Prognostic significance of eGFR in patients with acute coronary syndromes and preserved renal function.

Introduction: The influence of moderate and severe renal disease on the outcome in patients with acute coronary syndromes (ACS) is well established. However, the association with mild renal disease is less well defined. Aim of the study: The aim of the present study was to assess the prognostic significance of estimated glomerular filtration rate (eGFR) in patients with ACS treated with primary PCI and preserved renal function on a 2-year follow-up. We also investigated whether eGFR value within limits of normal influences the success of primary PCI. Material and methods: We retrospectively studied 770 patients with ACS (ST-segment elevation myocardial infarction [STEMI], non-ST-segment elevation myocardial infarction [NSTEMI], unstable angina [UA]) consecutively referred to the catheterization laboratory of our hospital for emergency primary PCI in the year 2005. The cutoff value of eGFR was 60 ml/min/1.73 m2. The patients were subsequently divided into 2 groups according to their renal function, as assessed by eGFR: 1st group with eGFR 60-90 ml/min/1.73 m2 and 2nd with eGFR>90 ml/min/1.73 m2. The primary end-point was all-cause mortality on a 2-year follow-up. Results: A total of 770 patients (187 women, 24%; mean age 62±11 years) were included in the analysis. The mean eGFR was 86±18 ml/min/1.73 m2. Renal function with eGFR>90 ml/min/1.73 m2 was present in 262 patients (34%) and eGFR value 60-90 ml/min/1.73 m2 was found in 508 patients (66%). Lower eGFR values were associated with older age (p<0.0001), female gender (p<0.0001), hypertension (p=0.0008), impaired glucose tolerance (IGT) or impaired fasting glucose (IFG) (p=0.02) and lower LVEF (p<0.0001). There was a higher rate of unstable angina (p=0.0048) among patients with eGFR 60-90 ml/min/1.73 m2. During the 2-year follow-up, 7% (n=55) of the patients died. All-cause mortality was significantly higher in patients with lower eGFR (60-90 ml/min/1.73 m2) (p=0.01), lower LVEF (p=0.00), diabetes (p=0.03), hyperlipidemia (p=0.0001) and higher heart rate on admission (p=0.007). Long-term mortality significantly correlated with unsuccessful PCI (p=0.03) and the stenosis apart from the IRA (p=0.01). The mortality rates in patients with eGFR 60-90 ml/min/1.73 m2 were significantly higher than in eGFR>90 ml/min/1.73 m2 group (9% vs 4% respectively, p=0.02). Conclusions: In patients with ACS and preserved renal function the value of eGFR correlates with all-cause mortality on a 2-year follow-up. Mild renal disease may be used in risk stratification in ACS patients treated invasively. Values of eGFR in population with preserved renal function do not influence the rate of successful coronary interventions. [ABSTRACT FROM AUTHOR]