While high rates of mortality are recognized, data regarding recurrent ischemic events and rehospitalization for heart failure (HF) among patients with HF and acute coronary syndrome (ACS) are limited. Researchers evaluated the association between HF status (history of HF, de novo HF, and no HF) at presentation for ACS on death, future ischemic events, and re-hospitalization for HF (HHF) at 1 year after hospital discharge using Cox proportional hazards analysis and estimated cumulative event rates using cumulative incidence function. Among 47,474 patients presenting with ACS, 11.1% presented with evidence of acute HF, 55.0% of whom had no previous history of HF. Patients with prior/chronic HF were more likely to present with acute HF than those with no previous HF. Also, compared with those without HF, patients with prior and de novo HF experienced a significantly increased risk at 1 year of all-cause mortality (adjusted HR (aHR), 2.10 [95% CI, 1.80-2.45], and aHR, 1.51 [95% CI, 1.18-1.93], respectively), CV death/myocardial infarction (MI)/stroke (aHR, 1.50; [95% CI, 1.34-1.69], and aHR, 1.40 [95% CI, 1.14-1.72], respectively), recurrent MI (aHR, 1.58 [95% CI, 1.41-1.78], and aHR, 1.40 [95% CI, 1.15-1.70], respectively), stroke (aHR, 1.93 [95% CI, 1.67-2.32], and aHR, 1.38 [95% CI, 1.09-1.75], respectively), and rehospitalization for HF (aHR, 2.38 [95% CI, 2.09-2.71], and aHR, 1.53 [95% CI, 1.24-1.88], respectively). After an ACS event, both prior and de novo HF were major predictors of death, recurrent ischemic events, and rehospitalization for HF by 1 year. “These findings highlight the need for improved strategies to prevent and manage adverse outcomes in this high-risk population,” says the research team.