Skipping the Beat The “Beatless” Heart Tyler BlakeProfessor Ying Sun University of Rhode Island BME 281

“Wings that flap didn’t help mankind fly, so why must a substitute heart beat like a natural one? ‘Mother nature did the best she could’” ~Billy Cohn, researcher at Texas Heart Institute This past year a 55 year old man from Texas had the first beatless heart transplant saving him from a death doctors told him was 12 hours away; he had no pulse and was technically flat lined but was not dead.

The normal human heart works on a system using cardiac muscles: Electrical impulses tell cardiac muscles to squeeze Blood pushes through each of the heart's four chambers The pulse or “beat” allows for blood to circulate through the body efficiently Rather than using a “beating” mechanism that would mimic the body’s heart, Dr. Cohn and Dr. Frazier devised a system entirely different. They interconnected two ventricular assist devices The rotors in the devices work together to whirl around the blood in the device The device propels the blood through the vascular system in a continuous flow

Ventricular Assist Device Ventricular assist devices were invented in 1980 Recently Dick Cheney had one implanted to help with ventricular failure This past year has been the first time a complete heart was created from two assisting devices. These devices connect the ventricles to the aorta and so help each ventricle push the blood by push the blood by battery powered rotors. powered rotors.