Histologic analysis of the right atrioventricular junction in the adult human heart.
ABSTRACT The human tricuspid valve is conventionally thought to have a fibrous annulus in the septal region. The study aim was to conduct morphological and histological analyses of the right atrioventricular junction (RAVJ), in particular to investigate the fibrous/collagenous content of this structure in the adult human heart.
Twelve human hearts from patients who died after cardiac surgery and underwent autopsy were included in the study. Rigid exclusion criteria were practiced to ensure that the hearts studied were not subject to ventricular dilatation or hypertrophy prior to surgery, or had undergone valvular surgery. Gross examination of the RAVJ was performed and the entire circumference of the RAVJ sectioned longitudinally at 5 mm intervals; the tissues were then fixed in 10% neutral buffered formalin for 24 h. All sections were then stained with hematoxylin and eosin and elastic van Geison stains.
There were no significant amounts of fibrous or collagenous structures along the free wall segment of the RAVJ. Muscular bars, measuring about 2-4 mm in diameter, were seen to run between the wall of the right ventricle and the RAVJ on its ventricular aspect. The relationship between the base of the tricuspid valve leaflet to the right atrial and right ventricular muscle head varied significantly within, and between, hearts.
While the septal aspect of the RAVJ has scant fibrous tissue, the majority of its free wall segment is devoid of fibrous tissue. Right ventricular muscle bridges are inserted into the RAVJ, the functional significance of which, both in normal hearts and in the pathogenesis of functional tricuspid regurgitation, requires further investigation.
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ABSTRACT: A thorough understanding of valvar anatomy is essential for design engineers and clinicians in the development and/or employment of improved technologies or therapies for treating valvar pathologies. There are two arterial valves in the human heart-pulmonary and aortic valves. Both are complex structures whose normal anatomical components can vary greatly between individuals. We discuss the anatomy, pathology, and challenges relating to transcatheter and surgical repair/replacement of the arterial valves in a translational manner. The high prevalence of aortic valvar pathologies in the burgeoning elderly population, coupled with poor clinical outcomes for patients who go untreated, has resulted in prolific spending in the research and development of more effective and less traumatic therapies. The accelerated development of therapies for treating arterial valves has been guided by anatomical information gathered from high-resolution imaging technologies, which have focused attention on the need for complete understanding of arterial valvar clinical anatomies. This article is part of a JCTR special issue on Cardiac Anatomy.Journal of Cardiovascular Translational Research 01/2013; 6(2). DOI:10.1007/s12265-012-9438-8 · 2.69 Impact Factor
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ABSTRACT: A critical understanding of cardiac anatomy is essential for design engineers and clinicians with the intent of developing and/or employing improved or novel technologies or therapies for treating an impaired atrioventricular valve. Likewise, such knowledge is required for directing translational research, including initiating preclinical research, assessing the feasibility of clinical trials, and performing first-in-man procedures. There are two atrioventricular valves in the human heart, namely the tricuspid and mitral valves. Both are complex structures whose normal anatomies can vary greatly amongst individuals, and also become modified by disease processes. In this review, we discuss the anatomy, pathology, and issues related to surgical and transcatheter repair of the atrioventricular valves in a translational manner. This article is part of a JCTR special issue on Cardiac Anatomy.Journal of Cardiovascular Translational Research 01/2013; 6(2). DOI:10.1007/s12265-012-9437-9 · 2.69 Impact Factor