Effect of remote ischemic conditioning on infarct size in patients with anterior ST-elevation myocardial infarction.

BACKGROUND: Previous studies indicate that remote ischemic conditioning performed before percutaneous coronary intervention (PCI) reduces infarct size in patients with ST-elevation myocardial infarction (STEMI). It remains unclear whether remote conditioning affords protection when performed in adjunct to primary PCI. We aimed to study whether remote ischemic per-postconditioning (RIperpostC) initiated after admission to the catheterization laboratory attenuates myocardial infarct size in patients with anterior STEMI.

METHODS: In this prospective multicenter trial 93 patients with anterior STEMI were randomized to RIperpostC or sham procedure as adjunct to primary PCI. RIperpostC was started on arrival in the catheterization laboratory by 5-minute cycles of inflation and deflation of a blood pressure cuff around the left thigh and continued throughout the PCI procedure. Infarct size and myocardium at risk were determined by cardiac magnetic resonance at day 4 to 7. The primary outcome was myocardial salvage index.

RESULTS: There was no significant difference in myocardial salvage index between the RIperpostC and control group (median 48.5% and interquartile range 30.9%-60.8% vs 49.2% [42.1%-58.8%]). Neither did absolute infarct size in relation to left ventricular myocardial volume differ significantly (RIperpostC 20.6% [14.1%-31.7%] vs control 17.9% [13.4%-25.0%]). The RIperpostC group had larger myocardial area at risk than the control group (43.1% (35.4%-49.7%) vs 37.0% (30.8%-44.1%) of the left ventricle, P=.03). Peak value and area under the curve for troponin T did not differ significantly between the study groups.

CONCLUSIONS: RIperpostC initiated after admission to the catheterization laboratory in patients with anterior STEMI did not confer protection against reperfusion injury.