Risk and predictors of readmission for heart failure following a myocardial infarction between 2004 and 2013: A Swedish nationwide observational study.

Background: Data are scarce regarding the risk, temporal trends and predictors of late-onset heart failure (LOHF) after acute myocardial infarction (AMI). We aimed at studying the risk and predictors of LOHF and the composite event of LOHF or death after AMI.

Methods: AMI patients first entered in the nationwide SWEDEHEART registry between 2004 and 2013 were included. Patients with a prior history of heart failure (HF) and those who died in-hospital were excluded. Dates and ICD-codes for LOHF in the national patient and death registries were used to determine time to first readmission due to LOHF and/or death.

Results: A total of 150,566 AMI patients were included in the analysis. The 1-year, 2-year and 5-year cumulative risk of developing LOHF were 11.4%, 14.6% and 21.8% respectively. The risk of LOHF within 2years decreased from 15.5% to 14.4% (2004-2005 vs 2010-2011), p<0.001. Calendar year was protective of LOHF/death after adjustment (HR 0.96, 95% CI 0.94-0.98, p<0.001). In-hospital HF, age, diabetes mellitus, chronic kidney disease, peripheral arterial disease, chronic obstructive pulmonary disease and atrial fibrillation, were strong predictors of LOHF. Risk profile improved and use of evidence based therapies increased during the time period.

Conclusions: Survivors of AMI remain at a continued risk of LOHF. However, the overall risk of LOHF shows a decreasing trend after an index AMI over time. Lower risk of LOHF may relate to decreasing burden of comorbidities and increasing use of evidence based treatments.