Alan meets David Lederman, inventor of a promising
new mechanical heart
been nearly two decades since the world watched Barney Clark
struggle for 112 days with his artificial heart, the Jarvik
7. Clark's four-month ordeal, during which he was bound to
a refrigerator-sized air pump and suffered four clot-induced
stokes, cooled enthusiasm for artificial hearts.
But research on mechanical hearts has made giant leaps forward
in recent years. In 1993, Michael Dorsey was one of the thousands
of patients in desperate need of a heart transplant. As he
awaited a donor, Michael's doctors at the Inova Hospital in
Virginia fitted him with a Heartmate mechanical assist device.
to his left ventricle and aorta, the pump took over much of
the work of his ailing heart. Unlike the Jarvik 7, the Heartmate's
battery pack and portable air pump allowed Michael some degree
of freedom. But like Clark, Michael had wires and tubes protruding
from his belly, an uncomfortable and vulnerable condition.
ABIOMED heart may one day save up to 45,000 Americans
a new generation of mechanical devices is smaller and more
efficient than ever. Alan visits a research lab where a fully
implantable, permanent artificial heart is in the late stages
of testing. Like a real human heart, the ABIOMED model has
two pumping chambers and valves that regulate blood flow.
This new device runs on a battery that can be recharged through
the skin, so no tubes and wires need pass through the body
ABIOMED heart is already hard at work inside livestock, whose
vital statistics the Massachusetts-based scientists monitor
daily. Plans are underway for the first human trials to start
more on this topic, see the web feature:
"Searching for a Substitute"