Clinical situation
Peripheral arterial disease (PAD) is when the arteries, in this case, to the legs, become fully or partially blocked. This blockage most commonly occurs due to atherosclerotic (cholesterol) plaques.
Arterial blood brings oxygen and nutrients to the muscles of the legs, and when blocked may result in pain in the legs, also called intermittent claudication. Intermittent claudication is typically described as pain in the patient’s calf after walking a distance that goes away when the patient rests.
In advanced peripheral arterial disease, the patient may have pain in the legs at rest, and may develop leg ulcers and gangrene.
When a patient is first seen and suspected of having PAD, the underlying diagnosis is usually not difficult if a proper history and physical examination is performed.
For this purpose the Ankle brachial index (ankle systolic pressure/brachial systolic pressure) is usually measured.
Why is there a need for the Systoe?
Limitations of Ankle Brachial Index (ABI)
In the case of diabetic patients, old patients and renal failure patients, medial calcification (deposit of calcium on the middle part of the artery wall) of the tibial/peroneal arteries may prevent the measurement of the ABI pressure.
ABI measurement is impossible in
- 15 % of diabetic patients at the time of the diagnosis.
- 20 % of the diabetic patient present a PAD
- 30 % after 15 years
Weitz et al. Circulation. 1996; 94: 3026-3049
As the toe arteries are affected by medial calcification later than the leg arteries, the toe systolic pressure can be measured to circumvent the problem of medial calcification of the tibial/peroneal arteries. Toe pressures are a clinical indicator. For clinical purposes a normal Toe brachial Index (TBI = toe systolic pressure/brachial systolic pressure) is considered to be higher than 0.7
For any value less than that, the patient will be found to have some occlusive disease proximal to the recording site.
A major advantage of TBI is its use following the progress of disease and after any form of intervention.
The Atys SysToe can also be used in the following circumstances
- Triage patients before referral to vascular specialist
- Opportunistic Screening and follow up after intervention
- Wound and Ulcer healing
The Atys SysToe is a fully automatic clinically validated device that gives consistent readings which are not operator dependent. Using the SysToe clinicians can quickly determine whether a patient does or doesn’t have PAD without necessarily referring to a specialist Ultrasound Dept saving time and money
