“I would love to see more vascular surgeon-led sites participate and more physicians participate more fully”
Vascular surgeons have the opportunity to help create standards re, track patients who need inferior vena cava filters removed and, ultimately, set guidelines for the treatment of thromboembolism through participating in a national study on the real-world use of the filters.
Dr. David Gillespie is co-principal investigator for PRESERVE: Predicting the Safety and Effectiveness of Inferior Vena Cava Filters. Dr. Matthew S. Johnson, FSIR, is co-principal investigator from the Society for Interventional Radiology. The study, sponsored by the IVC Filter Study Group Foundation, is a collaboration between SVS, SIR, FDA and filter manufacturers.
Many SVS members are site principal investigators at the planned 60 sites who will enroll patients in PRESERVE, which focuses on filters from six manufacturers. Investigators will follow 1,800 patients, 300 patients for each of the six filters involved.
Currently, the trial has enrolled 356 patients at 32 sites, 19 of them led by vascular surgeons. “I would love to see more vascular surgeon-led sites participate and more physicians participate more fully,” said Dr. Gillespie, urging his fellow SVS members to “take ownership of the treatment of DVT and PE with filters,” and participate. “We certainly do with treatment of DVT using thrombolysis and venous stenting,” he said.
Members will benefit through the specialty setting standards of care and for setting guidelines for the treatment of thromboembolism, Dr. Gillespie said. Just as importantly, data from PRESERVE will “highlight more specifically the complication rate of all these filters and compare them. Then members can make their own decision about which filter to use.”
The PRESERVE study, he said, will “basically populate a dataset that could be used for research and publication for years to come.”
PRESERVE has its roots in the 1990s and 2000s, with the rapidly increasing use of IVC filter implantations to prevent pulmonary embolism death. This is especially true in the case of IVC insertion in trauma patients who had never had PE or deep vein thrombosis. “Trauma patients are considered at very high risk of PE and DVT and have a perceived contraindication to anti-coagulation,” said Dr. Gillespie.
It is estimated that blood clots affect between 350,000 and 600,000 people each year in the United States, with 100,000 to 180,000 dying each year of pulmonary embolism. Approximately 250,000 patients a year receive the IVC filters.
A significant problem, however, is that for a variety of reasons, filters put in under the assumption they would be removed, weren’t. Trauma patients most likely receive emergency treatment and may not follow up with their physicians for filter removal. With that lack of follow-through on the part of physicians, plus an increasing rate of implantations, the number of patients experiencing filter complications increased, Dr. Gillespie said.
“Even if the rate is low, with an exponential number being implanted, that number becomes a real number of patients,” Dr. Gillespie said.
Because of the number of patients experiencing complications from IVC filters, the FDA mandated that all manufacturers of IVC filters complete further studies to demonstrate their safety and efficacy. As an alternative, the SVS and SIR collaborated to create the investigator-initiated study, PRESERVE. “It’s a monumental study,” said Dr. Gillespie.
Dr. Clifford Sales, who manages a large private practice vascular surgery group in New Jersey, is lead vascular surgeon of a site that has been enrolling patients briskly. “We are in a center that is recognized for its neurological care, so we have a great deal of candidates for the procedure,” he said.
He urged fellow SVS members either to lead enrollment at their institutions or to be involved in enrolling patients, partially because of the important and useful data PRESERVE will generate.
“There’s very little in the literature about the long-term placement of the filters,” Dr. Sales said. “And the study is a good way to monitor and follow up on retrievals. That is important information that we need to understand from this study.”
To learn more about PRESERVE, visit www.preservetrial.com