Cerebrovascular accident complicating acute myocardial infarction: incidence, clinical significance and short- and long-term mortality rates. The SPRINT Study Group.

PURPOSE

The purpose of this study was to report the incidence, the antecedents, and the clinical significance of clinically recognized cerebrovascular accidents or transient ischemic attacks (CVA-TIA) complicating acute myocardial infarction.

PATIENTS AND METHODS

During 1981 to 1983, a secondary prevention study with nifedipine (SPRINT) was conducted in 14 hospitals in Israel among 2,276 survivors of acute myocardial infarction. During the study, demographic, historical, and medical data were collected on special forms for all patients with diagnosed acute myocardial infarction in 13 of these 14 hospitals (the SPRINT registry, n = 5,839). Mortality follow-up was completed for 99% of hospital survivors for a mean follow-up of 5.5 years (range: 4.5 to 7 years).

RESULTS

The incidence of CVA-TIA was 0.9% (54 of 5,839). The latter rate increased significantly only with age, from 0.4% among patients up to 59 years old to 1.6% among those aged greater than or equal to 70 years. Multivariate analysis identified age, congestive heart failure, and history of stroke as predictors of CVA-TIA during the acute phase of myocardial infarction. Patients with CVA-TIA exhibited a complicated hospital course, with a 15-day mortality rate of 41%. Subsequent mortality rates in survivors at 1 and 5 years were 34% and 59%, respectively. Rates at the same time points in patients without CVA-TIA were 16%, 11%, and 29% (p less than 0.01). In a multivariate analysis that included age, gender, congestive heart failure, history of previous myocardial infarction, and hypertension, CVA-TIA was independently associated with increased 15-day mortality (covariate-adjusted odds ratio [OR] = 2.62; 90% confidence interval [CI], 1.59 to 4.32), as well as subsequent 1-year (OR = 3.29; 90% CI, 1.70 to 6.36) and long-term (mean follow-up = 5.5 years) mortality (OR = 2.46; 90% CI, 1.30 to 4.69).

CONCLUSION

In this large cohort of consecutive patients with myocardial infarction, CVA-TIA was a relatively infrequent complication of acute myocardial infarction. Factors independently favoring the occurrence of CVA-TIA were old age, previous CVA, and congestive heart failure. CVA-TIA occurring during acute myocardial infarction independently increased the risk of early death threefold as well as the risk of long-term mortality in early-phase survivors. (2.5-fold).