Tissue Doppler E/E' ratio is a powerful predictor of primary cardiac events in a hypertensive population: an ASCOT substudy

Abstract

Patients with controlled hypertension are at risk of future cardiac events, but predicting first events remains difficult. We hypothesized that modern echocardiographic measures of left ventricular diastolic function may be more sensitive than traditional echocardiographic methods of risk prediction and set out to test this in a cohort of patients with well-controlled hypertension. Conventional and tissue Doppler echocardiography was performed on 980 participants in the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT). All subjects had hypertension, but no known cardiac disease. Cardiac events were defined as fatal and non-fatal myocardial infarction (including silent myocardial infarction), coronary revascularization procedures, new-onset angina (stable or unstable), fatal and non-fatal heart failure, and life-threatening arrhythmias. Analysis was performed by a single, blinded observer. There were 56 primary cardiac events during 4.2 ± 0.7 years follow-up. The ratio of transmitral Doppler early filling velocity to tissue Doppler early diastolic mitral annular velocity (E/E′) was the strongest predictor of first cardiac events in Cox-proportional hazards models. Following adjustment for covariates, a unit rise in the E/E′ ratio was associated with a 17% increment in risk of a cardiac event (HR 1.17, CI 1.05–1.29; P = 0.003). Tissue Doppler E/E′, a non-invasive estimate of left atrial filling pressure, independently predicts primary cardiac events in a hypertensive population and out-performed traditional echocardiographic measures in this moderately sized, well-treated hypertensive population. E/E′ represents a simple, effective tool for assessing cardiac risk in a hypertensive population.