Contribution to the study of the arterial vascularization of the sinus

Abstract

The irrigation of the sinus node in Hereford cattle was observed in 50 adults (25 males and 25 females), slaughtered in PeIotas, BR. The results obtained allowed us to come to the following conclusions: 1) The portion occupied by the sinus node is more frequently only by the ramus proximalis atrii sinistri in 49 (98,C% ± 2.0) hearts; 2) The irrigation of the nodal tissue is realized only by the ramus proximalis atrii dextri in 1 (2.0% ± 2.0) piece; 3) arterial anastomoses, in which the vessels responsible for the arterial irrigation of the sinus node were registered 242 times in all the 50 organs: 4) When the sinus node is exclusively nourished by the branches originated from the ramus circunflexus sinister or of the A. coronaria sinistra, or of the A coronaria dextra, there were statistical significant differences between Hereford cattle and Zebu Cross, Holstein or Gir Cattle.