Predictors of Mortality in Patients With Severe Ischemic Cardiomyopathy Undergoing Surgical Mitral Valve Intervention

Background
Ischemic mitral regurgitation is associated with substantial risk of death. Although surgical mitral valve intervention (MVi) may improve symptoms, it has not been shown to improve survival. The aim of this study was to identify predictors of mortality in patients with ischemic mitral regurgitation and MVi.
Methods and Results
We evaluated 117 consecutive patients (age, 65±10 years) with advanced ischemic cardiomyopathy who underwent cardiac magnetic resonance and subsequent MVi between January 1, 2002 and January 1, 2012. Cardiac magnetic resonance was used to assess left ventricular remodeling and myocardial scarring. The effective regurgitant orifice area was calculated from the proximal isovelocity surface area by echocardiography. There were 43 deaths (37%) during follow‐up (median, 62 months). On multivariable analysis, age ≥70 years (P=0.013), diabetes mellitus (P=0.001), dyslipidemia (P=0.012), papillary muscle scar (P=0.010), incomplete revascularization (P=0.001), and total scar %×effective regurgitant orifice area ≥0.20 cm2 (P=0.005) were each independently associated with all‐cause mortality. Although patients with effective regurgitant orifice area <0.2 cm2 at baseline demonstrated an increased hazard ratio of 3.3 for every 10% increase in scar, the hazard ratio increased to 9 for every 10% increase in scar in those with baseline effective regurgitant orifice area ≥0.20 cm2. Mortality also was significantly higher in patients with incomplete revascularization compared with those with vascularized viable myocardium (61% versus 28%; P<0.001).
Conclusions
Increased total scar burden and the presence of incomplete revascularization are powerful predictors of mortality in patients with advanced ischemic cardiomyopathy undergoing MVi. Viability assessment with cardiac magnetic resonance imaging can identify which patients with ischemic mitral regurgitation are at highest risk for mortality after surgical MVi.

© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License(https://creativecommons.org/licenses/by-nc-nd/4.0/), which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.