Peripheral endothelialization progression on fluoropolymer-coated left atrial appendage closure devices: Does device position influence healing?

Figures

• 

  Figure 1. Anatomic and procedural findings highlighting the spatial relationship between the left atrial appendage closure (LAAC) device and pulmonary veins. Electroanatomic mapping image (A), 3-dimensional reconstruction of the left atrium (B), and axial computed tomography (CT) slice (C) obtained from a contrast-enhanced CT scan performed 8 years prior to the index procedure (upper panel), illustrating the anatomic configuration of the left atrium and pulmonary veins. Notably, the LSPV stump was excluded from the initial mapping owing to concerns regarding potential procedural injury. Voltage mapping of the left atrium during the repeat ablation procedure (D). The LAAC device is visualized as a yellow translucent structure delineated by a white box, whereas the contour of the LSPV stump is demarcated by a white dotted line. Ablation was carefully performed under continuous real-time guidance using intracardiac echocardiography to ensure accurate catheter navigation and prevent mechanical contact between the catheter tip and LAAC device (E and F). LAA = left atrial appendage; LIPV = left inferior pulmonary vein; LSPV = left superior pulmonary vein; MA = mitral annulus; RSPV = right…

• 

  Figure 2. Preprocedural transesophageal echocardiography and fluoroscopic imaging during the repeat ablation procedure. 3-dimensional transesophageal echocardiography confirmed complete occlusion of the left atrial appendage (LAA) without evidence of peridevice leak or device-related thrombi. En face and orthogonal multiplanar reconstruction images (green line 135°; red line 45°) demonstrated smooth continuity between the device surface and adjacent endocardium along the Coumadin ridge (highlighted by yellow dotted lines). In contrast, the portion of the device facing the mitral annulus was noted to protrude 5.3 mm beyond the LAA ostium (A). During the repeat ablation, an angioscope was advanced toward the device under fluoroscopic guidance, with care taken to avoid direct contact with the device surface (B). LAO = left anterior oblique; RAO = right anterior oblique.

• 

  Figure 3. Direct angioscopic visualization of the device at 4 months after implantation of a fluoropolymer-coated left atrial appendage closure device. Endothelialization was assessed by segmenting the device surface into 9 predefined regions. Complete endothelial coverage was observed along the Coumadin ridge, where the device maintained smooth and continuous contact with the adjacent endocardium. Peripheral progression of endothelialization was evident, with partial coverage noted around the central screw. In contrast, exposed fabric was observed in segments adjacent to the mitral annulus, where the device protruded beyond the ostium of the left atrial appendage (yellow arrowheads), indicating incomplete endothelialization.