Predictors and outcome of contrast-induced acute kidney injury in older patients presenting with acute coronary syndrome

Abstract Background The number of older patients presenting with acute coronary syndrome (ACS) is increasing. Routine percutaneous coronary intervention (PCI) is performed in order to improve outcome, but comorbidities associated with aging lead to a higher risk of treatment complications. Contrast-induced acute kidney injury (CI-AKI) represents potential harm in older and frail patients, but its impact on long term prognosis is not clear. Purpose To evaluate occurrence, predictors, and impact on long term outcome of CI-AKI in elderly patients presenting with ACS. Methods A prospective cohort of 392 older (≥70 years) ACS patients who underwent coronary angiography was enrolled. CI-AKI was defined as a serum creatinine increase at least ≥0.3 mg/dl in 48 h or at least ≥50% in 7 days. According to our department protocol, prophylactic hydration was performed to all patients with isotonic saline, given intravenously at a rate of 1 ml/kg body weight/h (0.5 ml/kg for patients with left ventricular ejection fraction