Report: Deciding about Vascular Laboratory Tests

07/26/2013
Photo: Doctor

A new report provides detailed criteria to help clinicians optimize the appro-
priate use of certain noninvasive vascular tests; © panthermedia.net/
Melinda Nagy

A new report provides detailed criteria to help clinicians optimize the appropriate use of certain noninvasive vascular tests when caring for patients with known or suspected disorders of the venous (veins) system.

Also included are first-time recommendations for when and how to use these tests to plan for or evaluate dialysis access placement. The report is issued by the American College of Cardiology (ACC) and developed in collaboration with 10 other leading professional societies. "Vascular lab testing is central to the care of patients with most peripheral vascular disorders, but appropriate use criteria for these [technologies] have lagged behind those for cardiac testing," said Heather Gornik, cardiologist and vascular medicine specialist at the Cleveland Clinic. "With this report, we now have multidisciplinary criteria upon which we can start maximizing the quality and appropriateness of what we do in the vascular lab every day."

Vascular testing is often used to help evaluate possible venous thromboembolism, which is the third most common cardiovascular disease, after coronary disease and stroke, and includes deep vein thrombosis (DVT) as well as pulmonary embolism (PE). These conditions can be fatal and result in hospitalizations and long-term complications. Therefore, identifying the best methods for detecting clots in the veins early on can be lifesaving, Gornik said. "But we must know that we are ordering the right test for the right reasons," she added.

The new report offers comprehensive, at-a-glance guidance on when – and when not – to refer patients for vascular laboratory testing (for example, duplex ultrasound and physiological testing using blood flow sensors) to help detect such problems as venous insufficiency, varicose veins, blood clots in the veins the leg, arm or abdomen, and pulmonary embolism. These criteria are a follow-up to the group's previously issued guidance evaluating the use of the vascular laboratory for diagnosing and monitoring the arterial side of the circulatory system.

Overall, vascular studies were deemed appropriate when clinical signs and symptoms are the main reason for testing. For example, if a patient has swelling, discoloration or pain in one leg, experts agree that it is reasonable to order a duplex ultrasound evaluation of the legs to determine whether there might be a DVT or clot. In contrast, it is rarely appropriate to use these tests to screen for DVT in patients without symptoms – even in those who are more prone to clotting or who have had an extended intensive care unit or hospital stay, recent (major) orthopedic surgery or a positive D-dimer blood test.

"Vascular ultrasound is now the best, most accurate test we have for diagnosing DVT and it has clear advantages, including its low risk to the patient with no exposure to radiation or contrast dye and the fact that it is less expensive relative to other tests," Gornik said. "But a lot of screening ultrasounds are done indiscriminately for asymptomatic patients, and we found there is little evidence to support that practice."

"There is also growing need for comparative and cost-effectiveness research of vascular laboratory testing in the care and diagnosis of patients with deep vein thrombosis and pulmonary embolism," she said. "There are also a number of controversial areas that have not yet been fully explored, which we have outlined." One example is whether patients with blood clots in their calf should be treated with blood thinning medication versus duplex ultrasound surveillance.

MEDICA.de; Source: American College of Cardiology