THE ROLE OF NOTCH1 IN AORTIC VALVE DISEASE 1
How does the heart work?
The human heart is made up of four chambers (left image). Each chamber is separated by valves (right image). Deoxygenated blood flows into the right atrium from systemic tissue. This blood then moves through the tricuspid valve and into the right ventricle. From there, deoxygenated blood is pushed through the pulmonary valve and to the lungs where it absorbs oxygen. Oxygenated blood flows back to the heart and drains into the left atrium. It then moves through the mitral valve and into the left ventricle. Once sufficient pressure has built up, muscles of the left ventricle push blood through the aortic valve to the rest of the bodily tissues [1]. The heart functions through mechanical and electrical impulses to supply our body and brain with the oxygen it needs to survive. Congenital heart diseases like Aortic Valve Disease 1 (AoVD1) threaten this essential and nuanced system.
What happens in Aortic Valve Disease?
Aortic valve disease 1 (AoVD1) is a group of congenital heart malformations that affect the main valve through which blood is pumped from the heart to the rest of the body. AoVD1 manifests in three main phenotypes: A) Calcification [2 and left image], in which mineral deposits cause valve hardening B) Regurgitation/insufficiency [3 and middle image], in which blood leaks backwards into the heart and C) Bicuspid aortic valve [4 and right image], in which the valve itself forms in a bileaflet instead of trileaflet manner. These phenotypes create strain on the heart that accrues over an affected individuals lifetime. Bicuspid aortic valve (BAV) patients present with a heart murmur and can be monitored by echocardiogram until valve replacement is necessary. AoVD1 is often characterized by chest pain/tightness, shortness of breath, fainting, and changes in eating habits or weight in children. If left unmonitored and untreated, AoVD1 can be life threatening [5].