Aortic fat pad and atrial fibrillation: cardiac lymphatics revisited

Abstract

The lymphatics of the heart have not generated any broad or sustained interest among clinicians. Few publications on cardiac lymphatics are available, the anatomy is not routinely known and the true role of cardiac lymphatics remains doubtful. One important anatomical concept needing clarification is that of the lymphatic drainage of conduction tissue. The sinoatrial node lymphatic collector and right principal lymphatic trunk are both incorporated into the aortic fat pad of the ascending aorta and are the most frequently damaged lymphatic vessels during cardiac surgery. Thus, preservation of the aortic fat pad and its lymphatic collectors should reduce the incidence of new atrial fibrillation observed in patients after cardiac surgery. This review assesses current knowledge of cardiac lymphatics and shows their possible role in triggering arrhythmias in the postoperative period.

Lymphatic Vessel Network Structure and Physiology

“…Impairment of lymph flow has been associated with coronary artery injury as well as enhanced tissue damage followed by necrosis and increased interstitial fibrosis (218, 476, 696, 988). Additionally, surgery-induced damage to fat pad lymphatics located at aortic roots was reported to lead to atrial fibrillation and heart dysfunction (631). …”

Comparative and Developmental Anatomy of Cardiac Lymphatics

“…Impairment of lymph flow has been reported to be associated with coronary artery injury in human and animal hearts [3, 4] as well as with other pathologies, such as enhanced tissue damage followed by necrosis and increased interstitial fibrosis accompanied by fibroblast activation and proliferation in human and canine hearts as well as accumulation of myxoid material consisting of hyaluronic acid and chondroitin sulphates in the canine tricuspid valve [5–7]. Surgery-induced damage to adventitial fat pad lymphatics located around the aortic roots near the sinoatrial node has been reported to lead to atrial fibrillation and heart dysfunction [8]. Apart from conduction disturbances, poor myocardial contraction has also been reported [4, 7].…”

Anatomy and roles of lymphatics in inflammatory diseases

“…45 Myocardial plexuses form a dense basket-like network of lymphatic capillaries that can rapidly adapt to changes in their functional load. [46][47][48][49][50] Myocardial lymphatics drain to larger lymphatic channels that follow arterioles to the interstitial connective tissue septa around the epicardium. The small capillaries of the subepicardial area pass radially and connect with larger bordering capillaries to form the capillaries of the subepicardial plexus.…”