The clinical impact of sex differences on ischemic postconditioning during primary percutaneous coronary intervention: a POST (the effects of postconditioning on myocardial reperfusion in patients with ST-segment elevation myocardial infarction) substudy.

The POST (the effects of postconditioning on myocardial reperfusion in patients with ST-Segment elevation myocardial infarction) study showed that ischemic postconditioning did not improve myocardial reperfusion in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). However, it has not been determined whether postconditioning is effective in women. This study sought to evaluate the impact of sex differences on ischemic postconditioning during the primary PCI. We analyzed clinical outcomes at 1 year in the 537 men and 163 women with STEMI, who were randomized to the postconditioning or to the conventional PCI group. Women were older, had higher rates of hypertension, were less likely to be current smokers, and had longer symptom-to-reperfusion time. The rate of major adverse cardiac events (MACE: a composite of death, myocardial infarction, severe heart failure, stent thrombosis, or target vessel revascularization) at 1 year was higher in women compared to men (9.8% vs. 5.4%, p = 0.044). MACE was significantly higher in women compared to men in the postconditioning group (12.2% vs. 5.4%, p = 0.042), but not in the conventional PCI group (7.9% vs. 5.4%, p = 0.391). However, women was not an independent predictor after adjusting baseline risk factors, angiographic and procedural parameters (HR 2.67, 95% CI 0.68-10.5, p = 0.158). Despite women having more adverse clinical characteristics, their prognosis was similar to men in the conventional group. Although women showed a higher rate of the MACE compared to men, women were not an independent predictor in the postconditioning group.

Long-term effects of ischemic postconditioning on clinical outcomes: 1-year follow-up of the POST randomized trial.

BACKGROUND: In the Effects of Postconditioning on Myocardial Reperfusion in Patients with ST-segment Elevation Myocardial Infarction (POST) trial, ischemic postconditioning failed to improve myocardial reperfusion. However, long-term effects of ischemic postconditioning on clinical outcomes are not known in patients with ST-segment elevation myocardial infarction. METHODS: A total of 700 patients undergoing primary percutaneous coronary intervention (PCI) were randomly assigned to the postconditioning group or the conventional primary PCI group in a 1:1 ratio. Postconditioning was performed immediately after restoration of coronary flow by balloon occlusion 4 times for 1 minute. Complete follow-up data for major clinical events at 1 year were available in 695 patients (99.3%), and analyses were done by the intention to treat principle. The primary outcome was a composite of death, myocardial infarction, severe heart failure, or stent thrombosis at 1 year. RESULTS: At 1 year, a composite of death, myocardial infarction, severe heart failure, or stent thrombosis occurred in 21 patients (6.1%) in the postconditioning group and 16 patients (4.6%) in the conventional PCI group (hazard ratio [HR] 1.32, 95% CI 0.69-2.53, P = .40). The risk of death (4.9% vs 3.7%, HR 1.32, 95% CI 0.64-2.71, P = .46), heart failure (2.6% vs 2.3%, HR 1.13, 95% CI 0.44-2.94, P = .80), and stent thrombosis (2.3% vs 1.7%, HR 1.34, 95% CI 0.46-3.85, P = .59) did not differ significantly between the 2 groups. CONCLUSIONS: Ischemic postconditioning does not seem to improve the 1-year clinical outcomes in patients with ST-segment elevation myocardial infarction undergoing primary PCI.

Ischemic postconditioning during primary percutaneous coronary intervention: the effects of postconditioning on myocardial reperfusion in patients with ST-segment elevation myocardial infarction (POST) randomized trial.

BACKGROUND: Ischemic postconditioning has been reported to reduce infarct size in patients with ST-segment-elevation myocardial infarction. However, cardioprotective effects of postconditioning have not been demonstrated in a large-scale trial. METHODS AND RESULTS: We performed a multicenter, prospective, randomized, open-label, blinded end-point trial. A total of 700 patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment-elevation myocardial infarction within 12 hours after symptom onset were randomly assigned to the postconditioning group or to the conventional primary PCI group in a 1:1 ratio. Postconditioning was performed immediately after restoration of coronary flow as follows: The angioplasty balloon was positioned at the culprit lesion and inflated 4 times for 1 minute with low-pressure (<6 atm) inflations, each separated by 1 minute of deflation. The primary end point was complete ST-segment resolution (percentage resolution of ST-segment elevation >70%) measured at 30 minutes after PCI. Complete ST-segment resolution occurred in 40.5% of patients in the postconditioning group and 41.5% of patients in the conventional PCI group (absolute difference, -1.0%; 95% confidence interval, -8.4 to 6.4; P=0.79). The rate of myocardial blush grade of 0 or 1 and the rate of major adverse cardiac events (a composite of death, myocardial infarction, severe heart failure, or stent thrombosis) at 30 days did not differ significantly between the postconditioning group and the conventional PCI group (17.2% versus 22.4% [P=0.20] and 4.3% versus 3.7% [P=0.70], respectively). CONCLUSION: Ischemic postconditioning did not improve myocardial reperfusion in patients with ST-segment-elevation myocardial infarction undergoing primary PCI with current standard practice.