Temporal analysis of regional strain rate during adenosine triphosphate stress before and after percutaneous coronary interventions

Abstract

Regional myocardial ischemia is thought to be characterized by diastolic dysfunction. We aimed to clarify whether temporal analysis of strain rate (SR) index derived from two-dimensional speckle-tracking echocardiography (2DTE) can assess the regional myocardial ischemia or not. Forty-two patients with significant coronary stenoses were referred for percutaneous coronary intervention (PCI). 2DTE was performed before and a day after PCI. Time from aortic valve closure to peak early diastolic longitudinal SR ∆(TAVC-E SR) was measured both at baseline and during adenosine triphosphate (ATP) infusion. TAVC-E SR was calculated as TAVC-E SR during ATP infusion subtracted by TAVC-E SR at baseline. In forty-five target ischemic regions, TAVC-E SR at baseline was significantly longer than that of control regions (166 ± 28 vs. 136 ± 32 ms, P < 0.0001). TAVC-E SR in target ischemic regions significantly prolonged during ATP stress to 221 ± 37 ms (P < 0.0001), while it did not change in control regions. Immediately after PCI, TAVC-E SR in target regions significantly decreased to 135 ± 27 ms, P < 0.0001 without prolongation during ATP stress. Receiver operating characteristic curves demonstrated that ∆TAVC-E SR could assess regional myocardial ischemia by a cutoff criterion of 14 ms with sensitivity of 93% and specificity of 95%. 2DTE-derived TAVC-E SR significantly increased during ATP stress only in ischemic myocardium. This phenomenon disappeared immediately after PCI. Temporal analysis of TAVC-E SR appeared to be useful to assess the regional myocardial ischemia.