Heart Failure Complicating Acute Myocardial Infarction; Burden and Timing of Occurrence: A Nation-wide Analysis Including 86 771 Patients From the Cardiovascular Disease in Norway (CVDNOR) Project.

Background: Coronary heart disease (CHD) represents often the underlying conditions for the development of heart failure (HF). We aimed at exploring the burden and timing of HF complicating an acute myocardial infarction (AMI), using the total population of AMI patients hospitalized during 2001-2009 in Norway.

Methods And Results: A total of 86 771 patients with a first AMI during 2001-2009 and without previous HF were identified in the "Cardiovascular Disease in Norway" project and followed until HF development, death, or December 31, 2009. In 16 219 patients (18.7%), HF was present on admission or developed during hospitalization for the incident AMI. HF occurrence varied according to age (8.9%, 15.2%, and 25.6% among men and 10.2%, 16.8%, and 27.1% among women ages 25-54, 55-74, and 75-85 years). Among 63 853 patients discharged alive without HF, 8058 (12.6%) were hospitalized with or died because of HF during a median follow-up time of 3.2 years. HF incidence rates (IRs) per 1000 person-years during follow-up were 31 (95% CI, 30-32) for men and 46 (95% CI, 44-47) for women (P<0.01). IRs of HF were highest during the first 6 months of follow-up, after which they leveled off and remained stable until the end of follow-up.

Conclusions: In this nation-wide cohort study, we observed that HF remains a frequent complication of the first AMI; both during the acute phase and shortly after the discharge from the hospital.