There are a number of points raised by Dr Matz. First, he questions whether an abnormal ABI adds value to readily available proven diagnostic and therapeutic protocols. He comments specifically about a good history review. It is notoriously difficult to obtain a diagnosis of PAD from a history review because many patients are asymptomatic or do not present with classic symptoms.1- 3 Only around one third of people with PAD (as defined by ABI <0.9) will report classic claudication symptoms. A further third will not mention their symptoms to their physician or will have confused them with a musculoskeletal diagnosis. The remaining third will have no relevant symptoms whatsoever. All of these people are at increased risk of future cardiovascular events, whether they are symptomatic or not. The ABI test identifies many at-risk patients who would not be detected by taking a conventional history, and would not, therefore, be treated aggressively for vascular risk factors.
Belch JJF. Cost-effective, Risk-Free, Evidence-Based Medicine—Reply. Arch Intern Med. 2003;163(22):2795-2796. doi:10.1001/archinte.163.22.2795-a