What is the primary diagnostic method used to assess peripheral artery disease?

The primary diagnostic method used to assess peripheral artery disease (PAD) is the ankle-brachial index (ABI). This non-invasive test compares the blood pressure in the patient's ankle with the blood pressure in their arm. In individuals with PAD, blood flow to the limbs is reduced due to narrowing or blockage of the arteries. As a result, the blood pressure in the ankle will typically be lower than in the arm.

The ABI provides a clear, quantifiable measure of arterial sufficiency and can help diagnose the presence and severity of PAD. It is preferred in clinical practice due to its simplicity, cost-effectiveness, and the ability to provide immediate results without the need for extensive imaging or invasive techniques.

Other diagnostic options, while useful in certain contexts, do not serve as the primary assessment tool for PAD. For example, CT angiography is more invasive and is generally used to evaluate complex vascular conditions or for surgical planning rather than as a first-line diagnostic tool. Venous duplex ultrasound is focused on venous circulation and is not primarily used for PAD diagnosis. Magnetic resonance imaging, while it can provide detailed vascular images, is not routinely used for PAD due to its higher cost and limited availability in some settings. Thus, the ABI remains the cornerstone for