Movie legend Elizabeth Taylor, 78, took to the micro-blogging site Twitter last October and announced she was undergoing an experimental heart procedure.
"It's very new and involves repairing my leaky valve using a clip device, without open heart surgery, so that my heart will function better," she wrote. Heart device aficionados immediately recognized the device as the MitraClip, from Abbott Laboratories, which is not yet approved by the Food and Drug Administration. Taylor was apparently in one of several ongoing research studies. Two days after the surgery she twittered again: "It's like having a brand new ticker."
If approved, the device would enable surgeons to repair leaky heart valves without the need for full-blown open heart surgery. They could do it through two tiny keyholes instead. In a study presented at the recent meeting of the American College of Cardiology, the MitraClip didn't seem as effective at preventing blood from leaking through the mitral valve that separates the top-left chamber of the heart from the bottom as the traditional method opening up the chest and doing surgery. But it does involve fewer complications. It may be an option for patients in whom open-heart surgery is deemed too risky.
"We need to have more data, but I'm impressed with the early results," says Sidney Smith, director of the Center for Cardiovascular Science and Medicine at the University of North Carolina. "As experience with the technology improves there's the potential that a lot of patients who are not good candidates for surgery may well benefit from this."
Deaths from cardiovascular disease have plummeted 30 per cent over the past decade thanks to drugs to lower blood pressure and cholesterol and devices that help get patients through the danger period after a heart attack or sudden heart stoppage. But heart disease is still America's top killer, claiming 630,000 lives annually. Experimental medicines are having trouble making a further dent on other common, costly, and dangerous problems like heart failure, heart valve disease and various heart rhythm problems. For some patients, new gadgets being developed by the medical device industry may have a big impact.
One of the biggest unsolved problems is heart failure, in which the heart's muscle becomes too weak to pump blood. It affects nearly 6 million Americans. Fluid buildup fills the lungs, making patients feel they are drowning. Old drugs like beta blockers and diuretics (water pills) can help prevent the buildup and improve survival. But once patients get sick enough to end up in the hospital, they come back again and again. Almost all attempts at developing new drugs have failed. Treating heart failure costs Medicare $30 billion a year, making it one of the most expensive diseases for the government.
Last year, researchers proved that a new kind of medical implant could reduce heart failure hospitalizations 40 per cent, according to the results of a 1,820-patient study. Hearts that are failing aren't just weaker, they pump with the wrong rhythm. The cardiac resynchronization therapy (CRT) involves implanting a special type of pacemaker that uses electric charges to keep the heart's chambers pumping in rhythm with each other. Arthur Moss of Rochester University, the electrophysiologist who ran the trial, notes that the device was "dramatically more effective" in women than in men -- a good thing, since women are harder hit by heart failure.
In the wake of the study, a panel of advisors to the Food and Drug Administration recently recommended the CRTs be approved for as many as 4 million more patients.
CRT devices are made by Medtronic, St. Jude Medical and Boston Scientific, which funded Moss' study. In an ironic twist, all of Boston Scientific's heart rhythm devices were recently temporarily taken off the market due to a regulatory snafu that could drag on for many weeks.
For people with severe heart failure who need a transplant, there are now new devices to keep them alive while they wait. The machines are called left ventricular assist devices and help a weak heart pump blood. Last year, one such external device, HeartMate from Thoratec, was also approved for heart patients who are so old or sick they are not candidates for a transplant. Meanwhile, Abiomed in Massachusetts sells a smaller heart-assist pump that can be implanted inside the body using a catheter.
Exactly what goes wrong to cause life-threatening electrical disturbances in the heart is one of the big mysteries of cardiology. More than 200,000 people every year suffer sudden cardiac death, in which a sudden stoppage of the heart kills. In people at high risk, such as those with heart failure, an implantable cardioverter defibrillator (ICD) can restart the heart with a shock. But much more work needs to be done to find genetic clues or other methods for identifying people who might be harmed.
Two-and-a-half million people have atrial fibrillation, a disorder in which the heart occasionally flutters instead of beating, causing dizziness. Sufferers can be highly productive, even athletic (basketball legends Jerry West and Bill Bradley both had a-fib). But the fluttering can cause blood clots that lead to strokes, necessitating the use of blood thinners in many patients. Right now the only option is Coumadin, an old drug whose dose must be carefully controlled, but new and potentially better options are being developed by Boehringer Ingelheim, Johnson & Johnson, Pfizer, Merck, and most other drug companies.
Preventing strokes, however, doesn't make patients feel better day-to-day, and drugs to control heart rhythms have serious side effects that limit their use. A new surgical procedure called catheter ablation holds hope here. In the procedure, parts of the heart that are causing the rhythm problems are destroyed. In one 245-person trial of a Medtronic ablation device, 70 per cent of patients who received ablation went a year without an a-fib episode, compared with 7 per cent of those on drugs.
Clyde Yancy of the Baylor College of Medicine, the current president of the American Heart Association, cautions that it is not clear if patients who get ablation can go off their blood thinners. Nor is it clear that the response is durable. Still, he is hopeful. "As we continue to deal with this burden of atrial fibrillation, it looks like this technology is out of the box," he says.
Eighty-one million Americans, one in three adults, have some form of cardiovascular disease, including risk factors like high blood pressure and high cholesterol.
