If ABI is greater than 0.9 but suspicion for PAD remains high, what is a potential next step?

• A. Rest and post-exercise ABI measurements
• B. CTA or MRA immediately
• C. Surgery
• D. Ignore and treat risk factors only

Answer: (A)

When resting measurements look normal but there is still strong suspicion for PAD, the test strategy should focus on how the arteries respond to exercise. A normal or high resting ABI can occur even with disease, especially if vessels are calcified or if symptoms only appear with activity. Post-exercise (treadmill) ABI testing uncovers flow limitation that isn’t evident at rest. If the ankle pressure falls significantly after exercise—or if the post-exercise ABI drops to around 0.90 or less—it indicates hemodynamically significant PAD despite a normal resting result. This approach is noninvasive and guides further steps, such as duplex ultrasound or targeted imaging if PAD is confirmed. Immediate CTA/MRA or surgical intervention isn’t warranted based solely on resting ABI with ongoing suspicion, and simply ignoring symptoms isn’t appropriate.