P46 While heart failure (HF), an emerging epidemic, complicates myocardial infarction (MI), little is known on the predictors of HF post-MI, in particular the impact of reperfusion therapy. This population-based study was undertaken to examine the association between clinical characteristics and post-MI HF between 1979 and 1994. Hospitalized incident MIs were validated using enzymes, chest pain, and Minnesota coding of the ECG. Framingham criteria were used to ascertain both in- and outpatient HF. Proportional hazard regression was used to identify predictors of CHF. In the study period, 1657 patients (pts.) (mean age 67.2 ± 13.9 years, 43% women) had an incident MI. History of diabetes, hypertension and prior HF was found in 19%, 54% and 11% of pts respectively. After 5 years, 43% of pts had experienced HF. Factors independently associated with HF were (see table). There was a 2% decline per year in occurrence of HF. Adding reperfusion therapy in the model attenuated the association between year and HF (adjusted RR for reperfusion 0.67, 95% CI 0.53, 0.84, p=0.006; adjusted for year 0.99; 95% CI 0.97, 1.01, p=0.37). Thus, while remaining frequent post-MI CHF has declined over time. Reperfusion therapy accounted for most of the effect of year. Table 1.
Heart Failure after Myocardial Infarction: Clinical Presentation and Survival
Abstract Objectives To characterize the presentation and outcome of patients with heart failure (HF) after myocardial infarction (MI) according to left ventricular ejection fraction (LVEF) and test the hypothesis that the outcome of HF did not change over time. Background Little is known about the presentation and outcome of HF post-MI and how these may have changed over time. Methods Using the Rochester Epidemiology Project, all residents of Olmsted County, Minnesota who experienced an incident MI between 1979 and 1998 were identified; MI and HF were validated using standardized criteria. Subjects were followed through their community medical record. Results Between 1979 and 1998, 1915 patients with incident MI and no prior history of HF were identified. Of these, 791(41%) experienced new onset HF as defined by Framingham criteria during 6.6±5.0 years of follow-up. Forty-seven percent were men, mean age was 73±12 years. Forty-four percent had impaired LVEF, 18% preserved LVEF and 38% had no LVEF measurement within 60 days after the HF event. Median survival after HF onset was 4 years and at 5 years after HF onset, only 45% were alive. Older age, male sex, comorbidity, hypertension and no LVEF assessment were associated with increased risk of death, however, patients with impaired LVEF had the worst outcome. Over time, survival did not improve (HR for year: 1.00; 95% CI 0.99, 1.02; P=0.919) even after adjustment for baseline characteristics. Conclusion In this geographically defined cohort of patients with MI, new onset HF after the MI was frequent. When measured, LVEF was most frequently reduced, consistent with systolic heart failure. Mortality was high and did not decline over time and death was independently associated with male sex, older age, hypertension and comorbidity. It also differed according to LVEF, which was inconsistently ascertained in this setting, potentially representing practice opportunities.