Fig. 1

Transesophageal echocardiography measurements for left atrial appendage closure using the Watchman device and the the Amplatzer Cardiac Plug/Ultraseal devices. For the Watchman device (a/b), the LZ (orange line) measurement is taken from the circumflex artery medially to 1-2 cm laterally inside the limbus, and the depth (red line) is measured from the LZ to the most distal tip of the main lobe. For the Amplatzer or the Ultraseal devices (c/d), the orifice (yellow line) is the line that connects the circumflex artery to the pulmonary vein ridge, and the LZ (orange line) is measured at 10-12 mm within the LAA orifice .The depth (red line) is measured from the orifice to the back wall of the LAA in a perpendicular line. LAA: left atrial appendage; LZ: landing zone