Medtronic’s new Bravo™ pH monitoring system represents a significant advancement over traditional methods of diagnosing and monitoring gastrointestinal reflux disease (GERD). The conventional technique involves insertion of a nasal catheter to monitor the esophagus’ acidity, but is uncomfortable, inhibiting, and only tolerable for approximately twenty-four hours. On the contrary, the Bravo system involves the endoscopic insertion of a small capsule, which can remain in place for forty-eight hours or longer with no interference in daily life. Dr. John Pandolfino, who coordinated one study evaluating the new device, noted that the unobtrusive and more comfortable aspects of the Bravo method allow for more normal behavior and longer recording times, thereby increasing accuracy in GERD diagnosis.GERD affects an estimated 21 million Americans, and until recently their only option for esophageal pH monitoring was via nasal catheter. Unfortunately, the obtrusive nature of this device has been found to prevent many individuals from pursuing their normal activities, thus potentially generating false readings. Patients are reportedly more reluctant to engage in social activities, and alter their usual patterns of work, diet, exercise, showering, and sleep. Moreover, the 24 hour limitation on the device means that sporadic episodes of reflux may not be recorded.
According to Medtronic’s literature and several studies to date, the Bravo system avoids these problems and thus significantly improves accuracy of GERD diagnosis. Medtronic has developed a small capsule, approximately the size of a gel cap, which is inserted endoscopically into the patient’s esophagus and attached to the esophageal wall. This capsule monitors esophageal pH, and transmits data via radio frequency to a small receiver worn by the patient. At the end of 48 hours, or other set monitoring window, data from this receiver is downloaded into a computer and analyzed via Medtronic’s Polygram Net pH software. Between seven and ten days after the initial insertion, the capsule spontaneously detaches and passes through the digestive system.
To date, several studies have confirmed the advantages of this new method of pH monitoring. One study, directed by Dr. Edward Lin of the Emory University School of Medicine Endosurgery Unit, involved 245 patients over a period of two years. His group found that 48 hour monitoring using the Bravo system significantly enhanced the ability to identify abnormalities in comparison to mere 24 hour monitoring. The additional 24 hours yielded an additional 10% of abnormal pH readings. The system was also found to record longer and more frequent reflux episodes. Yet another study, coordinated by Dr. Pandolfino, monitored 85 patients, approximately half of whom had been diagnosed with symptoms of GERD. Significantly, 12 of these individuals had normal esophageal pH readings on one day, but recorded abnormal levels of acidity on the other. Three patients did require removal of the capsule endoscopically; however overall patient comfort and satisfaction was greatly improved over traditional methods. Additional studies also indicated that this new technology identifies a higher number of reflux episodes than traditional methods.
The Bravo system has been approved by the Food and Drug Administration (FDA), and clearly represents significant advancements in pH monitoring techniques. It has been commercially available since May 2002, and won Popular Science’s “Best of What’s New Award” for 2002.
