Method for coronary artery bypass

The invention comprises a method for performing a coronary artery bypass graft on a beating heart under thoracoscopic visualization without opening the chest wall. At least one small opening is formed in the patient's chest, a target artery for an arterial blood supply is located, instruments are introduced through one or more small openings formed in the patient's chest to prepare the target artery for fluid connection to the coronary artery, and instruments are introduced through one or more small openings formed in the patient's chest to connect the target artery to the coronary artery distal from a stenosis. In a preferred embodiment, a minimal left anterior intercostal thoracotomy provides access to form an anastomosis between the left internal mammary artery (LIMA) and the left anterior descending artery (LAD) while thoracoscopic viewing facilitates harvesting the LIMA. In other embodiments, access to the patient's heart may be obtained through a trocar sheath or other means for providing percutaneous access to the patient's thoracic cavity without opening the chest wall. Thoracoscopic visualization, depending on the procedure, is used to locate the arterial blood supply, the location of the coronary artery to be bypassed and the location of the occlusion in the artery. In other embodiments, the diagonal (Dx) or circumflex (Cx) arteries may be bypassed.