Contrast-induced nephropathy and acute renal failure following emergent cardiac catheterization:: Incidence, risk factors and prognosis

Introduction and objectives. The aim was to investigate the incidence and prognosis of, and predictive factors for, acute renal failure following emergent cardiac catheterization. Methods. The study involved 602 consecutive patients who underwent emergent cardiac catheterization. Acute renal failure (ARF) was defined as an increase in serum creatinine level >= 0.5 mg/dL within 72 hours following the procedure. Predictive factors for and the prognosis of ARF were evaluated in an initial cohort of 315 patients, and a risk score was derived. The risk score was validated in a second cohort of 287 patients. The median (interquartile) follow-up time was 1.3 years (0.8-2.0 years). Results. Seventy-two of the 602 patients (12.0%) developed ARF. In the initial cohort of 315 patients, the following factors were predictors of ARF: cardiogenic shock at admission (odds ratio [OR] 4.56), diabetes mellitus (OR 2.98), time to reperfusion > 6 hours (OR 3.18), anterior myocardial infarction (OR 2.61), baseline serum creatinine level >= 1.5 mg/dL (OR 3.51), and baseline serum urea level >= 50 mg/dL (OR 3.00). A risk score based on these variables was constructed in which cardiogenic shock = 3 points and each of the remaining variables = 2 points. Patients in the validation cohort were divided into five risk categories: in those with 0 points, the incidence of ARF was 1.2%; with 2-3 points, 8.7%; with 4-5 points, 12.5%; with 6-7 points, 46.2%; and with >= 8 points, 66.7% (P <.0001). Cox regression analysis showed that ARF was a powerful predictor of total mortality (hazard ratio [HR] 5.97, 95% confidence interval [Cl] 2.54-14.03; P <.0001) and of a major cardiovascular event (HR 3.29, 95% Cl 1.61-6.75; P=.001). Conclusions. The incidence of ARF after emergent cardiac catheterization is high. Cardiogenic shock, diabetes mellitus, myocardial infarction location, time to reperfusion, and serum creatinine and urea levels are predictors of ARF Patients who developed this complication had higher mortality and major cardiovascular events rates.