Very early risk of a significant cardiac event after a transient ischemic attack or acute ischemic stroke

Abstract

Study objectives: Current guidelines generally recommend the admission of patients with a transient ischemic attack (TIA) and acute ischemic stroke (AIS) to the hospital for evaluation. The short-term risk (90-day) of recurrent stroke and TIA after index TIA and AIS is approximately 13%; however, there are few studies delineating the short-term risk for cardiac morbidity after these neurologic events. This study determines the very early short-term risk (<48 hours from admission) of a significant cardiac event (SCE) for patients admitted to the hospital with TIA or AIS and identifies independent predictors of cardiac complications. Methods: We included all patients admitted to a large tertiary teaching hospital with the diagnosis of TIA and AIS from January 2002 to July 2002. Patients were identified by <i>International Classification of Diseases, Ninth Revision, Clinical Modification</i> (433 to 435) discharge codes verified by a neurologist. An SCE was defined as (1) ECG changes consistent with new-onset arrhythmia or ischemia; (2) elevated troponin I level; and (3) death directly related to a cardiac event. Institutional review board approval was obtained for this study. Results: One hundred ninety-eight patients were admitted with the diagnosis of TIA (n=27) and AIS (n=171); an SCE occurred in 16% (n=32) of patients. The mean age was 70 years, and 55% were women. Comorbidities included cerebrovascular disease (35%), cardiovascular disease (23%), hypertension (70%), hyperlipidemia (41%), diabetes (26%), current smoker (27%), atrial fibrillation (20%), and a family history of heart disease (30%). Those with an SCE were more likely to have diabetes (<i>P</i>=.02), hypertension (<i>P</i>=.05), current smoking (<i>P</i>=.04), or cardiovascular disease (<i>P</i>=.002). Baseline demographics and other major vascular risk factors were the same in SCE and non-SCE groups. Stroke subtypes by Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria were large-artery atherothromboembolic 32%, cardioembolic 26%, small-vessel thrombotic 32%, and other etiology 10%. Patients with cardioembolic stroke were significantly more likely to have an SCE (<i>P</i><.05). Conclusion: Short-term cardiac morbidity is substantial after a TIA or AIS. For patients admitted to our hospital with the diagnosis of TIA or AIS, the independent risk factors of cardiovascular disease, diabetes, hypertension, smoking, and suspected cardioembolic stroke subtype predicted the short-term risk for SCE. These 5 identifiers may help to determine a subset of high-risk patients who require admission to telemetry.