Objectives: The incidence of contrast-induced nephropathy (CIN) after coronary angiography and the prognostic value in patients with acute myocardial infarction remains to be determined. This study investigated the frequency, predictors of CIN, and the prognostic significance of CIN in acute myocardial infarction patients undergoing emergent coronary angiography.
Methods: This study included 132 consecutive acute myocardial infarction patients undergoing emergent coronary angiography within 24 hr after the onset between January 1999 and June 2001. The serum creatinine concentration was measured on admission and at 48 hr after contrast medium exposure. CIN was defined as an increase in serum creatinine from the baseline > or = 0.5 mg/dl or > or = 25% at 48 hr after emergent coronary angiography. The patient characteristics, and in-hospital and long-term mortality were compared between the CIN and non-CIN groups.
Results: CIN occurred in 15 patients (11.4%) after emergent coronary angiography. The predictor of CIN development was preexisting renal impairment (serum creatinine concentration > or = 1.2 mg/dl on presentation; 21.9% vs 8.0%, odds ratio 3.22, 95% confidence interval 1.07-9.74, p = 0.04). In-hospital mortality was significantly higher in the CIN group than in the non-CIN group (13.3% vs 1.7%; odds ratio 8.85, 95% confidence interval 1.15-68.2, p = 0.01). The long-term mortality (mean follow-up period of 40 months) was also higher in the CIN group (26.7% vs 8.6%; hazard ratio 3.91, 95% confidence interval 1.21-12.5, p = 0.02).
Conclusions: CIN was an independent predictor of both in-hospital and long-term mortality in acute myocardial infarction patients undergoing emergent coronary angiography. Preexisting renal insufficiency was associated with subsequent CIN.