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.