Direct evidence that sustained dysfunction of left atrial appendage contributes to the occurrence of cardiogenic brain embolism in patients with paroxysmal atrial fibrillation.

OBJECTIVE: The goal of this study was to investigate transesophageal echocardiographic (TEE) findings after the termination of atrial fibrillation to clarify the direct evidence for occurrence of acute cardiogenic brain embolism (CBE) in patients with paroxysmal atrial fibrillation (PAF). PATIENTS AND METHODS: Among 98 consecutive patients with CBE, we investigated TEE in 16 patients with PAF (Group CBE, 72 +/- 10 years) within 7 days of the onset and 2 weeks after the first study, in comparison with 15 age-matched PAF patients without CBE (Group N). The duration from reversal to normal sinus rhythm to first TEE was 6 +/- 1 days in both groups.
RESULTS: There were no significant differences in left atrial dimension and emptying flow velocity of the left atrial appendage (LAA-eV) between groups. Group CBE had significantly larger LAA area (4.3 +/- 1.3 cm2 vs. 3.1 +/- 1.0 cm2, p < 0.05), smaller LAA fractional area change (LAA-FAC) (43 +/- 25% vs. 80 +/- 22%, p < 0.001), and a higher incidence of left atrial spontaneous echo contrast (LAA-SEC) (25% vs. 7%, p < 0.05) than group N, and those abnormalities in group CBE were significantly improved at the second TEE (LAA area: to 3.2 +/- 0.9 cm2, p < 0.05; LAA-FAC: to 84 +/- 26%, p < 0.001; LAA-SEC: to 0%, p < 0.05), respectively.
CONCLUSION: LAA-FAC is a more sensitive marker for LAA dysfunction than the widely used index, LAA-eV, and a sustained deterioration of LAA-FAC may be direct evidence for thrombus formation and occurrence of acute CBE in patients with PAF.