Thursday, 18 Jul 2013 02:30 PM

By Charlotte Libov

 

Researchers in France recently announced they would begin human testing of an artificial heart that is in part fashioned from cow tissue. The hope is that the new device will prove comparable to a natural human heart in pumping efficiency and durability.

 

“This is a very promising development,” says Chauncey Crandall, M.D. “There are thousands of people on waiting lists for new hearts who die before they can get them – and that’s only the tip of the problem.

 

“Many people become so weakened by heart disease that they can no longer work or perform other functions of daily life. In essence, they are cardiac cripples. An effective artificial heart could be a lifesaver for many of these patients.” Dr. Crandall heads the cardiac transplant unit at the world-renowned Palm Beach Cardiovascular Clinic.

 

There are far too few donor hearts to meet the demand for transplants. In the U.S., some 100,000 people are on transplant lists, but only about 4,000 hearts a year are available. This means that many thousands die waiting for a new heart.

 

The new artificial heart, developed by a Paris-based biotech company called Carmat, is the latest entry in a decades-long effort. “We’ve been able to get technology to the level that we can mechanically recreate the heart with microprocessors so that it works effectively. But the persistence of blood clots has always been the problem, because they can travel to the brain and cause a stroke,” said Dr. Crandall, author of the Heart Health Report.

 

“Scientists are looking at ways to use natural materials in place of artificial ones. That is where this technology is going.”

 

The Carmat heart uses cow tissue instead of artificial materials like plastic to line areas of the heart that come into contact with human blood. Scientists believe this will mean it will have fewer problems with clotting.

 

The device has so far gotten excellent results in animals. Human testing has been approved in four countries and is expected to begin soon. Besides the clotting issue, doctors want to test the durability of the Carmat heart. To go into widespread use, it must last at least five years, say researchers.

Dr. Crandall said his optimism about the device stems in part from the fact that Alain Carpentier, a co-founder and the scientific director of Carmat, developed the new heart.

 

“He is the cardiac surgeon who pioneered the use of cow valves in humans and they have been used successfully for 20 years. So this new device is not only innovative, but it has a track record,” Dr. Crandall said.

 

The Carmat heart is a two-chambered device, each divided by a membrane. The side of the membrane that comes in contact with blood is lined with cow tissue, the other with polyurethane. The heart is powered by a battery pack worn outside the body.

 

The heart has been approved for clinical trials in Belgium, Poland, Saudi Arabia, and Slovenia. Carmat is waiting for the results in these countries before pursuing approval in the U.S., company officials have said.

 

The Carmat device may not prove to be the ultimate solution to the heart shortage because it is large and may not be durable enough, says Dr. Crandall. However, it may be a breakthrough step toward that goal.

 

“This is a very promising technology, and I foresee the day when we will have a device that is small and durable enough to truly be an artificial heart,” he said.