Clinical Outcomes of Ventricular Assist Device for Failing Bidirectional Glenn Physiology

Purpose The number of patients with failing single ventricle physiology is increasing, and ventricular assist device (VAD) support in this population is challenging. The purpose of this study was to describe our clinical experience with VAD for failing Glenn physiology. Methods A retrospective review of clinical outcomes was conducted in patients that underwent durable VAD placement for failing Glenn circulation between 2010 and 2020 at Texas Children's Hospital. Results Ten patients met inclusion criteria; all had a morphologic right ventricle (RV): 6 hypoplastic left heart syndrome/variant and 4 with isomerism with RV dominant atrioventricular septal defect. INTERMACS profiles were 1 in 3 patients (1 with ECMO) and 2 in 7 patients. Four patients were intubated. Age, weight, and body surface area at VAD implantation were 3.2 (0.9-10.1) years, 13.0 (7.7-22.8) kg, and 0.50 (0.36-0.90) m2, respectively. The device-strategy included HVAD in 6, Jarvik 2015 in 1, and Berlin cannula (with Berlin and/or Rotaflow pumps) in 3. Concomitant Fontan completion was performed in 5 patients (1 with fenestration), while the other 5 remained with Glenn circulation. PaO2/FiO2 ratio (median, range) on postoperative day 1 was significantly higher with Fontan completion [192 (53-336)] than without [76 (59-78), p=0.05] except a patient with Glenn circulation on ECMO. The median duration of mechanical ventilation after VAD was 2 days (range, 1 - 14). There was 1 early mortality 8 days after HVAD placement with Fontan completion due to neurologic insult intraoperatively. The remaining 9 patients (90%) were bridged to transplant at a median support duration of 3.8 (0.1-16.6) months. Five of the 6 HVAD patients were able to be discharged home prior to transplant. One patient encountered a pump thrombus requiring pump exchange and 1 patient suffered a thromboembolic stroke due to a mobile intraventricular thrombus. One patient had a subdural and subarachnoid hemorrhage 27 days after VAD implantation, with complete neurologic recovery without deficits. Conclusion This single-institutional experience suggests long term VAD support is sustainable for failing Glenn physiology with accompanying Fontan completion in selected patients. Further studies are warranted to optimize long term VAD support in this challenging population.