Impact of Ventricular Stroke Work Indices on Mortality in Heart Failure Patients After Percutaneous Mitral Valve Repair.

Abstract Optimal patient selection for transcatheter mitral valve repair (TMVR) remains challenging. The aim of the study was to assess the impact of left and right ventricular stroke work index (LVSWi, RVSWi) on mortality in patients with chronic heart failure (CHF) undergoing TMVR. 140 patients (median age 74±9.9 years, 67.9% male) with CHF who underwent successful TMVR were included. Primary endpoint was defined as all-cause mortality after 16±9 months of follow-up. LVSWi was calculated as: Stroke volume index (SVi) * (mean arterial pressure – postcapillary wedge pressure) * 0.0136 = g/m−1/m2. RVSWi was calculated as: SVi * (mean pulmonary artery pressure – right atrial pressure) * 0.0136 = g/m−1/m2. Receiver operating characteristic (ROC) analysis determined an optimal threshold of 24.8 g/m−1/m2 for LVSWi (sensitivity 80.4%, specificity 40.2%, area under the curve (AUC) 0.71 [0.60-0.81]; p=0.001) and 8.3 g/m−1/m2 for RVSWi (sensitivity 67.4%, specificity 57.0%, AUC 0.67 [0.56-0.78]; p=0.006), respectively. Kaplan-Meier analysis showed significantly lower survival in patients with LVSWi ≤24.8 g/m−1/m2 (20.0% vs. 39.4%; log-rank p=0.038) and in patients with RVSWi ≤8.3 g/m−1/m2 (22.1% vs. 43.7%; log-rank p=0.026), respectively. LVSWi of ≤24.8 g/m−1/m2 and RVSWi of ≤8.3 g/m−1/m2 were independent predictors for all-cause mortality (hazard ratio (HR) 2.83; 95% confidence interval (CI) 1.1 to 7.6; p=0.04; HR 2.52; 95% CI 1.04 to 6.1; p=0.041). A risk-score incorporating LVSWi and RVSWi cut-off values from ROC analysis powerfully predicts long-term survival after successful TMVR (log-rank p=0.02). In conclusion, LVSWi and RVSWi independently predict mortality in patients with CHF undergoing TMVR and might be useful in risk stratification of TMVR candidates.