Early Clinical Experience of a Novel Mobile Driving Unit for Pediatric VAD Support

Abstract

Purpose Recently, a novel mobile driving unit (MDU) of the only approved pediatric ventricular assist device (VAD) system for both short- and long-term support of children of all sizes and ages received market approval. The MDU was specifically developed to improve mobility and autonomy of children supported with this paracorporeal (pc) VAD. This case series collects initial information with the aim to assess the first clinical experience. Methods A retrospective case series gathered anonymized patient health data of pediatric patients supported with MDU. The usability was assessed by means of a patient standardized questionnaire (numerical scale, 1= worst to 5= best). Results From February 2020 until September 2020, eight children (3 females) have been supported with a pc VAD in combination with the MDU. The median age was 1.4 years (range 0.5 - 7.5), median body surface area 0.4 m2 (0.3 - 0.9). Primary diagnosis was cardiomyopathy (CM) in 7 patients (5 dilated and 2 restrictive CM), and congenital heart disease in one child. Five patients (62.5%) received a pc VAD as left-sided and two patients as biventricular support (BVAD, 25%). One had a secondary right-sided pc VAD in combination with an implantable left-sided centrifugal VAD. The distribution of pc pump chambers by size was 10 ml pump: 2 patients (25%), 15 ml pump: 4 subjects (50%) and 30 ml pump: 2 children (25%), plus 15 ml pumps in both pc BVAD patients. The mean time of VAD support was 406 ± 241 days, with 148 ± 76 days on MDU. At the end of the observational period, 5 patients (62.5%) were still on system, 2 (25%) were transplanted and 1 died (12.5%) for causes not related to the driving unit. The survey found increased mobility (score 4.2/5), enlarged activity radius (5/5) and reduced noise nuisance (4.5/5) with MDU in comparison to the stationary unit. There were no complaints in MDU handling reported and the easiness to use was rated (4.5/5). In addition the parents reported a significant less heat generation by the MDU. The safety profile of MDU showed five adverse events: one fatal case (12.5%), one respiratory failure (12.5%), both not device-related, and two pump malfunctions (25%). One patient (12.5%) underwent pump replacement due to fibrin debris. Conclusion The case series suggests that the novel MDU is safe and effective for VAD support in the pediatric population. It is likely that MDU will increase the quality of life in this cohort.