Adults with severe, long-term asthma that is not controlled by medication might have cause to breathe easier. On Tuesday, the U.S. Food and Drug Administration approved a device that opens up the lungs by reducing excess muscle tissue.

The device, called Alair Bronchial Thermoplasty System, delivers radiofrequency energy to airways in the lungs to mildly heat and reduce excess smooth muscle tissue that can constrict breathing in chronic asthma sufferers.

With the excess muscle gone, air then flows through with less difficulty, and the patient breathes easier, according to the FDA.

"The approval of the Alair system provides adult patients suffering from severe and persistent asthma with an additional treatment option for a disease that is often difficult to manage," Dr. Jeffrey Shuren, director of the FDA's Center for Devices and Radiological Health, said in a statement.

Around 22 million Americans suffer from asthma, according to the National Institutes of Health. In this disease, the muscle tissue in the airways of the lung can become inflamed, blocking the natural passage of air and making it tough for patients to breathe. The societal effects of the condition are profound: A recent Centers for Disease Control and Prevention report found that employees missed around 10 million work days, and children around 13 million school days, because of the condition.

HOW THERMOPLASTY WORKS

The new treatment, called bronchial thermoplasty by its developer, Asthmatx, is done over the course of a few weeks in three outpatient procedures. The patient is sedated, and then a tube called a bronchoscope is inserted through the mouth. The Alair wand is then snaked through the bronchoscope and brought down into the airways. There, it releases wires to come into contact with the lung tissue, where the thermal energy heat-shrinks it. Patients are given a steroid drug before and after the procedure.

Asthmatx says they've run four clinical studies on the product. The FDA's approval is based on one of the trials, called the AIR 2 trial, which involved 297 patients. The results appeared originally in the American Journal of Respiratory and Critical Care Medicine in January.

In the trial, the Sunnyvale, Calif-based Asthmatx claims that, compared with control subjects, patients who underwent the Alair treatment enjoyed improved symptoms and fewer hospital visits.

According to the company, treated patients experienced an 84 percent reduction in emergency room visits, a 32 percent reduction in asthma attacks, a 73 percent reduction in hospitalizations and a 66 percent reduction in days lost from school, work or other daily activities.

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