Bariatric Embolization is a Potential Weapon Against Morbid Obesity
Wednesday, Dec. 02, 2015
Bariatric embolization shows "tremendous" promise as a safe, less-invasive weight-loss technique for morbidly obese patients, according to preliminary results of a pilot study presented by Mubin I. Syed, M.D.
In an RSNA press conference on Tuesday, Dr. Syed said the study could pave the way to a minimally invasive treatment for obesity that could be performed as an outpatient procedure.
"The patients weren't even in a hospital. It's that safe," Dr. Syed said. "And they leave with a little Band-Aid."
Of the four patients who have undergone the procedure, one lost 48 pounds in a year, which was almost half of her excess body weight, Dr. Syed said. "That is equal to results from bariatric surgery, so that's tremendous," he said.
Another patient, who is diabetic, lost 26 pounds in three months, Dr. Syed said. In addition, the patient's hemoglobin A1C levels dropped to normal.
Before the study, Dr. Syed confirmed that the FDA authorized a diabetic patient to undergo this procedure for the first time because of the link between morbid obesity and diabetes. "It has major clinical implications from a public health perspective because so many obese patients are diabetic," he said.
Dr. Syed conducted the Phase 1 trial through an Investigational Device Exemption (IDE) from the FDA. The FDA approved the pilot study—the Gastric Artery Embolization Trial for Lessening Appetite Nonsurgically (GET LEAN)—for five morbidly obese patients with a body mass index of 40 or higher, who had failed previous attempts at weight loss through diet, exercise and behavior modification. He is still seeking his fifth patient and expects to be allowed to increase the trial size.
Although only two of the four patients showed significant weight loss, Dr. Syed believes the procedure is promising because the two patients who did not lose weight withheld parts of their medical history that would have excluded them from the study. Dr. Syed said the experience taught him how to refine his screening procedure.
More conclusively, "we can say that so far we have not had any adverse effects," Dr. Syed said. Some patients experience nausea and stomach pain, but no symptoms required hospitalization. Also, superficial ulcerations occur in the embolization area but they heal within 30 days and are an expected part of the procedure, Dr. Syed said.
Embolization for Obesity a New Procedure
Interventional radiologists have performed gastric artery embolization for decades as a way to stop bleeding in emergency situations, but the idea of performing the procedure as a means of treating obesity is new.
The embolization technique suppresses the production of ghrelin, which is a hormone that stimulates appetite, by limiting blood flow to the area. This technique is less invasive and less traumatic than laparoscopic sleeve gastrectomy, Dr. Syed said.
As opposed to surgically removing part of the stomach, the embolization technique only requires access via the radial artery. "That's a very safe access site even in a very obese patient," he said.
Dr. Syed said he accessed the left gastric artery through the arm instead of the groin because the patients' fatty tissue makes those arteries difficult to locate in the first place and to later put pressure on to stop any bleeding.
The pilot study used Beadblock 300-500 micron particles for the embolization. Dr. Syed said smaller beads, which were used in previous studies on animals, might be more effective but the sizes used in this study were as small as the FDA would approve.
The trial did not show significant reduction in ghrelin levels, but Dr. Syed did not draw any conclusions on that data because of the small sample size.