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Updated: Feb 4, 2026

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Usable implantation depth for watchman left atrial appendage occlusion is greater with appendage angiography than
Matthew S Glassy1, Gaurav Sharma1, Gagan D Singh1
1Division of Cardiovascular Medicine, University of California Davis Medical Center, California.
Objectives:
To compare left atrial appendage (LAA) angiography to transesophageal echocardiography (TEE) for assessing usable LAA depth.
Background:
TEE is typically employed for procedural measurement of LAA ostial diameter and depth. Since angiography enhances distal LAA anatomy, we sought to compare angiography to TEE for determining usable LAA depth.
Methods:
Seventy five Watchman device cases were retrospectively evaluated. Two independent cardiologists measured intraoperative LAA ostial diameter and depth at standard 0°, 45°, 90°, and 135° TEE omniplane views and in the right anterior oblique (RAO) 30°, caudal (CAUD) 30° angiographic view.
Results:
The average age and CHA2 DS2 VASc score were 74 (±7.2) years and 4.6 (±1.3), respectively. The average ostial diameter and depth (mm) by TEE were 0°: 19.6 and 26.5; 45°: 17.5 and 26.6; 90°: 18.3 and 25.1; 135°: 19.5 and 23.3. The ostial diameter and depth (mm) by RAO 30° CAUD 30° angiography were 21.1 and 29.7. This angiographic view corresponds to a TEE view between 90° and 135°. In comparison to angiography, TEE 90° underestimated the LAA ostial diameter by 2.9 ± 3.7 mm (P < 0.001) and by 1.9 ± 4.0 mm at TEE 135° (P < 0.01); Pearson's r 0.53 angiography/TEE 90° and 0.50 angiography/TEE 135°. More importantly, TEE 90° underestimated the true usable LAA depth by 5.4 ± 5.8 mm (P < 0.001) and by 7.3 ± 6.1 mm at TEE 135° (P < 0.001); Pearson's r 0.39 angiography/TEE 90° and 0.30 angiography/TEE 135°.
Conclusions:
Compared to TEE, LAA angiography provides additional depth information and may be particularly valuable when patients have insufficient depth for Watchman by TEE measures.
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