Heart & Vascular Institute Physician eNewsletter - Fall 2012
Past Medical History
Image 1: Preoperative scout image
of IVC Filter for removal
Jane*, 68, needed knee surgery in the spring of 2012, but she was considered a high-risk patient for this procedure because she previously suffered from a pulmonary embolism caused by blood clots in her legs, known as deep vein thrombosis (DVT). While Jane was taking anti-coagulants to prevent another episode, doctors determined that an inferior vena cava (IVC) filter should be placed in her abdomen prior to knee surgery. That way, if DVT occurred following the knee surgery, the IVC filter would stop another pulmonary embolism from occurring.
An IVC filter is a device that fits in the inferior vena cava, the major vein connecting the legs to the heart, and captures emboli before they can reach the pulmonary arteries. These devices are placed percutaneously via the groin or neck to the area in the abdomen just below the junction of the inferior vena cava vein and renal vein. Removable filters like the one Jane needed are placed during an acute illness or prior to surgery in patients with DVT or PE who can’t be anticoagulated because of the surgery.
Unfortunately, many removable IVC filters are not removed from patients, and these medical devices can pose a risk of breaking, penetrating the vein wall or migrating up the vessel. In rare cases, IVC filters have migrated to heart chambers.
In Jane’s case, her doctors in Marietta, Ohio, were concerned about removing the IVC filter following a successful knee surgery because they identified that the filter had tilted and the apex of the device had become imbedded in the wall of the inferior vena cava. They could not capture the top of the IVC filter to remove it and were considering an open surgical procedure for removal before calling Cleveland Clinic.
Hospital Course at Cleveland Clinic
Jane was scheduled into the IVC Filter Retrieval Clinic where Mark Sands, MD, Vice Chair of Clinical Operations and Quality and Section Head of Interventional Radiology at the Imaging Institute, reviewed the risks of removal with her. Jane was not feeling any symptoms of the imbedded filter—though she might have experienced lower back or abdominal pain. And, while there are risks with any procedure, the minimally invasive process of removing an IVC filter proved a much safer option than performing an open procedure.
Dr. Sands and Gordan McLennan, MD, of Diagnostic Radiology, have been involved in IVC filter retrievals since the original clinical trials last decade. During the IVC filter removal procedure, Dr. McLennan used ultrasound to enter through a small quarter-inch incision into the internal jugular vein to gain access and remove the IVC filter. These procedures generally take approximately 20 minutes to one hour, depending on the complexity. Jane’s procedure took 20 minutes with one hour of post-procedure recovery.
Jane went home without the IVC filter in her body. It is not certain that the device would have harmed Jane if it was left in the inferior vena cava, but the doctors’ assessment determined that the filter was providing poor protection in its current location. They agreed with her referring doctors’ preference to remove the filter. While there was no immediate danger to the patient, there was a possibility that the filter could fracture or penetrate the blood vessel wall over time.
Image 2: Interoperative image
of captured IVC Filter being removed
“IVC filters can become obstructive, and patients that have filters have an increased risk of blood clots in their legs,” says John Bartholomew, MD, Section Head of Vascular Medicine, Medical Director of the Pharmacy run Anticoagulation Clinic, and co-leader of Cleveland Clinic’s IVC Filter Retrieval Clinic. The IVC Clinic is also led by Mark Sands, MD and Gordon McLennan, MD with coordination efforts by Shelly Brancatelli, RRA, RPA, RT(R), CV.
The IVC Filter Retrieval Clinic was created to address the FDA’s concerns after receiving more than 900 reports of adverse events with IVC filters. “We are making sure that if we put an IVC filter in a patient that we take it out if it should be taken out,” Dr. Bartholomew says, noting that every filter placed at Cleveland Clinic will be listed in a registry so the team can follow up with patients and determine whether the device should be removed.
This is determined on a case-by-case basis. Not all IVC filters must be removed. For some patients, the IVC filter may best remain in place to extend the benefits of its presence. That’s why patients need to be thoroughly evaluated to determine the best course of action for their particular circumstance. Some may require the use of blood thinning medications (anti-coagulation). This can be determined at the clinic visit.
Cleveland Clinic is working toward achieving the FDA’s goal to remove as many of these optionally retrievable IVC filters as possible, and the IVC Filter Retrieval Clinic team is currently available to patients for consultations. “Not everyone will get a blood clot from an IVC filter that is not removed, and most filters will not migrate, fracture or cause pain. But nevertheless, we want to keep track of patients who have IVC filters and follow up accordingly,” Dr. Bartholomew says.
*Patient's name has been changed.