Validation of a Novel Oscillometric-Based Algorithm for Determination of the Ankle-Brachial Index

Peripheral arterial disease (PAD) is a highly prevalent medical condition. Patients with PAD are usually diagnosed on the basis of the ankle-brachial index. The ankle-brachial index is the ratio of ankle pressure to arm pressure after measurement of blood pressures in the arms and legs using a Doppler device. The need for dedicated equipment and trained personnel, along with the time required to perform the test, have been identified as barriers to widespread implementation of ankle-brachial index screening. The use of automated oscillometric devices for blood pressure measurement has been applied to leg pressure measurement and determination of the ankle-brachial index with variable success. It will be beneficial to investigate a reliable oscillometric-based procedure that can accurately measure leg pressures for the ankle-brachial index across the entire spectrum of PAD severity.

In a previous pilot study completed in 2009 (IRB 08-823), the investigators gathered data from N=60 subjects which allowed for mathematical analysis of oscillometric waveforms derived from the lower extremities as compared to Doppler-based measurements of blood pressure. We used signal processing analysis and regression techniques to develop a two-step algorithm which will allow for accurate interpretation of oscillometric waveforms in normal/mild vs. moderate/severely diseased limb and accurate calculation of ankle pressure across the spectrum of peripheral artery disease severity.

This proposed project will validate this novel oscillometric ABI algorithm in a population of patients who have been identified as at risk for PAD and for whom screening ABI has been recommended by multiple professional organizations (AHA/ACC and American Diabetes Association). Arm, ankle, and toe pressure measurements will be made in the supine position using Doppler, oscillometric methods, and a photoplethysmographic sensor. The ankle-brachial index and toe-brachial index will be calculated.

Study Overview

• Status: Completed
• Conditions: Peripheral Arterial Disease
• Intervention / Treatment: Device: Blood Pressure Measurement

• Study Type: Observational
• Enrollment (Anticipated): 161

Contacts and Locations

Study Locations

• United States
  • Ohio
    • Cleveland, Ohio, United States, 44195
      • Cleveland Clinic

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients presenting to the non-invasive vascular laboratory or another outpatient clinic in the Heart and Vascular Institute at Cleveland Clinic.

Description

Inclusion Criteria:

• At least 70 years of age
• At least 50 years of age with a history of diabetes mellitus or tobacco smoking (>100 cigarettes in their lifetime)
• Ambulatory Outpatient

Exclusion Criteria:

• Unable to give informed consent
• Unable to lie supine for at least 15 minutes
• Known non-compressible vessels on prior laboratory studies (ABI>1.3 on either side)

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Cross-Sectional

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Suspected Arterial Disease; Patients with known or suspected arterial disease and patients screened using AHA/ACC criteria for P.A.D.	Device: Blood Pressure Measurement; Systolic blood pressures will be obtained from each limb using Doppler, oscillometric, and photoplethysmographic (PPG) modalities.

Collaborators and Investigators

• Sponsor: Summit Doppler Systems, Inc.
• Collaborators: The Cleveland Clinic

Study record dates

Study Major Dates

• Study Start: October 1, 2010
• Primary Completion (Actual): January 1, 2011
• Study Completion (Actual): January 1, 2011

Study Registration Dates

• First Submitted: July 15, 2010
• First Submitted That Met QC Criteria: July 16, 2010
• First Posted (Estimate): July 19, 2010

Study Record Updates

• Last Update Posted (Estimate): February 24, 2011
• Last Update Submitted That Met QC Criteria: February 22, 2011
• Last Verified: February 1, 2011

More Information

Terms related to this study

• Keywords: Peripheral; Vascular; Arterial
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Atherosclerosis; Peripheral Arterial Disease; Peripheral Vascular Diseases
• Other Study ID Numbers: CCF IRB 10-513