CARC11: Outcomes of outflow graft stenting in HeartMate 3 left ventricular assist devices: A systematic review

Abstract

Background: Outflow graft stenosis in continuous-flow left ventricular assist devices (CF-LVAD) is multifactorial. We sought to pool the existing evidence on indications, utilization patterns, and outcomes of transcatheter interventions for outflow graft stenosis in the HeartMate 3 (HM 3) LVAD. Methods: An electronic search was performed to identify all studies in the English literature reporting on HM 3 LVAD outflow graft stenting. Sixteen published reports and one unpublished case comprising a total of 28 patients were included. Patient-level data were extracted for analysis. Results: Median patient age was 68.5 years [Interquartile range: 58, 71] and 25.9% (7/27) were female. Dyspnea [60.7% (17/28)] was the most common presenting symptom. Low flow alarms were present in 60% (15/25) of patients, of which 20% (3/15) did not report other symptoms. LVAD findings included external compression [35.7 % (10/28)], graft twist [21.4% (6/28)], graft twist and external compression [14.3% (4.28)], intravascular thrombus [10.7% (3/28)], graft twist and intravascular thrombus [3.6% (1/28)], and pseudoaneurysm of outflow graft [3.6% (1/28)]. Median time from LVAD implantation to stenting was 2.1 years [1.4, 3] with 35.7% (10/28) receiving two stents and 14.3% (4/28) receiving >2 stents. Immediate flow normalization after stenting was observed in 85.7% (24/28). Recurrent stenosis was observed in 8% (2/25). Other complications included neurological events [8% (2/25)], recurrent low flow alarms [8% (2/25)], and severe right ventricular failure [8% (2/25)]. Heart transplantation was performed in 8% (2/25) after stenting. The 30-day mortality was 12% (3/25). Overall mortality was also 12% (3/25) at a median follow-up of 3.9 months [1, 17]. Conclusion: Outflow graft stenting in HM 3 LVAD appears to be a reasonable treatment option for outflow graft stenosis with low overall rate of complications and mortality. Further refinement of indications and approach may improve outcomes.