Prognostic implications of moderate secondary mitral regurgitation after optimized medical therapy in heart failure
C Ferrero Molina, P Codina, J Lupon, M Ruiz-Cueto, E Zamora, A Borrellas, C Llibre, C Badia-Molins, A Carrete, E Santiago-Vacas, M Domingo, J Butler, G W Stone, V Delgado, A Bayes-GenisAbstract
Background
Secondary mitral regurgitation (SMR) frequently develops due to left ventricular remodeling in patients with heart failure with reduced ejection fraction (HFrEF). While severe SMR worsens outcomes in HF, the prognostic significance of moderate SMR after optimization of guideline-directed medical therapy (GDMT) remains uncertain.
Methods
We analyzed 2,468 ambulatory HF patients who underwent paired transthoracic echocardiography at baseline and after 12 months of optimized GDMT. Mean baseline LVEF was 36.1% ± 13.6%. SMR severity at 12 months was classified as none/mild, moderate, or severe. The primary endpoint was the composite of all-cause death or first heart failure hospitalization (HFH). Secondary endpoints included all-cause mortality and recurrent HFHs. Median follow-up after the 12-month echocardiogram was 6.9 years.
Results
At 12 months of optimized GDMT, 80.5% of patients had no/mild SMR, 15.6% had moderate SMR, and 3.9% had severe SMR. Compared with no/mild SMR, both moderate and severe SMR at 12 months were independently associated with a higher risk of the primary composite endpoint (moderate: hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.47–1.95; severe: HR 1.81, 95% CI 1.44–2.29). Moderate SMR was also associated with increased all-cause mortality (HR 1.54, 95% CI 1.32–1.79) and recurrent HFHs (incidence rate ratio [IRR] 2.17, 95% CI 1.81–2.60). Among patients with moderate SMR at 12 months, outcomes did not differ according to baseline SMR severity.
Conclusions
In this large-scale study, in a predominantly HFrEF population receiving contemporary GDMT, residual moderate SMR at 12 months was common and was independently associated with mortality and HFH, with a prognostic impact comparable to severe SMR.Risk of the Primary Composite EndpointRecurrent heart failure hospitalizations