Combined protocol for remote ischemic conditioning as the method of cardioprotection in patients with acute ST-segment elevation myocardial infarction

Background. There is currently no commonly accepted strategy for limiting the reperfusion injury that occurs after revascularization in patients with myocardial infarction. This study aimed to investigate the efficacy of a promising cardioprotective method.Material and Methods. Patients with acute anterior ST-segment elevation myocardial infarction (STEMI) (n = 87) were included in an open-label prospective randomized controlled trial. Control group comprised patients with STEMI who underwent only primary percutaneous coronary intervention (PPCI) (n = 44). Patients of intervention group (n = 43) underwent PPCI and remote ischemic perconditioning combined with postconditioning (RIC). The efficacy of RIC was assessed based on cardiac magnetic resonance (CMR) imaging data.Results. The medians of left ventricular (LV) infarct size were significantly higher in patients of control group: 44.8 (33.6; 55.5) versus 52.7 (35.5; 73.9) mL (p = 0.039) at day 10 after STEMI and 34.0 (25.8; 39.8) mL versus 46.0 (32.8; 55.0) mL six months after STEMI in control and intervention groups, respectively (p = 0.004). The groups of patients did not differ in the sizes of area at risk relative to the total LV myocardial volume: 40 (35; 45) and 43 (34; 49)% in control and intervention groups, respectively (p = 0.232). The groups significantly differed in the ratios of infarct size to area at risk: 70.3 (65.1; 86.6)% in control group versus 63.5 (52.7; 72.0)% in intervention group (p = 0.014) as well as in the myocardial salvage indexes: 29.7 (13.5; 34.9)% in control group versus 36.5 (28.0; 47.3)% in intervention group (p = 0.014). The study showed the tendency to greater LV myocardial salvage in intervention group versus control group at six-months follow-up (p = 0.073). The groups significantly differed in the medians of microvascular obstruction volume: 1.9 (1.4; 2.9) mL in intervention group versus 2.5 (1.8; 8.1) mL in control group (p = 0.049) as well as in the proportions of microvascular obstruction in the LV myocardium: 0.94 (0.79; 1.37)% in intervention group versus 1.50 (0.89; 3.66)% in control group (p = 0.046).Conclusion. The RIC method combined with PPCI contributed to the limitation of infarct and microvascular obstruction sizes and was associated with an increase in the myocardial salvage index in STEMI patients.