Prognostic impact of renal dysfunction on long-term mortality in patients with preserved, moderately impaired, and severely impaired left ventricular systolic function following myocardial infarction

OBJECTIVE: The aim of this study was to investigate and compare the prognostic impact of renal dysfunction (RD) at admission in patients with preserved, moderately impaired and severely impaired left ventricular systolic function following ST-elevation myocardial infarction (STEMI). METHODS: We included 2436 patients with STEMI treated with primary percutaneous coronary intervention (pPCI). Patients presenting with cardiogenic shock and those on hemodyalisis were excluded. According to the left ventricular ejection fraction (EF), patients were divided in three groups: preserved left ventricular systolic function – EF >50%, moderately impaired – EF=40%-50% and severely impaired left ventricular systolic function-EF <40%. RD was defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73m(2) at admission. The follow-up period was 6 years. RESULTS: Preserved, moderately impaired and severely impaired systolic function were found in 741 (30.5%), 1367 (56.1%) and 328 (13.4%) patients, respectively. RD was present in 105 (14.2%) patients with preserved systolic function, 247 (18.1%) patients with moderately impaired, and 120 (36.5%) patients with severely impaired systolic function.Regardless of the presence of RD, 6-year mortality rates in patients with preserved, moderately impaired, and severely impaired systolic function were 2.7%, 5.2% and 31.1% respectively. Within each LVEF group, patients with RD had a worse outcome, both in the short- and long-term. In the Mulivariate Cox Analysis, RD remained an independent predictor of 6-year mortality in patients with moderately (HR 2.52, 95% CI 1.54-3.78) and severely impaired systolic function (HR 2.84, 95% CI 1.68-5.34), but not in patients with preserved left ventricular systolic function (HR 0.59, 95% CI 0.14-1.41). CONCLUSION: Although patients with RD had higher 6-year mortallity following STEMI regardless of LVEF, RD at admission remained a strong independent predictor for 6-year mortality only in patients with moderately and severely impaired left ventricular systolic function.