Left Atrial Inflow Ventricular Assist Device Utilization in Patients With Small or Restrictive Left Ventricles: A Systematic Review

Background Conventional mechanical circulatory support offers limited options for patients with small or restrictive left ventricles. Left atrial inflow (LA–Ao) ventricular assist device (VAD) configuration represents an alternative to conventional apical left ventricular assist device (LVAD). However, outcomes data remain limited. To address this, we evaluated patient characteristics, procedural details, and outcomes of LA–Ao VAD configuration in this population. Methods A systematic search was conducted to identify case reports and series of patients with small or restrictive left ventricles who underwent LA–Ao LVAD implantation. A total of 21 reports, representing 27 patients, were included. Patient‐level data were extracted for analysis. Results Thirteen adult and 14 pediatric patients underwent LA–Ao VAD implantation. Median age was 57 [46–62] years in adults and 3.5 [0.8–9] years in children. Hypertrophic cardiomyopathy and restrictive cardiomyopathy were the predominant diagnoses in both adults and children, accounting for 54% (7/13) and 29% (4/14), and 46% (6/13) and 43% (6/14), respectively. Median left ventricular ejection fraction was 44% [39–53] in adults and 45% [36–61] in children, and median left ventricular end‐diastolic diameter was 42 [35–42] mm in adults and 33 [29–34] mm in children. The most used devices were HeartWare HVAD (46%, 6/13) in adults, and Berlin Heart (64%, 9/14) in children. Overall pulmonary capillary wedge pressure decreased from 23 [19–27] to 7 [0–9] mmHg ( p = 0.02), and cardiac index increased from 2.0 [1.3–2.8] to 3.1 [2.7–3.7] L/min/m 2 ( p = 0.04). In‐hospital mortality included one fatal case (7.7%) in each group. Overall survival was 85% (11/13) in adults at median follow‐up of 6.7 [4.4–19.9] months and 86% (12/14) in children at 2.3 [1.2–8.1] months. Conclusion The LA–Ao configuration of VAD is a viable strategy for mechanical circulatory support in patients with small or restrictive left ventricles. It offers effective unloading of the left atrium and improved cardiac index, supporting its role as an alternative to the conventional LVAD approach.