Berlin Heart EXCOR Support in the First Year of Life: A Single Centre Experience.

BACKGROUND: Berlin Heart EXCOR Pediatric Ventricular Assist Device (BHE) (Berlin Heart AG, Berlin, Germany, BHE) is used worldwide for mechanical circulatory support as a bridge to transplantation or recovery for children with end-stage heart failure. The study aim was to evaluate morbidity and mortality of children less than one year old supported with BHE to identify predictors of adverse outcomes. METHODS: Data of all children aged less than one year supported with BHE between 2005 and 2018 at the Royal Children's Hospital, Melbourne were reviewed. Adverse events were defined using PediMACS criteria. RESULTS: Fourteen (14) children under 1 year of age were implanted with BHE at a median age and weight of 0.37 years (IQR 0.09-0.7) and 5.7 kg (IQR 3.5-7.95) respectively. Four (4) patients were neonates, and 10 were older infants. Twelve (12) patients had cardiomyopathy and two, myocarditis. Preoperative extracorporeal membrane oxygenation (ECMO) support was required in six patients for a mean of 9 days (IQR 6-13). Sepsis occurred in five patients (36%) and thromboembolic stroke in two patients (14%). Survival to bridge to transplantation (11) and recovery (1) was achieved in 12 patients (86%). Mortality was 14%. The median duration of BHE support was 110 days (IQR 40-161). Both patients who died were neonates with myocarditis and required surgical re-intervention during BHE support. CONCLUSIONS: BHE provides excellent support as a bridge to transplantation or recovery in infants, with a low incidence of neurological dysfunction. Neonates with myocarditis may be at greater risk for death after BHE implantation.

Transcatheter closure of the patent ductus arteriosus: an intention to treat analysis.

BACKGROUND: In patients with patent ductus arteriosus (PDA), transcatheter closure is the current procedure of choice. There are multiple devices available with limited current comparative data and varied recommendations for device selection. OBJECTIVE: To assess the efficacy and safety of the Flipper coil (FC) and the Amplatzer Duct Occluder (ADO). METHODS: An intention to treat analysis of all children admitted to the catheter laboratory at a single institution for occlusion of PDA from 2003 to 2011 was performed. Patient and device selection were determined by the treating physician. Standard techniques for FC and ADO implantation were used. RESULTS: Two hundred and twenty eight children with median weight of 14.2 kg (range; 5.5-68 kg) underwent cardiac catheterisation, with successful occlusion in 96.2% of patients when attempted. In 16 patients, median angiographic PDA diameter of 0.8 mm (range; 0.4-1.2 mm), was considered too small to warrant closure. Eight patients with large PDA's underwent surgical ligation. FC was successfully used in 70 (34.3%) and ADO in 134 (66.7%) patients. ADO patients were smaller (P=0.004) with larger PDA's (P<0.0001) than the FC group. Median fluoroscopy time was longer for ADO patients (10.1 min vs 8.0 min; P<0.0001). ADO had a lower embolisation rate (0% vs 6.6%; P=0.005) and a higher complete occlusion rate at follow-up (100% vs 73.4%; P<0.0001). Length of hospital admission decreased with time in both groups. CONCLUSION: Transcatheter closure of the PDA has a high degree of safety and efficacy. This study suggests that the ADO may be the device of first choice in the current era.

Safety and feasibility of adjunct autologous cord blood stem cell therapy during the Norwood heart operation.

BACKGROUND: We conducted this phase I, open-label safety and feasibility trial of autologous cord blood (CB) stem cell (CBSC) therapy via a novel blood cardioplegia-based intracoronary infusion technique during the Norwood procedure in neonates with an antenatal diagnosis of hypoplastic left heart syndrome (HLHS). CBSC therapy may support early cardiac remodeling with enhancement of right ventricle (RV) function during the critical interstage period. METHODS: Clinical grade CB mononucleated cells (CBMNCs) were processed to NetCord-FACT International Standards. To maximize yield, CBSCs were not isolated from CBMNCs. CBMNCs were stored at 4 °C (no cryopreservation) for use within 3 days and delivered after each cardioplegia dose (4 × 15 mL). RESULTS: Of 16 patients with antenatal diagnosis, 13 were recruited; of these 13 patients, 3 were not treated due to placental abruption (n = 1) or conditions delaying the Norwood for >4 days (n = 2) and 10 received 644.9 ± 134 × 106 CBMNCs, representing 1.5 ± 1.1 × 106 (CD34+) CBSCs. Interstage mortality was 30% (n = 3; on days 7, 25, and 62). None of the 36 serious adverse events (53% linked to 3 deaths) were related to CBMNC therapy. Cardiac magnetic resonance imaging before stage 2 (n = 5) found an RV mass index comparable to that in an exact-matched historical cohort (n = 22), with a mean RV ejection fraction of 66.2 ± 4.5% and mean indexed stroke volume of 47.4 ± 6.2 mL/m2 versus 53.5 ± 11.6% and 37.2 ± 10.3 mL/m2, respectively. All 7 survivors completed stage 2 and are alive with normal RV function (6 with ≤mild and 1 with moderate tricuspid regurgitation). CONCLUSIONS: This trial demonstrated that autologous CBMNCs delivered in large numbers without prior cryopreservation via a novel intracoronary infusion technique at cardioplegic arrest during Norwood palliation on days 2 to 3 of life is feasible and safe.

Bleeding and thrombotic events occur early in children on durable ventricular assist devices.

INTRODUCTION: Durable Ventricular Assist Devices (VADs) are increasingly used in children with end-stage heart failure. Major complications are bleeding and thromboembolism (TE). Our objective was to determine the timing, incidence and risk factors for bleeding and TE in children implanted with VADs. METHODS: This was a retrospective cohort of 8 years experience for children implanted with HeartWare HVAD and Berlin Heart EXCOR VADs at the Royal Children's Hospital, Melbourne. RESULTS: 44 patients were implanted with Berlin Heart EXCOR or HeartWare HVAD devices. Major bleeding occurred in 17 patients (39%), 7 (16%) experienced thromboembolic strokes, 13 (30%) required device exchange for TE, and 4 (9%) experienced arterial thromboembolism. Twenty-seven patients (61%) were transplanted, three (7%) recovered, and six (14%) remain on device when censored. Eight patients (18%) died on VAD, with leading causes being thromboembolic stroke and intracranial bleeding. The majority of bleeding events and thromboembolic events occurred while patients were on unfractionated heparin (bleeding 66%, TE 40.5%) or transitioning between heparin and warfarin (bleeding 22%, TE 38%). Majority of patients were on more than one antiplatelet agent at the time of a major bleeding (87%) or thromboembolic (89%) event. CONCLUSIONS: The majority of bleeding and TE events occurring in children supported with durable VADs occur when they are on unfractionated heparin or transitioning to warfarin. Modifications to anticoagulation and monitoring in the early post-operative periods should be a research focus.