(Philadelphia, PA) - Deep vein thrombosis (DVT) is a common medical condition in which blood clots develop in the deep veins of the body, often in the legs, thigh or pelvis. These clots can break loose and travel to the lungs and can cause a life-threatening pulmonary embolism (PE). Proximal DVT, which refers to a clot in the thigh or pelvis, has been shown to be associated with a higher risk for post-thrombotic syndrome (PTS), a painful condition characterized by swelling, redness and sores on the legs.
In an effort to reduce the high incidence of PTS seen in patients treated with a blood thinner alone, many physicians now utilize catheter-directed thrombolysis (CDT), which is a fluoroscopically guided, minimally invasive procedure in which an infusion catheter is used to deliver clot-busting drugs directly into the clot. CDT can potentially reestablish blood flow through a newly blocked vein.
Some physicians opt to also implant an inferior vena cava filter (IVCF) at the time of CDT in an attempt to prevent clots from breaking loose and migrating to the lungs during the procedure, causing a pulmonary embolism. IVCFs are small, basket-like devices made of wire that are inserted into the inferior vena cava, a large vein that returns blood from the lower body to the heart and lungs, to capture the blood clots and prevent them from reaching the lungs.
However, the true benefit of IVCF placement at the time of CDT is unclear. A research team led by Riyaz Bashir, MD, FACC, RVT, Professor of Medicine at the Lewis Katz School of Medicine at Temple University (LKSOM), and Director of Vascular and Endovascular Medicine at Temple University Hospital (TUH), sought to address this question by examining nationwide utilization rates of IVCFs in patients undergoing CDT to assess contemporary trends and comparative outcomes to patients who do not undergo IVCF placement. The team's findings were published online July 16th and in the July 23rd issue of the journal JACC: Cardiovascular Interventions.
"Limited data exists on the effectiveness of IVCF use in patients undergoing CDT for the treatment of proximal DVT," said Dr. Bashir. "This study is noteworthy because it is the first to evaluate national trends and comparative outcomes related to this practice."
The research team used the National Inpatient Sample database to identify all patients in the U.S. with DVT that underwent CDT (with and without IVCF placement) in the United States between January 2005 and December 2013.
Among the team's findings:
- There was a steady increase in CDT use in patients diagnosed with DVT throughout the study period: from 2.3% in 2005 to 8.1% in 2013.
- The use of IVCFs in patients undergoing CDT for DVT remained steady at about 30% throughout the study period.
- IVCF use in patients undergoing CDT for DVT was not associated with any significant in-hospital mortality decrease compared to patients who did not receive an IVCF.
- IVCF use in patients undergoing CDT for DVT was associated with an increase in procedure-related hematoma formation (3.4% vs. 2.1%), in-hospital costs ($104,049 vs. $92,881) and length of stay (7.3 days vs. 6.9 days) compared to patients who did not receive an IVCF.
"On the basis of these results, we believe that IVCFs should not be routinely placed in patients undergoing CDT," added Dr. Bashir. "Additional well-designed, randomized control trials are encouraged to elucidate the implications of IVCF placement in patients undergoing CDT."
Other researchers involved in the study include Vladimir Lakhter and Vikas Aggarwal in the Department of Cardiovascular Diseases, TUH; Huaqing Zhao in the Department of Clinical Sciences at TUH; Ravi Dhanisetty in the Department of Vascular Surgery at TUH; Othman S. Akhtar in the Department of Internal Medicine at the University of Buffalo, Buffalo, NY; Chad J. Zack in the Department of Cardiovascular Diseases at Duke University Medical Center, Durham, NC; Hafiz Hussain in the Department of Cardiovascular Diseases at New York Presbyterian Queens Hospital, Queens, NY; Estefania Oliveros in the Department of Cardiovascular Diseases at Rush University Medical Center, Chicago, IL; Yevgeniy Brailovsky in the Department of Cardiovascular Diseases at Loyola University Medical Center, Maywood, IL; Resmi A. Charalel in the Department of Interventional Radiology at Washington University School of Medicine, St. Louis, MO; and Matthew Zhao in the Department of Chemistry at New York University, New York, NY.
Editor's Note: Dr. Bashir is a co-founder and has equity interest in Thrombolex, Inc., a medical device company which is developing the treatment of large vessel thrombosis.
About Temple Health
Temple University Health System (TUHS) is a $2.1 billion academic health system dedicated to providing access to quality patient care and supporting excellence in medical education and research. The Health System consists of Temple University Hospital (TUH), ranked among the "Best Hospitals" in the region by U.S. News & World Report; TUH-Episcopal Campus; TUH-Northeastern Campus; Fox Chase Cancer Center, an NCI-designated comprehensive cancer center; Jeanes Hospital, a community-based hospital offering medical, surgical and emergency services; Temple Transport Team, a ground and air-ambulance company; and Temple Physicians, Inc., a network of community-based specialty and primary-care physician practices. TUHS is affiliated with the Lewis Katz School of Medicine at Temple University, and Temple University Physicians, which is Temple Health's physician practice plan comprised of more than 500 full-time and part-time academic physicians in 20 clinical departments.
The Lewis Katz School of Medicine (LKSOM), established in 1901, is one of the nation's leading medical schools. Each year, the School of Medicine educates approximately 840 medical students and 140 graduate students. Based on its level of funding from the National Institutes of Health, the Katz School of Medicine is the second-highest ranked medical school in Philadelphia and the third-highest in the Commonwealth of Pennsylvania. According to U.S. News & World Report, LKSOM is among the top 10 most applied-to medical schools in the nation.
Temple Health refers to the health, education and research activities carried out by the affiliates of Temple University Health System (TUHS) and by the Katz School of Medicine. TUHS neither provides nor controls the provision of health care. All health care is provided by its member organizations or independent health care providers affiliated with TUHS member organizations. Each TUHS member organization is owned and operated pursuant to its governing documents.