Incremental Value of Global Longitudinal Strain to Michigan Risk Score and Pulmonary Artery Pulsatility Index in Predicting Right Ventricular Failure Following Left Ventricular Assist Devices.

Abstract

The incremental utility of right ventricular (RV) strain on predicting right ventricular failure (RVF) following left ventricular assist device (LVAD) implantation, beyond clinical and haemodynamic indices, is not clear. Two hundred and forty-six (246) patients undergoing LVAD implantation, who had transthoracic echocardiograms pre and post LVAD, pulmonary artery pulsatility index (PAPI) measurements and Michigan risk score, were included. We analysed RV global longitudinal strain (GLS) using speckle tracking echocardiography. RVF following LVAD implantation was defined as the need for medical support for >14 days, or unplanned RV assist device insertion after LVAD implantation. Mean preoperative RV-GLS was -7.8±2.8%. Among all, 27% developed postoperative RVF. A classification and regression tree analysis identified preoperative Michigan risk score, PAPI and RV-GLS as important parameters in predicting postoperative RVF. Eighty per cent (80%) of patients with PAPI <2.1 developed postoperative RVF, while only 4% of patients with PAPI >6.8 developed RVF. For patients with a PAPI of 2.1-3.2, having baseline Michigan risk score >2 points conferred an 81% probability of subsequent RVF. For patients with a PAPI of 3.3-6.8, having baseline RV-GLS of -4.9% or better conferred an 86% probability of no subsequent RVF. The sensitivity and specificity of this algorithm for predicting postoperative RVF were 67% and 93%, respectively, with an area under the curve of 0.87. RV-GLS has an incremental role in predicting the development of RVF post-LVAD implantation, even after controlling for clinical and haemodynamic parameters.