Former Vice President Dick Cheney, 69, who underwent surgery last week to implant a pump to assist his heart, may be only one step away from a heart transplant, according to cardiac experts. They say he could find himself on a wait list for "months or years."
Cardiologists say the former vice president has a left ventricular assist device (LVAD), which is often used as a so-called "destination" or permanent device, but in his case is likely a "bridge" that will keep him alive until he can receive a transplant.
Many patients with such pumps are described as not having a pulse, because the continuous flow of the LVAD -- much like water circulating in a fish tank rather than pumping like a heart -- can make the pulse indiscernible.
But heart experts say that only patients who depend on LVADs for 100 percent of their circulation are essentially without a heartbeat. Cheney's device is likely doing 30 to 60 percent of the heart's work.
"The HeartMate II is used in situations where the patient's native heart continues to pump, but not normally and effectively," said Dr. Timothy J. Gardner, a heart surgeon at Christiana Care Health System in Wilmington, Delaware, and past president of the American Heart Association.
"But it's enough to have some detectable pulse, " he said.
The LVAD is implanted next to the heart to help its main pumping chamber, the left ventricle, pump blood through the body. Such devices are used mainly for short periods, to buy potential transplant candidates time as they await a donor organ.
"It's a really good strategy," said Dr. William Abraham, director of the division of cardiovascular medicine at Ohio State University, which does 75 to 100 implantations a year.
"It's reserved for people who have end-stage heart failure, and advanced and heroic therapies have been tried, and after folks have optimized evidence-based and guideline-recommended drug therapies," he said. "Their heart conditions have progressed to a state where the mortality risk is very high and they turn to LVADs and transplants."
Cheney's doctors said his operation went well and he is now recuperating.
The surgery took place at Inova Fairfax Heart and Vascular Institute in northern Virginia.
The reason he did not go to his usual medical home at The George Washington University Hospital is that LVADs are only implanted at two area facilities: Inova Fairfax and Washington Hospital Center.
Cheney has a long history of heart problems. He has had five heart attacks, the first in 1978 when he was just 37 years old, and the fourth in November 2000, after he and former President George W. Bush were elected to the White House.
"We know that he has severe ischemic coronary heart disease that has done a lot of damage to his left ventricle," said Abraham. "It's been described as a relatively small pump and [doctors] have implied he will be up and fully functional soon. That makes sense that it's an LVAD. Other devices are far more intrusive and the recovery is much slower."
The device pushes blood from the left ventricle into the ascending aorta -- the beginning of the major blood vessel that supplies the rest of the body.