Automatic ABI measurements in primary care - agreement with patients’ symptoms and examination

Aleksandra Danieluk

Keywords: ankle-brachial index, peripheral artery disease

Peripheral artery disease (PAD) increases cardiovascular risk even in asymptomatic patients. Accurate and efficient diagnostic tools for PAD patients are needed. Recently there have been attempts to establish a reliable method of automated ankle-brachial index (ABI) identification. This raises a question whether such methods can be feasible in primary care.

Research questions:
Do automatic ABI measurements provide new information about patients at risk of PAD?

Cross-sectional study performed at a primary care office on patients over 60 years old. Physical examination aimed at PAD diagnosis and Edinburgh questionnaire was performed as well as an automatic ABI measurement. Automatic ABI measurements were taken with use of Dopplex Ability Automatic ABI System. Incidence of lack of pulse on posterior tibial artery, PAD suspicion based on the Edinburgh questionnaire and incorrect ABI results were compared.

Initial results of the study are presented, with 42 patients included at this point. 54.76% of patients had an abnormal ABI result (ABI lower than 0.98, higher than 1.3 or an incorrect pulse volume waveform). Normal ABI ranges for Dopplex Ability were established in this study based on publication by Lewis et al. When establishing ABI ranges at 0.9-1.3, only 40.48% of patients had an abnormal ABI result. 73.91% of patients with an abnormal ABI result had posterior tibial pulse present and Edinburgh questionnaire negative for PAD symptoms. This accounted for 40.48% of all the patients.

Automatic ABI allows to include more patients into PAD suspicion group, including patients with no typical changes in physical examination or characteristic symptoms.

Points for discussion: