Long-term Follow-up of Patients Undergoing Postconditioning During ST-Elevation Myocardial Infarction

Abstract

Reperfusion injury may offset the optimal salvage of myocardium achieved during primary coronary angioplasty. Thus, coronary reperfusion must be combined with cardioprotective adjunctive therapies in order to optimize myocardial salvage and minimize infarct size. Forty-three patients with their first ST-elevation myocardial infarction were randomized to myocardial postconditioning or standard of care at the time of primary coronary angioplasty. Postconditioning was performed immediately upon crossing the lesion with the guide wire and consisted of four cycles of 30 s occlusion followed by 30 s of reperfusion. End-points included infarct size, myocardial perfusion grade (MPG), left-ventricular ejection fraction (LVEF), and long-term clinical events (death and heart failure). Despite similar ischemic times (≅4.5 h) (p = 0.9) a reduction in infarct size was observed among patients treated with the postconditioning protocol. Peak creatine phosphokinase (CPK), as well as its myocardial band (MB) fraction, was significantly lower in the postconditioning group when compared with the control group (CPK--control, 2,444 ± 1,928 IU/L vs. PC, 2,182 ± 1,717 IU/L; CPK-MB--control, 242 ± 40 IU/L vs. PC, 195 ± 33 IU/L; p = 0.64 and p < 0.01, respectively). EF in the postconditioning group was improved when compared with the control group (control, 43% ± 15 vs. PC, 52% ± 9; p = 0.05). After a mean follow-up of 3.4 years, a 6-point absolute difference in LVEF was still evident in the postconditioning group (p = 0.18). MPG was better among patients treated with the postconditioning protocol compared with control (2.5 ± 0.5 vs. 2.1 ± 0.6; p = 0.02). Due to the small sample size no significant differences in clinical events were detected (p value for death = 0.9; p value for heart failure = 0.2). A simple postconditioning protocol applied at the onset of mechanical reperfusion, resulted in reduction of infarct size, better epicardial and myocardial flow, and improvement in left ventricular function. The beneficial effects of postconditioning on cardiac function persist beyond 3 years.

Time to Give Up on Cardioprotection?

“…[73][74][75][76][77][78][79][81][82][83]86,[91][92][93] In most of the studies, the patient cohorts were small; of note, the 3 studies with the largest patient cohorts were neutral with respect to infarct size. 90,94,96 All studies in adult 97,98 or pediatric [99][100][101][102][103] cardiac surgery reported a significant infarct size reduction, as reflected by biomarker (creatine kinase-muscle brain, and troponin) release.…”

Pharmacological and physical prevention and treatment of no-reflow after primary percutaneous coronary intervention in ST-segment elevation myocardial infarction

“…Remote preconditioning is unique in that it can be applied during myocardial ischaemia, prior to reperfusion. 42 Garcia et al 46 demonstrated that a simple postconditioning protocol (performed immediately on crossing the lesion with the angioplasty guidewire, and consisting of four cycles of 30 s of occlusion followed by 30 s of reperfusion), applied at the onset of mechanical reperfusion, resulted in a reduction in infarct size, better epicardial and myocardial flow and improved left ventricular function. In addition, the beneficial effects of postconditioning on cardiac function were shown to persist >3 years.…”

“…In addition, the beneficial effects of postconditioning on cardiac function were shown to persist >3 years. 46 …”

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

“…[58] опубликовали резуль-таты наблюдений за больными ОИМ с подъемом сег-мента ST (n =43). Среднее время от момента возникнове-ния коронарной катастрофы до реперфузии было равно 4,5 ч. Посткондиционирование осуществляли с помощью 4 циклов реперфузии (30 с) и ишемии (30 с).…”