investigations in peripheral arterial disease
Last edited 03/2021 and last reviewed 05/2021
Routine investigations related to cardiovascular disease include fasting glucose and lipids.
Diagnosis of peripheral arterial disease (PAD) (1)
- a person should be assessed for PAD if:
- has symptoms suggestive of peripheral arterial disease or
- has diabetes, non-healing wounds on the legs or feet or unexplained leg pain or
- are being considered for interventions to the leg or foot or
- need to use compression hosiery
- if PAD is suspected the:
- ask about the presence and severity of possible symptoms of intermittent claudication and critical limb ischaemia
- examine the legs and feet for evidence of critical limb ischaemia, for example ulceration
- examinine the femoral, popliteal and foot pulses
- measure the ankle brachial pressure index
- imaging for revascularisation
- duplex ultrasound as first-line imaging if PAD for whom revascularisation is being considered
- contrast-enhanced magnetic resonance angiography is indicated if PAD in (after duplex ultrasound) before considering revascularisation
- computed tomography angiography should be used in patient with PAD who
need further imaging (after duplex ultrasound) if contrast-enhanced magnetic
resonance angiography is contraindicated or not tolerated
-
with respect to diagnosing peripheral arterial disease in people with diabetes
- do not exclude a diagnosis of peripheral arterial disease in people with diabetes based on a normal or raised ankle brachial pressure index alone
- do not use pulse oximetry for diagnosing peripheral arterial disease in people with diabetes
Notes:
- noninvasive imaging modalities, include duplex ultrasonography, magnetic
resonance angiography (MRA), and computed tomography angiography (CTA) (2)
- duplex ultrasonography has a high specificity of 95% and a somewhat lower sensitivity of 88% for detecting hemodynamically significant lesions (>50% stenosis or occlusion
- gadolinium-enhanced MRA appears to be more accurate than duplex ultrasonography, with a specificity of about 96% and a sensitivity of about 98%
- computed tomography angiography
- thinner slices, higher spatial resolution, and improvement of multidetector computed tomographic (CT) scanners enable scanning of the whole vascular tree in a limited period with a decreasing (but still substantial) amount of contrast medium. CTA has a reported sensitivity and specificity rates of around 98% for detecting PAD (2)
- claudication distance is an element in the history which quantifies the distance walked before claudication occurs
- exercise testing:
- motorised treadmill or step tests - foot pressure normally rises with exercise but drops in the presence of occlusive arterial disease
- the size of the pressure drop indicates the severity of the arterial insufficiency
Reference:
- 1) NICE (March 2018). Lower limb peripheral arterial disease: diagnosis and management
- 2) Schernthaner R, Stadler A, Lomoschitz F, et al. Multidetector CT angiography in the assessment of peripheral arterial occlusive disease: accuracy in detecting the severity, number, and length of stenoses. Eur Radiol. 2008;18(4):665-671.