Is cardiac valves really (a)vascular structures ?

Though heart is known primarily as a pump, it is the four cardiac valves that ensures the critical , non-stop unidirectional flow that sustain the circulation . It is to be recalled these valves originate in the very early days of cardiac development when the primitive heart tube loops , even as the chambers expand from primitive ventricle. Mesenchymal differentiation controlled by various genes that cleaves the valve from myocardial tissue. While heart by itself is the supreme vascular organ ,  its surprising  few structures inside the heart , like the valves are quiet avascular ( or is it really so ?) The valves that beat average of 30 billion time in life time ,seem  to get its nourishment from Nowhere ? Layers of heart valve    Image source : Huk D., Lincoln J. (2017) Oxidative Stress in Cardiac Valve Development. In: Rodriguez-Porcel M., Chade A., Miller J. (eds) Studies on Atherosclerosis. Oxidative Stress in Applied Basic Research and Clinical Practice. Humana Press, Boston, MA It’s primarily made up of  complex stratified connective tissue covered by endothelial cells with intervening interstitial cells. The extracellular matrix (ECM) layers are rich in elastin proteoglycan (spongiosa) and collagen (fibrosa). It has been found myocytes and dormant fibroblasts are scattered in the valve leaflets. This forms the basis of focal origins of  Cuspal Ventricular tachycardia J Cardiovasc Electrophysiol. 2002 Jun;13(6):551-6.  from electricaly activated...
Source: Dr.S.Venkatesan MD - Category: Cardiology Authors: Tags: cardiac embryology Embryology : Heart valve development Infective endocarditis : Pathology valvular heart disease blood supply to heart valves hematogenous spread of infective endocarditis how bacteria reach mitral valve in infective endocardi Source Type: blogs