[Arterial vascularization of the sino-atrial and atrio-ventricular nodes and frequency of coronary artery branches in Papio Erxleben, 1777].

The arterial blood supply to the sino-atrial (S-A) and atrio-ventricular (A-V) nodes was studied in 63 baboon hearts (Papio cynocephalus and Papio hamadryas). The arterial coronary injection was made with latex neoprene (23 hearts), a latex and lead oxide mixture (30 hearts) and polyester resin (10 hearts) for dissection, radiographic and corrosion cast studies, respectively. The S-A artery is a long recurrent left coronary branch (92.1%) or an ascendant less long right coronary branch (7.9%). The A-V arteries were 2 or 3 small branches of the interventricular posterior artery originating from the right or the left with the same frequency as in man. The percent distribution of the other coronary branches was similar to that observed in man.