A novel echocardiographic parameter for predicting the ischemic etiology of cardiomyopathy and its prognosis in patients with congestive heart failure.

BACKGROUND

Although previous studies have established the ability of mitral annular velocities and velocity dispersion indices to differentiate between ischemic cardiomyopathy (ICM) and nonischemic cardiomyopathy, prospective data are lacking on both the use of heterogeneity of mitral annular velocities to predict the ischemic etiology in patients with left ventricular dysfunction and further cardiovascular prognosis.

METHODS

A total of 232 patients with left ventricular ejection fractions < 40% were admitted between 2008 and 2010. Doppler tissue imaging was performed on six mitral annular sites for three consecutive beats and then averaged for each site. Systolic (Vs') and early (Ve') and late (Va') diastolic mitral annular velocity dispersion indices among the six mitral annular sites were calculated.

RESULTS

Ve' was a significant predictor (P < .01) of ICM in multivariate logistic regression models adjusted for clinical variables and conventional echocardiography. The optimal cutoff value for predicting ICM was Ve' ≥ 16.7 with an area under the receiver operating characteristic curve of 0.92. Its sensitivity and specificity were 87% and 85%, respectively. During follow-up (median, 32 months), 64 participants experienced cardiac mortality. The adjusted hazard ratio in Cox proportional-hazards analysis for death in the third tertile in comparison with the first tertile of Ve' was 2.92 (P = .02).

CONCLUSIONS

A high degree of heterogeneity of e', expressed as Ve', provides incremental value over clinical variables and conventional echocardiography to predict the prevalence of low left ventricular ejection fractions patients with ICM. Furthermore, elevated Ve' could also identify patients at a high risk for cardiac mortality.