Professional Practice Guide -FCSV-EN

14 Professional Practice Guide 3.2 SCREENING TEST After the medical questionnaire and physical examination, a physician who suspects PAD should attempt to confirm the diagnosis and assess its severity using more advanced investigative methods. In general, this process begins by calculating the ankle-brachial index (ABI). This simple, low- cost, and non-invasive screening test consists of calculating the ratio between the highest systolic pressure measured at each ankle and the systolic pressure measured in the arms. The ABI has a sensitivity of 95% and a specificity of 99% for the detection of PAD.² After a rest period of 15–30 minutes, the patient is placed in the supine position, and blood pressure is measured at the arms and ankles using a blood pressure cuff and a Doppler probe (see Figure 2: Interpreting Ankle-Brachial Index Values). In some patients—particularly those with diabetes or chronic kidney disease—the arteries of the legs may be too rigid for accurate pressure measurement due to calcium deposits in the arterial walls. In this situation, pressure measurement at the great toe is preferred. Systolic pressure of the left arm Systolic pressure of the right arm Le dorsalis pedis artery Le posterior tibial artery Right dorsalis pedis artery Right posterior tibial artery Highest pressure of the two measurements taken at the left ankle Highest pressure of the two arms Highest pressure of the two measurements taken at the right ankle Highest pressure of the two arms Ankle- Brachial Index Interpretation > 1.40 Non-compressible artery 1.00 - 1.40 Normal value 0.91 - 0.99 Borderline value 0.41 - 0.90 Mild to moderate PAD < 0.41 Severe PAD Ӌ FIGURE 2. Ӌ INTERPRETING ANKLE-BRACHIAL INDEX VALUES 3. Evaluating Peripheral Artery Disease (PAD)