Usefulness of intensity variation in the left atrial appendage with contrast echocardiography to predict ischemic stroke recurrence in patients with atrial fibrillation.

The left atrial appendage (LAA) is 1 of the common thromboembolic sources in patients with atrial fibrillation (AF) with stroke. The aim of this study was to examine the usefulness of LAA opacification seen on contrast echocardiography for predicting stroke recurrence in patients with AF. In 192 patients with stroke with AF who underwent transesophageal echocardiography within 7 days after the onset, intracardiac intensity variation at the orifice of the LAA just after intravenous infusion of Levovist (1,500 mg) was measured. During a mean follow-up of 450 days, the association between LAA intensity variation and recurrence of cerebrovascular events was assessed. LAA intensity variation was markedly lower in 19 patients with stroke recurrence than 173 patients without stroke recurrence (8.1 +/- 4.7 vs 12.1 +/- 5.1 dB; p <0.001). LAA thrombus-negative patients with low LAA intensity variation (< or =9.2 dB; n = 45) had higher cerebrovascular recurrent event rates than those with high LAA intensity variation (>9.2 dB; n = 109; 20.0% vs 3.7%; p <0.001) and thrombus-positive patients (15.8%). Cox multivariate hazard analysis showed that of routine echocardiographic parameters, decreased LAA intensity variation was the only independent predictor of stroke recurrence (hazard ratio 5.244, p <0.01). In conclusion, LAA intensity variation on contrast transesophageal echocardiography is a new sensitive index for LAA flow stagnation and recurrent cerebrovascular events in patients with AF with stroke.