The correlation of embolic sources with infarct pattern in patients with embolic stroke
Objective:
To exclusively identify potential embolic sources (PES) applying transesophageal echocardiography (TEE) and correlate them with topographic diffusion-weighted imaging patterns (DWI) in patients with embolic stroke.
Background:
Embolic stroke of undetermined source (ESUS) has been reported to show a relatively high stroke recurrence rate. Thus, early identification of potential embolic source (PES) is critical for acute treatment and/or secondary prevention. If acute topographic diffusion-weighted imaging patterns (DWI) would correlate with specific PES, it may prove very useful.
Design/Methods:
A total of 992 consecutive patients with embolic stroke were studied. Apart from the known embolic group (n=560), we focused on the unknown embolic group (n=366) that was defined as no arrhythmia during the first day from admission and no PES after general examination. DWI were classified based on the arterial supply. Age and sex adjusted odds ratio (OR) of each DWI for the different PESs were calculated. Middle cerebral arteries (MCA) were divided into 4 segments, i.e., M1~M4. Moreover, M2 segments were subdivided into superior and inferior branches.
Results:
366 patients consisted of 168 with paroxysmal atrial fibrillation (pAf), 82 with paradoxical embolism (PxE), 71 with aorto-embolism (AoE), leaving 39 patients undetermined. The DWIs of internal carotid artery (OR: 15.0, p=0.0027), M1 (4.2, p=0.0003), inferior M2 (3.6, p=0.04) and multiple cortical branches (MCB) (21.6, p<0.0001) were significantly associated with pAf. Striatocapsular infarction (SCI) (15.1, p<0.0001) was significantly associated with PxE and multiple small scattered infarcts (8.6, p<0.0001) with AoE.
Conclusions:
The correlations of DWI with different PESs have their distinctive characteristics. The DWI of inferior M2 as well as large infarcts and multiple cortical infarcts were associated with pAf, that of SCI with PxE and MSS with AoE. The characteristic histopathology and hydrodynamic mechanism of thrombi may determine DWI.