Clinical Trial: Breakthrough Technology Used for Blood Clots in Veins

A Case of Deep Vein Thrombosis

Brittany Foor, 22, — a stay-at-home mother of three — is used to being on her feet.  She enjoys chasing after her toddlers and tending to her newborn baby, Lyla’s needs. But a recent medical emergency temporarily stopped Foor from her daily motherly tasks.

“At first, I noticed a lot of pressure in my lower back, and I thought it was associated with my recent pregnancy,” Foor said, “But then a shooting pain began to spread down my left leg every time I tried to take a step. When it turned purple and hurt too much to walk, I decided it was time to visit the ER.”

Foor had been experiencing excruciating pain for nearly a week before she visited ProMedica Bixby Hospital in Adrian, Mich. in January. The ultrasound results indicated that Foor had a life-threatening blood clot in her left leg, which extended up into her abdomen. She was diagnosed with Deep Vein Thrombosis (DVT), which if not caught in time and treated, can become deadly. Symptoms include swelling of the leg, pain that can prevent the patient from moving normally and discoloration.

Foor was prescribed blood thinners, which, along with compression stockings and advice to keep the leg elevated, has been the recommended treatment for patients experiencing blood clots in their veins.

Jobst Vascular Institute Clinical Study

Foor was immediately put in contact with Anthony J. Comerota, MD, FACS, director of Jobst Vascular Institute at ProMedica Toledo Hospital. After the extensive DVT of her leg was dissolved, Foor qualified to participate in a clinical trial of a new venous stent, which is being studied for subsequent approval by the United States Food and Drug Administration. Currently there are no stents approved in the United States for use in the venous system.

“Veins differ from arteries,” said Dr. Comerota. “While arteries are muscular and under high pressure as they deliver blood throughout the body, veins are low pressure thin walled vessels that return blood to the heart. The stent characteristics required by obstructed veins are different from those required by an artery.”

Foor is the third patient in the country to participate in the Cook Medical VIVO clinical research study, helping researchers test out the effectiveness of the Zilver® VenaTM Venous Self-Expanding Stent. And ProMedica Toledo Hospital is the second facility in the nation to offer the stent on a clinical trial basis.

“Because it’s a clinical trial, we follow a well designed protocol,” Dr. Comerota said. “Patients are treated with appropriate medication, receive careful follow up care and have repeat imaging.”

The stent itself is a metal mesh cylinder that props open the vein. It is threaded up the leg through a small catheter that enters a vein behind the knee. When the stent reaches the diseased section of vein, it is then released, where it stretches the vein to a normal diameter to return blood to the heart. Like a metal Slinky®, it moves and bends with the patient’s body without closing. The stent will remain inside the patient’s vein for life.


The VIVO clinical research study is groundbreaking. Its results could potentially improve the lives of thousands of people. Though Foor is only the third patient to be entered into this clinical trial with the venous stent, Dr. Comerota is optimistic that approximately 200 patients will enroll in the study across the U.S. He said that it will take approximately 2½-3 years to complete the study. Once the research is complete, Dr. Comerota plans to take his findings to Washington to seek the FDA’s approval.

“So far, we’ve been able to restore veins to their normal diameter,” he said. “The goal is to improve the patient’s quality of life and return them to their normal daily activity.”

As for Foor, just hours after the procedure she was already starting to find relief. “My leg is back to normal, like nothing even happened,” she said. “I’m back to being a mom again.”

To learn more about the Jobst Vascular Institute at ProMedica Toledo Hospital, please visit For more information about participating in the Cook Medical VIVO clinical research study, please contact Dr. Comerota at 419-291-2088.

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