Objective To assess the influence of mimic cardiac rate on hydrodynamics of different mechanical prosthetic cardiac valves. Methods US-made CarboMedics bileaflet valve, China-made Jiuling bileaflet valve and C-L tilti...Objective To assess the influence of mimic cardiac rate on hydrodynamics of different mechanical prosthetic cardiac valves. Methods US-made CarboMedics bileaflet valve, China-made Jiuling bileaflet valve and C-L tilting disc valve were tested via a pulsatile flow simulator in the aortic position. Testing conditions were set at mimic cardiac rates of 55 bpm, 75 bpm, 100 bpm with a constant mimic cardiac output of 4 L/min. The mean pressure differences (ΔP), leakage volumes (LEV) and closing volumes (CLV) across each valve, and effective orifice areas (EOA) were analyzed. Results Within physiological range, ΔP, LEV, and CLV decreased as mimic cardiac rate increased, with a large extent of variance. EOA increased along with an increase in mimic cardiac rate. It was a different response in terms of cardiac rate alteration for different types of mechanical prosthetic cardiac valves. Conclusion Mimic cardiac rate change affects hydrodynamics of mechanical prosthetic cardiac valves. Within physiological range, the hydrodynamic of prosthetic bileaflet valve is better than that of tilting disc valve.展开更多
Valvular heart disease is a pathologic process involving one or more of the four valves(aortic,pulmonary,mitral and tricuspid)of the heart typified by stenosis or regurgitation and leading to patient symptoms.The most...Valvular heart disease is a pathologic process involving one or more of the four valves(aortic,pulmonary,mitral and tricuspid)of the heart typified by stenosis or regurgitation and leading to patient symptoms.The most common causes are tissue degeneration,rheumatic fever and congenital heart diseases.Aortic valve replacement(AVR)using either mechanical or bioprosthetic(tissue)valves via open-heart surgical展开更多
文摘Objective To assess the influence of mimic cardiac rate on hydrodynamics of different mechanical prosthetic cardiac valves. Methods US-made CarboMedics bileaflet valve, China-made Jiuling bileaflet valve and C-L tilting disc valve were tested via a pulsatile flow simulator in the aortic position. Testing conditions were set at mimic cardiac rates of 55 bpm, 75 bpm, 100 bpm with a constant mimic cardiac output of 4 L/min. The mean pressure differences (ΔP), leakage volumes (LEV) and closing volumes (CLV) across each valve, and effective orifice areas (EOA) were analyzed. Results Within physiological range, ΔP, LEV, and CLV decreased as mimic cardiac rate increased, with a large extent of variance. EOA increased along with an increase in mimic cardiac rate. It was a different response in terms of cardiac rate alteration for different types of mechanical prosthetic cardiac valves. Conclusion Mimic cardiac rate change affects hydrodynamics of mechanical prosthetic cardiac valves. Within physiological range, the hydrodynamic of prosthetic bileaflet valve is better than that of tilting disc valve.
基金supported by the Department of Anesthesiology and Pain Medicine,University of California Davis Health
文摘Valvular heart disease is a pathologic process involving one or more of the four valves(aortic,pulmonary,mitral and tricuspid)of the heart typified by stenosis or regurgitation and leading to patient symptoms.The most common causes are tissue degeneration,rheumatic fever and congenital heart diseases.Aortic valve replacement(AVR)using either mechanical or bioprosthetic(tissue)valves via open-heart surgical