Preoperative higher right ventricular stroke work index increases the risk of de novo aortic insufficiency after continuous-flow left ventricular assist device implantation.

Abstract

During continuous-flow left ventricular assist device (CF-LVAD) support, hemodynamic shear stress causes a burden on aortic valve (AV) leaflets, leading to de novo aortic insufficiency (AI). This study investigated the influence of preoperative hemodynamic parameters on de novo AI in CF-LVAD recipients. We reviewed 125 patients who underwent CF-LVAD implantation without concomitant AV surgery between 2005 and 2018. De novo AI was defined as moderate or severe AI in those with none or trivial preoperative AI. During mean 30 ± 16 months of CF-LVAD support, de novo AI-free rate was 86% and 67% at 1 and 2 years, respectively. Multivariable analysis showed that higher right ventricular stroke work index (RVSWI) (hazard ratio, 1.12 /g/m²/beat; 95% confidence interval, 1.00-1.20; p = 0.047) and trivial grade AI (hazard ratio, 2.8; 95% confidence interval, 1.2-6.4; p = 0.020) were independent preoperative risk factors for de novo AI. The longitudinal analysis using generalized mixed effects model showed that higher RVSWI was associated with continuous AV closure after LVAD implantation (Odd ratio, 1.20/g/m²/beat; 95% confidence interval, 1.00-1.43 /g/m²/beat; p = 0.047). Right heart catheterization revealed that preoperative RVSWI was positively correlated with postoperative pump flow index in patients with continuously closed AV (r = 0.44, p = 0.04, n = 22). Preoperative higher RVSWI was a significant risk factor for de novo AI following CF-LVAD implantation. In patients with preserved right ventricular function, postoperative higher pump flow may affect AI development via hemodynamic stress on the AV.