Intradevice misalignment predicts residual leak in patients undergoing left atrial appendage closure

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.