FlowMet-R Blood Flow Measurement for the Diagnosis of Peripheral Artery Disease and Critical Limb Ischemia

NCT04120610 | Terminated Results FDA Device

• 1 other identifier: 30081919
• Study Type: observational
• Target: 195
• Locations: 1 country
• Sites: 5

Brief Summary

Non-randomized, multi-center, longitudinal study of healthy subjects and subjects with PAD who are scheduled for ABI, TBI, and either Duplex Ultrasound or Angiographic assessments in a vascular clinic.

Conditions

Peripheral Artery Disease

Keywords

Peripheral Artery Disease; Claudication; Critical Limb Ischemia

Outcome Measures

Primary Outcomes (1)

• Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI

  Primary objective is to determine the efficacy of FlowMet-R measurements in diagnosing PAD \& CLI. All patients were combined from healthy \& PAD groups to form one cohort, ABI and TBI were then used to assign patients in PAD (1), PAD (2) \& CLI. FlowMet-R data (comprised of blood flow measurements and/or feature analysis of the blood flow waveform) were used to create a predictive model of PAD severity. This model was used to generate diagnostic receiver operating characteristic (ROC) curves for PAD and, independently, CLI, at three time points. ROC curves were used to compute the peak sensitivity, peak specificity, and area under the curve (AUC) at the initial, 3-month and 6-month time points. Sensitivity, specificity and AUC are unitless. Sensitivity is the percentage of true positives \& specificity is the percentage of true negatives at the location on the ROC curve where it was closest to the upper left of the unit square from an ROC curve (peak).

  Initial, three month, and six month time points.

Secondary Outcomes (6)

• Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention

  Within three and six months following initial visit

• Sensitivity, Specificity and Area Under the Curve (AUC) of FlowMet-R in Diagnosing Significant Stenosis

  Initial visit

• Stenosis Percentage

  Initial visit

• Changes in Ankle Brachial Index (ABI)

  Within three and six months following initial visit.

• Changes in Toe Brachial Index (TBI)

  Within three and six months following initial visit.

Study Arms (2)

Healthy

Healthy cohort is an age-matched population (over 40 years old) without history of PAD or suspected PAD. Healthy cohort will receive FlowMet-R measurement, Ankle Brachial Index (ABI), and Toe Brachial Index (TBI) measurements.

Diagnostic Test: FlowMet-R; Diagnostic Test: ABI; Diagnostic Test: TBI

Peripheral Artery Disease

PAD cohort is all-comers to the vascular lab that are scheduled to undergo assessment for Peripheral Artery Disease (PAD) or have a planned endovascular or surgical intervention to address PAD and will receive FlowMet-R measurement in addition to their routine standard of care.

Diagnostic Test: FlowMet-R; Diagnostic Test: ABI; Diagnostic Test: TBI

Interventions

FlowMet-R DIAGNOSTIC_TEST

FlowMet-R is a noninvasive blood flow measurement.

Healthy; Peripheral Artery Disease

ABI DIAGNOSTIC_TEST

Ankle Brachial Index is a ratio-metric blood pressure measurement in the ankle and arm.

Healthy; Peripheral Artery Disease

TBI DIAGNOSTIC_TEST

Ankle Brachial Index is a ratio-metric blood pressure measurement in the toe and arm.

Healthy; Peripheral Artery Disease

Eligibility Criteria

• Age: 40 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

The PAD cohort population is persons who have known or suspected peripheral artery disease, and are being seen at a vascular clinic for evaluation. The Healthy cohort population is adult persons over 40 without history of PAD and who are not currently suspected of suffering from PAD.

You may qualify if:

• PAD Positive Cohort
• Subject meets PAD positive criteria
• Subject is willing and able to provide informed consent
• Subject is willing and able to comply with study procedures
• Subject is able to understand the study procedures
• Subject is scheduled for vascular examination that includes noninvasive assessments as standard of care: ABI, TBI, and either a Duplex Ultrasound or Angiogram
• Healthy Cohort
• Subject is willing and able to provide informed consent.
• Subject is willing and able to comply with the study procedures.
• Subject is able to understand the study procedures.
• Subject has no history of positive PAD diagnosis, and is not currently suspected of having PAD.

You may not qualify if:

• PAD Positive Cohort
• Subject is under 40 or unable to consent.
• Subject has any medical condition, which, in the judgment of the Investigator and/or designee, makes the subject a poor candidate for the investigational study.
• Subject is excluded from analysis if no stenosis is found during Doppler but Tibial disease is suspected and Tibial ultrasound is not able to be performed.
• Subject does not have a suitable finger to attach the FlowMet-R probe.
• Subject does not have a suitable 1st or 2nd digit to attach FlowMet-R probe on the limb of interest.
• Subject has undergone revascularization within the last 90 days
• Subject cannot lay safely in a supine position.
• Healthy Cohort
• Subject is under 40 or unable to consent.
• Subject has any medical condition, which, in the judgment of the Investigator and/or designee, makes the subject a poor candidate for the investigational study.
• One or more limbs has a prior or current diagnosis of PAD, or is reasonably suspected of having a diagnosis of PAD.
• Subject does not have a suitable finger to attach the FlowMet-R probe.
• Subject does not have a suitable 1st or 2nd digit to attach FlowMet-R probe.
• Subject has undergone revascularization within the last 90 days

Sponsors & Collaborators

• Medtronic Endovascular: lead
• ICON plc: collaborator

Study Sites (5)

The Iowa Clinic

Des Moines, Iowa, 50266, United States

Location

Mercy Research

Chesterfield, Missouri, 63017, United States

Location

The Mt. Sinai Hospital

New York, New York, 10029, United States

Location

Ohio Health

Columbus, Ohio, 43214, United States

Location

Ascension Seton

Austin, Texas, 78705, United States

Location

MeSH Terms

Conditions

Peripheral Arterial Disease; Intermittent Claudication; Chronic Limb-Threatening Ischemia

Condition Hierarchy (Ancestors)

Atherosclerosis; Arteriosclerosis; Arterial Occlusive Diseases; Vascular Diseases; Cardiovascular Diseases; Peripheral Vascular Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Chronic Disease; Disease Attributes; Pathologic Processes; Ischemia

Limitations and Caveats

The study was terminated by Medtronic prior to completing enrollment. Difficulties with enrollment and limited compliance partially related to the COVID-19 pandemic limited the conclusions. Analyses described in the protocol were computed, but no hypothesis tests were completed. The AUC and its 95% CI are provided to assess the potential for the FlowMet device to classify CLI, PAD (1), PAD (2) at 0-, 3-, and 6-months, reintervention within 3- and 6-months, and significant stenosis.

Results Point of Contact

• Title: Janki Shah
• Organization: Medtronic

janki.shah@medtronic.com

732-266-2503

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 6 Months
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 7, 2019
• First Posted: October 9, 2019
• Study Start: December 9, 2019
• Primary Completion: November 21, 2022
• Study Completion: November 21, 2022
• Last Updated: April 11, 2025
• Results First Posted: April 11, 2025

Record last verified: 2024-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (5)