Persistent Renal Dysfunction in Patients Undergoing Primary Percutaneous Coronary Intervention for Acute Myocardial Infarction

Abstract

Background: The long-term prognosis of patients with acute myocardial infarction who develop persistent renal dysfunction (RD) remains unclear. We investigated risk factors and prognostic implications of persistent RD after contrast-induced nephropathy (CIN) in patients with acute myocardial infarction after primary percutaneous coronary intervention. Methods and Results: We enrolled 952 consecutive patients who underwent primary percutaneous coronary intervention for acute myocardial infarction. CIN was defined as an increase in serum creatinine levels ≥0.5 mg/dL or ≥25% from baseline within 72 hours after percutaneous coronary intervention. Persistent RD was defined as residual impairment of renal function over 2 weeks, and transient RD was defined as recovery of renal function within 2 weeks, after CIN. The overall incidence of CIN was 8.8% and that of persistent CIN was 3.1%. A receiver-operator characteristic curve showed that the optimal cutoff value of the contrast volume/baseline estimated glomerular filtration rate ratio for persistent CIN was 3.45. In multivariable logistic analysis, a contrast volume/baseline estimated glomerular filtration rate >3.45 was an independent correlate of persistent RD. At 3 years, the incidence of death was significantly higher in patients with persistent RD than in those with transient RD (P=0.001) and in those without CIN (P<0.001). Cox regression analysis showed that persistent RD (hazard ratio, 4.99; 95% CI, 2.30–10.8; P<0.001) was a significant risk factor for mortality. A similar trend was observed for the combined end points, which included mortality, hemodialysis, stroke, and acute myocardial infarction. Conclusions: Persistent RD, but not transient RD, is independently associated with long-term mortality. A contrast volume/baseline estimated glomerular filtration rate >3.45 is an independent predictor of persistent RD.