Left Atrial Appendage (LAA) Occluders After Catheter Ablation of Atrial Fibrillation

The procedure is performed under transesophageal echocardiographic (TEE) guidance. After a transseptal puncture is performed, a pigtail catheter is maneuvered into the LAA to perform an LAA angiogram. Through the use of a combination of this angiographic and TEE information, a Watchman device, ranging in size between 21 and 33 mm in diameter, is selected. The device comes prepackaged in a catheter-based delivery system that is advanced into the LAA through a 12F transseptal sheath (outer diameter, 14F). Proper positioning and stability of the device are verified by TEE and angiography before device release.

The left atrium (LA) and pulmonary veins (PVs) were explored through a transseptal approach. Real-time three-dimensional (3D) LA maps were reconstructed by using a nonfluoroscopic navigation system (CARTO, Biosense-Webster Inc.). The ipsilateral left and right PVs were encircled in 1 lesion line by circumferential PV isolation. Radiofrequency energy was delivered at 43◦C, 35 W, 0.5 cm away from the PV ostia at the anterior wall, and was reduced to 43◦C, 30 W, 1 cm away from the PV ostia at the posterior wall, with a saline irrigation speed of 17 mL/min. Each lesion was ablated continuously until the local potential amplitude decreased by \>80% or RF energy deliveries exceeded 40 seconds. The endpoint of circumferential PV isolation was PV isolation; this was confirmed when Lasso mapping showed the disappearance of all PV potentials or the dissociation of PV potentials from left atrial activity.