Prognostic importance of strain and strain rate after acute myocardial infarction

Recently, strain and strain rate have been introduced as novel parameters reflecting left ventricular (LV) function. The purpose of the current study was to assess the prognostic importance of strain and strain rate after acute myocardial infarction (AMI). A total of 659 patients after AMI were evaluated. Baseline echocardiography was performed to assess LV function with traditional parameters and strain and strain rate. During follow-up, 51 patients (8%) reached the primary endpoint (all-cause mortality) and 142 patients (22%) the secondary endpoint (a composite of revascularization, re-infarction, and hospitalization for heart failure). Strain and strain rate were both significantly related with all endpoints. After adjusting for clinical and echocardiographic parameters, strain was independent related to all endpoints and was found to be superior to LV ejection fraction (LVEF) and wall motion score index (WMSI). Patients with global strain and strain rate higher than -15.1% and -1.06 s(-1) demonstrated HRs of 4.5 (95% CI 2.1-9.7) and 4.4 (95% CI 2.0-9.5) for all-cause mortality, respectively. Strain and strain rate provide strong prognostic information in patients after AMI. These novel parameters were superior to LVEF and WMSI in the risk stratification for long-term outcome.