The impact of renal insufficiency on patients outcomes in emergent angioplasty for acute myocardial infarction

BACKGROUND: Renal insufficiency (RF) was shown to be associated with a worsened prognosis following acute myocardial infarction (AMI). OBJECTIVES: The authors analyzed the outcomes of AMI patients with impaired renal function tests treated using primary percutaneous coronary intervention (PCI), to determine factors associated with increased mortality risk. METHODS: This study included 558 consecutive AMI patients treated using primary PCI between January 2001 and June 2005. The authors compared outcome results according to glomerular filtration rate (GFR). An abbreviated equation was used to calculate GFR. Patients were grouped as follow: normal (> or =90 mL/min/1.73 m(2)), mildly impaired (60-89 mL/min/1.73 m(2)), moderately impaired (30-59 mL/min/1.73 m(2)), and severely impaired GFR (< 30 mL/min/1.73 m(2)). RESULTS: There was a stepwise increase in 30-day mortality among patients with normal, mildly, moderately, and severely impaired RF: 2.1%, 3.7%, 8.2%, and 22.2%, respectively (P = 0.004). Seventeen out of the 324 with any degree of RF died within 1 month [5.3%] of these nine patients [53%] died because of cardiac cause. Univariate correlation analysis, factors associated with an increased risk of 1 month mortality included: age > 75 years, left ventricular ejection fraction < 35%, lower GFR, killip class > 1, multivessel coronary artery disease, failure to achieve TIMI flow grade = 3, the occurrence of no-reflow, IABP use, lack of administration of anti GP 2b/3a. The amount of contrast media used during the procedure [mL/Kg] as well as renal function deterioration were also associated with increased mortality. CONCLUSIONS: Clinical and angiographic parameters collected before and during PCI can be used to predict 30-day mortality among AMI patients with RF. Findings indicate that in the setting of contemporary catheter-based reperfusion strategy for AMI, the extent of coronary artery disease, measures of PCI complexity, and degree of renal impairment prior/following the procedure are altogether related to mortality.