Cardiac Dysfunction Assessed by Echocardiographic Tissue Doppler Imaging Is an Independent Predictor of Mortality in the General Population

Abstract

Background— Tissue Doppler imaging (TDI) detects left ventricular dysfunction in patients with heart failure and normal ejection fraction, but the prognostic significance of left ventricular dysfunction by TDI in the general population is unknown. Methods and Results— Within the Copenhagen City Heart Study, a large community-based population study, cardiac function was evaluated in 1036 participants by both conventional echocardiography and TDI. Averages of peak systolic (s′), early diastolic (e′), and late diastolic (a′) velocities from 6 mitral annular sites were used. TDI was furthermore quantified by a combined index (eas index) of diastolic and systolic performance: e′/(a′×s′). During follow-up (median, 5.3 years), 90 participants died. Left ventricular dysfunction by TDI, in terms of low s′ (hazard ratio, 1.23 per 1-cm/s decrease; P <0.05) and a′ (hazard ratio, 1.20 per 1-cm/s decrease; P =0.001), were significant predictors of death in Cox proportional-hazards models adjusted for clinical variables (age, sex, body mass index, heart rate, hypertension, diabetes mellitus, and ischemic heart disease) and conventional echocardiography. The adjusted hazard ratio for death in the third tertile compared with the first tertile of the combined index of systolic and diastolic performance by TDI was 2.5 ( P <0.005). Conclusions— In the general population, in which most are free of left ventricular systolic dysfunction and restrictive diastolic filling using conventional echocardiographic parameters, left ventricular dysfunction by TDI is a powerful and independent predictor of death, especially when systolic performance and diastolic performance are considered together, recognizing their interdependency and their complex relation to deteriorating cardiac function.