THORACIC CAVITY 63 



sinus; (2) the great cardiac vein; (3) the inferior (posterior) 

 ventricular vein ; (4) the middle cardiac vein ; (5) the oblique 

 vein ; (6) the small cardiac vein ; (7) the anterior cardiac 

 veins ; and (8) the venae minimae cordis. 



The coronary sinus lies at the base of the heart, in the 

 posterior part of the coronary sulcus, between the left atrium 

 and the left ventricle. It can be displayed when the apex of 

 the heart is turned upwards and to the right. Its right 

 extremity opens into the right atrium, immediately below and 

 to the left of the orifice of the inferior vena cava. At its left 



Oblique vein 



L^^>. 



__H " ^^ Great cardiac vein 



Coronary sinus 



^^ Inferior ventricular vein 



A- HT iA^^ 



Small cardiac vein 



Middle cardiac 



vdnf ^^ ^._T^*1 Great cardiac 



vein 



FIG. 30. The Coronary System of Veins on the Surface of the 

 Heart. (Diagram. ) 



extremity it receives the great cardiac vein. The great cardiac 

 vein ascends along the anterior longitudinal sulcus (Fig. 29), 

 where it lies in relation with the interventricular branch of the 

 left coronary artery. At the upper end of the interventricular 

 sulcus it turns round the left border of the heart, with the 

 circumflex branch of the left coronary artery, and it ends in 

 the left extremity of the coronary sinus. The inferior 

 (posterior) ventricular vein or veins, from the diaphragmatic 

 surface of the left ventricle, and the middle cardiac vein, which 

 runs posteriorly in the inferior longitudinal sulcus, end in the 

 lower border of the coronary sinus. The oblique vein descends 



