Under general anesthesia, intubation with double-lumen endotracheal tube for selective lung ventilation, and transesophageal echocardiography (TEE) to confirm the presence of thrombi in the left atrial appendage (LAA) are carried out. Defibrillator pads are placed before surgery.

The patient is positioned supine. In order to widely expose the anterior axillary line, the left arm is slightly flexed and a small inflatable pillow is placed beneath the left scapula.

Port-access points are then marked: for the camera and CO2 insufflation port in the 3^rd intercostal space on the anterior axillary line, and for the instrumentation ports in the 2^nd and the 5^th intercostal spaces, slightly anteriorly to delineate a triangle with the base parallel to the sternum and the apex at the level of the camera port. Conversely, in the left thorax the instrumentation ports are marked approximately in the mid-axillary line, and the 6^th intercostal space is chosen instead of the 5^th in longitypes.