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.
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.
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.
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).
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.