Renoprotective effect of remote ischemic post-conditioning by intermittent balloon inflations in patients undergoing percutaneous coronary intervention.

OBJECTIVES The aim of the present study was to assess the efficacy of remote ischemic post-conditioning (RIPC) by repeated intermittent balloon inflations in preventing acute kidney injury (AKI) in patients with a non-ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention (PCI). BACKGROUND AKI complicating PCI is associated with increased morbidity and mortality. Remote ischemic preconditioning, using cycles of upper limb ischemia-reperfusion as a conditioning stimulus, has been recently shown to prevent AKI in patients undergoing elective coronary angiography. METHODS Eligible patients were randomized to receive RIPC by cycles of inflation and deflation of the stent balloon during PCI or a sham procedure (control patients). The primary endpoint was AKI, defined as an increase of ≥ 0.5 mg/dl or ≥ 25% in serum creatinine within 96 h from PCI. The 30-day rate of death or re-hospitalization for any cause was one of the secondary endpoints. RESULTS A total of 225 patients were included (median age, 68 years; 36% female). The AKI rate in the RIPC group was 12.4% versus 29.5% in the control group (p = 0.002; odds ratio: 0.34; 95% confidence interval: 0.16 to 0.71). The number needed to treat to avoid 1 case of AKI was 6 (95% confidence interval: 3.6 to 15.2). The 30-day rate of death or re-hospitalization for any cause was 22.3% in the control group versus 12.4% in RIPC patients (p = 0.05). CONCLUSIONS RIPC by serial balloon inflations and deflations during PCI was found to confer protection against AKI in patients with a non-ST-segment elevation myocardial infarction undergoing PCI. The reduction in the rate of AKI translated into a clear trend (of borderline significance) toward better 30-day clinical outcome.