Fetal cardiac intervention: Improved results of fetal cardiac bypass in immature fetuses using the TinyPump device.
journal of thoracic and cardiovascular surgery
2013; 145 (6): 1460-1464
Intermediate-term outcomes after combined heart-liver transplantation in children with a univentricular heart
JOURNAL OF HEART AND LUNG TRANSPLANTATION
2013; 32 (3): 368-370
Fetal cardiac surgery is a potential innovative treatment for certain congenital heart defects that have significant mortality and morbidity in utero or after birth, but it has been limited by placental dysfunction after fetal cardiac bypass. We have used the TinyPump device for fetal cardiac bypass in sheep fetuses at 90 to 110 days gestation.Ten mixed-breed pregnant ewes were used over a period of 6 months, and 10 fetuses were placed on bypass for 30 minutes. Five fetuses with a mean gestational age of 104 ± 4.5 days and mean weight of 1.4 ± 0.4 kg were placed on bypass using the TinyPump device, and 5 fetuses with a mean gestational age of 119 ± 4.5 days and mean weight of 3.4 ± 0.4 kg were placed on bypass using the roller head pump. The fetuses were monitored for up to 3 hours after bypass or until earlier demise.Progressive respiratory and metabolic acidosis developed in all fetuses. The TinyPump group had a lower gestational age and weight compared with the roller head pump group. However, the rate of postbypass deterioration in the TinyPump group, as measured with blood gases, was noted to be significantly slower compared with the roller head pump group.We demonstrate the feasibility of the TinyPump device for fetal cardiac bypass in a fetal sheep model. The TinyPump group showed improved results compared with the roller head group despite more immature fetuses. The TinyPump device seems to be a promising device for future studies of fetal cardiac bypass in immature fetal sheep and in primates.
View details for DOI 10.1016/j.jtcvs.2012.08.014
View details for PubMedID 22944083
Midterm Results of the Modified Ross/Konno Procedure in Neonates and Infants
ANNALS OF THORACIC SURGERY
2012; 94 (1): 156-163
For patients with end-stage hepatic failure secondary to failing hemodynamics, combined heart-liver transplant (H-LT) remains the only option for long-term survival. We report a series of three pediatric patients who successfully underwent orthotopic H-LT for failed single-ventricle palliation. All three patients are currently living, now two, three, and five years post-transplant, and remain completely free of cardiac cellular allograft rejection despite reduced immunosuppression protocols. One patient, however, did develop acute antibody-mediated rejection in the immediate post-transplant period, suggesting that this protective effect may be less effective in attenuating humoral mechanisms of rejection.
View details for DOI 10.1016/j.healun.2012.11.023
View details for Web of Science ID 000315664600014
View details for PubMedID 23415318
Pediatric combined heart-liver transplantation performed en bloc: A single-center experience
2012; 16 (4): 392-397
The management of congenital aortic stenosis in neonates and infants continues to be a surgical challenge. We have performed the modified Ross-Konno procedure for patients who have severe aortic insufficiency or significant residual stenosis after balloon aortic dilation. The midterm results of this procedure were evaluated in this subset of patients.Between 1994 and 2010, a total of 24 patients younger than 1 year of age underwent the modified Ross-Konno procedure. The diagnoses were aortic stenosis with or without subaortic stenosis (n = 16), Shone's complex (n = 7), and interrupted aortic arch with subaortic stenosis (n = 1). The aortic root was replaced with a pulmonary autograft, and the left ventricular outflow tract (LVOT) was enlarged with a right ventricular infundibular free wall muscular extension harvested with the autograft.Age at operation ranged from 1 to 236 days (median 28 days). The median follow-up period was 81 months (range 1-173 months). There was 1 early death and no late mortality. Overall the 1-, 2-, and 5-year survival rate was 95% ± 4.5%. Freedom from aortic stenosis was 94.7% ± 5.1% at 1, 2, and 5 years. Less than mild aortic insufficiency was 93.3% ± 6.4% at 2 years, and 74.7% ± 12.9% at 5 years. In total, 23 reoperations and reinterventions were performed; 14 were allograft conduit replacements. Two patients required aortic valve plasty. None required valve replacement. The reintervention-free rate was 64.6% ± 10.8% at 2 years and 36.9% ± 11.3% at 5 years.Pulmonary autografts demonstrated good durability with low mortality and morbidity. This study shows that the modified Ross-Konno procedure can be a practical choice in selective cases for complex LVOT stenosis in neonates and infants.
View details for DOI 10.1016/j.athoracsur.2012.03.007
View details for Web of Science ID 000305801600033
View details for PubMedID 22626750
Use of the Impella 5.0 as a bridge from ECMO to implantation of the HeartMate II left ventricular assist device in a pediatric patient
2012; 16 (2): 205-206
Recovery During Mid-Term Mechanical Support of Fontan Circulation in Sheep
2009; 55 (4): 406-411
Pediatric CHLT is rarely performed in transplant centers and even fewer are performed en bloc. In the hands of an experienced surgeon with the appropriate patient selection, CHLT performed en bloc may have several operative and immunologic benefits, thereby resulting in improved outcomes for the transplant recipient. A single-institutional, retrospective review from 1/1/06 to 12/31/10 was conducted. Three pediatric patients with end-stage heart and liver disease who were considered low immunologic risk were included. All were managed by the same surgeon with a herein-described CHLT donor and recipient operation. Data were collected on patient and graft survival, rejection episodes, infectious complications, operative time, intraoperative transfusion requirements, and immunosuppression regimens. One-yr patient and graft survival rates were 100%. No patients experienced antibody-mediated or cell-mediated rejection. No patients had postoperative infections, and all patients were free of opportunistic infections at one-yr post-transplant. All patients were maintained safely on steroid-free immunosuppression. There were no intraoperative complications. In pediatric end-stage heart and liver disease patients with low immunologic risk, it is reasonable to proceed with en bloc CHLT so long as there is an experienced surgeon to perform the case. This offers operative and immunologic advantages to the recipient while maintaining equivalent, if not improved, recipient and graft outcomes.
View details for DOI 10.1111/j.1399-3046.2012.01695.x
View details for Web of Science ID 000303998800024
View details for PubMedID 22583978
Total cavopulmonary connection (CPC) has a significant incidence of late failure due to increased systemic venous pressure and low cardiac output. Mechanical support could prevent failure by correcting hemodynamics. We established a model of inferior CPC using an axial flow pump (Thoratec HeartMate II, Thoratec Corp. Pleasanton, CA) in a group of ten 47-57 kg sheep and assessed hemodynamics and metabolism as a potential chronic treatment option for failed Fontan circulation. After pilot studies (n = 7), three animals underwent pump-supported inferior CPC to assess hemodynamic and metabolic responses. Pump inflow was connected to the inferior vena cava (IVC) and outflow to the main pulmonary artery. The IVC was ligated at the right atrium. Hemodynamic and biochemical parameters were recorded over four days. The first seven animals died from pump-related causes (graft kinking, three; pump thrombosis, one) or other causes (GI bleeding, one; suspected stroke, two). The subsequent three animals were electively euthanized on postoperative day four due to IRB requirements. Over the four day postoperative period, pump flow was 3.43 +/- 0.62 L/min and IVC pressure 4.05 +/- 3.21 mm Hg (mean +/- SD). Lactate levels remained normal. Low pressure and high-volume IVC flow was sustained by mechanical support. We will next attempt chronic pump implantation.
View details for DOI 10.1097/MAT.0b013e3181a0a570
View details for Web of Science ID 000267559100016
View details for PubMedID 19471161