RESUMEN
BACKGROUND: Heart failure (Killip>I) in patients with acute coronary syndrome (ACS) is a recognized risk factor for death. However, its relationship with the risk of new acute ischemic events has not been well established. OBJECTIVE: The aim of this study has been to evaluate the association between Killip>I on admission and the risk of a new acute myocardial infarction (AMI) during follow-up due to ACS. PATIENTS AND METHODS: A total of 972 and 426 survivors of an ACS with non-ST segment evaluation (Non-STE-ACS) and AMI with ST segment elevation (STEMI) were studied prospectively and consecutively. The presence of Killip>I was determined on admission together with the classical prognostic variables. The relationship between Killip>I and subsequent post-discharge AMI was established with the Cox regression adapted for competitive events. RESULTS: During a median follow-up of 3 years, 135 (13.9%) and 53 (12.4%) patients with Non-STE-ACS and STEMI presented a new AMI. Patients with Non-STE-ACS and STEMI with Killip>I (15.6% and 21.3% respectively) showed a higher incidence of AMI (28.3 vs 6.3 and 10.6 vs 3.3 per 100 patients-years of follow-up, p<0.001, respectively). In the multivariate analysis, adjusted for traditional risk factors and controlled for competitive events (death and revascularization), confirmed that Killip>I subjects with Non-STE-ACS and STEMI showed a significantly higher risk of AMI (HR: 1.76; CI 95%: 1.15-2.68; p=0.009 and HR: 1.90; 95% CI: 1.07-3.36; p=0.029 respectively). CONCLUSIONS: In patients with Non-STE-ACS and STEMI, the presence of Killip>I on admission is independently associated to an increased risk of long-term AMI.