Heart walls of the heart to valves by cartilaginous connections called chordae tendinae. These muscles prevent the valves from falling too far back when they close. During the relaxation phase of the cardiac cycle, the papillary muscles are also relaxed and the tension on the chordae tendineae is slight. As the heart chambers contract, so do the papillary muscles. This creates tension on the chordae tendineae, helping to hold the cusps of the atrioventricular valves in place and preventing them from being blown back into the atria. Two additional semilunar valves sit at the exit of each of the ventricles. The
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