resulted in low overall mortality with no statistical differences between subsets of patients undergoing different modifications of the Fontan procedure.These data indicate that the operative risk for BDCPS or modified Fontan procedure is quite low if a procedure appropriate for the patient is selected. Abnormal pulmonary artery architecture is an important risk factor for death after the BDCPS: Aortopulmonary collateral vessels are associated with fluid retention and pleural effusions after a modified Fontan procedure. Important aortopulmonary collateral vessels should be occluded before or during the modified Fontan procedure.

    View details for Web of Science ID A1995TW27300018

    View details for PubMedID 8604933

  • BIDIRECTIONAL GLENN - IS ACCESSORY PULMONARY BLOOD-FLOW GOOD OR BAD Mainwaring, R. D., Lamberti, J. J., Uzark, K., Spicer, R. L. LIPPINCOTT WILLIAMS & WILKINS. 1995: 294-297
  • DAMUS-KAYE-STANSEL PROCEDURE - MIDTERM FOLLOW-UP AND TECHNICAL CONSIDERATIONS Carter, T. L., Mainwaring, R. D., Lamberti, J. J. ELSEVIER SCIENCE INC. 1994: 1603-1608

    Abstract

    The Damus-Kaye-Stansel operation is useful in the management of complex congenital heart defects. We reviewed our experience with 23 patients who underwent a Damus-Kaye-Stansel procedure. The anastomotic technique was individualized depending on the anatomy. The aortic and pulmonary artery incisions were carried into the sinuses of Valsalva in 9 patients, the aorta was transected in 11 patients, and a patch was used to augment the anastomosis in 13 patients. Concurrent procedures included a Fontan operation (n = 9, mortality = 0), right ventricle-pulmonary artery conduit (n = 5, mortality = 0), bidirectional Glenn procedure (n = 6, mortality = 1), and central aortopulmonary shunt (n = 3, mortality = 2; emergency = 1). Survival is 87% with a median follow-up of 7 years (range, 2 months to 9.2 years). Four patients underwent late revision of the Damus-Kaye-Stansel connection. All survivors are asymptomatic. We conclude that the Damus-Kaye-Stansel connection provides excellent midterm results when the proximal anastomosis is adapted to the anatomy of the patient.

    View details for Web of Science ID A1994PU98600010

    View details for PubMedID 7979722

  • COMPARISON OF THE HORMONAL RESPONSE AFTER BIDIRECTIONAL GLENN AND FONTAN PROCEDURES Mainwaring, R. D., Lamberti, J. J., Moore, J. W., Billman, G. F., Nelson, J. C. ELSEVIER SCIENCE INC. 1994: 59-64

    Abstract

    Fluid retention is a frequent complication after the bidirectional Glenn and Fontan procedures. It was our hypothesis that this fluid retention may have a hormonal basis. To test this hypothesis, we made serial determinations of antidiuretic hormone, cortisol, aldosterone, angiotensin, and renin before and after operation in patients undergoing a bidirectional Glenn (n = 15) or Fontan (n = 18) procedure. Patients undergoing a bidirectional Glenn procedure had elevations in antidiuretic hormone, cortisol, and aldosterone immediately after operation. However, none of the hormonal elevations persisted by the fifth postoperative day. In contrast, patients undergoing a Fontan procedure had elevations in antidiuretic hormone, cortisol, aldosterone, renin, and angiotensin II in the immediate postoperative period. Five days postoperatively, the renin and angiotensin II levels remained elevated compared with the preoperative values. The data demonstrate that patients undergoing a bidirectional Glenn procedure and those undergoing a Fontan procedure have different patterns of hormonal response. These results suggest that hormonal factors may contribute to fluid retention after these operations.

    View details for Web of Science ID A1994MR31800011

    View details for PubMedID 8279919

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