Incidence of left atrial thrombi in patients in sinus rhythm and with a recent neurologic deficit.

OBJECTIVES: We sought to determine the incidence of left atrial (LA) thrombi in patients in sinus rhythm (SR) and with a recent neurologic deficit and to analyze the relation between LA thrombi and LA chamber and appendage function in patients in SR. METHODS: A prospective study was conducted in 869 consecutive patients. The study group consisted of 583 patients in SR (67%). The remaining 286 patients had atrial fibrillation (AF) and served as controls (33%). RESULTS: The incidence of LA thrombi was significantly higher in patients with AF (n = 39 [14%]) compared with patients in SR (n = 6 [1%]; P <.001). Three of 6 patients with thrombi in SR had mitral stenosis, 1 patient had aortic stenosis, 1 patient had coronary artery disease, and another patient had a cardiomyopathy. Of the patients with detected thrombi, those in SR did not receive anticoagulation, whereas those with AF did in 18 cases. Patients with thrombi in SR and with AF did not significantly differ in LA diameter (5.1 +/- 0.8 cm vs 4.8 +/- 0.7 cm; 95% confidence interval [CI], -0.78 to 0.45), left ventricular ejection fraction (46% +/- 13% vs 42% +/- 15%; 95% CI, -18.7 to 7.4), LA appendage area (5.8 +/- 2.7 cm(2) vs 6.7 +/- 3.2 cm(2); 95% CI, -1.9 to 3.6), peak emptying velocity of the LA appendage (0.19 +/- 0.08 m/s vs 0.17 +/- 0.07 m/s; 95% CI, -0.08 to 0.04), or LA spontaneous echo contrast (3. 5 +/- 0.6 vs 3.9 +/- 0.5; 95% CI, -0.06 to 0.45). CONCLUSIONS: LA appendage thrombi are an infrequent cause of thromboembolism in patients in SR and are associated either with mitral valve disease or LA chamber and appendage dysfunction. Routine transesophageal echocardiography for the exclusion of LA thrombi is not recommended in patients in SR without underlying heart disease and normal LA function as assessed by transthoracic echocardiography.

Right atrial appendage thrombosis in atrial fibrillation: its frequency and its clinical predictors.

This study assesses the incidence of right atrial (RA) chamber and appendage thrombosis in patients with atrial fibrillation (AF) in relation to RA appendage morphology and function. Transthoracic and multiplane transesophageal echocardiography were performed in 102 patients with AF to assess the incidence of RA and left atrial (LA) thrombi and spontaneous echo contrast. Both right and left ventricular sizes, atrial chamber and appendage sizes and function were measured. Twenty-two patients in sinus rhythm served as the control group (SR). Complete visualization of the RA appendage was feasible in 90 patients with AF. Patients with AF had lower tricuspid annular excursion (p = 0.008) and larger RA chamber area (p = 0.0001) than patients in SR. In addition, RA appendage areas were larger (p <0.05) and RA ejection fraction and peak emptying velocities (both p <0.0001) were lower in patients with AF patients than in those in SR. Equivalent differences were found for the LA appendage. Six thrombi were found in the RA appendage and 11 thrombi in the LA appendage in AF patients. Spontaneous echo contrast was found in 57% and 66% in the right atrium and in the left atrium, respectively. AF patients with RA appendage thrombi had a larger RA area (p = 0.0001), and lower RA appendage ejection fraction and emptying velocities (both p = 0.0001) than patients without thrombi. Spontaneous echo contrast was detected in all patients with thrombi. Spontaneous echo contrast was the only independent predictor of RA (p = 0.03) and LA appendage thrombosis (p = 0.036). In conclusion, multiplane transesophageal echocardiography allows the assessment of RA appendage morphology and function. RA spontaneous echo contrast is the only independent predictor of RA appendage thrombosis.

Left atrial appendage function in patients with atrial flutter.

OBJECTIVE: To determine whether echocardiographic markers thromboembolic risk differ between patients with pure atrial flutter and patients with atrial flutter and intermittent atrial fibrillation. DESIGN: Patients with atrial flutter were followed up prospectively for 12 months to identify intermittent atrial fibrillation. After the follow up period, transthoracic and multiplane transoesophageal echocardiography were performed to assess left atrial chamber and appendage size, peak emptying velocities, and emptying fraction of the left atrial appendage. The presence of spontaneous echo contrast was also determined. SETTING: Tertiary cardiac care centre. PATIENTS: 20 consecutive patients with atrial flutter; 11 healthy subjects in sinus rhythm served as controls. RESULTS: Intermittent atrial fibrillation was documented in 11 patients by Holter monitoring or surface ECG; atrial fibrillation was not found in the other nine patients. Compared with the patients with pure atrial flutter, patients with atrial flutter and intermittent atrial fibrillation had larger left atrial chamber (mean (SD) 4.5 (0.6) v 3.8 (0.5) cm; 95% confidence interval 0.2 to 1.2; P = 0.01) and appendage areas (6.7 (2.2) v 4.8 (4.9) cm; 95% CI 0.4 to 3.5; P = 0.02), lower left atrial appendage emptying fractions (33 (11)% v 52 (11)%; 95% CI 8 to 29; P = 0.008), and also lower left atrial appendage emptying velocities (0.44 (0.21) v 0.79 (0.27) m/s; 95% CI 0.13 to 0.56; P = 0.005). In addition, a higher incidence of spontaneous echo contrast (11% v 36%) was observed in patients with atrial flutter and intermittent atrial fibrillation. CONCLUSIONS: Left atrial appendage function is depressed and spontaneous echo contrast more frequent in patients with atrial flutter and intermittent atrial fibrillation, as opposed to patients with pure atrial flutter. These data support the concept that patients with atrial flutter and intermittent atrial fibrillation have an increased risk of thromboembolic events and should therefore receive adequate anticoagulant treatment.