PROSPECTIVE-STUDY OF PATIENTS AGED 55 YEARS OR LESS WITH ACUTE MYOCARDIAL-INFARCTION BETWEEN 1981 AND 1985 - OUTCOME 7 YEARS AND BEYOND

Objective - To determine the long-term prognosis of patients after a m yocardial infarction (MI) at a young age. Design - Prospective cohort study of patients aged 55 years or less suffering a myocardial infarct ion. Setting - A single coronary care unit admitting patients from the community. Patients - 255 consecutive patients (210 men) aged 55 year s or less admitted between 1981 and 1985 after acute MI. Twenty four p atients died in hospital or within 3 months of infarction and 11 were lost to further follow up after discharge. Of the remaining patients, 150 (mean (SD) age 48 (5.7) years) able to exercise 3 weeks after infa rction and who agreed to undergo coronary angiography were recruited t o a study group and seen 18 months, and 3, 5, and 7 years after MI. In addition, a cross sectional analysis of survival was made to a median of 120 months. Seventy 3 month survivors (mean (SD) age 48 (5.8) year s) were not recruited to the study group but were traced for late surv ival through their general practitioners and family health service ass ociations to a median of 130 months. Main outcome measures - Survival in young patients after MI and the survival of 3 month survivors strat ified by their ability to exercise and agreement to undergo angiograph y. The rate of coronary artery surgery (CAGB) and reinfarction during the first 7 years after index MI in patients recruited to the study gr oup. Results-Sixteen patients (6%) died in hospital and eight (3%) wit hin 3 months of the index infarction. The 7 and 11 year survival rates in the whole cohort of 255 patients were 80% and 66% respectively usi ng life table methods. Survival 7 years after MI, in patients recruite d to the study group was better than in those not recruited (93% v 79% , P = 0.001), but thereafter mortality in the study group accelerated and there was no significant difference in survival 11 years after inf arction (76% v 67%, P = 0.05). There was a trend towards higher mortal ity in patients with multivessel disease and severely impaired left ve ntricular function. During the first 7 years after MI, 38 of 150 patie nts in the study group underwent CABG and 19 suffered reinfarction, wh ich was fatal in three. Conclusion - The medium-term prognosis of youn g survivors of MI is good, particularly in patients recruited to the s tudy group. After 7 years there is an increase in mortality and the lo ng-term prognosis is less favourable. This should be taken into accoun t when planning future management and follow up of young patients afte r MI.