Heart valve called the "semilunar valves". These two arteries receive blood from the ventricles and their semilunar valves permit blood to be forced into the arteries, and prevent backflow from the arteries into the ventricles. These valves do not have chordae tendineae, and are more similar to the valves in veins than they are to the atrioventricular valves. The closure of the semilunar valves causes the second heart sound. The aortic valve, which has three cusps, lies between the left ventricle and the aorta. During ventricular systole, pressure rises in the left ventricle and when it is greater than the pressure in
Artificial heart portable driver to power the heart with pulses of air. The drivers also monitor blood flow for each ventricle. Another U.S. team has a prototype called the 2005 MagScrew Total Artificial Heart. Teams in Japan and South Korea are also racing to produce similar devices. The Cleveland Heart is a continuous-flow total artificial heart (CFTAH) By combining its valved ventricles with the control technology and roller screw developed at Penn State, AbioMed has designed a smaller, more stable heart, the AbioCor II. This pump, which should be implantable in most men and 50% of women with a life span of