D2I2.
congenital

Bicuspid aortic valve

Bicuspid valve (BAV) is a form of heart disease in which two of the leaflets of the aortic valve fuse during development in the womb resulting in a two-leaflet (bicuspid) valve instead of the normal three-leaflet (tricuspid) valve. BAV is the most common cause of heart disease present at birth and affects approximately 1.3% of adults. Normally, the mitral valve is the only bicuspid valve and this is situated between the heart's left atrium and left . Heart valves play a crucial role in ensuring the unidirectional flow of blood from the atria to the ventricles, or from the ventricle to the aorta or trunk. BAV is normally inherited.

Underlined words are explained — tap any of them.

Plain-language summary adapted from Wikipedia. Not medical advice.