Right atrial spontaneous echo contrast and thrombi in atrial fibrillation:A transesophageal echocardiography study

Background: Previous studies have reported the clinical and echocardiograph ic findings of patients with left atrial spontaneous echo contrast (SEC) an d thrombi. We sought to study these characteristics in patients with right atrial SEC and thrombi; Methods: We reviewed 580 consecutive patients from the ACUTE (Assessment of Cardioversion Using Transesophageal Echocardiography) Registry and found 7 9 patients (14%, aged 67 +/- 13 years, 67 male) with transesophageal echoca rdiography (TEE) findings of right atrial SEC or thrombi (group 1). This gr oup was compared with a control group of 75 consecutive patients (group 2) (aged 68 +/- 13 years, P = not significant; 49 male, P < .005) from the reg istry with no TEE findings of SEC or thrombi in the left or right atrium. Results: Atrial fibrillation was present in 60 of 79 group I patients (76%) . Five right atrial (6%) and 11 left atrial (14%) thrombi were identified. Both left ventricular election fraction (39% +/- 16% versus 47% +/- 14%; P = .0005) and presence of right ventricular dysfunction (n = 44 versus 18; P = .0001) differed significantly between groups 1 and 2, respectively. Righ t atrial area (24 +/- 6 cm(2) versus 22 +/- 6 cm(2); P = .02) was larger in patients in group 1. Left atrial SEC was present in 68 of 73 group 1 patie nts (86%). Patients with right atrial thrombi and right atrial SEC had a lo nger duration of arrhythmia (524 +/- 812 days versus 147 +/- 368 days, P < .05) than patients with right atrial SEC only. Conclusions: Right atrial SEC has a prevalence of 14% in patients with atri al arrhythmia who undergo TEE-guided cardioversion. Right atrial thrombi ar e a rare finding and were seen in fewer than 1% (5/580) of patients with at rial arrhythmia Right atrial thrombi among patients on anticoagulation ther apy were not associated with clinically significant pulmonary embolism.