Frequency and Predictors of Stroke After Acute Myocardial Infarction

Abstract

Background and Purpose— Stroke is a serious complication after acute myocardial infarction (AMI) and is closely associated with decreased survival. This study aimed to investigate the frequency, characteristics, and factors associated with in-hospital and postdischarge stroke in patients with AMI. Methods— Eight thousand four hundred eighty-five consecutive patients admitted to a cardiology intensive care unit for AMI, between January 2001 and July 2010. Stroke/transient ischemic attack were collected during 1-year follow-up. Results— One hundred twenty-three in-hospital strokes were recorded: 65 (52.8%) occurred on the first day after admission for AMI, and 108 (87%) within the first 5 days. One hundred six patients (86.2%-incidence rate 1.25%) experienced in-hospital ischemic stroke, and 14 patients (11.4%-incidence rate 0.16%) were diagnosed with an in-hospital hemorrhagic stroke. In-hospital ischemic stroke subtypes according to the Trial of Org 10 172 in Acute Stroke Treatment (TOAST) classification showed that only 2 types of stroke were identified more frequently. As expected, the leading subtype of in-hospital ischemic stroke was cardioembolic stroke (n=64, 60%), the second was stroke of undetermined pathogenesis (n=38, 36%). After multivariable backward regression analysis, female sex, previous transient ischemic attack (TIA)/stroke, new-onset atrial fibrillation, left ventricular ejection fraction (odds ratio per point of left ventricular ejection fraction), and C-reactive protein were independently associated with in-hospital ischemic stroke. When antiplatelet and anticoagulation therapy within the first 48 hours was introduced into the multivariable model, we found that implementing these treatments (≥1) was an independent protective factor of in-hospital stroke. In-hospital hemorrhagic stroke was dramatically increased (5-fold) when thrombolysis was prescribed as the reperfusion treatment. However, the different parenteral anticoagulants were not predictors of risk in univariable analysis. Finally, only 45 postdischarge strokes were recorded. Postdischarge stroke subtypes showed a more heterogeneous distribution of mechanisms. The annual rate of stroke post-AMI remained stable throughout the 10-year study period. Conclusions— The present study describes specific predictors of in-hospital and postdischarge stroke in patients with AMI. It showed a marked increase in the risk of death, both during hospitalization and in the year after AMI. After hospital discharge, stroke remains a rare event and is mostly associated with high cardiovascular risk.