Four Heart Treatments Questioned In Studies
By RON WINSLOW
Four strategies commonly used to treat cardiovascular disease—ranging from a $10,000-plus procedure for preventing strokes to a generic pill that costs a quarter—turn out in recent studies to have little benefit for patients.
The findings suggest that doctors and patients should consider alternatives to the strategies where they exist. They also reflect a persistent phenomenon in medicine where doctors and patients embrace new technology only to find that it may not be good medicine once exposed to rigorous testing.
Disappointing Results
In recent studies, several common heart treatments were found to have little benefit. They include:
- PFO Closure: A device that closes a tiny hole in the heart called a PFO proved no better than standard blood-thinning drugs to prevent recurrent strokes in patients who have already suffered a stroke or mini-stroke of unknown cause.
- Protecting the Kidney: A 25-cent pill called acetylcysteine is often given to patients undergoing diagnostic X-rays of their coronary arteries to prevent contrast dye used in the procedures from damaging kidneys. A 2,300-patient study found it doesn't work.
- Double Dose of Plavix: Doctors often double the dose of the blood-thinner Plavix to prevent clots from developing in patients whose diseased heart arteries are propped open with drug-coated stents and who don't sufficiently respond to the standard Plavix dose. A recent study found two pills aren't better than one.
- Monitoring Heart-Failure Symptoms: Having congestive heart failure patients report their weight and symptoms to a doctor daily via telephone was hoped to prevent frequent hospital admissions. A 1,653-patient study found no benefit.
One of the treatments—a procedure called a PFO closure in which a device is deployed to seal a tiny hole in the heart—is performed thousands of times a year in an effort to prevent recurrent strokes in patients who have previously suffered a stroke of unknown cause. But a 900-patient randomized study found it performed no better than standard blood-thinning medicines in preventing such events and that it was associated with complications not seen with the drugs.
In another large study, asking patients with congestive heart failure to provide doctors and nurses with their daily weight and other symptoms over a special telephone monitoring system failed in its goal to improve survival or reduce frequent hospital readmissions. Controlled clinical trials showed that doubling the dose of the popular blood thinner Plavix for patients who don't respond adequately to the standard dose and a pill to protect kidneys from potential harm during heart x-ray exams also provided little benefit. The studies were presented at the recent scientific meeting of the American Heart Association in Chicago.
"There are so many situations where we assume benefit and it doesn't pan out," says Harlan Krumholz, a cardiologist at Yale University, New Haven, Conn., and senior author of the paper evaluating tele-monitoring of heart failure patients. "We don't have the luxury of doing things that make sense without knowing whether they work."
Such findings don't necessarily rule out the value of tests and treatments for some patients. But researchers say they raise a yellow flag for doctors and patients eager to embrace new approaches before they are carefully studied. Curtailing routine use of widely adopted strategies shown to have little benefit, researchers add, would spare patients the burden of ineffective and potentially harmful treatments and avoid wasteful health-care spending.
"More care isn't necessarily better care, and the latest high-tech procedure may not be an advantage" for patients, says Raymond Gibbons, a cardiologist at Mayo Clinic, Rochester Minn., and past president of the American Heart Association.
Here's a closer look at the four strategies that recently failed to show benefit.
PFO Closure: PFO stands for patent foramen ovale, a small hole in the wall that divides the heart into left and right chambers. Everyone has one in the womb.
In up to 25% of people, the PFO fails to fully close after birth. While the health consequences aren't fully understood, PFOs are common among people under 60 who suffer strokes for which a cause can't be determined. A leading theory is that clots that form elsewhere in the body reach the right side of the heart, squeeze through the PFO into the left side from where they can travel to the brain.
In recent years, the idea fueled rapid adoption of devices to deploy PFO patches. Between 1998 and 2004, use of the devices increased 50-fold in the U.S. to more than 10,000 patients a year, according to an article in the Journal of the American Medical Association in 2008. The devices haven't been approved by the U.S. Food and Drug Administration for preventing strokes.
At the recent cardiology meeting, Anthony J. Furlan, chairman of neurology at University Hospitals and Case Western University School of Medicine, Cleveland said a 909-patient randomized study showing that the device was no better than regimens of aspirin and the blood thinner warfarin in preventing stroke while it was associated with a higher complication rate. "The study will put the brakes on" the common use of the technology for stroke prevention, Dr. Furlan says.
Monitoring Heart-Failure Patients: Hospitals are under growing pressure to reduce readmissions for congestive heart failure. It is the federal Medicare program's most expensive diagnosis with the cost of potentially preventable admissions amounting to about $12 billion a year. Several small studies have found that daily monitoring of weight and other symptoms can lead to quick adjustments to a patient's diet or medication and prevent the need for hospital stays. But when Yale's Dr. Krumholz and his colleagues tested the idea in a 1,653-patient study, they found no significant reduction in readmissions or improvement in survival.
"I don't think you want to throw out an entire strategy because of a couple of trials," says Dr, Krumholz, whose study was published last week in the New England Journal of Medicine. "But just merely monitoring these patients and reacting seems to be insufficient. You need a restructuring of how you're managing chronic disease."
Double-the-dose: Plavix is widely used to prevent problems such as heart attacks in patients implanted with drug-coated stents that prop open diseased arteries. But as many as 40% of people don't respond sufficiently. Small studies suggest that doubling the dose may compensate, prompting many doctors to adopt the approach.
But when Matthew Price, a cardiologist at Scripps Clinic, La Jolla, Calif., and colleagues tested it in a study of 2,214 poor responders to Plavix, two pills weren't better than one, he says. One alternative is another drug, Prasugrel; a third pill, Brillinta, is awaiting a decision on marketing approval at the FDA. Doctors are especially eager to find ways to make Plavix effective in as many patients as possible because it loses U.S. patent protection in 2012 and would be cheaper than the other available agents.
Protect the kidney: Several million patients undergo x-ray tests calls coronary angiograms each year to check for arterial blockages that could lead to heart attacks. Contrast dye used to enhance the images can wreak havoc with kidneys, especially in diabetics or in patients with already weakened kidneys. In 2000, the New England Journal of Medicine published a small study suggesting the generic drug acetylcysteine was especially effective in protecting kidneys against damage from the dye. But the study wasn't considered definitive. The four-pill regimen is cheap—it costs about $1—and has no apparent side effects.
Now, a 2,300-patient Brazilian study has shown no benefit. Brahmajee Nallamothu, a cardiologist at University of Michigan Health System, says while most patients who suffer ill effects from the dye recover, the findings underscore the need to use dye sparingly and make sure patients have adequate fluids when they undergo the procedure.
"It shouldn't take 10 years from a 100-patient study to a definitive trial," Dr. Nallamothu adds. "That's a gap where we can do better in the future."
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