A disease that affects about two million Americans

April 4, 2011 3:12:40 PM PDT
It was supposed to save her life, but a tiny filter nearly killed Susan Karnstedt.

Deep vein-thrombosis (DVT) affects about two million Americans each year. It happens when a blood clot forms in the leg and blocks circulation.

Doctors used to implant permanent filters to prevent bloods clots from traveling to the lungs. But now, many believe some of those devices did more harm than good.

Removing a once-permanent filter was a risky but necessary operation for Karnstedt. "It was like a fork. It was a fork protruding into my small intestine," said Karnstedt.

Karnstedt and her family have always lived active lives. "We're big hikers, bikers, waterskiing, wake-boarding. We love all the snow sports," said Karnstedt.

But all those adventures stopped when she from suffered severe abdominal pain. "I would wake up with throbbing pain, would take a painkiller, and would sleep with a heating pad," she added.

For months, she thought it was her diet that was making her sick. But a CT-Scan showed something else. A device she had implanted 18 years ago to treat a clotting condition was impaling one of her organs.

"There were three of the prongs clearly perforating into my small intestine. I was like, 'Oh my God,' you know," said Karnstedt. The device was a filter that doctors inserted to catch a blood clot before it traveled to Karnstedt's lungs. Back then, they thought it was helpful. Now, it's proven to be dangerous.

"We're starting to realize that the longer a device is left implanted, the more chance there is of a complication occurring," said Dr William T. Kuo, MD Director, Stanford IVC Filter Clinic Stanford University Medical Center.

Karnstedt's filter had formed scar tissue around her vein. Doctors told her leaving it in would cause more damage, but removing the permanent device was too risky.

"The thought was trying to remove it would kill me. I would bleed out on the table," said Karnstedt.

Then, she found Dr.Kuo, who pioneered a new procedure that uses laser technology. "Before we conducted our research in this area, there was no option for treating patients," said Dr. Kuo.

Dr. Kuo made a four-millimeter incision in Karnstedt's neck and carefully guided a catheter down to her vena cava. He used a special laser to separate the scar tissue and then removed the filter without any damage to her vessels.

What was supposed to be a life-threatening surgery turned into a surgery that saved Karnstedt's life. "The pain was gone. I felt great," said Karnstedt.

With no filter, she's active again and enjoying the outdoors. Since Karnstedt's successful procedure, dozens of patients around the country have Dr. Kuo and been treated.
For more information, please visit: www.preventdvt.org