Does longitudinal global strain by speckle tracking predict major adverse cardiac events better than LVEF in symptomatic heart failure patients?
Longitudinal global strain by speckle tracking is an independent predictor of major adverse cardiac events in heart failure patients, offering superior prognostic value compared to LVEF.
BACKGROUND: Longitudinal myocardial deformation indexes appear superior to left ventricular ejection fraction (LVEF) in assessing myocardial contractility. However, few studies have addressed the prognostic value of longitudinal motion markers (velocity, strain, and strain rate) in predicting outcome in heart failure patients. METHODS AND RESULTS: The study included 125 consecutive symptomatic heart failure patients (63+/-16 years, 77% male, LVEF=31+/-10%). All patients underwent a complete echocardiographic and clinical examination, and brain natriuretic peptide level was assessed in 93 patients. Longitudinal myocardial velocity by tissue Doppler imaging, global-epsilon, and strain rate by speckle tracking were computed from apical views (4-, 3-, and 2-chambers views) and compared with the occurrence of major adverse cardiac events. On the whole, peak longitudinal velocity, global-epsilon, and strain rate averaged 5+/-2 cm/s (range, 1 to 9), -8+/-3% (range, -3 to -18), and -0.33+/-0.16 s(-1) (range, -0.83 to -0.05), respectively. During the follow-up period (266+/-177 days), major adverse cardiac events occurred in 47 (38%) patients (15 deaths, 29 recurrent heart failure, and 4 heart transplantations). By univariable analysis using Cox model global-epsilon, strain rate, and LVEF were associated with the occurrence of major adverse cardiac events, whereas only global-epsilon remained independently predictive of outcome by multivariate analysis. CONCLUSIONS: In the heart failure population, longitudinal global strain by speckle tracking is superior to LVEF and other longitudinal markers in identifying patients with poor outcome.
Nahum et al. (Wed,) studied this question.