OBJECTIVES: Information on long-term incident heart failure (iHF) after acute coronary syndrome (ACS) is limited: it comes from old studies, which do not reflect the current reality of widespread primary angioplasty, or from the controlled setting of clinical trials, with follow-up periods that in no case exceed 5 years after the event.

METHODS: Observational, restrospective, population-based study based on analysis of CatSalut health database that included 83,357 patients admitted for ACS between 1st January 2012 and 31st December 2021, excluding those with previous diagnosis of HF and those who died before discharge. Primary outcome: HF at 10 years. For both primary and secondary outcomes, time to first event was analysed in addition to total events, number (proportions) and incidence rates.

RESULTS: Mean age (SD) was 67 (13). 29% (n=23,814) were women. 23.3% developed iHF (incidence rate of 5.2 new cases per 100 person-years). Patients iHF(+) were older (75 ± 12 vs. 65 ± 13; p<0.001) and more female (38% vs. 27%; p<0.001) than those iHF(-). The frequency of cardiovascular risk factors and previously established cardiovascular disease was also higher in iHF(+) group while their income level was lower. Main risk factors for developing HF after ACS: older age (βsc per year = 0.037; p<0.001), Killip class II-III (βsc = 0.774; p<0.001) and low/very low income level (βsc = 0.737; p<0.001). The frequency of all adverse events analysed was higher in iHF(+) group, especially all-cause mortality (cumulative incidence 48.8% vs. 13.5% and incidence rate 10.5 vs. 3.1 new cases per 100 person-years); also: recurrent coronary events, MACE-4P, atrial fibrillation/flutter, stroke and terminal events.

CONCLUSIONS: In a contemporary population setting, about 1 in 4 patients developed HF within 10 years after ACS admission. Age, Killip class II-III and low income were the strongest predictors. The frequency of adverse events was higher in iHF(+), especially all-cause mortality.