Appropriate Indications Outlined for Peripheral Vascular Testing
A multidisciplinary panel of cardiologists, vascular surgeons, radiologists, and other experts has issued appropriate use guidelines to help clinicians make decisions when ordering initial and follow-up testing for their patients with known or suspected peripheral vascular disease. The document, published online June 11, 2012, ahead of print in the Journal of the American College of Cardiology, suggests that almost half of the most common clinical indications for such testing are appropriate but sheds light on others that either require more evidence of clinical benefit or are not appropriate.
A writing committee chaired by Emile R. Mohler III, MD, of the University of Pennsylvania Health System (Philadelphia, PA), identified 255 common clinical scenarios in which noninvasive vascular testing via ultrasound or physiological testing is frequently considered. A 19-member multidisciplinary panel of physicians and technicians then assessed the appropriateness of each scenario with a score of 1 to 9 to designate:
- Appropriate use for specific indication (median 7 to 9)
- Uncertain use (median 4 to 6)
- Inappropriate use (median 1 to 3)
It is the first systematic and comprehensive evaluation of appropriate indications for vascular testing, such as ultrasound or functional means.
According to the committee, the “[c]urrent evidence base and clinical practice guidelines were used to develop and rate the clinical indications whenever available, although for certain indications, the available scientific literature was limited and clinical expertise played a larger role.”
One Third Uncertain, 1 in 5 Inappropriate
In a telephone interview with TCTMD, Dr. Mohler said the panelists came together for a face-to-face discussion of the rating for each indication. Overall, 117 indications (46%) were rated as ‘appropriate,’ 84 (33%) as ‘uncertain,’ and 54 (21%) as ‘inappropriate.’
“Our focus is to prevent inappropriate testing but also to guide what is appropriate,” Dr. Mohler said. “There very well may be some underuse of testing and that’s important, too. We are trying to use the medical literature to define these things for the clinician because frankly it’s better than having the insurance companies decide for the doctor what they are allowed to order.”
A consensus of ‘appropriate’ was found for most vascular studies where the indication for testing was clinical signs and symptoms and when it was necessary to establish a baseline after revascularization.
For example, use of cerebrovascular ultrasound was rated as appropriate for evaluation of the patient with suspected vertebrobasilar occlusive disease with posterior circulation symptoms, while carotid ultrasound was rated as appropriate for evaluation of suspected carotid artery dissection. The use of cerebrovascular ultrasound for assessment of asymptomatic patients with risk factors or comorbidities for carotid artery stenosis was deemed ‘uncertain’ but appropriate for assessment of occult cerebrovascular disease in patients with established atherosclerotic disease in other vascular territories.
Abdominal, Iliac Indications
Signs and symptoms considered appropriate indications for duplex evaluation of the abdominal aorta and iliac arteries include:
- Intermittent claudication
- Aneurysmal femoral or popliteal pulse
- Pulsatile abdominal mass
- Decreased or absent femoral pulse
- Abdominal or femoral bruit
Of interest, erectile dysfunction was considered an uncertain indication for duplex ultrasound of the aorta and iliac arteries. Inappropriate indications included nonspecific discomfort and swelling in lower extremities, fever of unknown origin, and hypertension.
Ultrasound screening of asymptomatic individuals for abdominal aortic aneurysm was considered ‘appropriate’ in men and women over age 60 who were known to have first-degree relatives with an abdominal aortic aneurysm, those between 65 and 75 years of age who were current or former smokers, and any current or former smoker over age 75. However, it was found to be ‘inappropriate’ for individuals under age 65 with no smoking history and ‘uncertain’ for those age 65 and older with no smoking history.
Also included in the ‘inappropriate’ category were:
- Ordering an ultrasound of the carotids in a patient at low risk for MI or stroke
- Screening for kidney artery disease in patients with peripheral artery disease when hypertension was well controlled on 1 medication
- Performing a follow-up study for a patient with a normal baseline study who has no new symptoms
More Work Still to Be Done
“We think this document gives physicians a body of knowledge to help understand whether the test is indicated for that indication and then also to help them with follow-up to know when they can perform the test again if they find disease,” Dr. Mohler said. “Even with very common scenarios such as carotid artery disease, there can be uncertainty depending on how many cases an individual clinicians sees, especially in knowing how to follow that up when they find a certain blockage such as 30%, 50%, 70%. So, we hope that by doing this work we are helping them out with their follow-up questions and providing a resource.”
Dr. Mohler said some areas in which the panel felt that more research is necessary include:
- Clinical and cost effectiveness of carotid artery duplex prior to CABG
- Cost-benefit analysis and utility of carotid duplex ultrasound for asymptomatic patients with atherosclerotic vascular disease in other vascular beds (eg, coronary or peripheral artery disease) and for patients with multiple atherosclerotic risk factors
- Optimal frequency of ultrasound examinations for surveillance of untreated internal carotid artery stenosis
“I have to congratulate the committee for doing a great job putting all these scenarios together,” J. Jeffrey Marshall, MD, of Northeast Georgia Heart Center (Gainesville, GA), told TCTMD in a telephone interview.
“These appropriate use criteria are becoming more important as we try to practice efficient medicine,” he added. “It’s important to point out, though, that they could not cover every possible clinical situation, so you have a limited number of scenarios—every patient is different. But I think the most important thing for clinicians to take away from this is that just because something is ‘uncertain’ does not mean it is inappropriate. We still don’t know everything in medicine. There still is some ‘art’ to medicine. . . . Clinical acumen is necessary in addition to having documents such as this to do the right procedure on the right patient at the right time.”
Mohler ER III, Gornik HL, Gerhard-Herman M, et al. ACCF/ACR/AIUM/ASE/ASN/ICAVL/SCAI/SCCT/SIR/SVM/SVS 2012 appropriate use criteria for peripheral vascular ultrasound and physiological testing part I: Arterial ultrasound and physiological testing. J Am Coll Cardiol. 2012;Epub ahead of print.
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- Dr. Mohler reports serving as a consultant for AMAG Pharmaceuticals, GlaxoSmithKline, and Merck; and receiving research support from Bristol-Myers Squibb, GlaxoSmithKline, and the National Institutes of Health.
- Dr. Marshall is president of SCAI, which collaborated on the document, although he was not a member of the panel.