Question
Identify the type of prosthetic heart valve shown in the photograph below ?
A. Bi-leaflet mechanical.
B. Tri leaflet mechanical.
C. Ball and cage mechanical.
D. Tilting disc mechanical.
Show Answer
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Correct Answer » C
Explanation
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Ans.C. Ball and cage mechanical
The first artificial heart valve was the caged-ball, which utilizes a metal cage to house a silicone elastomer ball. When blood pressure in the chamber of the heart exceeds that of the pressure on the outside of the chamber the ball is pushed against the cage and allows blood to flow. At the completion of the heart’s contraction, the pressure inside the chamber drops and is lower than beyond the valve, so the ball moves back against the base of the valve forming a seal
Caged ball valves have a high tendency to forming blood clots, so the patient must have a high degree of anti-coagulation, usually with a target INR of 2.5-3.5.
