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Updated: Feb 21, 2026

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Intradevice misalignment predicts residual leak in patients undergoing left atrial appendage closure
Giuseppe Patti1, Roberto Scipione, Gian P Ussia
1aCampus Bio-Medico University of Rome bUniversity of Rome Tor Vergata, Rome cPresidio Ospedaliero 'Monaldi', University of Naples Federico II, Naples, Italy.
Aims:
Postdeployment mutual orientation between the disk and the lobe in patients undergoing left atrial appendage closure with Amplatzer cardiac plug/Amulet device might impact on the risk of residual leak during follow-up. Thus, we evaluated in an exploratory, pilot study whether the degree of intradevice misalignment, measured by cardiac computed tomography (CT), discriminates the occurrence of peridevice leak in those patients.
Methods:
All patients (N = 15) undergoing percutaneous left atrial appendage closure with those specific devices between April 2013 and January 2015 were prospectively included. All patients received follow-up evaluation by cardiac CT at 6 months after the intervention to calculate the angle of misalignment within the device and to detect presence of residual peridevice leak.
Results:
The angle of misalignment between the disk and the lobe of the device significantly discriminated between patients with and without peridevice leak (area under the curve 0.96, 95% confidence interval 0.88-1.0; P = 0.003), with an angle more than 20° being associated with nine-fold higher risk of residual leak. This angle of intradevice misalignment calculated by cardiac CT was significantly correlated with that measured by two-dimensional transesophageal echocardiography or X-rays in the cath lab after the device deployment (r = 0.943 and r = 0.938, respectively).
Conclusion:
A marked intradevice misalignment after Amplatzer cardiac plug/Amulet device implantation significantly predicts the occurrence of postprocedural leak in patients with atrial fibrillation; if confirmed by larger studies, these findings may impact on practice patterns.

