Related Experiment Video
Updated: Feb 27, 2026
The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Improved Algorithm for Ostium Size Assessment in Watchman Left Atrial Appendage Occlusion Using Three-Dimensional
Maximilian Schmidt-Salzmann1, Felix Meincke, Felix Kreidel
1Cardiologicum Hamburg, Schloßgarten 3, 22041 Hamburg, Germany. docbergmann@me.com.
Aims:
Correct sizing of the ostium is a crucial step in left atrial appendage (LAA) occlusion procedures. However, unfavorable anatomy of the ostium often complicates the assessment of the true ostium diameter. We hypothesized that area-derived diameter (ADD) and perimeter-derived diameter (PDD) from three-dimensional transesophageal echocardiogram (3D-TEE) can facilitate this step of the procedure as compared with two-dimensional (2D) measurements.
Methods And Results:
For 55 patients within the ALSTER-LAA registry, retrospective analysis of PDD and ADD was correlated with 2D measurements used during the procedure to ascertain correct size of the Watchman device (Boston Scientific). The observed data were put into relation to the calculated area of the device with 10%-30% compression and the clinical outcome after 30 days. 3D area and perimeter measurements of the LAA ostium matched the calculated range of the different device sizes. Recapture during implantation, gaps <5 mm, and device size changes were more often observed when ADDs would also have suggested the use of a larger device.
Conclusion:
3D ADDs and PDDs are feasible to use in device size decisions. Employing these measurements may allow operators to further reduce intraprocedural recapture maneuvers, peridevice leakage, and device size changes.
