Early and Mid-Term Angiographic Assessment of Internal Thoracic Artery Grafts Anastomosed to Non-Stenotic Left Anterior Descending Coronary Arteries

Abstract

Background: Mild to moderately stenotic coronary arteries present a major problem as the progression of atherosclerosis is unpredictable. In addition, residual flow from the native coronary artery has been proposed as a mechanism that reduces blood flow in bypass grafts resulting in failure of the graft. Patients and Methods: The internal thoracic artery was anastomosed to the left anterior descending coronary artery for different reasons in three patients who underwent coronary arterial surgery, with stenosis of this coronary artery changing from none to 30 %. Patients were monitored by coronary arteriography at different intervals postoperatively (from 6 days to 25 months) to assess the patency of the internal thoracic artery graft. Results: Internal thoracic artery grafts were found to be patent in all coronary arteriographies during the follow-up period. Twenty-five months after surgery, one patient showed total occlusion of the native coronary artery which was previously normal. Conclusions: Competitive flow from the native coronary artery does not seem to influence internal thoracic artery patency when grafted to a normal or mildly stenotic left anterior descending coronary artery. This information could be of help in some patients undergoing coronary artery bypass surgery with non-critical stenosis of this coronary artery. If the non-critical lesion is located proximally and if the patient has additional risk factors for coronary artery disease progression, prophylactic grafting of the left anterior descending coronary artery to the internal thoracic artery should be considered to prevent any future cardiac event, keeping in mind that this procedure may accelerate the progression of the native coronary artery disease.

Internal thoracic artery - left anterior descending coronary artery - flow competition - mild stenosis

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