How Lymph Is Drained away from the Human Papillary Muscle: Anatomical Conditions

The lymphatic and venous bed was evaluated in 42 human heart papillary muscles. The lymphatics form networks in the superficial and deep layers of the subendocardium and in the myocardium of the papillary muscles. In the apical area, the subendocardial lymphatics gradually merge with the fine myocardial, developing arcades at the origins of chordae tendineae. Thicker myocardial lymphatics leave the area passing along the connective tissue septa, often in close vicinity to the blood vessels. The injection method failed to reveal deep lymphatics in the connective tissue of chordae tendineae. Lymphovenous anastomoses were disclosed in the papillary muscle. The possible morphological pathways for lymphatic drainage of the papillary muscle are as follows: (1) the lymphatic bed subendocardial and myocardial, joining on the ventricular wall bed at the muscle base, and (2) lymphovenous anastomoses, passing along from the myocardial and subendocardial lymphatic bed into the ventricular wall veins and the sinus coronarius system, or into the thebesian veins and further directly into the heart ventricles.