IN-HOSPITAL MANAGEMENT AND OUTCOMES OF ACUTE CORONARY SYNDROMES IN RELATION TO PRIOR HISTORY OF HEART FAILURE

Abstract

Acute heart failure (HF) complicating acute coronary syndromes (ACS) portends an ominous outcome. Previous history of HF is a predictor of acute decompensated HF in ACS, but the incremental prognostic significance of previous HF has not been well studied. Accordingly, we evaluated the baseline characteristics, management patterns, and clinical outcomes in relation to prior history of HF across a broad spectrum of ACS patients. Our study population consisted of ACS patients from 53 Canadian sites in the Global Registry of Acute Coronary Events (GRACE), the subsequently expanded GRACE2, and Canadian Registry of Acute Coronary Events (CANRACE) between 1999 and 2008. Patients were stratified into two groups based on history of prior HF. Multivariable logistic regression analysis was performed to assess the impact of prior history of heart failure on in-hospital mortality, adjusting for the components of the GRACE risk model. Of the 13937 eligible patients (mean age 66±13 years, 33% female, and 28.3% with ST-elevation MI), 1498 (10.7%) patients had a history of HF. Those with prior HF tended to be older, female, with higher prevalence of diabetes and previous myocardial infarction; they also had lower systolic blood pressure, higher heart rate, worse Killip class, higher creatinine, and higher GRACE risk score on presentation (all p<0.001). Previous HF was also associated with significantly worse left ventricular systolic function (p<0.001). The table summarizes the in-hospital management and outcomes. After adjusting for components of the GRACE risk model including Killip class on presentation, prior HF remained an independent predictor of in-hospital mortality (OR 1.48, 95% CI 1.08-2.03, p=0.02). Prior HF was associated with other high risk features in ACS including HF on presentation, and other adverse outcomes in hospital. After adjusting for other prognosticators, prior HF remained an independent predictor of in-hospital mortality. However, patients with prior HF were less likely to receive evidence-based medical and invasive therapies, suggesting an opportunity for more intensive treatment to improve outcomes.