what are the atrioventricular valves
The atrioventricular (AV) valves are the two heart valves that sit between the atria (upper chambers) and ventricles (lower chambers): the tricuspid valve on the right side and the mitral (bicuspid) valve on the left side. They act like one‑way doors, opening to let blood flow from atria into ventricles and closing during ventricular contraction so blood cannot leak backward into the atria.
Quick Scoop
- What they are:
- Two flap-like valves made of cusps/leaflets and supporting structures (like chordae tendineae and papillary muscles) that separate atria from ventricles.
* Right side: tricuspid valve (three cusps) between right atrium and right ventricle.
* Left side: mitral/bicuspid valve (two cusps) between left atrium and left ventricle.
- What they do:
- Open in diastole: When the heart relaxes (diastole) and atria contract slightly, they open so blood can fill the ventricles.
2. **Close in systole:** When ventricles contract (systole), they snap shut to prevent backflow into the atria and ensure blood is ejected forward through the semilunar valves (aortic and pulmonary).
3. **Maintain one‑way flow:** This one‑way mechanism preserves efficient circulation and normal cardiac output.
- Why they matter:
- Proper AV valve function is essential for effective pumping and normal heart sounds (their closure produces the first heart sound, S1).
* Disease of these valves (like stenosis or regurgitation) can lead to heart failure symptoms because blood either cannot get through easily or leaks backward.
In short: atrioventricular valves = tricuspid + mitral, the heart’s gatekeepers that let blood move down into the ventricles but block it from rushing back up.
Information gathered from public forums or data available on the internet and portrayed here.