Echocardiographic measurements and cardiac anatomy in healthy Western hognose snakes (Heterodon nasicus)

Abstract

This study aims to describe the most important cardiac structures in the Heterodon nasicus through echocardiography and anatomical dissection. Echocardiographic and echo-Doppler measurements were performed on twenty healthy adult Heterodon nasicus (10.10). The values of the ventricular length, aortic diameter, pulmonary trunk diameter, the mean thickness of the interventricular septum, and thicknesses of the wall of the cavum pulmonale (Cav. P) and cavum arteriosum (Cav. A), were measured. The aortic flow and pulmonary trunk flow were recorded. Two dead specimens (1.1) were dissected. The male's pulmonary trunk diameter was bigger compared to the female's in both the long and short axis. The reproductive ecology of Heterodon nasicus has yet to be fully elucidated upon, however, male territorialism and dispersal from the hibernacula, and multiple male courtships toward a single female were described, hence, the more active reproductive activity of the male and the consequent sexual selection toward a higher aerobic performance can be hypothesised. A moderate interventricular right to left shunt was noticed in the Cav. V of all the specimens, which is considered normal and should not confuse the clinician. Congenital defects, cardiomyopathies, valvulopathies, and pericardial diseases are known to occur in ophidians and other reptiles. Reliable data and profound knowledge of the anatomy and physiology of the ophidian heart are fundamental for the in vivo diagnosis of cardiac diseases in snakes.