DVT: Removing Deadly Filters

FRESNO, Calif.

Doctors used to implant permanent filters to prevent the clot 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 one woman.

Susan Karnstedt and her family have always lived active lives.

"We're big hikers, bikers, waterskiing, wake-boarding. We love all the snow sports!" Susan Karnstedt told Ivanhoe. But all those adventures stopped when Susan suffered severe abdominal pain.

"I would wake up, throbbing pain, would take a painkiller, would sleep with a heating pad," Susan said.

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," Susan said. "I was like, 'oh my god.'" The device was a filter that doctors inserted to catch a blood clot before it traveled to Susan'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," William T. Kuo, M.D., with Stanford University Medical Center said.

Susan'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.

"They thought trying to remove it would kill me. I would bleed out on the table," Susan said.

Then, she found doctor William Kuo -- who pioneered a new procedure that uses lasertechnology.

"Before we conducted our research in this area, there was no option for treating patients," Dr. Kuo said.

Doctor Kuo made a four-millimeter incision in Susan'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 Susan's life.

"The pain was gone," Susan said. "I felt great."

With no filter, she's active again and enjoying the outdoors. Doctor Kuo says since Susan's successful procedure, dozens of patients around the country have contacted him and been treated.

If this story or any other Ivanhoe story has impacted your life or prompted you or someone you know to seek or change treatments, please let us know by contacting Marsha Hitchcock at mhitchcock@ivanhoe.com

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