No cardioprotective benefit of ischemic postconditioning in patients with ST-segment elevation myocardial infarction

Abstract

Background Postconditioning is a potential cardioprotective strategy that has demonstrated conflicting and variable reductions in infarct size in human trials. Objectives To determine whether postconditioning could increase the extent of myocardial salvage in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention (PPCI). Methods One hundred two patients (aged 57 ± 11 years; 88% male) were randomly assigned to a postconditioning or standard protocol. Cardiovascular magnetic resonance imaging was performed 3 days after PPCI to measure the volumetric extent of myocardial necrosis and the area at risk. Results With similar time-to-reperfusion (170 ± 84 minutes in the postconditioning group vs. 150 ± 70 minutes in the standard group, P = 0.22), the myocardial salvage index was not significantly different between the postconditioned group and the control group, averaging 42 ± 22% vs. 33 ± 21%, respectively (P = 0.08). Furthermore, postconditioning was not associated with a smaller infarct size compared to controls (13 ± 7 g/m2 vs. 15 ± 8 g/m2, respectively, P = 0.18). Conclusions Postconditioning does not significantly increase myocardial salvage or reduce infarct size in patients with STEMI undergoing PPCI. However, the possibility of a more modest impact of postconditioning cannot be excluded with our sample size. © 2013, Wiley Periodicals, Inc.