LEXINGTON, Ky. --Thirty-two-year-old Frank Cienniwa went to the emergency room thinking he was having a heart attack.

He left with a different diagnosis -- acid reflux.

"It's like a constant severe heartburn to the degree that even bland foods like toast and oatmeal cause discomfort," Cienniwa said as he recalled the incident that gave him quite a scare five years ago.

A new experimental treatment for the condition, formally known as gastroesophageal reflux disease (GERD), performed as part of a clinical trial at the University of Kentucky Medical Center, may provide relief to Cienniwa and millions of Americans who struggle with the problem.

The treatment involves a simple endoscopic procedure in which four tiny prostheses are implanted into the wall of the esophagus. The devices -- which look like No. 2 pencil leads -- expand to keep acid from moving up into the esophagus while allowing food to pass into the stomach.

"I suspect this is going to be a major advance in fighting reflux disease," said Dr. Nicholas Nickl, professor of internal medicine in the gastroenterology department of the University of Kentucky College of Medicine.

"New endoscopy treatments introduced over the past two years or so have not been widely accepted because they are either technically very complex or can cause permanent damage to the esophagus."

Malfunctioning muscle

More than 60 million American adults experience reflux and heartburn at least once a month, and about 21 million are estimated to have acid reflux disease.

Those with the disease commonly complain of serious, continual heartburn before being diagnosed. It occurs when a muscle in the lower esophagus does not function correctly, allowing digestive acids to move upstream.

Many with the disease must take medication daily for the rest of their lives or undergo invasive surgical procedures to gain relief from the pain. It also can cause such complications as ulcers or esophageal cancer.

The new Gatekeeper Reflux Repair System is being tested at fewer than a dozen sites worldwide. So far, the medical center is the third site in the United States to participate in the trial.

The prostheses are made of a flexible material called hydrogel, which is used in making contact lenses. They are inserted into the walls of the esophagus and within 24 hours swell into tiny pillows that act as barriers to the rising acid. The prostheses are soft enough, however, that food is not blocked as it travels down into the stomach.

"In a similar European trial, none of the patients reported any problems with food passing into the stomach," Nickl said. "They simply add a little muscle at the bottom of the esophagus to prevent the reflux."

'An excellent concept'

Dr. Charles Filipi, professor of surgery at the Creighton University School of Medicine in Omaha, Neb., said minimally invasive procedures involving laparoscopy and endoscopy are becoming more accepted in treating reflux.

"I think this is an excellent concept," Filipi said of the clinical trial. "There will always be a slight risk when you are putting prosthetic material into the esophagus, but it sounds like the problems seen with this new treatment have been minimal."

He said that as long as the prostheses stay in place and don't disengage from coughing or regurgitating, "it sounds like it has potential. More widespread testing and trials will be the only way to know for sure."

Dr. Sharni Rakhra, a gastroenterologist at the Lexington Clinic, also praised the idea, but wondered if there might be some long-term problems, such as getting the food past the device if there is irritation or swelling of the esophagus.