Assessment of left atrial appendage function by transesophageal echocardiography. Implications for the development of thrombus.
- 1 July 1991
- journal article
- abstracts
- Published by Ovid Technologies (Wolters Kluwer Health) in Circulation
- Vol. 84 (1), 223-231
- https://doi.org/10.1161/01.cir.84.1.223
Abstract
BACKGROUND The predilection of the left atrial appendage (LAA) for thrombus formation has long been known. METHODS AND RESULTS We prospectively studied the two-dimensional echocardiographic and Doppler patterns of LAA function in 82 patients by transesophageal echocardiography. In the 63 patients in sinus rhythm, LAA area was measured during LAA diastole at the onset of the electrocardiographic (ECG) P wave (LAAmax) and after LAA systole at the ECG R wave (LAAmin) and LAA ejection fraction was calculated as (LAAmax-LAAmin)/LAAmax; peak Doppler velocity was recorded from the LAA outlet. The 58 patients in sinus rhythm without LAA thrombus were grouped according to left atrial size on transthoracic echocardiography; 39 patients had a left atrial size of less than 40 mm (group 1) and 19 had a left atrial size of 40 mm or greater (group 2). Five patients in sinus rhythm had LAA thrombus. In the 19 patients with atrial fibrillation or flutter LAAmax was measured independent of the ECG; three of these patients had LAA spontaneous contrast, four had thrombus, and one had both. Patients in sinus rhythm without LAA thrombus demonstrated a characteristic pattern of a contractile LAA apex and a noncontractile base with color flow and pulsed Doppler evidence of LAA emptying that coincided with the P wave. Patients in sinus rhythm with LAA thrombus had a mean +/- SD LAAmax (8.0 +/- 1.5 cm2) larger than that in group 1 (5.0 +/- 1.9 cm2) (p less than 0.01) but not group 2 (6.7 +/- 3.1 cm2), LAAmin (6.5 +/- 1.0 cm2) larger than that in both group 1 (2.3 +/- 1.5 cm2) and group 2 (4.2 +/- 2.7 cm2) (p less than 0.01), and LAA ejection fraction (17 +/- 11%) and LAA velocity (0.24 +/- 0.10 m/sec) less than those in both group 1 (55 +/- 21% and 0.48 +/- 0.24 m/sec, respectively) and group 2 (45 +/- 27% and 0.46 +/- 0.24 m/sec, respectively) (p less than 0.01). Patients with atrial fibrillation or flutter with LAA spontaneous contrast and/or thrombus had LAAmax (10.4 +/- 6.6 cm2) greater than that in patients with atrial fibrillation or flutter without LAA contrast and/or thrombus (6.8 +/- 3.0 cm2) (p less than 0.05). The LAA appeared as a static pouch in seven of eight of the former compared with in two of 11 of the latter. When attempted, Doppler demonstrated a recognizable fibrillatory LAA outflow velocity pattern in none of three in the former versus four of seven in the latter group. CONCLUSIONS We conclude that the LAA has a characteristic pattern of emptying in sinus rhythm. LAA thrombus formation in sinus rhythm and atrial fibrillation is associated with both poor LAA contraction and LAA dilation.Keywords
This publication has 10 references indexed in Scilit:
- Risk Factors for Thromboembolic Complications in Chronic Atrial FibrillationArchives of Internal Medicine, 1990
- Preliminary Report of the Stroke Prevention in Atrial Fibrillation StudyNew England Journal of Medicine, 1990
- Incomplete Left Atrial Appendage Ligation that Simulates Mitral RegurgitationJournal of the American Society of Echocardiography, 1990
- Transesophageal Echocardiography: Technique, Anatomic Correlations, Implementation, and Clinical ApplicationsMayo Clinic Proceedings, 1988
- Left atrial spontaneous echo contrast in mitral valve disease: An indicator for an increased thromboembolic riskJournal of the American College of Cardiology, 1988
- Transesophageal two-dimensional echocardiography for the detection of left atrial appendage thrombusJournal of the American College of Cardiology, 1986
- Two-dimensional echocardiographic imaging of left atrial appendage thrombiJournal of the American College of Cardiology, 1984
- Detection of left atrial thrombi by echocardiography.Heart, 1981
- Extreme hypertrophy of the left atrial appendage: The case of the giant dog ear∗The American Journal of Cardiology, 1960