[Silent ischemia after an uncomplicated myocardial infarct. A study in asymptomatic patients]

To verify the prognostic value of silent myocardial ischemia (SMI) after an uncomplicated myocardial infarction (MI).

Forty asymptomatic patients were studied after a first uncomplicated MI. They were submitted to 48 hour ambulatory electrocardiographic monitoring and exercise-testing, during the 2nd and 8th weeks after the acute event. Thirty-nine patients were submitted to cardiac catheterization and coronary arteriography; one patient was submitted to necropsy. The electrocardiographic study identified 11 (27.5%) individuals with SMI (group A); the other 29 patients were considered group B.

Groups A and B were similar in relation to clinical characteristics, infarct site and ventricular function. Group A had significantly more extensive coronary artery disease when compared to group B. After a two-year follow-up, patients from group A had significantly more coronary events (36.3%) when compared to group B (3.4%). Kaplan-Meier analysis demonstrated a significantly higher cumulative probability of not experiencing a new coronary event for the group B patients.

SMI may have a prognostic value after uncomplicated MI, as in other clinical manifestations of coronary artery disease.