Ventricular assist devices as a bridge to heart transplantation or as destination therapy in pediatric patients

Purpose: Despite the remarkable advances with the use of ventricular assist devices (VAD) in adults, pneumatic pulsatile support in children is still limited. We report on our experience in the pediatric population.

Methods: Retrospective review of 27 consecutive children offered mechanical support with Berlin Heart as a bridge to heart transplant, and Jarvik 2000 as a destination therapy from February 2002 to October 2011.

Results: The median patient age was 4.8 years (range = 75 days to 20.5 years). The median patient weight was 18.6 kg (range = 2.9-63 kg). We divided the patients in two groups, including in group I patients assisted for bridging to heart transplantation and in group II patients with Duchenne's dystrophy assisted as destination therapy. In the group I, 11 patients required biventricular mechanical support (BVAD), but in all other cases, a single left VAD proved sufficient (56%). The median duration of VAD support was 48 days (1 to 192 days). The median pre-VAD pulmonary vascular resistance index (Rpi) was 5.7 WU/m(2) (3.5 to 14.4 WU/m(2)). Twelve patients (48%) were successfully bridged to heart transplantation after a median duration of mechanical support of 63 days (range = 2-168 days). Ten deaths occurred (40%), three for neurological complications, two for sepsis, two for multiorgan failure, and three other for device malfunctioning. Since 2007, the survival rate of our patients has increased from 33% to 75%, and the need for BVAD has decreased from 89% to 23%. In the group II, two patients with mean age of 15.3 years were assisted with Jarvik 2000, and both of them are alive in a follow-up of 10.4 months. In two patients with Rpi > 10 WU/m(2), unresponsive to pulmonary vasodilatator therapy, Rpi dropped to 2.2 and 2 WU/m(2) after 40 and 23 days of BVAD support, respectively. Six patients (32%) required at least one pump change. Of 12 patients undergoing heart transplantation, five developed an extremely elevated (>60%) panel-reactive antibody by enzyme-linked immunosorbent assay, confirmed by Luminex. All of them experienced at least one acute episode of rejection in the first month after heart transplant, needing plasmapheresis. The survival rate after heart transplantation was 100% with a median follow-up of 34.4 months (45 days to 8.7 years).

Conclusions: Mechanical support in children with end-stage heart failure is an effective strategy as a bridge to heart transplantation with a reasonable morbidity and mortality. BVAD support may offer an additional means to reverse extremely elevated pulmonary vascular resistance. The total implantable system opens a future scenarios for patients not eligible for heart transplantation.