Purpose: To assess factors of importance for long term prognosis in patients with acute myocardial infarction (AMI) and heart failure and normal or mildly reduced left ventricular systolic function.
Subjects and methods: Seventy-one consecutive AMI-survivors with clinical or radiological signs of heart failure and an echocardiographically determined wall motion score >1.2 (EF >35-40%) were followed during 11 years for mortality, heart failure readmissions and new ischemic events.
Results: Seventeen patients died (24%) while the combined endpoint of death or a new ischemic event (MI or hospitalisation for angina pectoris) occurred in 40 (56%) and fatal or non-fatal heart failure in 20 (28%) patients, respectively. A pre-discharge echocardiographic assessment of diastolic function was obtained in 67 patients out of whom 56 (84%) had diastolic dysfunction, most frequently relaxation abnormalities (43%). Wall motion score did not differ between survivors and non-survivors (1.48+/-0.20 vs. 1.44+/-0.18; p=0.46). Adjusting for age, sex and wall motion score N-terminal pro-ANP, prolongation of the isovolumic relaxation time and exercise induced ST-depressions at discharge (global chi2=26.2; p<0.0001) remained as independent mortality predictors while re-admission for heart failure was predicted by wall motion score, N-terminal pro-ANP and previous heart failure (global chi2=23.7; p<0.001). Death or new ischemic events were associated with low Doppler A-wave flow velocity and male sex (global chi2=14.0; p<0.01).
Conclusions: Evaluation of diastolic function and a natriuretic peptide adds prognostically important information in AMI-patients with clinical heart failure and normal or mildly reduced left ventricular systolic function. Isovolumic relaxation time is an independent predictor of long term mortality and N-terminal pro-ANP of mortality and heart failure.