Mitral ratio of peak early to late diastolic filling velocity as a predictor of mortality in middle-aged and elderly adults: the Strong Heart Study.

Abstract

With aging, left ventricular filling tends to decrease in early diastole, reducing the mitral ratio of peak early to late diastolic filling velocity (E/A). However, the prognostic significance of low or high E/A in older adults remains to be elucidated in population-based samples. Doppler echocardiograms were analyzed in 3008 American Indian participants in the second Strong Heart Study examination who had no more than mild mitral or aortic regurgitation. Participants were followed for a mean of 3 years after Doppler echocardiography to assess risks of all-cause and cardiac death associated with E/A <0.6 or >1.5; 2429 (81%) participants had normal E/A ratio, 490 (16%) had E/A <0.6, and 89 (3%) had E/A >1.5. All-cause mortality was higher with E/A <0.6 or E/A >1.5 (12% and 13% versus 6%), as was cardiac mortality (4.5% and 6.5% versus 1.6%; both P<0.001). Adjusting for age, sex, body mass index, systolic blood pressure, HDL and LDL cholesterol, smoking, hypertension, diabetes, coronary heart disease, left ventricular hypertrophy, and low ejection fraction (<40%), the relative risk of all-cause death with E/A >1.5 was 1.73 (95% CI, 0.99 to 3.03; P=0.05); the relative risk of cardiac death was 2.8 (95% CI, 1.19 to 6.75; P<0.05). E/A <0.6 was not independently associated with increased all-cause or cardiac mortality (P=0.19 and 0.31, respectively) after adjusting for covariates. In a population-based sample of middle-aged and elderly adults, mitral E/A >1.5 at baseline Doppler echocardiography is associated with 2-fold increased all-cause and 3-fold increased cardiac mortality independent of covariates; mitral E/A <0.6 was also associated with 2-fold increased all-cause and cardiac mortality but not independent of covariates.