Cardiac lymphatic dysfunction and repair in cardiovascular disease.

The field of cardiac lymphatic research has expanded considerably over the past decade. Clinical studies have uncovered lymphatic remodelling in a wide range of cardiovascular diseases, and experimental research has demonstrated that these structural alterations often lead to dysfunction of lymphatic transport. Given the vital physiological role of lymphatics, insufficient lymphatic drainage can affect several aspects of cardiac pathophysiology, including myocardial fluid balance, the immune microenvironment, collagen turnover and lipid handling. In this Review, current knowledge on cardiac lymphatics is summarized, including the structural and molecular specializations underlying their diverse homeostatic functions, and how these features can be altered in cardiovascular diseases. The latest research on the effects of inflammation on lymphatics is presented, together with the mechanisms by which lymphatics modulate immunity. The regulation of cardiac lymphangiogenesis is discussed, including accumulating evidence of immune cell-lymphatic crosstalk in the heart, the role of metabolic and biomechanical stimulation of lymphangiogenesis, and examples of experimental approaches to therapeutic lymphangiogenesis and their current limitations. Finally, areas for future research are highlighted, including the translation of lymphatic imaging and lymphangiogenic therapies to the clinic for patients with cardiovascular disease.