Mechanical bridging to orthotopic heart transplantation in children weighing less than 10kg: feasibility and limitations

Abstract

Infants and young children are considered the most difficult group to bridge to orthotopic heart transplantation (OHT) and data regarding outcomes are scarce. We reviewed our patients ≤ 10 kg with those who were bridged to OHT using ventricular assist device (VAD) Berlin Heart (BH) Excor ± extracorporeal membrane oxygenation (ECMO) between 2004 and 2009. Eleven children ≤ 10 kg with end-stage heart failure (cardiomyopathy or myocarditis) were treated with VAD as bridge to OHT: the median weight was 8.0 (range 3.9-10.0 kg)kg and median age was 12.3 (range 1.2-33.9 months) months. Five (45%) required ECMO support pre-BH and six were on mechanical ventilation and inotropes. In 9/11 (82%), the support mode was left ventricular assist device (L-VAD) (all alive): one of two patients needing Bi-VAD support died. On BH, the median support time was 27 days and time to extubation was 8 days. Two out of 11 (18%) suffered strokes confirmed on brain imaging; both recovered and one underwent resection of infarcted small bowel. Ten out of 11 (91%) were transplanted, one remains in hospital and nine are at home in good health. When compared to patients >10 kg bridged with BH (n = 15), the mortality (p = 0.51) and rates of neurological complications (p = 0.54) were similar. Post-transplant recovery (ventilation times and time to home discharge) was similar between the bridged children ≤ 10 kg and non-bridged children ≤ 10 kg who underwent OHT. Mechanical bridging to transplantation is clinically feasible in children ≤ 10 kg, achieving excellent outcomes. Judicious use of VADs in smaller children will optimise the use of donor organs; however, the effect on overall OHT waiting times, if mechanical bridging was extended to a large number of small children, is unknown.