Pre-Operative Velocity Vector Imaging To Predict the Need for Right Ventricular Support in Patients Undergoing Left Ventricular Assist Device Implantation

Abstract

<h3>Purpose</h3> The aim of this study was to predict right ventricular (RV) dysfunction after left ventricular assist device (LVAD) implant by preoperative assessment of RV global myocardial systolic strain and strain rate using velocity vector imaging. Novel 2D echo parameters may prove useful in preoperatively identifying patients at high risk for RV dysfunction post LVAD implant. <h3>Methods and Materials</h3> Between Jan 1^st 2010 and Dec 31^st 2011, 39 consecutive patients who received a HeartMate II LVAD underwent a pre-operative 2D ECHO. The RV systolic myocardial longitudinal velocity, strain and strain rate were measured using dynamic 2D vector velocity imaging as markers of RV performance. The primary endpoint was death or implant of a RV assist device (RVAD) due to acute RV failure within 6 months after LVAD implant. <h3>Results</h3> RV failure occurred in 25 of 39 patients (64%) after LVAD placement. Despite inotropic support, inhaled nitric oxide and RVAD support 11 patients of the 25 who developed RV failure expired. A preoperative RV global systolic myocardial strain cut off of -3% had a sensitivity of 73% and a specificity of 86% in predicting post LVAD implant RV failure. RV global strain was an independent predictor of RV failure in a multivariate model (including RV free wall strain, mean PAP, RV EF and Michigan score) (AUC was 0.81). [figure 1] <h3>Conclusions</h3> Poor intrinsic RV myocardial function is associated with a higher mortality in LVAD patients. Dimensionless RV parameters, derived from 2-dimensional speckle tracing echocardiography imaging, particularly, peak systolic global RV strain appears to be promising in predicting LVAD patients who require RVAD.