Venous duplex ultrasound is rarely appropriate as a screening tool for upper or lower extremity deep vein thrombosis in the absence of pain or swelling, according to new appropriate use criteria for noninvasive vascular laboratory testing issued by the American College of Cardiology.
The clinical scenarios involving venous duplex ultrasound for DVT screening that were deemed rarely appropriate – such as screening in those with a prolonged ICU stay and those with high DVT risk – represent just a few of the 116 scenarios included in the report, which was developed in collaboration with 10 other leading professional societies to promote the most effective and most efficient use of peripheral vascular ultrasound and physiological testing in clinical practice.
The report, published online on July 19 in the Journal of the American College of Cardiology, is the second in a two-part series evaluating noninvasive testing for peripheral vascular disorders. Part I, published last year (J. Am. Coll. Cardiol. 2012;60:242-76), addressed peripheral arterial disorders, and Part II (J. Am. Coll. Cardiol. 2013 July 19 [doi:10.1016/j.jacc.2013.05.001]) addresses venous disease and evaluation of hemodialysis access, according to Dr. Heather Gornik, chair of the Part II writing committee.
"Vascular laboratory tests really play a central role in evaluating patients with peripheral vascular disorders. They are noninvasive, they have good accuracy data, and they don’t require radiation or dye. But we want to make sure the right tests are being ordered for the right reasons," Dr. Gornik, a cardiologist and vascular medicine specialist at the Cleveland Clinic, said in an interview.
Because these tests are low risk and easily accessible, there is concern that they are sometimes used excessively, she explained – specifically mentioning the use of duplex ultrasound for DVT screening as a commonly overused procedure.
"There is very little evidence, if any, to support broad screening for blood clots in someone who has no symptoms," she said.
The goal of the ACC Foundation Appropriate Use Criteria Task Force responsible for developing the criteria was to help clinicians minimize unnecessary testing, and maximize the most effective and efficient testing, she added.
Each of the clinical scenarios that were developed by the writing committee were rated by a technical panel as to whether they represent an "appropriate use," or whether they are "maybe appropriate" or "rarely appropriate."
The various scenarios are listed, along with their rating, in eight "at-a-glance" tables that address the following more general categories: venous duplex of the upper extremities for assessing patency and thrombosis; venous duplex of the lower extremities for assessing patency and thrombosis; duplex evaluation for venous incompetency; venous physiological testing with provocative maneuvers to assess for patency and/or incompetency; duplex of the inferior vena cava and iliac veins for patency and thrombosis; duplex of the hepatoportal system for patency, thrombosis, and flow direction; duplex of the renal vein for patency and thrombosis; and preoperative planning and postoperative assessment of a vascular access site.
Considering venous duplex ultrasound in a patient with acute unilateral limb swelling? Table 1 lists this as an appropriate use. How about duplex evaluation for venous incompetency in a patient with asymptomatic varicose veins? Table 3 says this may be appropriate, but notes that it is rarely appropriate in a patient with spider veins.
The report also covers indications for vascular testing prior to or after placement of hemodialysis access, because "evaluation of the superficial, deep, and central veins of the upper extremity constitutes a large component of these examinations," the report states.
In general, vascular studies were deemed appropriate in the presence of clinical signs and symptoms. The report also shows that the vascular laboratory plays a central role in the evaluation of patients with chronic venous insufficiency, and that preoperative vascular testing for preparing a dialysis access site is appropriate within three months of the procedure – but not for general surveillance of a functional dialysis fistula or graft in the absence of an indication of a problem, such as a palpable mass or swelling in the arm.
The report is not intended to be comprehensive, but rather is an attempt to address common and important clinical scenarios encountered in the patient with manifestations of peripheral vascular disease, the authors noted.
"The beauty of this report is that it spans many disciplines," Dr. Gornik said, noting that numerous parties have an interest in peripheral vascular disease, and that many specialties order vascular laboratory tests.
A number of them were represented in the development of these appropriate use criteria. Collaborating organizations included the American College of Radiology, the American Institute of Ultrasound in Medicine, the American Society of Echocardiography, the American Society of Nephrology, Intersocietal Accreditation Commission, Society for Cardiovascular Angiography and Interventions, the Society of Cardiovascular Computed Tomography, the Society for Interventional Radiology, the Society for Vascular Medicine, and the Society for Vascular Surgery.