The relationship between mitral regurgitation and ejection fraction as predictors for the prognosis of patients with heart failure.

AIMS: To study whether there is interaction between mitral regurgitation (MR) and left ventricular ejection fraction (LVEF) in the mortality risk of heart failure (HF) patients. METHODS AND
RESULTS: We studied a large group of patients hospitalized for symptoms and clinical signs of HF in the period 2001-02. Mitral regurgitation was diagnosed on echocardiography and qualitatively graded as no/trace, mild, moderate, and severe using the colour Doppler method. Median follow-up time was 4.5 years. Three thousand and seventy-eight patients with HF were included, of whom 1890 patients (61%) had no/trace MR, 628 (20%) had mild MR, 452 (15%) had moderate MR, and 108 (4%) had severe MR. During follow-up, 1660 deaths (54%) were registered. In univariate analysis, increasing severity of MR carried an increasing mortality risk, hazard ratio (HR) 1.10, 95% confidence interval (CI) 1.04-1.16, P = 0.0006 for each increasing degree of MR. In multivariable analysis, with adjustments made for age, sex, ejection fraction, serum creatinine, presence of ischaemic heart disease, chronic obstructive pulmonary disease, diabetes, and stroke, similar results were found, but only in patients with LVEF<25%, HR 1.14, 95% CI 1.03-1.26, P = 0.01 for each increasing degree of MR. This risk was driven by moderate and severe MR. For patients with LVEF≥25% the HR was 0.91, 95% CI 0.82-1.03, P = 0.2 for each increasing degree of MR.
CONCLUSION: Mitral regurgitation has a negative effect on prognosis of patients with HF, but only in patients with severely reduced LVEF.