Venous trunk FMA:30314 Tubular organ part, the wall and lumen of which are continuous with those of the atria of the heart, directly or indirectly through tributaries of the venae cavae, pulmonary veins and the hepatic and portal veins. Examples: coronary sinus, posterior intercostal vein, hepatic vein, bronchial vein, pulmonary vein, trunk of inferior vena cava. fma Segment of venous tree organ