ePrints

Sequential segmental analysis of the crocodilian heart

Lookup NU author(s): Professor Bob Anderson

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.

Abstract

© 2017 Anatomical Society. Differences between hearts of crocodilians and those of mammals and birds are only partly understood because there is no standardised approach and terminology for describing cardiac structure. Whereas most reptiles have an undivided ventricle, crocodilians have a fully septated ventricle. Their hearts, therefore, are more readily comparable with the hearts of mammals and birds. Here, we describe the heart of a crocodile (Crocodylus noliticus). We use the versatile sequential segmental approach to analysis, juxtaposing several key views of the crocodilian heart to the comparable views of human hearts. In crocodiles, the atrial and ventricular septums are complete but, unlike in placental mammals, the atrial septum is without an oval fossa. The myocardial component of the crocodilian ventricular septum dominates, but the membranous septum likely makes up a greater proportion than in any mammal. In the crocodile, the aortic trunk takes its origin from the left ventricle and is not wedged between the atrioventricular junctions. Consequently, there is a common atrioventricular junction, albeit with separate right and left atrioventricular valvar orifices. As in mammals, nonetheless, the crocodilian left atrioventricular valvar orifice is cranial to the right atrioventricular valvar orifice. By applying a method of analysis and terminology usually restricted to the human heart, we build from the considerable existing literature to show neglected and overlooked shared features, such as the offset between the left and right atrioventricular valvar orifices. Such commonalities are surprising given the substantial evolutionary divergence of the archosaur and synapsid lineages, and likely reflect evolutionarily shared morphogenetic programmes.

Publication metadata

Author(s): Cook AC, Tran V-H, Spicer DE, Rob JMH, Sridharan S, Taylor A, Anderson RH, Jensen B

Publication type: Article

Publication status: Published

Journal: Journal of Anatomy

Year: 2017

Volume: 231

Issue: 4

Pages: 484-499

Print publication date: 01/10/2017

Online publication date: 01/08/2017

Acceptance date: 27/05/2017

ISSN (print): 0021-8782

ISSN (electronic): 1469-7580

Publisher: Wiley-Blackwell

URL: https://doi.org/10.1111/joa.12661

DOI: 10.1111/joa.12661

Altmetrics

Share