Stroke Prevention Device Shows Promise And Perplexity Of Health Breakthroughs | KCUR

Stroke Prevention Device Shows Promise And Perplexity Of Health Breakthroughs

Jun 16, 2015

Charles Welty began seriously worrying about his heart health at the gym. The 78-year-old retired civil engineer said that while running on a treadmill, he saw something startling on the machine’s heart monitor.

“My pulse rate was undetectable,” Welty said during a recent interview in his Lenexa home. “It was so fast.”

A visit to his doctor revealed that his worries were not unfounded.  

“What was going on was not so good. And had me somewhat scared,” Welty said.

His doctor’s diagnosis: atrial fibrillation, a condition in which the heart’s chambers beat out of sync with each other.

Fortunately for Welty, a new device to help atrial fibrillation patients was approved by the Food and Drug Administration earlier this year.

The Watchman device may prove to be a life-changing breakthrough for many of patients like Welty, but it also offers a revealing look at the complexities and confusion that often accompany the introduction of new medical breakthroughs.  

A new approach

As Welty’s doctor, Ken Huber, explained recently, atrial fibrillation patients have quadruple or quintuple the risk of stroke because the irregular beating of their heart allows blood to collect in a small vestigial chamber near the top of the heart called the left atrial appendage, or LAA.

“That’s where the blood pools, and if the blood pools because it’s not moving through quickly because it’s not being ejected out, then a clot can form,” said Huber, a cardiologist at Saint Luke’s Hospital of Kansas City and a clinical professor of medicine at the University of Missouri-Kansas City. (KCUR is licensed by UMKC.)

Clots can lead to strokes when they get into blood vessels and block blood flow to the brain.

Sitting in his cramped office at Saint Luke’s, Huber displayed the tiny device that many see as a big step forward in treating atrial fibrillation patients. The Watchman, which looks like a small toy parachute, is inserted into the heart through a catheter to block off the left atrial appendage.

“You completely eliminate that appendage from the systemic circulation,” Huber said.

This approach gives cardiologists an alternative to current standard treatment. To prevent clotting, most atrial fibrillation patients take anticoagulants (also called blood thinners) like warfarin, known by brand names such as Coumadin and Jantoven. But as Huber explained, some patients experience nasty side effects from anticoagulants, including bleeding.

“There’s a whole host of reasons whereby we want to prescribe these medications, but the patients just are unable or unwilling to take them,” he said. “And so what do you do for those patients?”

Huber is well familiar with the Watchman, which is made by Boston Scientific. Saint Luke’s was one of the primary sites for The Watchman’s clinical trials.

Putting it to the test

In the trials, the Watchman was shown to be nearly as effective as warfarin in preventing blood clots. And for patients for whom blood thinners aren’t a good option, that sounds like great news.

But Clifford Kavinsky, a cardiologist who teaches at Rush University Medical Center in Chicago, notes that even after an FDA approval process that dragged out over 10 years, there are still questions about the Watchman. Chief among them: Is it safe for the patients it’s supposed to help?

“The patients that most doctors would like to use this technology in are patients who cannot take blood thinners. However, all the randomized trials only included patients who could take blood thinners,” said Kavinsky, who chairs the Structural Heart Disease Committee of The Society for Cardiovascular Angiography and Interventions.  

In fact, the FDA approved the Watchman for patients who can take blood thinners. And while it allows patients to eventually stop taking the drugs, Watchman patients must take them for 45 days after the device is inserted.

“I think it’s a little confusing, and I think this confusion is what we need to iron out,” Kavinsky said.

Evaluating how the Watchman’s costs stack up against those of warfarin is tricky too. Huber says the device itself costs from $10,000 to $15,000, and that doesn’t include the costs of the surgery and other fees. Warfarin, by contrast, has an average lifetime cost of $16,000.

But Huber, Kavinsky and other physicians say a side-by-side comparison is difficult because lifetime drug costs vary depending on how long a patient lives. And insurers may vary widely in what they’re willing to cover and how much they’re willing to pay.

Overuse?

There’s another concern that troubles some cardiologists. The FDA has approved the device for patients who have an “appropriate rationale” for not taking drugs, and according to Kavinsky, that’s pretty vague.

“When things are vague, that tends to result in overutilization,” he said.

Kavinsky said warfarin and other blood thinners will remain the standard treatment for the time being, but some patients who are good candidates for these drugs may reject them in favor of the Watchman and the prospect of being free of drugs and their possible side effects.

Moreover, doctors and hospitals could be tempted to overuse the Watchman in the way many new technologies tend to get overused, simply because they exist and offer a ready source of revenue.

Overuse of the device could lead to more medical complications and drive up the costs of care and insurance.

“That’s why we have to be very careful about developing a list of guidelines which will prescribe which (patients) would benefit the most,” Kavinsky said.

So the Society for Cardiovascular Angiography and Interventions and other medical organizations are coming up with rules on how doctors should be trained to use the Watchman.

Kavinsky says there’s no way to enforce such rules, but he’s hopeful they’ll influence insurers on when and how to cover the procedure.

Since its approval by the FDA about three months ago, Watchmans have been implanted in more than half a dozen patients at Saint Luke’s and eight more procedures are planned through July.

One of the patients who received one was Charles Welty, who, after his diagnosis, underwent the implantation procedure at the hospital.

“I feel wonderful,” Welty said, eyes twinkling. “A lot of it is mental, perhaps, but I have not had any episodes with my heart.”

Alex Smith is a reporter for KCUR, a partner in the Heartland Health Monitor team.