Veins of the heart. Lymphatic system of the heart.
The veins of the heart do not open into the hollow veins, but directly into the cavity of the heart.
Intramuscular veins are located in all layers of the myocardium and, accompanying the arteries, correspond to the course of the muscle bundles. Small arteries (up to the 3rd order) are accompanied by double veins, large – single. Venous outflow follows three paths:
1) into the coronary sinus, 2) into the anterior veins of the heart, and 3) into the smallest veins that flow directly into the right side of the heart. In the right half of the heart of these veins more than in the left, in connection with which the coronary veins are more developed on the left.
The predominance of the smallest veins in the walls of the right ventricle with a small outflow through the venous sinus system indicates that they play an important role in the redistribution of venous blood in the region of the heart.
1. Veins of the coronary sinus system, sinus coronarius cordis. It is the remnant of the left common cardinal vein and lies in the posterior part of the coronary furrow of the heart, between the left atrium and the left ventricle. With its right, thicker end, it flows into the right atrium near the septum between the ventricles, between the valve of the inferior vena cava and the atrium septum. The following veins flow into sinus coronarius: a) v. cordis magna, starting at the apex of the heart, rises along the anterior interventricular sulcus of the heart, turns to the left and, rounding the left side of the heart, continues into sinus coronarius; b) v. posterior ventriculi sinistri – one or more venous trunks on the posterior surface of the left ventricle, flowing into the sinus coronarius or v. cordis magna; c) v. obliqua atrii sinistri – a small branch located on the posterior surface of the left atrium (remnant embryonic v. cava superior sinistra); it begins in the pericardial fold, enclosing the connective tissue strand, plica venae cavae sinistrae, also representing the remainder of the left vena cava; d) v. cordis media lies in the posterior interventricular sulcus of the heart and, reaching the transverse sulcus, flows into the sinus coronarius; e) v. cordis parva is a thin branch located in the right half of the transverse sulcus of the heart and usually flowing into the v. cordis media in the place where this vein reaches the transverse sulcus.
2. Anterior veins of the heart, vv. cordis anteriores, are small veins that are located on the anterior surface of the right ventricle and flow directly into the cavity of the right atrium.
3. The smallest veins of the heart, vv. cordis minimae, – very small venous trunks, do not appear on the surface of the heart, but, having gathered from capillaries, flow directly into the atrial cavities and to a lesser extent the ventricles.
In the heart, there are 3 networks of lymphatic capillaries: under the endocardium, inside the myocardium and under the epicardium. Among the receptacles, two main lymphatic collectors of the heart are formed. The right collector occurs at the beginning of the posterior interventricular sulcus; it takes the lymph from the right ventricle and the atrium and reaches the left upper anterior nodes of the mediastinum lying on the aortic arch near the beginning of the left common carotid artery.
The left collector is formed in the coronary sulcus at the left edge of the pulmonary trunk, where it receives vessels that carry the lymph from the left atrium, the left ventricle and partly from the anterior surface of the right ventricle; then it goes to the tracheobronchial or tracheal nodes or to the nodes of the root of the left lung.