part of connected to right cardiac atrium heart blood vessel venous blood vessel systemic venous system coronary sinus NCIT:C32378 sinus coronarius Wikipedia:Coronary_sinus The short trunk that recieves most of the cardiac veins carrying the blood from the myocardium and delivers it to the right atrium, with the sinoatrial connection occurring between the inferior vena cava and the atrioventricular orifice. EHDAA2:0000320 EHDAA:9884 FMA:4706 SCTID:244386006 sinus coronarius