The development of aortic insufficiency in continuous-flow left ventricular assist device-supported patients.

Abstract

Significant aortic insufficiency (AI) after left ventricular assist device (LVAD) placement affects device performance and end-organ perfusion. This study examined the development and progression of AI after implantation of continuous-flow LVAD. Seventy-nine patients undergoing Heart Mate II (Thoratec Corp, Pleasanton, CA) LVAD implantation for predominantly destination therapy (n = 69 [87%]) were examined. Preoperative and postoperative echocardiograms for all patients were reviewed at the intervals of 0 to 3, 3 to 6, 6 to 12, 12 to 18, and 18 to 24 months. AI was graded on an interval scale of 0, none; 0.5, trivial; 1, mild; 1.5, mild to moderate; 2, moderate; 2.5, moderate to severe; and 3, severe. Development and progression of AI were analyzed. The incidence of significant AI (mild or greater) was 52% (n = 41). Median time to AI development was 187 days. The median duration of VAD support was 761 days. Mild AI developed in 41 patients (52%). No severe AI developed. In the Cox regression model (hazard ratio [95% confidence interval]), aortic valve closure (2.51 [1.06 to 5.89]; p = 0.03), and age (1.04 [1.008 to 1.08]; p = 0.01) were independent predictors of AI development. There was no difference in mortality rates in the two groups (p = 0.40 by log-rank test). A mixed-model linear regression analysis showed a significant overall progression of AI over time (β ± standard error, 0.06 ± 0.02; p = 0.006). AI develops over time in a significant number of Heart Mate II LVAD patients. AI is more common in patients with closed aortic valves and in the older age group. As more patients require long-term VAD support, the development of AI will need careful attention and monitoring.