Background: TIA has been recently re-defined as "a transient episode of neurological dysfunction caused by ischemia without acute infarction." The gold standard to exclude the presence of ischemic lesions is acute brain MR. However, in many clinical settings, the 24/7 availability of MR is, at best, irregular. Being so, an appropriate adoption of this definition, which excludes the presence of ischemic lesions, can only be equally irregular. Our aim was to retrospectively compare the long-term outcomes of patients receiving acute care for TIA diagnosed with the new, tissue-based definition, and those diagnosed only on symptom duration.
Methods: We analyzed 480 patients (227 males) from two centers: group 1 consisted of 162 patients with time-defined TIA; group 2 of 315 patients with negative brain DW-MRI (tissue-based TIAs). We considered the combined recurrence of TIA, stroke, myocardial infarction, and angina as endpoints.
Results: Both groups had a similar mean follow-up duration (38.3 months vs. 37.2 months) and were comparable for vascular risk factors, clinical features, and etiology. The combined endpoint rates were 11.1% for both groups, and the rates for segregate endpoints did not differ between groups. Recurrence was correlated with atrial fibrillation, diabetes, and high diastolic blood pressure.
Conclusions: The long-term outcomes of TIA patients did not differ according to the definitions applied. Therein suggesting that, even without acute MRI results, a clinical diagnosis seemed to be enough to assure prompt medical treatment and similar long-term outcomes.
Keywords: Diffusion-weighted magnetic resonance; Transient ischemic attack.