Vol 66, No 1 (2007)
Original article
Submitted: 2012-02-06
Published online: 2006-12-14
The anatomy of the tendon of the Infundibulum revisited
M. Loukas, R.S. Tubbs, J.L. Bright, M. Fudalej, T. Wagner, R.H. Anderson
Folia Morphol 2007;66(1):33-38.
Vol 66, No 1 (2007)
ORIGINAL ARTICLES
Submitted: 2012-02-06
Published online: 2006-12-14
Abstract
The heart is a muscular organ supported by collagenous tissue. The collagenous
tissue is condensed in certain areas to form a supporting framework, often called the fibrous skeleton. The so-called tendon of the infundibulum
has previously been described as part of this skeleton, but its structure and
incidence remain ill defined. The tendon was initially described as a strip of
fibrous tissue running between the aortic root and the pulmonary trunk. Since information on its structure is vague, we sought to evaluate its existence in 100 formalin-fixed adult human hearts obtained from subjects ranging in age from 22 to 86 years, in 20 hearts from infants and children aged from 2 months to 6 years at the time of their death and in 10 cattle hearts. We used classical macroscopic anatomical techniques to demonstrate all the possible connections between the sinuses of the aorta and the pulmonary trunk. We then supplemented the macroscopic techniques with serial transverse histological sections taken through the vascular roots, staining the sections with the haematoxylin-eosin, van Gieson, Masson trichrome and orcein staining methods. Fascial bands surrounded by connective tissue were observed in all hearts. In 80 adult hearts and in 16 neonatal hearts we found fascial bands or strips, which connected the aortic and pulmonary roots. Only in two hearts, however, were we able to identify tendon-like structures, and histology revealed that these were formed by tightly packed collagen fibres intermingled with fat, most likely due to advanced age. Thus in those cases where a "tendon" was present it was no more than condensed fascial bands joining together the apposing sinuses of the arterial trunks. In our opinion, therefore, accounts in the literature describing the "tendon of the infundibulum" as a tendinous structure connecting the aortic and pulmonary roots do not accurately represent
this anatomical structure.
Abstract
The heart is a muscular organ supported by collagenous tissue. The collagenous
tissue is condensed in certain areas to form a supporting framework, often called the fibrous skeleton. The so-called tendon of the infundibulum
has previously been described as part of this skeleton, but its structure and
incidence remain ill defined. The tendon was initially described as a strip of
fibrous tissue running between the aortic root and the pulmonary trunk. Since information on its structure is vague, we sought to evaluate its existence in 100 formalin-fixed adult human hearts obtained from subjects ranging in age from 22 to 86 years, in 20 hearts from infants and children aged from 2 months to 6 years at the time of their death and in 10 cattle hearts. We used classical macroscopic anatomical techniques to demonstrate all the possible connections between the sinuses of the aorta and the pulmonary trunk. We then supplemented the macroscopic techniques with serial transverse histological sections taken through the vascular roots, staining the sections with the haematoxylin-eosin, van Gieson, Masson trichrome and orcein staining methods. Fascial bands surrounded by connective tissue were observed in all hearts. In 80 adult hearts and in 16 neonatal hearts we found fascial bands or strips, which connected the aortic and pulmonary roots. Only in two hearts, however, were we able to identify tendon-like structures, and histology revealed that these were formed by tightly packed collagen fibres intermingled with fat, most likely due to advanced age. Thus in those cases where a "tendon" was present it was no more than condensed fascial bands joining together the apposing sinuses of the arterial trunks. In our opinion, therefore, accounts in the literature describing the "tendon of the infundibulum" as a tendinous structure connecting the aortic and pulmonary roots do not accurately represent
this anatomical structure.
Keywords
aortic root; pulmonary root; fibrous skeleton; fascial bands; heart; arterial trunks
Title
The anatomy of the tendon of the Infundibulum revisited
Journal
Folia Morphologica
Issue
Vol 66, No 1 (2007)
Article type
Original article
Pages
33-38
Published online
2006-12-14
Page views
466
Article views/downloads
1182
Bibliographic record
Folia Morphol 2007;66(1):33-38.
Keywords
aortic root
pulmonary root
fibrous skeleton
fascial bands
heart
arterial trunks
Authors
M. Loukas
R.S. Tubbs
J.L. Bright
M. Fudalej
T. Wagner
R.H. Anderson