Cardioprotective Effects of Ischemic Postconditioning in Patients Treated With Primary Percutaneous Coronary Intervention, Evaluated by Magnetic Resonance

Abstract

Background-Postconditioning has been suggested to reduce myocardial damage during primary percutaneous coronary intervention (PPCI) in patients with ST-segment-elevation myocardial infarction. However, because clinical experience is limited, we examined the cardioprotective effects of postconditioning, using cardiac MRI in patients treated with PPCI. Methods and Results-One hundred eighteen patients with ST-segment-elevation myocardial infarction referred for PPCI were randomly assigned to have either conventional PPCI or PPCI with postconditioning. Postconditioning was performed immediately after obtained reperfusion with 4 balloon occlusions, each lasting 30 seconds, followed by 30 seconds of reperfusion. The primary end point was myocardial salvage after 3 months as judged by delayed enhancement cardiac MRI. We found a 19% relative reduction of infarct size in the postconditioning group (51Ϯ16% of total area at risk versus 63Ϯ17%, PϽ0.01), corresponding to a 31% increase in salvage ratio. The number of patients developing heart failure was significantly fewer in the postconditioning group (27% versus 46%, Pϭ0.048). No significant evidence of interaction between the impact of postconditioning and the location of the culprit lesion or size of the myocardium at risk was detected (Pϭ0.21 and Pϭ0.71). Conclusions-Mechanical

Ischemic Postconditioning During Primary Percutaneous Coronary Intervention

“…Moreover, the data on infarct size measured by cardiac magnetic resonance imaging have been inconsistent among 5 previous studies. Although 2 studies reported that ischemic postconditioning reduced infarct size or increased myocardial salvage, 8,12 infarct size did not differ significantly between the 2 treatment groups in 1 study. 9 Notably, postconditioning showed harmful effects in 2 other studies.…”

“…[5][6][7] However, the results of studies using magnetic resonance imaging to evaluate the effects of postconditioning on infarct size were inconsistent. [8][9][10][11][12] Moreover, most studies have not reflected current practice patterns such as thrombus aspiration, predilation before stenting, or use of glycoprotein IIb/IIIa inhibitors. Until now, cardioprotective effects of ischemic postconditioning have not been demonstrated in a large-scale trial.…”

Ischemic postconditioning does not improve peripheral endothelial function in ST-segment elevation myocardial infarction patients

“…10 Furthermore, there was no improvement in peripheral endothelial function as assessed by FMD and PAT. Despite enthusiasm for IPC based on animal models and early surrogates of human infarct size, recent human studies utilizing cardiovascular magnetic resonance imaging have shown modest reductions, 32,33 no impact, 10,34 or potential increase 35,36 in infarct size with IPC protocols. The variability in myocardial response to IPC is likely influenced by the IPC protocols used, the method of infarct size assessment, as well as the presence of clinical confounders.…”

Adaptive Phenomenon of Ischemic Postconditioning of the Heart. Perspectives of Clinical Use

“…[53] опубликовали данные своих наблюдений за больными ОИМ (n =118) с подъ-емом сегмента ST и ангиопластикой инфаркт-связанных коронарных артерий, которую выполняли в течение 12 ч после коронарной окклюзии. Средний интервал времени от момента коронаротромбоза до ангиопластики был равен 4 ч. Больных разделили на 2 группы: 1) группа контроля (только ангиопластика); 2) группа постконди-ционирования после ангиопластики.…”

“…Кроме того, авторы установили, что посткондиционирование не оказывает достоверного эффекта на область риска. Через 3 мес после коронарной катастрофы число пациентов с сердечной недостаточностью было достоверно больше в группе контроля, чем в группе посткондициониро-вания [53]. На наш взгляд, недостаток работы в том, что авторы не попытались проанализировать эффектив-ность посткондиционирования в зависимости от длитель-ности ишемии сердца.…”