Nationwide trends in development of heart failure and mortality after first-time myocardial infarction 1997-2010: A Danish cohort study.

Aims: Pharmacological and revascularization strategies following myocardial infarction (MI) have changed substantially during the last two decades. We investigated the temporal trends in heart failure (HF) incidence and mortality during the first 90 days following first-time MI between 1997 and 2010 in Denmark.

Methods And Results: Through administrative nationwide registers we identified 89,389 patients without prior HF hospitalized with first MI. The number of patients treated with percutaneous coronary intervention (PCI) days 0-1 after index MI increased from 2.5% in 1997-98 to 38.2% in 2009-10. Treatment with clopidogrel increased from 0.02% in 1997-98 to 68.1% in 2009-10 and statins from 8.1% in 1997-98 to 78.3% in 2009-10. The incidence of HF (defined as HF diagnosis or incident use of loop diuretics) decreased from 23.6% in 1997-98 to 19.6% in 2009-10 (p<0.001). Adjusted for age, sex, and comorbidity, hazard ratio was 0.77 (95% confidence interval [CI] 0.74-0.79) for developing HF in 2009-10, compared with 1997-98. Adjusted for coronary interventions, and pharmacotherapy HR increased to 0.82 (95% confidence interval (CI) 0.79-0.85) compared with 1997-98. The 90-day mortality decreased from 19.6% in 1997-98 to 11.7% in 2009-10 (p<0.001). Adjusted for age, sex, and comorbidity HR was 0.59 (CI 0.55-0.64) in 2009-10 compared with 1997-98; upon additional adjustment for coronary interventions and pharmacotherapy the estimate was 0.75 (95% CI 0.69-0.81).

Conclusion: We found a temporal decrease in HF incidence and mortality during the first 90 days after MI in 1997-2010. This could partly be explained by changes in interventional and pharmacological treatment strategies.