Remote ischemic preconditioning reduces cardiac troponin I release in cardiac surgery: a meta-analysis

Objectives: To determine whether remote ischemic preconditioning (RIPC) reduces myocardial injury, mortality, morbidity, and resource utilization in cardiac surgery.

Design: Meta-analysis of controlled clinical trials. The primary outcome was cardiac troponin I (cTnI) concentrations. Secondary outcomes included cardiac troponin T (cTnT) concentrations, myocardial infarction, stroke, renal failure requiring hemodialysis, atrial fibrillation, inotropic score, mechanical ventilation time, length of intensive care unit stay, length of hospital stay, and death.

Setting: University hospitals.

Patients: Adult and pediatric patients undergoing cardiac surgery, including coronary artery bypass grafting, valve procedures, and correction of congenital cardiac anomalies.

Interventions: Remote ischemic preconditioning through limb ischemia.

Measurements and main results: Nineteen randomized trials involving 1,235 patients were included in the meta-analysis. The cTnI concentrations at 6 (or 4-8) hours postoperatively and the total cTnI released after surgery showed a statistically significant reduction in the RIPC group compared with a control group (weighted mean difference [WMD] -2.03 ug/L, 95% confidence interval [CI] -3.25 to -0.82 ug/L, p = 0.001; WMD -65.74 ug/L*h, 95% CI -107.88 to -23.61 ug/L*h, p = 0.002, respectively). There were no differences in mortality, morbidity, and resource utilization between groups.

Conclusions: Current evidence suggests that RIPC reduces cardiac troponin I release in patients undergoing cardiac surgery. The clinical significance of these observations merits further investigation.