Aortic valve stenosis
Aortic valve calcification is a condition in which calcium deposits form on the aortic valve in the heart. These deposits can cause narrowing at the opening of the aortic valve. This narrowing can become severe enough to reduce blood flow through the aortic valve, a condition called aortic valve stenosis. Calcification and stenosis generally affect people older than age 65 (2-3% after 65 y old).
Main causes of aortic valve stenosis
1. Aortic stenosis may be the end-stage result of the age-related degenerative calcific lesion, also known as senile or sclerocalcific aortic stenosis, that affects about 10-20% of people over 75. Clinically, aortic valve stenosis is often asymptomatic until it reaches a critical narrowing stage with obstruction of the left ventricle outflow that can no longer be compensated by a concomitant hypertrophy.
2. Aortic stenosis, may be congenital (bicuspid) in origin. In this case, the abnormal valve architecture makes its leaflets susceptible to otherwise ordinary haemodynamic stress, ultimately leading to valvular thickening, calcification, increased rigidity and narrowing of the aortic orifice.
3. Aortic stenosis may occur as a consequence of rheumatic endocarditis of the aortic leaflets with consequent commissural fusion. The highest incidence is observed in developing countries.
Structural BioprosthesisDegeneration (SVD)
All biological valve are subjected of SVD (porcine and bovine bioprosthesis). Structural Bioprosthesis Degeneration occurs at 10% in 10 years in elderly recipients.
SVD diagnosis by cardiacultrasound
The best way to assess the structural and functional changes of bioprostheses after implantation is echocardiography examination.
Treatment of SVD
Exemple of Structural Valve Degeneration. (a,d and e) Calcific deposits present in leaflet and at commissures, the leaflets are also thickened. (b and c ) Pannus formation (pannus is mainly formed of collagen and elastic fibrous tissue accompanied by endothelial cells, chronic inflammatory cell infiltration and myofibroblasts).