WASHINGTON - In a radical experiment, doctors are snaking wires inside the lungs of asthma patients to essentially burn off some of the tissue that blocks their ability to breathe.
The procedure, bronchial thermoplasty, is the first attempt at a non-drug treatment for asthma.
It's not without risk. Irritating those super-sensitive airways can trigger wheezing, and no one knows the long-term effects. Nor does it promise a cure.
But the hope is that physically altering spasm-prone airways might help thousands of asthma patients breathe easier.
"People still get very sick from asthma. People still die of asthma. You'd think we'd have better control, but it seems to be escalating rather than going down," said Dr. Michael Simoff, interventional pulmonology chief at Detroit's Henry Ford Medical Center, one of 18 U.S. hospitals, and 30 worldwide, enrolling patients in the experiment.
"We have a real potential here, I think, to influence a very common disease," he said.
More than 20 million Americans have asthma, and the chronic lung disease is on the rise. While medications can be effective in preventing and treating asthma attacks, the disease kills 5,000 people every year and accounts for2 million emergency-room visits.
The thermoplasty experiment targets patients who do poorly despite multiple medications - based on evidence that overgrown muscle tissue lining air tubes inside the lungs is one of asthma's underlying causes.
So-called smooth muscle encircles those airways. When something irritates the lungs, the muscle spasms, narrowing air passages to leave patients gasping. Swelling further closes off their air. Repeated attacks thicken muscle so airways can become habitually narrowed, and the muscle becomes even more sensitive to asthma triggers.
Bronchial thermoplasty promises to get rid of half of that thickened muscle, in hopes that the airways will behave more normally.
Doctors sedate patients and thread a lighted catheter through the nose or throat and into the branch-like airways that fill the lungs. A wire basket on the tip is inflated to touch the airway walls, and radiofrequency waves are beamed through those wires.
Simoff compares it to a microwave oven, which cooks meat without scorching the outer skin like a grill would. The RF waves work similarly: They appear to beam through the airway's thin lining without scarring it, while heating smooth muscle underneath to 149 degrees - hot enough that some muscle tissue basically disintegrates.
It takes three outpatient treatments, a half-hour each, to inch the RF device throughout the lungs, reaching main airways.