Clin Res Cardiol (2022).

Role of cardiac power output at rest to predict mortality after transcatheter edge-to-edge-repair for severe mitral valve regurgitation
A. Ben Ammar1, R. Osteresch1, P. Dierks1, K. Diehl1, A. Fach1, J. Schmucker1, L. A. Mata Marín1, C. Frerker2, I. Eitel2, H. Wienbergen1, R. Hambrecht1
1Bremer Institut für Herz- und Kreislaufforschung (BIHKF), Bremen; 2Medizinische Klinik II / Kardiologie, Angiologie, Intensivmedizin, Universitätsklinikum Schleswig-Holstein, Lübeck;

Background: Cardiac power output at rest (CPO) is a known predictor of worse clinical outcome in various domains of heart failure (HF). However, the prognostic utility of CPO at rest in transcatheter edge-to-edge-repair (TEER) has never been tested.

Objective: To assess the impact of CPO at rest on mortality in chronic HF patients with severe mitral regurgitation (MR) undergoing TEER.

Consecutive patients with chronic HF (left ventricular systolic ejection fraction ≤ 50% from any cause) with severe MR who underwent TEER were included and followed prospectively. Primary endpoint was defined as all-cause mortality during a median follow-up period of 20±11 months. CPO at rest was calculated as: [Cardiac output * mean arterial pressure] * K (conversion factor 2.22 × 10-3) = W. Receiver operator characteristic (ROC) analysis was used to determine discriminative capacity of CPO at rest. Kaplan-Meier estimate was used for survival analysis. A multivariable Cox proportional-hazards regression analysis was performed to identify independent risk factors for all-cause mortality.

230 patients (median age 77 years (interquartile range (IQR) 71-81years, 60.9% male) at high operative risk (LogEuro-SCORE 18%, IQR 12-29%) were enrolled. Median CPO at rest was 0.69 W (IQR 0.55-0.85W). At long-term follow-up, 86 patients died (37.4%). ROC curve analysis demonstrated that CPO at rest was associated with an area under the curve of 0.62 (95% confidence interval (CI) 0.55-0.70; p=0.01). A CPO at rest threshold of 0.51 W was associated with 54% sensitivity and 88.9% specificity for all-cause mortality. All-cause mortality was significantly higher in patients with CPO 0.51 W compared to those with CPO at rest >0.51 W (54.3% vs. 34.4%; log-rank p=0.02). In Cox regression analysis CPO at rest was an independent predictor for all-cause mortality (hazard ratio 0.13; 95% CI 0.04 to 0.46; p=0.002).

Conclusions: CPO at rest is associated with all-cause mortality among patients with chronic HF undergoing TEER for severe MR. Therefore, CPO at rest might be useful in risk stratification of TEER candidates.