• Simulation-Based Design of Bicuspidization of the Aortic Valve. The Journal of thoracic and cardiovascular surgery Kaiser, A. D., Haidar, M. A., Choi, P. S., Sharir, A., Marsden, A. L., Ma, M. R. 2024


    Severe congenital aortic valve pathology in the growing patient remains a challenging clinical scenario. Bicuspidization of the diseased aortic valve has proven to be a promising repair technique with acceptable durability. However, most understanding of the procedure is empirical and retrospective. This work seeks to design the optimal gross morphology associated with surgical bicuspidization with simulations, based on the hypothesis that modifications to the free edge length cause or relieve stenosis.Model bicuspid valves were constructed with varying free edge lengths and gross morphology. Fluid-structure interaction simulations were conducted in a single patient-specific model geometry. The models were evaluated for primary targets of stenosis and regurgitation. Secondary targets were assessed and included qualitative hemodynamics, geometric height, effective height, orifice area and billow.Stenosis decreased with increasing free edge length and was pronounced with free edge length ≤1.3 times the annular diameter d. With free edge length 1.5d or greater, no stenosis occurred. All models were free of regurgitation. Substantial billow occurred with free edge length ≥1.7d.Free edge length ≥1.5d was required to avoid aortic stenosis in simulations. Cases with free edge length ≥1.7d showed excessive billow and other changes in gross morphology. Cases with free edge length 1.5-1.6d have a total free edge length approximately equal to the annular circumference and appeared optimal. These effects should be studied in vitro and in animal studies.

    View details for DOI 10.1016/j.jtcvs.2023.12.027

    View details for PubMedID 38211896

  • Ex Vivo Modeling of Atrioventricular Valve Mechanics in Single Ventricle Physiology. Annals of biomedical engineering Moye, S. C., Kidambi, S., Lee, J. Y., Cowles, T. H., Gilligan-Steinberg, S. D., Bryan, A. Y., Wilkerson, R., Woo, Y. J., Ma, M. R. 2023


    Single ventricle physiology (SVP) is used to describe any congenital heart lesion that is unable to support independent pulmonary and systemic circulations. Current treatment strategies rely on a series of palliation surgeries that culminate in the Fontan physiology, which relies on the single functioning ventricle to provide systemic circulation while passively routing venous return through the pulmonary circulation. Despite significant reductions in early mortality, the presence of atrioventricular valve (AVV) regurgitation is a key predictor of heart failure in these patients. We sought to evaluate the biomechanical changes associated with the AVV in SVP physiologies. Left and right ventricles were sutured onto patient-derived 3D-printed mounts and mounted into an ex vivo systemic heart simulator capable of reproducing Norwood, Glenn, Fontan and Late Fontan physiologies. We found that the tricuspid anterior leaflet experienced elevated maximum force, average force, and maximum yank compared to the posterior and septal leaflets. Between physiologies, maximum yank was greatest in the Norwood physiology relative to the Glenn, Fontan, and Late Fontan physiologies. These contrasting trends suggest that long- and short-term mechanics of AVV failure in single ventricle differ and that AVV interventions should account for asymmetries in force profiles between leaflets and physiologies.

    View details for DOI 10.1007/s10439-023-03178-1

    View details for PubMedID 36966247

    View details for PubMedCentralID 5371563

  • Williams Syndrome: Supravalvar Aortic, Aortic Arch, Coronary and Pulmonary Arteries: Is Comprehensive Repair Advisable and Achievable? Seminars in thoracic and cardiovascular surgery. Pediatric cardiac surgery annual Ma, M., Martin, E., Algaze, C., Collins, R. T., McElhinney, D., Mainwaring, R., Hanley, F. 2023; 26: 2-8


    Williams syndrome, and various elastin protein mediated arteriopathies, presents a clinical challenge to pediatric cardiovascular specialists. In the severest phenotypes, multilevel obstruction to the systemic and pulmonic arterial systems result in biventricular dysfunction which can be imminently life-threatening. As a longstanding, quaternary referral center for complex pulmonary arteriopathies and pediatric connective tissue disease, Stanford Medicine Children's Health has developed a sizeable experience managing these patients. This manuscript is a summary of our current strategies, with a focus on our surgical techniques, peri-procedural considerations on timing and staging of various interventions, and long-term results.

    View details for DOI 10.1053/j.pcsu.2022.12.003

    View details for PubMedID 36842795

  • Force Profiles of Single Ventricle Atrioventricular Leaflets in Response to Annular Dilation and Leaflet Tethering. Seminars in thoracic and cardiovascular surgery Kidambi, S., Moye, S. C., Lee, J., Cowles, T. H., Strong, E. B., Wilkerson, R., Paulsen, M. J., Woo, Y. J., Ma, M. R. 2022


    We sought to understand how leaflet forces change in response to annular dilation and leaflet tethering in single ventricle physiology. Explanted fetal bovine tricuspid valves were sutured onto image-derived annuli and ventricular mounts. Control valves (CV) were secured to a size-matched HLHS-type annulus and compared to: 1) normal tricuspid valves (NTV) secured to a size-matched saddle-shaped annulus, 2) HLHS-type annulus with leaflet tethering (LT), 3) HLHS-type annulus with annular dilation (DIL), or 5) a combined disease model with both dilation and tethering (DIS). The specimens were tested in a systemic heart simulator at various SVPs. Leaflet forces were measured using optical strain sensors sutured to each leaflet edge. Average force in the anterior leaflet was 43.2% lower in CV compared to NTV (p<0.001). LT resulted in a 6.6% increase in average forces on the anterior leaflet (p=0.04), 10.7% increase on the posterior leaflet (p=0.03), and 14.1% increase on the septal leaflet (p<0.001). In DIL, average septal leaflet forces increased relative to the control valves by 42.2% (p=0.01). In DIS, average leaflet forces increased by 54.8% in the anterior leaflet (p<0.001), 37.6% in the posterior leaflet (p=0.03), and 79.9% in the septal leaflet (p<0.001). The anterior leaflet experiences the highest forces in the normal tricuspid annulus under SVP conditions. Annular dilation resulted in an increase in forces on the septal leaflet and leaflet tethering resulted in an increase in forces across all 3 leaflets. Annular dilation and leaflet tethering combined resulted in the largest increase in leaflet forces across all 3 leaflets.

    View details for DOI 10.1053/j.semtcvs.2022.09.012

    View details for PubMedID 36455710

  • Evaluating predicted heart mass in adolescent heart transplantation. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation Lee, J. Y., Zawadzki, R. S., Kidambi, S., Rosenthal, D. N., Dykes, J. C., Nasirov, T., Ma, M. 2022


    BACKGROUND: Predicted Heart Mass (PHM) has emerged as an attractive size matching metric in adult cardiac transplantation. However, since PHM was derived from a healthy adult cohort, its generalizability to the pediatric population is unclear. We hypothesize that PHM can be extended to older adolescents, and potentially broaden the donor pool available to this group.METHODS: The United Network for Organ Sharing database was retrospectively analyzed for patients aged 13 to 18 undergoing heart transplantation. Recipients were divided into quintiles (Q1-Q5) based on donor-to-recipient predicted heart mass ratios (PHMR). Primary end-point was graft survival at 5 years.RESULTS: Two thousand sixty-one adolescent heart transplant recipients between January 1994 and September 2019 were retrospectively analyzed. The median PHMR's for each quintile was 0.84 (0.59-0.92), 0.97 (0.92-1.02), 1.08 (1.02-1.14), 1.21 (1.14-1.30), and 1.44 (1.30-2.31). Kaplan-Meier survival curves demonstrated comparable survival across all quintiles of PHMR (p=0.9). Multivariate Cox regression showed no significant difference in graft failure of the outer quintiles when compared to the middle quintile (Q1: 1.04 HR, p=0.80; Q2: 1.02 HR, p=0.89; Q4: 1.19 HR, p=0.28; Q5: 1.02 HR, p=0.89). Significant covariates included transplant year (HR: 0.95, p < 0.0001), serum bilirubin (HR: 1.04, p=0.0004), ECMO at transplantation (HR: 2.85, p < 0.0001), and underlying diagnosis of dilated cardiomyopathy (vs congenital heart disease, HR: 0.66, p=0.0004).CONCLUSIONS: Matching by PHM is not associated with survival or risk in adolescent heart transplant recipients. Our results underscore the ongoing need to develop an improved size-matching method in pediatric heart transplantation.

    View details for DOI 10.1016/j.healun.2022.08.027

    View details for PubMedID 36210265

  • Weight Matching in Infant Heart Transplantation: A National Registry Analysis. The Annals of thoracic surgery Lee, J. Y., Kidambi, S., Zawadzki, R. S., Rosenthal, D. N., Dykes, J. C., Nasirov, T., Ma, M. 2022


    BACKGROUND: Infants account for a significant proportion of pediatric heart transplants, but also suffer from a high waitlist mortality. Donor oversizing by weight-based criteria is common practice in transplantation and is prevalent in this group. We sought to analyze the impact of oversizing on outcomes in infants.METHODS: Infant heart transplantations reported to the United Network for Organ Sharing from 01/1994 to 09/2019 were retrospectively analyzed. 2384 heart transplantation recipients were divided into quintiles (Q1-Q5) based on donor-to-recipient weight ratios (DRWR). Multivariate Cox regression was used to estimate the effect of DRWR. The primary endpoint of graft survival at one year.RESULTS: The median DRWR for each quintile was 0.90 (0.37 to 1.04), 1.17 (1.04 to 1.29), 1.43 (1.29 to 1.57), 1.74 (1.58 to 1.97), and 2.28 (1.97 to 5.00). Pairwise comparisons showed improved survival for Q3 and Q4 over each of the bottom two quintiles and the top quintile, respectively. Regression analyses found that Q3 and Q4 were protective against graft failure when compared to the bottom two quintiles, respectively. There was no difference in hazard amongst the top three quintiles. Significant covariates included primary diagnosis, ischemic time, serum bilirubin, transplant year, mechanical ventilation at transplantation, extracorporeal membrane oxygenation at transplantation. Gender, female-to-male transplantation, and mechanical circulatory support at transplantation were not significant in univariate analyses.CONCLUSIONS: Modest oversizing by DRWR (1.29 to 1.97) is associated with increased survival and lower risk in infant heart transplantation. Additional investigation is needed to establish best practices for size-matching in this population.

    View details for DOI 10.1016/j.athoracsur.2022.05.067

    View details for PubMedID 35835207

  • Biomechanical Analysis of the Ross Procedure in an Ex Vivo Left Heart Simulator. World journal for pediatric & congenital heart surgery Bryan, A. Y., Brandon Strong, E., Kidambi, S., Gilligan-Steinberg, S., Bennett-Kennett, R., Lee, J. Y., Imbrie-Moore, A., Moye, S. C., Hendrickx-Rodriguez, S., Wang, H., Dauskardt, R. H., Joseph Woo, Y., Ma, M. R. 2022; 13 (2): 166-174


    BACKGROUND: Neo-aortic pulmonary autografts often experience root dilation and valve regurgitation over time. This study seeks to understand the biomechanical differences between aortic and neo-aortic pulmonary roots using a heart simulator.METHODS: Porcine aortic, neo-aortic pulmonary, and pulmonary roots (n=6) were mounted in a heart simulator (parameters: 100 mm Hg, 37 °C, 70 cycles per minute, 5.0 L/min cardiac output). Echocardiography was used to study root distensibility (percentage change in luminal diameter between systole and diastole) and valve function. Leaflet motion was tracked with high-speed videography. After 30 min in the simulator, leaflet thickness (via cryosectioning), and multiaxial modulus (via lenticular hydrostatic deformation testing) were obtained.RESULTS: There were no significant differences between aortic and neo-aortic pulmonary leaflet motion, including mean opening velocity (218 vs 248 mm/s, P=.27) or mean closing velocity (116 vs 157 mm/s, P=.12). Distensibility was similar between aortic (8.5%, 1.56 mm) and neo-aortic pulmonary (7.8%, 1.12 mm) roots (P=.59). Compared to virgin controls, native pulmonic roots exposed to systemic pressure for 30 min had reduced leaflet thickness (630 vs 385 m, P=.049) and a reduced Young's modulus (3,125 vs 1,089 kPa, P=.077). In contrast, the aortic roots exposed to pressure displayed no significant difference in aortic leaflet thickness (1,317 vs 1,256 m, P=.27) or modulus (5,931 vs 3,631 kPa, P=.56).CONCLUSIONS: Neo-aortic pulmonary roots demonstrated equivalence in valve function and distensibility but did experience changes in biomechanical properties and morphology. These changes may contribute to long-term complications associated with the Ross procedure.

    View details for DOI 10.1177/21501351211070288

    View details for PubMedID 35238706

  • Relation Between Pulmonary Artery Pressures Measured Intraoperatively and at One-Year Catheterization After Unifocalization and Repair of Tetralogy with Major Aortopulmonary Collateral Arteries. Seminars in thoracic and cardiovascular surgery Ma, M., Peng, L. F., Zhang, Y., Wise-Faberowski, L., Martin, E., Hanley, F. L., McElhinney, D. B. 1800


    To assess the relationships between pulmonary artery (PA) pressure and the PA:aortic systolic pressure ratio measured intraoperatively and at surveillance catheterization in patients achieving complete unifocalization and repair for tetralogy of Fallot with major aortopulmonary collateral arteries (TOF/MAPCAs). This was a single-center retrospective cohort analysis of all patients who underwent complete repair of TOF/MAPCAs from 2002-2019 and received a postoperative surveillance catheterization at our center 6-24 months after surgery. Associations between intraoperative and catheter hemodynamic data were analyzed. 163 patients were included. Median systolic PA pressure was 30 (quartiles 26, 35) and 35 (28, 42) mmHg intraoperatively and at catherization respectively; systolic aortic pressure 90 (86, 100) and 84 (76, 92); and PA:aortic pressure ratio was 0.33 (0.28, 0.40) and 0.41 (0.34, 0.49). Moderate correlation was found between the intraoperative and catheter-based hemodynamics, with the majority of systolic PA pressures within 10mmHg and PA:Ao systolic ratios within 0.1. Changes in the ratio were influenced to a similar degree by differences in PA and aortic pressures. Surgical and/or catheter reinterventions were more common in patients with both higher intraoperative PA systolic pressure and PA:aortic systolic ratios and in those with greater discrepancy between intraoperative and catheterization values. PA systolic pressure and the PA:aortic systolic pressure ratio measured immediately after repair remain useful metrics for assessing the initial operative PA reconstruction, and as indicators of longer term hemodynamics. Initially elevated and subsequently discrepant PA systolic pressure and PA:aortic systolic pressure ratios were associated with higher rates of reintervention. (Figure 7).

    View details for DOI 10.1053/j.semtcvs.2022.01.004

    View details for PubMedID 35092847

  • Alternative to heart-lung transplantation for end-stage tetralogy of Fallot with major aortopulmonary collaterals: Simultaneous heart transplantation and pulmonary artery reconstruction. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation Adamson, G. T., Profita, E. L., Quinonez, Z. A., McElhinney, D. B., Rosenthal, D. N., Ma, M. n. 2021

    View details for DOI 10.1016/j.healun.2021.02.003

    View details for PubMedID 33674153

  • Longevity of large aortic allograft conduits in Tetralogy with major aortopulmonary collaterals. The Annals of thoracic surgery Ma, M. n., Arunamata, A. n., Peng, L. F., Wise-Faberowski, L. n., Hanley, F. L., McElhinney, D. B. 2021


    Appropriate conduit selection for right ventricle (RV) to pulmonary artery (PA) connection has been extensively studied, with older implantation age, pulmonary (v. aortic) homografts, and true-sizing associated with increased longevity. Notably, patients with PA arborization abnormalities (ie MAPCAs) are reported to require earlier and more frequent conduit interventions. We aim to understand the behavior of large diameter aortic homografts in patients with MAPCAs, which are programmatically utilized at our institution.This is a single-center retrospective cohort study including all children < 12 years of age who underwent RV-PA connection using an aortic homograft ≥ 16mm diameter between 2002-2019, with a primary outcome of freedom from any RV-PA reintervention and a secondary outcome of freedom from surgical reintervention. Patients were grouped by absolute and indexed conduit sizes for further analysis.A total of 336 conduits were followed for a median of 3.0 years; transcatheter (n = 30) and/or surgical (n = 35) reintervention was performed on 64 conduits. Estimated freedom from reintervention and surgical replacement was 84% and 90% at 5 years. Younger age and smaller absolute conduit size were associated with earlier reintervention, but conduit z-score (median 3.5) was not assocated with outcome.The programmatic use of oversized aortic homograft RV-PA conduits in the surgical repair of MAPCAs provides a focused experience that demonstrates similar longevity to reported best alternatives. Secondarily, conduit oversizing may improve durability and enables an increased likelihood of non-operative reintervention.

    View details for DOI 10.1016/j.athoracsur.2021.01.054

    View details for PubMedID 33600790

  • Unifocalization and pulmonary artery reconstruction in patients with tetralogy of Fallot and major aortopulmonary collateral arteries who underwent surgery before referral. The Journal of thoracic and cardiovascular surgery Ma, M. n., Zhang, Y. n., Wise-Faberowski, L. n., Lin, A. n., Asija, R. n., Hanley, F. L., McElhinney, D. B. 2020


    The study objective was to characterize and analyze outcomes in patients with tetralogy of Fallot and major aortopulmonary collateral arteries who had undergone surgery elsewhere before referral (prereferral surgery).Patients with tetralogy of Fallot and major aortopulmonary collateral arteries who underwent surgery between 2001 and 2019 at our center were reviewed. Prereferral surgery and unoperated patients were compared, as were subsets of prereferral surgery patients who had undergone different types of prior procedures. Primary outcomes included complete repair with survival to 6 months, death, and perioperative metrics.Of 576 patients studied, 200 (35%) had undergone a wide range and number of prior operations elsewhere, including 92 who had pulmonary blood supply through a shunt and 108 who had a right ventricle pulmonary artery connection. Patients who underwent prereferral surgery with an existing right ventricle pulmonary artery connection had undergone more prereferral surgery procedures than those with a shunt and were more likely to have a right ventricle outflow tract pseudoaneurysm or pulmonary artery stent (all P < .001) at the time of referral. The cumulative incidences of complete repair and death were similar regardless of prereferral surgery status, but the cumulative incidence of complete repair with 6-month survival was higher (P = .002) and of death lower (P = .18) in patients who had prior right ventricle pulmonary artery connection compared with those who had received a prior shunt only.Our comprehensive management strategy for tetralogy of Fallot and major aortopulmonary collateral arteries can be applied with excellent procedural results in both unoperated patients and those who have undergone multiple and varied procedures elsewhere.

    View details for DOI 10.1016/j.jtcvs.2020.03.062

    View details for PubMedID 32444187

  • Corrected Transposition: Anatomic Repair Using the Hemi-Mustard Atrial Baffle and Bidirectional Superior Cavopulmonary Connection. Seminars in thoracic and cardiovascular surgery. Pediatric cardiac surgery annual Ma, M. n., Mainwaring, R. D., Hanley, F. L. 2019; 22: 51–56


    Anatomic repair for congenitally corrected transposition requires thoughtful surgical planning at both initial (neonatal or late) presentation, and during definitive repair. An algorithmic approach to the overall management of this lesion, with its many associated intracardiac anomalies, is presented. Modified atrial switch with bidirectional superior cavopulmonary connection is commonly utilized and demonstrates favorable results through a 20-year experience. Herein, technical considerations learned during the implementation of this strategy are described and emphasize the concept, in selected cases, of native pulmonary root preservation by translocation as an adjunct that is uniquely suited by adopting this approach.

    View details for PubMedID 31027564

  • Comprehensive Management of Major Aortopulmonary Collaterals in the Repair of Tetralogy of Fallot. Seminars in thoracic and cardiovascular surgery. Pediatric cardiac surgery annual Ma, M., Mainwaring, R. D., Hanley, F. L. 2018; 21: 75–82


    The heterogenous anatomy of Tetralogy of Fallot with major aortopulmonary collateral arteries has engendered a similar degree of diversity in its management and, ultimately, outcome. We summarize our comprehensive treatment paradigm for this lesion evolved over 15 years of experience through 458 patients and the results obtained. An updated analysis of 307 patients treated primarily at our institution is included. A review of recent literature, comparison of management strategies, and discussion of ongoing controversies are provided.

    View details for PubMedID 29425528

  • A novel inflow cannulation strategy for pediatric mechanical circulatory support in small left ventricles. journal of thoracic and cardiovascular surgery Ma, M., Yarlagadda, V. V., Rosenthal, D. N., Maeda, K. 2017

    View details for DOI 10.1016/j.jtcvs.2017.03.034

    View details for PubMedID 28416331

  • A probabilistic neural twin for treatment planning in peripheral pulmonary artery stenosis. International journal for numerical methods in biomedical engineering Lee, J. D., Richter, J., Pfaller, M. R., Szafron, J. M., Menon, K., Zanoni, A., Ma, M. R., Feinstein, J. A., Kreutzer, J., Marsden, A. L., Schiavazzi, D. E. 2024: e3820


    The substantial computational cost of high-fidelity models in numerical hemodynamics has, so far, relegated their use mainly to offline treatment planning. New breakthroughs in data-driven architectures and optimization techniques for fast surrogate modeling provide an exciting opportunity to overcome these limitations, enabling the use of such technology for time-critical decisions. We discuss an application to the repair of multiple stenosis in peripheral pulmonary artery disease through either transcatheter pulmonary artery rehabilitation or surgery, where it is of interest to achieve desired pressures and flows at specific locations in the pulmonary artery tree, while minimizing the risk for the patient. Since different degrees of success can be achieved in practice during treatment, we formulate the problem in probability, and solve it through a sample-based approach. We propose a new offline-online pipeline for probabilistic real-time treatment planning which combines offline assimilation of boundary conditions, model reduction, and training dataset generation with online estimation of marginal probabilities, possibly conditioned on the degree of augmentation observed in already repaired lesions. Moreover, we propose a new approach for the parametrization of arbitrarily shaped vascular repairs through iterative corrections of a zero-dimensional approximant. We demonstrate this pipeline for a diseased model of the pulmonary artery tree available through the Vascular Model Repository.

    View details for DOI 10.1002/cnm.3820

    View details for PubMedID 38544354

  • Beating Heart Transplant Procedures Using Organs From Donors With Circulatory Death. JAMA network open Krishnan, A., Ruaengsri, C., Guenthart, B. A., Shudo, Y., Wang, H., Ma, M. R., MacArthur, J. W., Hiesinger, W., Woo, Y. J. 2024; 7 (3): e241828


    The use of ex vivo normothermic organ perfusion has enabled the use of deceased after circulatory death (DCD) donors for heart transplants. However, compared with conventional brain death donation, DCD heart transplantation performed with ex vivo organ perfusion involves an additional period of warm and cold ischemia, exposing the allograft to multiple bouts of ischemia reperfusion injury and may contribute to the high rates of extracorporeal membrane oxygenation usage after DCD heart transplantation.To assess whether the beating heart method of DCD heart transplantation is safe and whether it has an acceptable rate of extracorporeal membrane oxygenation use postoperatively.This case series includes 10 patients with end-stage heart failure undergoing DCD heart transplantation at a single academic medical center from October 1, 2022, to August 3, 2023. Data were analyzed from October 2022 to August 2023.Using a beating heart method of implantation of the donor allograft.The main outcome was primary graft dysfunction necessitating postoperative initiation of mechanical circulatory support. Survival and initiation of mechanical circulatory support were secondary outcomes.In this case series, 10 consecutive patients underwent DCD heart transplantation via the beating heart method. Ten of 10 recipients were male (100%), the mean (SD) age was 51.2 (13.8) years, and 7 (70%) had idiopathic dilated cardiomyopathy. Ten patients (100%) survived, and 0 patients had initiation of extracorporeal membrane oxygenation postoperatively. No other mechanical circulatory support, including intra-aortic balloon pump, was initiated postoperatively. Graft survival was 100% (10 of 10 patients), and, at the time of publication, no patients have been listed for retransplantation.In this study of 10 patients undergoing heart transplantation, the beating heart implantation method for DCD heart transplantation was safe and may mitigate ischemia reperfusion injury, which may lead to lower rates of primary graft dysfunction necessitating extracorporeal membrane oxygenation. These results are relevant to institutions using DCD donors for heart transplantation.

    View details for DOI 10.1001/jamanetworkopen.2024.1828

    View details for PubMedID 38466306

  • Impact of Congenital Heart Disease on the Outcomes of Very Low Birth Weight Infants. American journal of perinatology Chen, X., Bhombal, S., Kwiatkowski, D. M., Ma, M., Chock, V. Y. 2024


    OBJECTIVE: To investigate the association of congenital heart disease (CHD) with morbidity and mortality of very low birth weight (VLBW) infants.STUDY DESIGN: This matched case-control study included VLBW infants born at a single institution between 2001 and 2015. The primary outcome was mortality. Secondary outcomes included necrotizing enterocolitis, bronchopulmonary dysplasia (BPD), sepsis, retinopathy of prematurity, and intraventricular hemorrhage. These outcomes were assessed by comparing VLBW-CHDs with control VLBW infants matched by gestational age within a week, birth weight within 500g, sex, and birth date within a year using conditional logistic regression. Multivariable logistic regression analyzed differences in outcomes in the VLBW-CHD group between two birth periods (2001-2008 and 2009-2015) to account for changes in practice.RESULTS: In a cohort of 44 CHD infants matched with 88 controls, the mortality rate was 27% in infants with CHD and 1% in controls (p<0.0001). The VLBW-CHDs had increased BPD; (odds ratio [OR]: 7.70, 95% confidence interval [CI]: 1.96-30.29) and sepsis (OR: 10.59, 95% CI: 2.99-37.57) compared with the control VLBWs. When adjusted for preoperative ventilator use, the VLBW-CHDs still had significantly higher odds of BPD (OR: 6.97, 95% CI: 1.73-28.04). VLBW-CHDs also had significantly higher odds of both presumed and culture-positive sepsis as well as late-onset sepsis than their matched controls. There were no significant differences in outcomes between the two birth periods.CONCLUSION: VLBW-CHDs showed higher odds of BPD, sepsis, and mortality than VLBW infants without CHD. Future research should focus on the increased mortality and specific complications encountered by VLBW infants with CHD and implement targeted strategies to address these risks.KEY POINTS: · Incidence of CHD is higher in preterm infants than in term infants but the incidence of their morbidities is not well described.. · VLBW infants with CHD have higher odds of mortality, bronchopulmonary dysplasia, and sepsis.. · Future research is needed to implement targeted preventive responses..

    View details for DOI 10.1055/s-0044-1781460

    View details for PubMedID 38408479

  • Right Ventricular and Outflow Tract Functional Characteristics After Repair of Tetralogy of Fallot with Major Aortopulmonary Collaterals. Pediatric cardiology Long, Z. B., Punn, R., Zhang, Y., Arunamata, A. A., Asija, R., Ma, M., Hanley, F. L., McElhinney, D. B. 2024


    This study describes right ventricle (RV) characteristics and right ventricle to pulmonary artery (RV-PA) conduit function pre- and post-repair in patients with tetraology of Fallot with major aortopulmonary collaterals (TOF/MAPCAs). We reviewed patients who underwent single-stage, complete unifocalization, and repair of TOF/MAPCAs between 2006 and 2019 with available pre- and early postoperative echocardiograms. For a subset of patients, 6-12 month follow-up echocardiogram was available. RV and left ventricle (LV) characteristics and RV-PA conduit function were reviewed. Wilcoxon signed rank test and McNemar's test were used. 170 patients were reviewed, 46 had follow-up echocardiograms. Tricuspid valve annular plane systolic excursion (TAPSE) Z-scores were reduced from pre- (Z-score 0.01) to post-repair (Z-score -4.5, p < 0.001), improved but remained abnormal at follow-up (Z-score -4.0, p < 0.001). RV fractional area change (FAC) and LV ejection fraction were not significantly different before and after surgery. Conduit regurgitation was moderate or greater in 11% at discharge, increased to 65% at follow-up. RV-PA conduit failure (severe pulmonary stenosis or severe pulmonary regurgitation) was noted in 61, and 63% had dilated RV (diastolic RV area Z-score > 2) at follow-up. RV dilation correlated with the severe conduit regurgitation (p = 0.018). Longitudinal RV function was reduced after complete repair of TOF/MAPCAs, with decreased TAPSE and preserved FAC and LV ejection fraction. TAPSE improved but did not normalize at follow-up. Severe RV-PA conduit dysfunction was observed prior to discharge in 11% of patients and in 61% at follow-up. RV dilation was common at follow-up, especially in the presence of severe conduit regurgitation.

    View details for DOI 10.1007/s00246-024-03412-0

    View details for PubMedID 38360921

    View details for PubMedCentralID 6035101

  • Esophageal lung, pulmonary artery sling and congenital tracheal stenosis: A case report JOURNAL OF PEDIATRIC SURGERY CASE REPORTS Liang, N. E., Kim, G. S., Gugig, R., Ma, M., Coll, A., Sidell, D., Bruzoni, M. 2024; 101
  • Avoiding Obstructive Behavior. The Annals of thoracic surgery Choi, P. S., Ma, M. 2023

    View details for DOI 10.1016/j.athoracsur.2023.11.010

    View details for PubMedID 37952758

  • SDF4CHD: Generative Modeling of Cardiac Anatomies with Congenital Heart Defects. ArXiv Kong, F., Stocker, S., Choi, P. S., Ma, M., Ennis, D. B., Marsden, A. 2023


    Congenital heart disease (CHD) encompasses a spectrum of cardiovascular structural abnormalities, often requiring customized treatment plans for individual patients. Computational modeling and analysis of these unique cardiac anatomies can improve diagnosis and treatment planning and may ultimately lead to improved outcomes. Deep learning (DL) methods have demonstrated the potential to enable efficient treatment planning by automating cardiac segmentation and mesh construction for patients with normal cardiac anatomies. However, CHDs are often rare, making it challenging to acquire sufficiently large patient cohorts for training such DL models. Generative modeling of cardiac anatomies has the potential to fill this gap via the generation of virtual cohorts; however, prior approaches were largely designed for normal anatomies and cannot readily capture the significant topological variations seen in CHD patients. Therefore, we propose a type- and shape-disentangled generative approach suitable to capture the wide spectrum of cardiac anatomies observed in different CHD types and synthesize differently shaped cardiac anatomies that preserve the unique topology for specific CHD types. Our DL approach represents generic whole heart anatomies with CHD type-specific abnormalities implicitly using signed distance fields (SDF) based on CHD type diagnosis, which conveniently captures divergent anatomical variations across different types and represents meaningful intermediate CHD states. To capture the shape-specific variations, we then learn invertible deformations to morph the learned CHD type-specific anatomies and reconstruct patient-specific shapes. Our approach has the potential to augment the image-segmentation pairs for rarer CHD types for cardiac segmentation and generate cohorts of CHD cardiac meshes for computational simulation.

    View details for PubMedID 37961745

    View details for PubMedCentralID PMC10635288

  • Prenatal Diagnosis and Postnatal Management of a Fetal Pericardial Mass. NeoReviews Weigel, N., Hintz, S., Kaplinski, M., Barth, R., Balakrishnan, K., Panelli, D., Ma, M., Chitkara, R. 2023; 24 (10): e683-e689

    View details for DOI 10.1542/neo.24-10-e683

    View details for PubMedID 37777619

  • "Percutaneous" technique for direct external access to and stenting of obstructed pediatric ventricular assist device inflow cannula. JTCVS techniques Taylor, A., Lee, K. J., Felmly, L., Syed, A., Almond, C., Shuttleworth, P., Issapour, A., Babb, A., Ma, M., Martin, E. 2023; 21: 195-198

    View details for DOI 10.1016/j.xjtc.2023.07.024

    View details for PubMedID 37854820

    View details for PubMedCentralID PMC10580173

  • 20-Year Experience With Repair of Pulmonary Atresia or Stenosis and Major Aortopulmonary Collateral Arteries. Journal of the American College of Cardiology McElhinney, D. B., Asija, R., Zhang, Y., Jaggi, A., Shek, J., Peng, L. F., Boltz, M. G., Ma, M., Martin, E., Hanley, F. L. 2023; 82 (12): 1206-1222


    BACKGROUND: We have followed a consistent, albeit evolving, strategy for the management of patients with pulmonary atresia or severe stenosis and major aortopulmonary collateral arteries (MAPCAs) that aims to achieve complete repair with low right ventricular pressure by completely incorporating blood supply and relieving stenoses to all lung segments.OBJECTIVES: The purpose of this study was to characterize our 20-year institutional experience managing patients with MAPCAs.METHODS: We reviewed all patients who underwent surgery for MAPCAs and biventricular heart disease from November 2001 through December2021.RESULTS: During the study period, 780 unique patients underwent surgery. The number of new patients undergoing surgery annually was relatively steady during the first 15 years, then increased substantially thereafter. Surgery before referral had been performed in almost 40% of patients, more often in our recent experience than earlier. Complete repair was achieved in 704 patients (90%), 521 (67%) during the first surgery at our center, with a median right ventricular to aortic pressure ratio of 0.34 (25th, 75th percentiles: 0.28, 0.40). The cumulative incidence of mortality was 15% (95% CI: 12%-19%) at 10 years, with no difference according to era of surgery (P=0.53). On multivariable Cox regression, Alagille syndrome (HR: 2.8; 95%CI: 1.4-5.7; P=0.004), preoperative respiratory support (HR: 2.0; 95%CI: 1.2-3.3; P=0.008), and palliative first surgery at our center (HR: 3.5; 95%CI: 2.3-5.4; P< 0.001) were associated with higher risk of death.CONCLUSIONS: In a growing pulmonary artery reconstruction program, with increasing volumes and an expanding population of patients who underwent prior surgery, outcomes of patients with pulmonary atresia or stenosis andMAPCAs have continued to improve.

    View details for DOI 10.1016/j.jacc.2023.06.041

    View details for PubMedID 37704311

  • Comparing Apples to Apples: Exploring public reporting of congenital cardiac surgery outcomes based on common congenital heart operations. The Journal of thoracic and cardiovascular surgery Nathan, M., Gauvreau, K., White, O., Anderson, B. R., Bacha, E. A., Barron, D. J., Cleveland, J., Del Nido, P. J., Eghtesady, P., Galantowicz, M., Kennedy, A., Kohlsaat, K., Ma, M., Mattila, C., Van Arsdell, G., Gaynor, J. W. 2023


    We sought to simplify reporting of outcomes in congenital heart surgery that compares well-defined patient groups, accommodates multiple stakeholder needs while being easily understandable.We selected 19 commonly performed congenital heart surgeries ranging in complexity from repair of atrial septal defects (ASD) to the Norwood procedure. Strict inclusion/exclusion criteria ensured the creation of 19 well defined diagnosis/procedure cohorts. Preoperative, procedural, and postoperative data were collected for consecutive eligible patients from 9 centers between 1/1/2016 to 12/31/2021. Unadjusted operative mortality rates and hospital length of stay for each of the 19 diagnosis/procedure cohorts were summarized in aggregate and stratified by each center.Of 8572 eligible cases included, numbers in the 19 diagnosis/procedure cohorts ranged from 73 for tetralogy of Fallot repair after prior palliation to 1224 for ventricular septal defect (VSD) repairs for isolated VSD. In aggregate, the unadjusted mortality ranged from 0% for ASD repair to 28.4% for Hybrid Stage I. There was significant heterogeneity in case-mix and mortality for different diagnosis/procedure cohorts across centers (e.g., ASO/VSD n=7 to 42, mortality 0% to 7.4%; Norwood procedure n=16 to 122, mortality 5.3% to 25%).Reporting of institutional case volumes and outcomes within well-defined diagnosis/procedure cohorts can enable centers to benchmark outcomes, understand trends in mortality, and direct quality improvement. When made public, this type of report could provide parents with information on institutional volumes and outcomes and allow them to better understand the experience of each program with operations for specific congenital heart defects.

    View details for DOI 10.1016/j.jtcvs.2023.08.052

    View details for PubMedID 37689234

  • Short- and Mid-Term Results of Pulmonary Valve Replacement with the Inspiris Valve. The Annals of thoracic surgery Ragheb, D. K., Martin, E., Jaggi, A., Lui, G. K., Maskatia, S. A., Ma, M., Hanley, F. L., McElhinney, D. B. 2023


    BACKGROUND: Various bioprosthetic valves are used off-label for pulmonary valve replacement (PVR), but there is no consensus about whether a particular valve is best for this application. Recently, the Inspiris Valve was approved for aortic valve replacement, and surgeons have begun utilizing it for PVR. There is limited evidence about the performance of the Inspiris valve compared to other valves in the pulmonary position.METHODS: We reviewed all patients who underwent PVR with a size 19-27mm Inspiris or Mosaic valve from 2007-2022. Mid-term outcomes included freedom from moderate or severe pulmonary regurgitation (PR), a maximum Doppler gradient >36mmHg, and freedom from reintervention.RESULTS: A total of 225 consecutive patients who underwent PVR with a size 19-27mm Mosaic (n=163) or Inspiris (n=62) valve were included. There was no difference in baseline characteristics. Early postoperative gradients were low in both groups, but higher in the Mosaic cohort, and neither group had more than mild PR on discharge. On uni- and multivariable analysis, Inspiris valves were significantly more likely to develop moderate or greater PR over time. There was no significant difference between the valves in freedom from reintervention or from a maximum gradient >36mmHg.CONCLUSIONS: Early and short-term gradients were similar in patients undergoing PVR with Inspiris and Mosaic valves, but significant PR was more common in patients who received an Inspiris valve. These preliminary findings suggest that the durability of the Inspiris valve in the pulmonary position may not be superior to other bioprosthetic valves used for PVR.

    View details for DOI 10.1016/j.athoracsur.2023.07.049

    View details for PubMedID 37625611

  • An integrated program to expand donor utilization in pediatric heart transplantation: Case report of successful transplant with multiple donor risk factors. Pediatric transplantation Torpoco Rivera, D. M., Hollander, S. A., Almond, C., Profita, E., Dykes, J. C., Raissadati, A., Lee, J., Sacks, L. D., Kleiman, Z. I., Lee, E., Rosenthal, A., Rosenthal, D. N., Nasirov, T., Ma, M., Martin, E., Chen, S. 2023: e14584


    Pediatric heart transplantation (HT) continues to be limited by the shortage of donor organs, distance constraints, and the number of potential donor offers that are declined due to the presence of multiple risk factors.We report a case of successful pediatric HT in which multiple risk factors were mitigated through a combination of innovative donor utilization improvement strategies.An 11-year-old, 25-kilogram child with cardiomyopathy and pulmonary hypertension, on chronic milrinone therapy and anticoagulated with apixaban, was transplanted with a heart from a Hepatitis C virus positive donor and an increased donor-to-recipient weight ratio. Due to extended geographic distance, an extracorporeal heart preservation system (TransMedics™ OCS Heart) was used for procurement. No significant bleeding was observed post-operatively, and she was discharged by post-operative day 15 with normal biventricular systolic function. Post-transplant Hepatitis C virus seroconversion was successfully treated.Heart transplantation in donors with multiple risk factor can be achieved with an integrative team approach and should be taken into consideration when evaluating marginal donors in order to expand the current limited donor pool in pediatric patients.

    View details for DOI 10.1111/petr.14584

    View details for PubMedID 37470130

  • Outcomes After Development of Ventricular Arrhythmias in Single Ventricular Heart Disease Patients With Fontan Palliation. Circulation. Arrhythmia and electrophysiology Giacone, H. M., Chubb, H., Dubin, A. M., Motonaga, K. S., Ceresnak, S. R., Goodyer, W. R., Hanish, D., Trela, A. V., Boramanand, N., Lencioni, E., Boothroyd, D., Graber-Naidich, A., Wright, G., Haeffele, C., Hollander, S. A., McElhinney, D. B., Ma, M., Hanley, F. L., Chen, S. 2023: e011143


    With the advent of more intensive rhythm monitoring strategies, ventricular arrhythmias (VAs) are increasingly detected in Fontan patients. However, the prognostic implications of VA are poorly understood. We assessed the incidence of VA in Fontan patients and the implications on transplant-free survival.Medical records of Fontan patients seen at a single center between 2002 and 2019 were reviewed to identify post-Fontan VA (nonsustained ventricular tachycardia >4 beats or sustained >30 seconds). Patients with preFontan VA were excluded. Hemodynamically unstable VA was defined as malignant VA. The primary outcome was death or heart transplantation. Death with censoring at transplant was a secondary outcome.Of 431 Fontan patients, transplant-free survival was 82% at 15 years post-Fontan with 64 (15%) meeting primary outcome of either death (n=16, 3.7%), at a median 4.6 (0.4-10.2) years post-Fontan, or transplant (n=48, 11%), at a median of 11.1 (5.9-16.2) years post-Fontan. Forty-eight (11%) patients were diagnosed with VA (90% nonsustained ventricular tachycardia, 10% sustained ventricular tachycardia). Malignant VA (n=9, 2.0%) was associated with younger age, worse systolic function, and valvular regurgitation. Risk for VA increased with time from Fontan, 2.4% at 10 years to 19% at 20 years. History of Stage 1 surgery with right ventricular to pulmonary artery conduit and older age at Fontan were significant risk factors for VA. VA was strongly associated with an increased risk of transplant or death (HR, 9.2 [95% CI, 4.5-18.7]; P<0.001), with a transplant-free survival of 48% at 5-year post-VA diagnosis.Ventricular arrhythmias occurred in 11% of Fontan patients and was highly associated with transplant or death, with a transplant-free survival of <50% at 5-year post-VA diagnosis. Risk factors for VA included older age at Fontan and history of right ventricular to pulmonary artery conduit. A diagnosis of VA in Fontan patients should prompt increased clinical surveillance.

    View details for DOI 10.1161/CIRCEP.122.011143

    View details for PubMedID 37254747

  • Colocutaneous Fistula Following Pediatric Bivad Implantation, A Rare but Serious Complication Rangu, S., Murray, J., Shiu, A., Martin, E., Nasirov, T., Bruzoni, M., Chen, S., Rosenthal, D., Ma, M., Dykes, J. ELSEVIER SCIENCE INC. 2023: S447-S448
  • The Intra-Operative "Gross Pathology": An Approach to Determining Heart-Only Versus Heart-Liver Transplantation in Fontan Patients Rivera, D., Martin, E., Ma, M., Hollander, S., Bensen, R., Ebel, N., Zhang, K., Bonham, A., Gallo, A., Esquivel, C. O., Navaratnam, M., Rosenthal, D., Chen, S. ELSEVIER SCIENCE INC. 2023: S215
  • Racial Disparities in Pediatric Heart Transplantation: A National Registry Analysis Chan, K., Jacobs, N., Lee, J., Kidambi, S., Zawadzki, R., Kim, E., Dykes, J., Rosenthal, D., Ma, M. ELSEVIER SCIENCE INC. 2023: S37-S38
  • Evaluating the Impact of Donor-Recipient Race Mismatch on Graft Survival in Infant Heart Transplantation So, B. J., Lee, J., Kidambi, S., Dykes, J., Rosenthal, D., Ma, M. ELSEVIER SCIENCE INC. 2023: S383
  • Through the "Chimney": Berlin Heart Excor Pediatric Ventricular Assist Device Inflow Stenting via a Novel Direct Access to Inflow Tubing Taylor, A. C., Lee, K., Felmly, L. M., Issapour, A., Almond, C., Ma, M., Martin, E. ELSEVIER SCIENCE INC. 2023: S448
  • Use of the SherpaPak Cardiac Transport System for Infant and Pediatric Donor Hearts: An Initial Experience Profita, E. L., Lee, E., Ma, M., Martin, E., Hollander, S., Rosenthal, D., Almond, C., Nasirov, T. ELSEVIER SCIENCE INC. 2023: S187-S188
  • Serial Lung Perfusion Scintigraphy After Unifocalization and Repair of Tetralogy of Fallot With Major Aortopulmonary Collaterals. World journal for pediatric & congenital heart surgery Wise-Faberowski, L., Long, J., Ma, M., Nadel, H. R., Shek, J., Feinstein, J. A., Martin, E., Hanley, F. L., McElhinney, D. B. 2023: 21501351231162959


    BACKGROUND: In patients with tetralogy of Fallot and major aortopulmonary collaterals (MAPCAs), pulmonary blood supply is highly variable. Our approach to this condition emphasizes complete unifocalization of the pulmonary circulation, incorporating all lung segments and addressing stenoses out to the segmental level. Post-repair, we recommend serial lung perfusion scintigraphy (LPS) to assess short-term changes in pulmonary blood flow distribution.METHODS: We reviewed post-discharge and follow-up LPS performed through three years post-repair and analyzed serial changes in perfusion, risk factors for change, and the relationship between LPS parameters and pulmonary artery reintervention.RESULTS: Of 543 patients who had postoperative LPS results in our system, 317 (58%) had only a predischarge LPS available for review, while 226 had 1 (20%) or more (22%) follow-up scans within three years. Overall, pulmonary flow distribution prior to discharge was balanced, and there was minimal change over time; however, there was considerable patient-to-patient variation in both metrics. On multivariable mixed modeling, time after repair (P=.025), initial anatomy consisting of a ductus arteriosus to one lung (P<.001), and age at repair (P=.014) were associated with changes on serial LPS. Patients who had follow-up LPS were more likely to undergo pulmonary artery reintervention, but within that cohort, LPS parameters were not associated with reintervention risk.CONCLUSION: Serial LPS during the first year after MAPCAs repair is a noninvasive method of screening for significant post-repair pulmonary artery stenosis that occurs in a small but important minority of patients. In patients who received follow-up LPS beyond the perioperative period, there was minimal change over time in the population overall, but large changes in some patients and considerable variability. There was no statistical association between LPS findings and pulmonary artery reintervention.

    View details for DOI 10.1177/21501351231162959

    View details for PubMedID 36972512

  • Analysis of risk factors associated with extracorporeal membrane oxygenation after surgical repair of peripheral pulmonary artery stenoses. JTCVS open Felmly, L. M., Mainwaring, R. D., Algaze, C., Martin, E., Ma, M., Hanley, F. L. 2023; 13: 344-356


    Acute lung injury is a known complication of pulmonary artery reconstruction for peripheral pulmonary artery stenosis. Severe cases may require support with extracorporeal membrane oxygenation. The purpose of this study was to evaluate the characteristics of patients requiring extracorporeal membrane oxygenation after pulmonary artery reconstruction.This was a retrospective study of 150 patients who underwent surgical repair of peripheral pulmonary artery stenosis at our institution from 2002 to 2022. Underlying diagnoses included Williams syndrome (n = 44), Alagille syndrome (n = 43), elastin arteriopathy (n = 21), tetralogy of Fallot (n = 21), and other (n = 21). Characteristics of patients who required extracorporeal membrane oxygenation were compared with those who did not require extracorporeal membrane oxygenation.Eleven of the 150 patients undergoing pulmonary artery reconstruction (7.3%) required postoperative extracorporeal membrane oxygenation support (10 for acute lung injury and 1 for cardiac insufficiency). Four patients receiving extracorporeal membrane oxygenation had Williams syndrome, 3 patients had Alagille, and 4 patients had tetralogy of Fallot. Patients requiring extracorporeal membrane oxygenation had a higher preoperative right ventricle to aortic peak systolic pressure ratios (mean 1.14 vs 0.95), greater number of pulmonary artery ostial interventions (median, 23 vs 17), and longer duration of cardiopulmonary bypass (median, 597 vs 400 minutes). There were 3 in-hospital deaths (2.0%), 2 of whom required postoperative extracorporeal membrane oxygenation support.The data demonstrate multiple differences between patients who did and did not require extracorporeal membrane oxygenation after surgical repair of peripheral pulmonary artery stenosis. These results suggest that the preoperative extent of disease may predispose to the development of acute lung injury requiring extracorporeal membrane oxygenation support.

    View details for DOI 10.1016/j.xjon.2023.01.011

    View details for PubMedID 37063146

    View details for PubMedCentralID PMC10091391

  • Single-port robotic transcervical long-segment thoracic tracheal reconstruction: Cadaveric proof-of-concept study. JTCVS techniques Lui, N. S., Holsinger, F. C., Ma, M. R., Janus, J. R., Balakrishnan, K. 2022; 16: 231-236


    Slide tracheoplasty is the standard technique to repair congenital long-segment tracheal stenosis. This operation most commonly requires median sternotomy, which has drawbacks in young children. We hypothesized that a transcervical approach without sternotomy would be feasible if done with a single-port robotic system.This proof-of concept study was performed in 2 small adult cadavers using a single-port robotic surgical system via a small neck incision. Relevant information, including operative time and details of operative technique, were recorded.Long-segment slide tracheoplasty was completed successfully in 2 cadavers using a small neck incision and a single-port robotic surgical system. Strengths and pitfalls of the technique were identified, including technical refinements from the first attempt to the second. Operative time for robotic mobilization, incision, and anastomosis of the trachea was comparable to standard open approaches.Small-incision transcervical slide tracheoplasty, assisted by a single-port surgical robotic system, is feasible in a human cadaver. More work is needed to determine safety and applicability in live patients, particularly in children.

    View details for DOI 10.1016/j.xjtc.2022.08.025

    View details for PubMedID 36510525

    View details for PubMedCentralID PMC9735391

  • Criteria for Early Pacemaker Implantation in Patients With Postoperative Heart Block After Congenital Heart Surgery. Circulation. Arrhythmia and electrophysiology Duong, S. Q., Shi, Y., Giacone, H., Navarre, B., Gal, D., Han, B., Sganga, D., Ma, M., Reddy, C. D., Shin, A., Kwiatkowski, D. M., Dubin, A. M., Scheinker, D., Algaze, C. A. 2022: e011145


    Guidelines recommend observation for atrioventricular node recovery until postoperative days (POD) 7 to 10 before permanent pacemaker placement (PPM) in patients with heart block after congenital cardiac surgery. To aid in surgical decision-making for early PPM, we established criteria to identify patients at high risk of requiring PPM.We reviewed all cases of second degree and complete heart block (CHB) on POD 0 from August 2009 through December 2018. A decision tree model was trained to predict the need for PPM amongst patients with persistent CHB and prospectively validated from January 2019 through March 2021. Separate models were developed for all patients on POD 0 and those without recovery by POD 4.Of the 139 patients with postoperative heart block, 68 required PPM. PPM was associated with older age (3.2 versus 1.0 years; P=0.018) and persistent CHB on POD 0 (versus intermittent CHB or second degree heart block; 87% versus 58%; P=0.001). Median days [IQR] to atrioventricular node recovery was 2 [0-5] and PPM was 9 [6-11]. Of the 100 cases of persistent CHB (21 in the validation cohort), 59 (59%) required PPM. A decision tree model identified 4 risk factors for PPM in patients with persistent CHB: (1) aortic valve replacement, subaortic stenosis repair, or Konno procedure; (2) ventricular L-looping; (3) atrioventricular valve replacement; (4) and absence of preoperative antiarrhythmic agent (in POD 0 model only). The POD 4 model specificity was 0.89 [0.67-0.99] and positive predictive value was 0.94 [95% CI 0.81-0.98], which was stable in prospective validation (positive predictive value 1.0).A data-driven analysis led to actionable criteria to identify patients requiring PPM. Patients with left ventricular outflow tract surgery, atrioventricular valve replacement, or ventricular L-Looping could be considered for PPM on POD 4 to reduce risks of temporary pacing and improve care efficiency.

    View details for DOI 10.1161/CIRCEP.122.011145

    View details for PubMedID 36306332

  • Are There Still Reasons to Use Porcine Small Intestinal Submucosa? Journal of the American College of Cardiology Ma, M. 2022; 80 (11): 1069-1070

    View details for DOI 10.1016/j.jacc.2022.07.002

    View details for PubMedID 36075676

  • Commentary: The Devil in Z Details SEMINARS IN THORACIC AND CARDIOVASCULAR SURGERY Ma, M. 2022; 34 (3): 1010
  • Surgical repair of peripheral pulmonary artery stenosis: A 2-decade experience with 145 patients. The Journal of thoracic and cardiovascular surgery Felmly, L. M., Mainwaring, R. D., Collins, R. T., Lechich, K., Martin, E., Ma, M., Hanley, F. L. 2022


    BACKGROUND: Peripheral pulmonary artery stenosis (PPAS) is a relatively rare form of congenital heart disease often associated with Williams syndrome, Alagille syndrome, and elastin arteriopathy. This disease is characterized by stenoses at nearly all lobar and segmental ostia and results in systemic-level right ventricular pressures. The current study summarizes our experience with the surgical treatment of PPAS.METHODS: This was a retrospective review of 145 patients who underwent surgical repair of PPAS. This included 43 patients with Williams syndrome, 39 with Alagille syndrome, and 21 with elastin arteriopathy. Other diagnoses include tetralogy of Fallot with PPAS (n=21), truncus arteriosus (n=5), transposition (n=3), double-outlet right ventricle (n=2), arterial tortuosity syndrome (n=3), and other (n=8).RESULTS: The median preoperative right ventricle to aortic peak systolic pressure ratio was 1.01 (range, 0.50-1.60) which was reduced to 0.30 (range, 0.17-0.60) postoperatively. The median number of ostial repairs was 17 (range, 6-34) and median duration of cardiopulmonary bypass was 398minutes (range, 92-844). There were 3 in-hospital deaths (2.1%). The median duration of follow-up was 26months (range, 1-220) with 4 late deaths (2.9%). Eighty-two patients have subsequently undergone catheterization and 74 had a pressure ratio <0.50.CONCLUSIONS: The surgical treatment of PPAS resulted in a 70% reduction in right ventricular pressures. At 3years, freedom from death was 94% and 90% of those evaluated maintained low pressures. These results suggest that the surgical treatment of PPAS is highly effective in most patients.

    View details for DOI 10.1016/j.jtcvs.2022.07.037

    View details for PubMedID 36088147

  • Virtual Surgical Skills Training in a High School Summer Program. The Annals of thoracic surgery Bajaj, S. S., Patel, H. H., Fann, J. I., Ma, M., Lui, N. S. 2022


    BACKGROUND: The COVID-19 pandemic has disrupted components of traditional education with shifts toward virtual platforms. Here, we describe the virtual approach to basic surgical skills training during our high school program in the summers of 2020 and 2021.METHODS: Two 2-week sessions were held via Zoom with 99 students in 2020 and 198 students in 2021. Each student was sent surgical supplies and instruments. Interactive lectures were held each morning and basic surgical skills instruction each afternoon. After the session, survey links were distributed to students to complete an anonymous 37-item questionnaire regarding surgical skills confidence, simulation kit satisfaction, and technical difficulties.RESULTS: Of the 297 students, 270 (90.9%) completed the questionnaire, including 91 (91.9%) in 2020 and 179 (90.4%) in 2021. On a scale of 1 (fair) to 5 (excellent), students in 2020 and 2021 reported similar confidence in instrument handling (4-5: 90.0% vs 86.3%, p=0.38), suturing skin (4-5: 88.9% vs 82.8%, p=0.19), and thoracic aorta suturing (4-5: 73.3% vs 73.6%, p=0.97). Students reported greater confidence in 2020 on knot-tying (4-5: 98.9% vs 87.9%, p=0.002), coronary vessel suturing (4-5: 82.2% vs 65.5%, p<0.001), and valve model suturing (4-5: 68.5% vs 50.3%, p=0.005) than students in 2021. Students had similar satisfaction rates with the program (extremely or somewhat satisfied: 92.3% vs 86.0%, p=0.51) between 2020 and 2021.CONCLUSIONS: Virtual education carries the potential for basic surgical skills training for a more widespread audience with less access to direct surgical education. Further research is needed to optimize teaching finer surgical skills.

    View details for DOI 10.1016/j.athoracsur.2022.07.034

    View details for PubMedID 35934065

  • Subcutaneous Treprostinil Improves Surgical Candidacy for Next Stage Palliation in Single Ventricle Patients With High-Risk Hemodynamics. Seminars in thoracic and cardiovascular surgery Sullivan, R. T., Handler, S. S., Feinstein, J. A., Ogawa, M., Liu, E., Ma, M., Hopper, R. K., Norris, J., Hollander, S. A., Chen, S. 2022


    Single ventricle (SV) patients with pulmonary vascular disease (SV-PVD) are considered poor surgical candidates for Glenn or Fontan palliation. Given limited options for Stage 1 (S1) and Stage 2 (S2) SV patients with SV-PVD, we report on the use of subcutaneous treprostinil (TRE) to treat SV-PVD in this population. This single-center, retrospective cohort study examined SV patients who were not candidates for subsequent surgical palliation due to SV-PVD and were treated with TRE. The primary outcome was ability to progress to the next surgical stage; secondary outcomes included changes in hemodynamics after TRE initiation. Between 3/2014 and 8/2021, 17 SV patients received TRE for SV-PVD: 11 after S1 and 6 after S2 (median PVR 4.1 [IQR 3.2-4.8] WU*m2, and 5.0 [IQR 1.5-6.1] WU*m2, respectively). Nine of eleven (82%) S1 progressed to S2, and 2 (18%) underwent heart transplant (HTx). Three of six (50%) S2 progressed to Fontan, 1 underwent HTx and 2 are awaiting Fontan on TRE. TRE significantly decreased PVR in S1 patients with median post-treatment PVR of 2.0 (IQR 1.5-2.6) WU*m2. TRE can allow for further surgical palliation in select pre-Fontan patients with SV-PVD, obviating the need for HTx. Improvement in PVR was significant in S1 patients and persisted beyond discontinuation of therapy for most patients.

    View details for DOI 10.1053/j.semtcvs.2022.07.011

    View details for PubMedID 35931345

  • Innominate artery patency after direct cannulation in neonates. JTCVS techniques Choi, P. S., Nasirov, T., Hanley, F., Peng, L., McElhinney, D. B., Ma, M. 2022; 14: 171-176


    Objective: The study objective was to determine the short-term incidence of innominate artery stenosis for neonates who underwent direct innominate artery cannulation during the Norwood procedure.Methods: This is a retrospective, single-institution review of 92 patients who underwent the Norwood procedure with direct innominate artery cannulation from 2006 to 2017. The primary outcome was angiographic evidence of patency at pre-Glenn cardiac catheterization. Patient characteristics, intraoperative surgical and hemodynamic measurements, and postoperative neurologic findings were recorded.Results: At a median age of 5.0days, 92 neonates underwent the Norwood procedure with direct innominate artery cannulation. These patients underwent cardiac catheterization at a median of 3.0months after the index operation. In 5 of 92 patients with catheterization images available for review, there was angiographic evidence of mild innominate artery stenosis, and none had moderate or severe stenosis. Review of follow-up records did not reveal evidence of clinically significant stenosis or innominate artery reintervention.Conclusions: In neonates undergoing the Norwood procedure with direct innominate cannulation, innominate artery stenosis was uncommon and clinically significant stenosis did not occur.

    View details for DOI 10.1016/j.xjtc.2022.06.001

    View details for PubMedID 35967223

  • Commentary: Operating on fewer veins in vain. JTCVS open Ma, M. 2022; 10: 322-323

    View details for DOI 10.1016/j.xjon.2021.12.008

    View details for PubMedID 36004213

  • Identifying Predictors of Pediatric Heart Only versus Combined Heart-Liver Transplantation. Zhang, K., Chen, S., Syed, A., Gallo, A., Esquivel, C., Bonham, C., Hollander, S., Ma, M., Han, J., Ebel, N. WILEY. 2022: 476-477
  • Tetralogy of Fallot and Aortic Dissection: Implications in Management. JACC. Case reports Vaikunth, S. S., Chan, J. L., Woo, J. P., Bykhovsky, M. R., Lui, G. K., Ma, M., Romfh, A. W., Lamberti, J., Mastrodicasa, D., Fleischmann, D., Fischbein, M. P. 2022; 4 (10): 581-586


    We present the case of a 61-year-old man with tetralogy of Fallot postrepair and mechanical aortic valve replacement with an aortic root/ascending/arch aneurysm with chronic type A aortic dissection. He underwent uncomplicated aortic root and total arch replacement. Continued surveillance for aortic aneurysm is necessary in the tetralogy of Fallot population. (Level of Difficulty: Intermediate.).

    View details for DOI 10.1016/j.jaccas.2022.02.021

    View details for PubMedID 35615213

  • Surgical Repair of Supravalvar Aortic Stenosis in Association With Transverse and Proximal Descending Aortic Abnormalities. World journal for pediatric & congenital heart surgery Mainwaring, R. D., Collins, R. T., Ma, M., Martin, E., Arunamata, A., Algaze-Yojay, C., Hanley, F. L. 2022; 13 (3): 353-360


    BACKGROUND: Supravalvar aortic stenosis (SVAS) may be an isolated defect of the proximal ascending aorta. However, more severe cases have extension of the arteriopathy into the transverse and proximal descending aorta. The purpose of this study was to review our experience with SVAS with and without aortic arch arteriopathy.METHODS: This was a retrospective review of 58 patients who underwent surgical repair of SVAS. The median age at repair was 18 months. A total of 37 patients had Williams syndrome. A total of 31 (53%) patients had associated peripheral pulmonary artery stenosis and 23 (39%) had coronary artery ostial stenosis (CAOS).RESULTS: A total of 37 of 58 (64%) patients had surgical repair of SVAS without the need for arch intervention while 21 (36%) patients had repair of the distal aortic arch. There were 3 (5.2%) operative deaths, 2 of whom had aortic arch involvement and one without arch involvement. There were 2 deaths after discharge from the hospital. Patients who needed arch surgery were more likely to have severe arch gradients compared to those without arch involvement (71% vs 30%, P < .05), were more likely to undergo concomitant procedures for peripheral pulmonary artery stenosis or CAOS (90% vs 62%, P < .05), and to have Williams syndrome (86% vs 51%, P < .05).CONCLUSIONS: More than one-third of patients who had SVAS repair at our institution had procedures directed at the transverse or proximal descending aorta. Patients with arch involvement had more severe arch obstruction, required more concomitant procedures, and were more likely to have Williams syndrome.

    View details for DOI 10.1177/21501351221085975

    View details for PubMedID 35446223

  • Neurologic complications in en bloc pediatric heart-liver transplants Pan, J., Bensen, R., Ebel, N., Mendoza, J., Ma, M., Hollander, S., Gallo, A., Esquivel, C. O., Bonham, A. WILEY. 2022
  • Long-Term Outcomes of ECMO Post-Heart Transplant Iqbal, M. S., Wujcik, K. A., Nair, A., Yarlagadda, V., Ma, M. R., Hollander, S. A., Profita, E. ELSEVIER SCIENCE INC. 2022: S505-S506
  • Pediatric VAD Growth in the US: What Factors May Be Driving Growth Jumps? Iqbal, M. S., Sweat, K., Dykes, J. C., Murray, J., Ma, M., Martin, E., Rosenthal, D. N., Almond, C. S. ELSEVIER SCIENCE INC. 2022: S521-S522
  • Size Matching by Height, Body Surface Area, and Body Mass Index in Infant Heart Transplantation Lee, J., Kidambi, S., Rosenthal, D. N., Dykes, J. C., Ma, M. ELSEVIER SCIENCE INC. 2022: S53
  • Towards identifying predictors of pediatric heart only versus combined heart liver transplantation Zhang, K., Chen, S., Syed, A., Gallo, A., Esquivel, C., Bonham, A., Hollander, S. A., Ma, M., Han, J., Ebel, N. H. WILEY. 2022
  • Virtual Transcatheter Interventions for Peripheral Pulmonary Artery Stenosis in Williams and Alagille Syndromes. Journal of the American Heart Association Lan, I. S., Yang, W., Feinstein, J. A., Kreutzer, J., Collins, R. T., Ma, M., Adamson, G. T., Marsden, A. L. 2022: e023532


    Background Despite favorable outcomes of surgical pulmonary artery (PA) reconstruction, isolated proximal stenting of the central PAs is common clinical practice for patients with peripheral PA stenosis in association with Williams and Alagille syndromes. Given the technical challenges of PA reconstruction and the morbidities associated with transcatheter interventions, the hemodynamic consequences of all treatment strategies must be rigorously assessed. Our study aims to model, assess, and predict hemodynamic outcomes of transcatheter interventions in these patients. Methods and Results Isolated proximal and "extensive" interventions (stenting and/or balloon angioplasty of proximal and lobar vessels) were performed in silico on 6 patient-specific PA models. Autoregulatory adaptation of the cardiac output and downstream arterial resistance was modeled in response to intervention-induced hemodynamic perturbations. Postintervention computational fluid dynamics predictions were validated in 2 stented patients and quantitatively assessed in 4 surgical patients. Our computational methods accurately predicted postinterventional PA pressures, the primary indicators of success for treatment of peripheral PA stenosis. Proximal and extensive treatment achieved median reductions of 14% and 40% in main PA systolic pressure, 27% and 56% in pulmonary vascular resistance, and 10% and 45% in right ventricular stroke work, respectively. Conclusions In patients with Williams and Alagille syndromes, extensive transcatheter intervention is required to sufficiently reduce PA pressures and right ventricular stroke work. Transcatheter therapy was shown to be ineffective for long-segment stenosis and pales hemodynamically in comparison with published outcomes of surgical reconstruction. Regardless of the chosen strategy, a virtual treatment planning platform could identify lesions most critical for optimizing right ventricular afterload.

    View details for DOI 10.1161/JAHA.121.023532

    View details for PubMedID 35253446

  • Airway Characteristics of Patients With 22q11 Deletion Undergoing Pulmonary Artery Reconstruction Surgery: Retrospective Cohort Study. Pediatric critical care medicine : a journal of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies Sganga, D., Meister, K., Sidell, D. R., Wise-Faberowski, L., Shek, J., Ma, M., Martin, E., Hanley, F. L., McElhinney, D., Asija, R. 2022


    OBJECTIVES: We have previously shown that patients with a chromosome 22q11 microdeletion are at risk for prolonged respiratory failure after pulmonary artery reconstruction surgery compared with those with normal genotype. We sought to describe preexisting airway abnormalities in this patient population and examine relationships between airway abnormalities and outcomes.DESIGN: Single-center retrospective chart review from Society of Thoracic Surgery and Pediatric Cardiac Critical Care Consortium databases and the electronic medical record.SETTING: Lucile Packard Children's Hospital at Stanford from September 2017 to February 2019.PATIENTS: All patients undergoing pulmonary artery reconstruction surgery were considered for inclusion.INTERVENTIONS: We identified 127 patients meeting study inclusion criteria. Thirty-nine patients met specific criteria and underwent screening preoperative bronchoscopy including microdirect laryngoscopy and lower airway examination. Postoperative bronchoscopy was performed at the discretion of the intensive care team.MEASUREMENTS AND MAIN RESULTS: Airway abnormalities were detected in 25/26 of children (96%) with a chromosome 22q11 deletion who underwent preoperative bronchoscopy. Upper and lower airway pathologies were found in 19/25 (73%) and 21/25 (81%) patients, respectively, and it was common for patients to have more than one abnormality. Presence of 22q11 deletion was associated with longer duration of mechanical ventilation (9.1 vs 4.3 d; p = 0.001), use of noninvasive positive pressure support (13 vs 6 d; p = 0.001), and longer hospital stays (30 vs 14 d; p = 0.002). These outcomes were worse when compared with patients with known airway abnormalities who did not have 22q11 deletion.CONCLUSIONS: Preexisting upper and lower airway pathologies are common in patients with a chromosome 22q11 deletion who undergo pulmonary artery reconstruction surgery. Despite similar postoperative hemodynamics and outcomes as their counterparts without 22q11 deletion, 22q11 deletion is associated with more postoperative respiratory complications not entirely explained by preexisting airway abnormalities.

    View details for DOI 10.1097/PCC.0000000000002921

    View details for PubMedID 35213412

  • Commentary: A new Fontan commandment. The Journal of thoracic and cardiovascular surgery Ma, M. 2022

    View details for DOI 10.1016/j.jtcvs.2022.01.008

    View details for PubMedID 35125211

  • Neurologic complications in en bloc pediatric heart-liver transplants Pan, J., Bensen, R., Ebel, N., Mendoza, J., Ma, M., Hollander, S., Gallo, A., Esquivel, C., Bonham, A. WILEY. 2022: 80
  • Implantable Cardioverter Defibrillators in Infants and Toddlers: Indications, Placement, Programming, and Outcomes. Circulation. Arrhythmia and electrophysiology Zahedivash, A., Hanisch, D., Dubin, A. M., Trela, A., Chubb, H., Motonaga, K., Goodyer, W., Maeda, K., Reinhartz, O., Ma, M., Martin, E., Ceresnak, S. 2022: CIRCEP121010557


    Limited data exist regarding implantable cardioverter defibrillator (ICD) usage in infants and toddlers. This study evaluates ICD placement indications, procedural techniques, programming strategies, and outcomes of ICDs in infants and toddlers.This is a single-center retrospective review of all patients ≤3 years old who received an ICD from 2009 to 2021.Fifteen patients received an ICD at an age of 1.2 years (interquartile range [IQR], 0.1-2.4; 12 [80%] women; weight, 8.2 kg [IQR, 4.2-12.6]) and were followed for a median of 4.28 years (IQR, 1.40-5.53) or 64.2 patient-years. ICDs were placed for secondary prevention in 12 patients (80%). Diagnoses included 8 long-QT syndromes (53%), 4 idiopathic ventricular tachycardias/ventricular fibrillations (VFs; 27%), 1 recurrent ventricular tachycardia with cardiomyopathy (7%), 1 VF with left ventricular noncompaction (7%), and 1 catecholaminergic polymorphic ventricular tachycardia (7%). All implants were epicardial, with a coil in the pericardial space. Intraoperative defibrillation safety testing was attempted in 11 patients (73%), with VF induced in 8 (53%). Successful restoration of sinus rhythm was achieved in all tested patients with a median of 9 (IQR, 7.3-11.3) J or 0.90 (IQR, 0.68-1.04) J/kg. Complications consisted of 1 postoperative chylothorax and 3 episodes of feeding intolerance. VF detection was programmed to 250 (IQR, 240-250) ms with first shock delivering 10 (IQR, 5-15) J or 1.1 (IQR, 0.8-1.4) J/kg. Three patients (20%) received appropriate shocks for ventricular tachycardia/VF. No patient received an inappropriate shock. There were 2 (13%) ventricular lead fractures (at 2.6 and 4.2 years post-implant), 1 (7%) pocket-site infection, and 2 (13%) generator exchanges. All patients were alive, and 1 patient (7%) received a heart transplant.ICDs can be safely and effectively placed for sudden death prevention in infants and toddlers with good midterm outcomes.

    View details for DOI 10.1161/CIRCEP.121.010557

    View details for PubMedID 35089800

  • Ultrarapid Nanopore Genome Sequencing in a Critical Care Setting. The New England journal of medicine Gorzynski, J. E., Goenka, S. D., Shafin, K., Jensen, T. D., Fisk, D. G., Grove, M. E., Spiteri, E., Pesout, T., Monlong, J., Baid, G., Bernstein, J. A., Ceresnak, S., Chang, P. C., Christle, J. W., Chubb, H., Dalton, K. P., Dunn, K., Garalde, D. R., Guillory, J., Knowles, J. W., Kolesnikov, A., Ma, M., Moscarello, T., Nattestad, M., Perez, M., Ruzhnikov, M. R., Samadi, M., Setia, A., Wright, C., Wusthoff, C. J., Xiong, K., Zhu, T., Jain, M., Sedlazeck, F. J., Carroll, A., Paten, B., Ashley, E. A. 2022

    View details for DOI 10.1056/NEJMc2112090

    View details for PubMedID 35020984

  • Commentary: The hardest part of cardiothoracic surgery is getting to do it. The Journal of thoracic and cardiovascular surgery Ma, M. 1800

    View details for DOI 10.1016/j.jtcvs.2021.12.040

    View details for PubMedID 35012782