Early diastolic strain rate by two-dimensional speckle tracking echocardiography is a predictor of coronary artery disease and cardiovascular events in stable angina pectoris

This study aimed to clarify the diagnostic and prognostic potential of strain rate in patients with suspected stable angina pectoris (SAP). Strain rate by 2-dimensional speckle tracking echocardiography (2DSTE) has been suggested to be able to diagnose coronary artery disease (CAD) and predict cardiovascular events in various patient groups. Prospectively enrolled patients (n = 296) with suspected SAP, no previous cardiac disease, and normal left ventricular ejection fraction were examined by 2DSTE, exercise ECG, and coronary angiography. Obstructive CAD was defined as stenosis ≥ 70% in ≥ 1 coronary artery on coronary angiography (n = 107). Major adverse cardiac events (MACE) included myocardial infarction, heart failure, atrial fibrillation, and stroke. In multivariable analysis adjusted for baseline data, conventional echocardiography, and Duke score, early diastolic strain rate (SRe) was independently associated with significant CAD with a 1.35 increased risk of having CAD per 0.1 decrease in SRe (OR = 1.35, 95% CI 1.03-1.76, P = 0.027). Peak velocity of early diastolic filling (E)/SRe was not associated with significant CAD (OR = 1.14, 95% CI 0.81-1.62, P  = 0.445). MACE occurred in 34 patients (12%) during follow-up (median 3.5 years) and both SRe (HR 1.26, 95% CI (1.07-1.49), P = 0.006) and E/SRe (HR 1.24, 95% CI (1.04-1.47), P = 0.017) were independent predictors after multivariable adjustment. In patients with suspected SAP, SRe by 2DSTE was independently associated with presence of CAD. In addition, SRe and E/SRe provided independent and incremental prognostic value for predicting future MACE.