Contrast-Induced Nephropathy After Cardiac Catheterization: Culprits, Consequences and Predictors

Contrast-induced nephropathy (CIN) is a common complication after radiocontrast exposure.

A retrospective medical record review of 513 hospitalized patients who underwent cardiac catheterization from June-December 2014 was done, of which 38 patients with end-stage renal disease and 57 patients without preprocedural creatinine were excluded. Serum creatinine concentration before the procedure and each day for 3 days after the procedure was recorded. CIN was defined as an increase in serum creatinine concentration by ≥25% or ≥0.5mg/dL from the preprocedural value within 72hours of contrast exposure.

A total of 418 patients (mean age: 69.1 ± 13.8 years, 55% males) were included in the study. Mean incidence of CIN was 3.7% (n = 16). CIN accounted for longer duration of hospitalization, lengthier intensive care unit admission, requirement of hemodialysis and higher mortality. Incidence of CIN was higher in the presence of preexisting atrial fibrillation (AF), congestive heart failure (CHF) and chronic kidney disease (CKD). When tested by univariate analysis, incidence of CIN was 13.8% in the AF group (P < 0.001), 8.6% in CHF group (P < 0.01) and 8.9% in CKD group (P < 0.002), compared with 2.3%, 1.9% and 2.4% in the absence of preexisting AF, CHF and CKD, respectively. On further testing using multivariate logistic regression model using AF, CHF and CKD as independent variables, development of CIN was strongly associated with preexisting AF with an odds ratio of 4.11, 95% CI: 1.40-12.07, P = 0.01.

Identifying patients at risk is an important step in preventing CIN. Preexisting AF, independent of traditional risk factors, may increase the risk for CIN.