Atrial Fibrillation in Patients with Transient Ischemic Attack in Accordance with the Tissue-Based Definition.

Background: Transient ischemic attack (TIA) management requires a cardiac evaluation with a Holter electrocardiogram (ECG), preferably a long-term (24 h) electrocardiogram (LT-ECG), to detect atrial fibrillation (AF), which places patients at higher risk of cerebrovascular events. The aim of this study was to determine the frequency of AF using ECG and LT-ECG in patients with tissue-based TIA.

Methods: During a three-year period (starting in 2011), all consecutive patients with tissue-based TIA (no evidence of infarction by brain imaging) were included and prospectively evaluated.

Results: Of 861 patients (mean age, 70 ± 13 years; 49.7% women), 854 patients (99.2%) had an ECG at admission, and 338 patients (39.3%) underwent 24-h LT-ECG monitoring during hospitalization. Patients who underwent LT-ECG monitoring were significantly younger (68 vs. 71 years; P=0.001) and experienced longer symptom duration (143 vs. 79 minutes; P=0.024) compared with those who did not. Furthermore, they had lower rates of unilateral weakness (32% vs. 39%; P=0.034) and previous strokes (18% vs. 26%; P=0.007). The LT-ECG investigation was also associated with longer hospitalization (7.9 vs. 5.7 days; P<0.001). A total of 77 patients (8.9%) exhibited AF on the ECG at admission. The LT-ECG revealed AF among seven patients (2.1%); five of these received a new treatment with oral anticoagulation based on the LT-ECG findings. Using the logistic regression, the presence of AF was associated with the following: age over 65 years (odds ratio [OR], 20.6; 95% confidence interval [CI], 2.8-152; P=0.003), hypertension (OR, 3.1; 95% CI: 1-8.9; P=0.041) and increased glucose level >6.05 mmol/L) on admission (OR, 1.9; 95% CI: 1-3.5; P=0.036).

Conclusion: Cardiac evaluation with LT-ECG appears to increase the rate of detected AF and may lead to a change in secondary prophylaxis in patients with tissue-based TIA.