Original article: cardiovascularThe congenitally bicuspid aortic valve: how does it function? Why does it fail?☆
Section snippets
Material and methods
Our observations were done on three cryopreserved then thawed aortic CBAVs from humans who died of noncardiac causes.
The roots were distally cannulated and pressurized to 80 mm Hg and photographed, silicone molds were prepared, and to determine their dynamic morphology and function in a left-heart simulator (Vivitro Systems, Vancouver, Canada), primed with 38% glycerol. Flow was set at 4 L/min, the aortic pressures at 120/80 mm Hg, and the pulse rate to 72 beats/min.
Pressure gradients across
Results
Valve A was from a 10-year-old boy. The view from its aortic aspect revealed one leaflet with a prominent raphe and the other (noncoronary) with a prominence near the center of the coaptation line. The raphe, as it passed the width of the cusp, became both thicker and wider at the base. It was formed of collagen cords merging from opposing sides oriented at 90°. The free edge, instead of being suspended by commissures, was attached 3 to 4 mm off the sinotubular ridge and closed in a form of a
Comment
The CBAV requires several compensatory mechanisms to be able to function appropriately. Some of these have been identified in our observations.
The anatomical length of the leaflet edges is constant but their “functional” length must change; to match the geometry of full closure and opening, their gradual folding and unfolding is a necessity in the process. As opposed to the normal tricuspid aortic valve, the folding is not only excessive, but some folds and creases persist throughout the
References (6)
- et al.
Comparison of age, gender, number of aortic cusps, concomitant coronary artery bypass grafting, and magnitude of left ventricular-systemic arterial peak systolic gradient in adults having aortic valve replacement for isolated valve stenosis
Am J Cardiol
(1997) The congenitally bicuspid aortic valvea study of 85 autopsy cases
Am J Cardiol
(1970)- et al.
Role of sinus wall compliance in the aortic leaflet function
Am J Card
(1999)
Cited by (0)
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Presented at the Thirty-ninth Annual Meeting of The Society of Thoracic Surgeons, San Diego, CA, Jan 31–Feb 2, 2003.