Significant impairment of left atrial function in patients with cardioembolic stroke caused by paroxysmal atrial fibrillation.

OBJECTIVE Patients with cardioembolic stroke (CE) caused by paroxysmal atrial fibrillation (Paf) sometimes show normal sinus rhythm on admission, which makes it difficult to diagnose them as having CE. The present study examined the differences in echocardiographic findings between patients with CE caused by Paf (the Paf-CE group) and those with non-cardiogenic embolic ischemic stroke (the Non-CE group). METHODS We examined thirty-two patients with embolic ischemic stroke presenting with a normal sinus rhythm upon admission to our hospital; 13 patients in the Paf-CE group and 19 patients in the Non-CE group. During admission, all patients underwent transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) at a normal sinus rhythm. The left atrial dimension, left ventricular end-diastolic dimension and left ventricular ejection fraction were measured using TTE. The left atrial appendage peak flow velocity (LAAPV), spontaneous echo-contrast in the left atrium (LASEC) and thrombus in the left atrium were evaluated using TEE. RESULTS Among the clinical background characteristics, hypertension was significantly more frequent in the Non-CE group than in the Paf-CE group (p<0.01). Congestive heart failure was significantly more frequent in the Paf-CE group than in the Non-CE group (p<0.05). LAAPV was significantly lower in the Paf-CE group than in the Non-CE group (34.7 cm/s vs. 64.0 cm/s, p<0.01), and the LASEC grade was significantly higher in the Paf-CE group than in the Non-CE group (p<0.01). A thrombus in the left atrium was detected in two patients in the Paf-CE group, but no thrombi were detected in any of the patients in the Non-CE group. CONCLUSION Echocardiographic evaluation is useful, as the above data indicate that the left atrial function is apparently impaired in patients with CE caused by Paf, even in a patient with an apparently normal sinus rhythm.