Peripheral Artery Disease
Conditions
Keywords
Peripheral Artery Disease, Claudication, Critical Limb Ischemia
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.
Detailed description
Patients scheduled for peripheral vascular examination and healthy controls will be measured with the FlowMet-R, a noninvasive blood flow monitor, and compared to gold standard diagnostics - ABI, TBI, and Doppler Ultrasound. Sensitivity and specificity of the FlowMet-R device output in diagnosing PAD and CLI will be assessed on initial visit, 3-month followup, and 6-month followup.
Interventions
DIAGNOSTIC_TESTFlowMet-R
FlowMet-R is a noninvasive blood flow measurement.
DIAGNOSTIC_TESTABI
Ankle Brachial Index is a ratio-metric blood pressure measurement in the ankle and arm.
DIAGNOSTIC_TESTTBI
Ankle Brachial Index is a ratio-metric blood pressure measurement in the toe and arm.
Sponsors
ICON plc
Medtronic Endovascular
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
40 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
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.
Exclusion criteria
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Initial, three month, and six month time points. | 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). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Sensitivity, Specificity and Area Under the Curve (AUC) of FlowMet-R in Diagnosing Significant Stenosis | Initial visit | ROC curves for predicting a patient has significant stenosis, defined by greater than 50%, in at least one peripheral artery will be generated using FlowMet-R measurement data. ROC curves will be used to compute the peak sensitivity, peak specificity, and area under the curve (AUC) at the initial visit. 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). |
| Stenosis Percentage | Initial visit | A correlation test will be performed between FlowMet-R and stenosis percentage. The correlations between the acceleration time from the FlowMet-R device and peripheral artery stenosis will be computed using a Pearson correlation. Correlation will be computed using available FlowMet-R data from PAD participants with significant stenosis, defined by greater than 50%, in at least one peripheral artery at the initial visit. |
| Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention | Within three and six months following initial visit | ROC curves for predicting if a patient will undergo intervention following their initial visit were generated using FlowMet-R measurement data. ROC curves were used to compute the peak sensitivity, peak specificity, and area under the curve (AUC) within the 3-month and 6-month time points, separately. 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). |
| Changes in Toe Brachial Index (TBI) | Within three and six months following initial visit. | The outcome TBI is a ratio of blood pressures in the arm and toe. Values less than 1 generally indicate narrower arteries. The outcome used the change in TBI for: 0 to 3 months, 0 to 6 months, and 3 to 6 months. The correlation with this outcome was estimated using the corresponding change in acceleration time from the FlowMet-R device. |
| Changes in Rutherford Classification | Within three and six months following initial visit. | Rutherford Classification is an ordinal scale that ranges from 0 to 6 and is used to measure peripheral arterial disease severity and chronic limb threatening ischemia. Higher values indicate more severe disease. The changes for Rutherford Classification were computed for: 0 to 3 months, 0 to 6 months, and 3 to 6 months. The correlation with this outcome was estimated using the corresponding change in acceleration time from the FlowMet-R device. |
| Changes in Ankle Brachial Index (ABI) | Within three and six months following initial visit. | The outcome ABI is a ratio of blood pressures in the arm and ankle. Values less than 1 generally indicate narrower arteries. The outcome used the change in ABI for: 0 to 3 months, 0 to 6 months, and 3 to 6 months. The correlation with this outcome was estimated using the corresponding change in acceleration time from the FlowMet-R device. |
Countries
United States
Participant flow
Pre-assignment details
205 subjects were consented in the study. Of the 205 subjects, 10 subjects were screen fails due to I/E criteria, resulting in 195 total subjects enrolled. There were limitations discovered in the study design during enrollment due to classification of PAD and CLI from respective sites. Patients were categorized based on observed ABI, TBI and Rutherford Classification regardless of enrollment cohort.
Participants by arm
| Arm | Count |
|---|---|
| Healthy Healthy cohort includes patients over 40 years old without history of PAD or suspected PAD, where the ABI\>0.9 and ABI≤1.4 or TBI\>0.7. Healthy cohort will receive FlowMet-R measurement, Ankle Brachial Index (ABI), and Toe Brachial Index (TBI) measurements.
FlowMet-R: FlowMet-R is a noninvasive blood flow measurement.
ABI: Ankle Brachial Index is a ratio-metric blood pressure measurement in the ankle and arm.
TBI: Ankle Brachial Index is a ratio-metric blood pressure measurement in the toe and arm. | 63 |
| Healthy Healthy cohort includes patients over 40 years old without history of PAD or suspected PAD, where the ABI\>0.9 and ABI≤1.4 or TBI\>0.7. Healthy cohort will receive FlowMet-R measurement, Ankle Brachial Index (ABI), and Toe Brachial Index (TBI) measurements.
FlowMet-R: FlowMet-R is a noninvasive blood flow measurement.
ABI: Ankle Brachial Index is a ratio-metric blood pressure measurement in the ankle and arm.
TBI: Ankle Brachial Index is a ratio-metric blood pressure measurement in the toe and arm. | 77 |
| Peripheral Artery Disease (Including Critical Limb Ischemia) 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.
PAD (2) cohort patients are defined by ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 without exhibition of symptoms and regardless of Rutherford Category. CLI cohort patients are defined by an exhibition of chronic rest pain and active wounds, verified by TBI\<0.3. PAD (2) and CLI patients will receive FlowMet-R measurement in addition to their routine standard of care.
FlowMet-R: FlowMet-R is a noninvasive blood flow measurement.
ABI: Ankle Brachial Index is a ratio-metric blood pressure measurement in the ankle and arm.
TBI: Ankle Brachial Index is a ratio-metric blood pressure measurement in the toe and arm. | 131 |
| Peripheral Artery Disease (Including Critical Limb Ischemia) 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.
PAD (2) cohort patients are defined by ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 without exhibition of symptoms and regardless of Rutherford Category. CLI cohort patients are defined by an exhibition of chronic rest pain and active wounds, verified by TBI\<0.3. PAD (2) and CLI patients will receive FlowMet-R measurement in addition to their routine standard of care.
FlowMet-R: FlowMet-R is a noninvasive blood flow measurement.
ABI: Ankle Brachial Index is a ratio-metric blood pressure measurement in the ankle and arm.
TBI: Ankle Brachial Index is a ratio-metric blood pressure measurement in the toe and arm. | 148 |
| Total | 419 |
Baseline characteristics
| Characteristic | Healthy | Total | Peripheral Artery Disease (Including Critical Limb Ischemia) |
|---|---|---|---|
| Age, Continuous | 60.0 years STANDARD_DEVIATION 13 | 67.0 years STANDARD_DEVIATION 11.8 | 70.4 years STANDARD_DEVIATION 9.6 |
| Body Mass Index | 28.7 lbs/(in^2)*703 STANDARD_DEVIATION 7.3 | 28.4 lbs/(in^2)*703 STANDARD_DEVIATION 6.3 | 28.2 lbs/(in^2)*703 STANDARD_DEVIATION 5.7 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 4 Participants | 36 Participants | 32 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 59 Participants | 158 Participants | 99 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Height | 66.1 inches STANDARD_DEVIATION 4.1 | 66.4 inches STANDARD_DEVIATION 4.2 | 66.5 inches STANDARD_DEVIATION 4.3 |
| Medical History Chronic Obstructive Pulmonary Disease (COPD) | 3 participants | 27 participants | 24 participants |
| Medical History Clots or deep vein thrombosis (DVT) | 0 participants | 7 participants | 7 participants |
| Medical History Type 1 diabetes | 2 participants | 5 participants | 3 participants |
| Medical History Type 2 diabetes | 18 participants | 83 participants | 65 participants |
| Medical History Venous Disease | 12 participants | 47 participants | 35 participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 1 Participants | 2 Participants | 1 Participants |
| Race (NIH/OMB) Black or African American | 5 Participants | 26 Participants | 21 Participants |
| Race (NIH/OMB) More than one race | NA Participants | NA Participants | NA Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 2 Participants | 33 Participants | 31 Participants |
| Race (NIH/OMB) White | 55 Participants | 133 Participants | 78 Participants |
| Region of Enrollment United States | 63 participants | 194 participants | 131 participants |
| Sex: Female, Male Female | 35 Participants | 91 Participants | 56 Participants |
| Sex: Female, Male Male | 28 Participants | 103 Participants | 75 Participants |
| Smoking Status Current | 5 Participants | 36 Participants | 31 Participants |
| Smoking Status Never | 34 Participants | 67 Participants | 33 Participants |
| Smoking Status Previous | 24 Participants | 91 Participants | 67 Participants |
| Weight | 183.4 pounds STANDARD_DEVIATION 44.8 | 180.5 pounds STANDARD_DEVIATION 43.1 | 178.4 pounds STANDARD_DEVIATION 42.6 |
| Wound History | 4 Participants | 18 Participants | 14 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 52 | 4 / 143 |
| other Total, other adverse events | 0 / 52 | 2 / 143 |
| serious Total, serious adverse events | 0 / 52 | 6 / 143 |
Outcome results
Primary
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).
Time frame: Initial, three month, and six month time points.
Population: Sensitivity, specificity and area under the curve (AUC) were calculated for PAD (1) vs. not PAD (1), PAD (2) vs not PAD (2), and CLI vs. not CLI at initial, three-month and six-month timepoints.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Specificity (6 months) | 0.58 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Sensitivity (6 months) | 0.74 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Area Under the Curve (Initial) | 0.84 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Specificity (Initial) | 0.78 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Sensitivity (3 months) | 0.52 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Sensitivity (Initial) | 0.80 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Specificity (3 months) | 0.63 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Area Under the Curve (6 months) | 0.62 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Area Under the Curve (3 months) | 0.58 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Specificity (6 months) | 0.67 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Specificity (3 months) | 0.77 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Sensitivity (6 months) | 0.73 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Area Under the Curve (6 months) | 0.67 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Specificity (Initial) | 0.86 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Area Under the Curve (Initial) | 0.87 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Sensitivity (3 months) | 0.57 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Area Under the Curve (3 months) | 0.67 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Sensitivity (Initial) | 0.78 probability |
| Critical Limb Ischemia (CLI) vs Not CLI | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Sensitivity (3 months) | 1.00 probability |
| Critical Limb Ischemia (CLI) vs Not CLI | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Area Under the Curve (Initial) | 0.86 probability |
| Critical Limb Ischemia (CLI) vs Not CLI | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Sensitivity (Initial) | 0.82 probability |
| Critical Limb Ischemia (CLI) vs Not CLI | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Sensitivity (6 months) | 1.00 probability |
| Critical Limb Ischemia (CLI) vs Not CLI | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Area Under the Curve (3 months) | 0.95 probability |
| Critical Limb Ischemia (CLI) vs Not CLI | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Specificity (6 months) | 0.59 probability |
| Critical Limb Ischemia (CLI) vs Not CLI | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Specificity (3 months) | 0.91 probability |
| Critical Limb Ischemia (CLI) vs Not CLI | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Area Under the Curve (6 months) | 0.79 probability |
| Critical Limb Ischemia (CLI) vs Not CLI | Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI | Specificity (Initial) | 0.78 probability |
Secondary
Changes in Ankle Brachial Index (ABI)
The outcome ABI is a ratio of blood pressures in the arm and ankle. Values less than 1 generally indicate narrower arteries. The outcome used the change in ABI for: 0 to 3 months, 0 to 6 months, and 3 to 6 months. The correlation with this outcome was estimated using the corresponding change in acceleration time from the FlowMet-R device.
Time frame: Within three and six months following initial visit.
Population: Limbs of participants with ABI measured at 0, 3, and 6 months. ABI was not collected in at least 2 of the 86 limbs included in the overall analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Peripheral Artery Disease (1) vs Not PAD | Changes in Ankle Brachial Index (ABI) | 0.09 mmHg / mmHg | Standard Deviation 0.23 |
| Peripheral Artery Disease (2) vs Not PAD | Changes in Ankle Brachial Index (ABI) | 0.08 mmHg / mmHg | Standard Deviation 0.31 |
| Critical Limb Ischemia (CLI) vs Not CLI | Changes in Ankle Brachial Index (ABI) | 0.03 mmHg / mmHg | Standard Deviation 0.22 |
Comparison: Correlation of change in acceleration time and ABI. Descriptive analysis of endpoint with no hypothesis.95% CI: [-0.46, -0.03]
Comparison: Correlation of change in acceleration time and ABI. Descriptive analysis of endpoint with no hypothesis.95% CI: [-0.51, -0.12]
Comparison: Correlation of change in acceleration time and ABI. Descriptive analysis of endpoint with no hypothesis.95% CI: [-0.38, 0.14]
Secondary
Changes in Rutherford Classification
Rutherford Classification is an ordinal scale that ranges from 0 to 6 and is used to measure peripheral arterial disease severity and chronic limb threatening ischemia. Higher values indicate more severe disease. The changes for Rutherford Classification were computed for: 0 to 3 months, 0 to 6 months, and 3 to 6 months. The correlation with this outcome was estimated using the corresponding change in acceleration time from the FlowMet-R device.
Time frame: Within three and six months following initial visit.
Population: Limbs of participants with Rutherford Class measured at 0, 3, and 6 months. Rutherford Class was not collected in at least 2 of the 86 limbs included in the overall analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Peripheral Artery Disease (1) vs Not PAD | Changes in Rutherford Classification | -0.39 units on a scale | Standard Deviation 1.4 |
| Peripheral Artery Disease (2) vs Not PAD | Changes in Rutherford Classification | -0.62 units on a scale | Standard Deviation 1.5 |
| Critical Limb Ischemia (CLI) vs Not CLI | Changes in Rutherford Classification | -0.26 units on a scale | Standard Deviation 1.2 |
Comparison: Correlation of change in acceleration time and Rutherford Classification. Descriptive analysis of endpoint with no hypothesis.95% CI: [-0.08, 0.36]
Comparison: Correlation of change in acceleration time and Rutherford Classification. Descriptive analysis of endpoint with no hypothesis.95% CI: [-0.02, 0.39]
Comparison: Correlation of change in acceleration time and Rutherford Classification. Descriptive analysis of endpoint with no hypothesis.95% CI: [-0.02, 0.47]
Secondary
Changes in Toe Brachial Index (TBI)
The outcome TBI is a ratio of blood pressures in the arm and toe. Values less than 1 generally indicate narrower arteries. The outcome used the change in TBI for: 0 to 3 months, 0 to 6 months, and 3 to 6 months. The correlation with this outcome was estimated using the corresponding change in acceleration time from the FlowMet-R device.
Time frame: Within three and six months following initial visit.
Population: Limbs of participants with TBI measured at 0, 3, and 6 months.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Peripheral Artery Disease (1) vs Not PAD | Changes in Toe Brachial Index (TBI) | 0.08 mmHg / mmHg | Standard Deviation 0.24 |
| Peripheral Artery Disease (2) vs Not PAD | Changes in Toe Brachial Index (TBI) | 0.10 mmHg / mmHg | Standard Deviation 0.25 |
| Critical Limb Ischemia (CLI) vs Not CLI | Changes in Toe Brachial Index (TBI) | 0.02 mmHg / mmHg | Standard Deviation 0.18 |
Comparison: Correlation of change in acceleration time and TBI. Descriptive analysis of endpoint with no hypothesis.95% CI: [-0.52, -0.12]
Comparison: Correlation of change in acceleration time and TBI. Descriptive analysis of endpoint with no hypothesis.95% CI: [-0.52, -0.15]
Comparison: Correlation of change in acceleration time and TBI. Descriptive analysis of endpoint with no hypothesis.95% CI: [-0.47, 0.02]
Secondary
Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention
ROC curves for predicting if a patient will undergo intervention following their initial visit were generated using FlowMet-R measurement data. ROC curves were used to compute the peak sensitivity, peak specificity, and area under the curve (AUC) within the 3-month and 6-month time points, separately. 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).
Time frame: Within three and six months following initial visit
Population: PAD (1), PAD (2) and CLI participants who underwent vascular intervention following their initial visit.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention | Sensitivity | 0.60 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention | Specificity | 0.49 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention | Area Under the Curve (AUC) | 0.52 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention | Sensitivity | 0.59 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention | Specificity | 0.56 probability |
| Peripheral Artery Disease (2) vs Not PAD | Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention | Area Under the Curve (AUC) | 0.54 probability |
Secondary
Sensitivity, Specificity and Area Under the Curve (AUC) of FlowMet-R in Diagnosing Significant Stenosis
ROC curves for predicting a patient has significant stenosis, defined by greater than 50%, in at least one peripheral artery will be generated using FlowMet-R measurement data. ROC curves will be used to compute the peak sensitivity, peak specificity, and area under the curve (AUC) at the initial visit. 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).
Time frame: Initial visit
Population: All PAD participants with significant stenosis, defined by greater than 50%, in at least one peripheral artery and generated using FlowMet-R measurement data.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity, Specificity and Area Under the Curve (AUC) of FlowMet-R in Diagnosing Significant Stenosis | Sensitivity | 0.61 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity, Specificity and Area Under the Curve (AUC) of FlowMet-R in Diagnosing Significant Stenosis | Specificity | 0.61 probability |
| Peripheral Artery Disease (1) vs Not PAD | Sensitivity, Specificity and Area Under the Curve (AUC) of FlowMet-R in Diagnosing Significant Stenosis | Area Under the Curve (AUC) | 0.63 probability |
Secondary
Stenosis Percentage
A correlation test will be performed between FlowMet-R and stenosis percentage. The correlations between the acceleration time from the FlowMet-R device and peripheral artery stenosis will be computed using a Pearson correlation. Correlation will be computed using available FlowMet-R data from PAD participants with significant stenosis, defined by greater than 50%, in at least one peripheral artery at the initial visit.
Time frame: Initial visit
Population: All limbs of PAD participants with significant stenosis, defined by greater than 50%, in at least one peripheral artery and generated using FlowMet-R measurement data.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Peripheral Artery Disease (1) vs Not PAD | Stenosis Percentage | 67.9 percentage of stenosis | Standard Deviation 32.5 |
Comparison: Descriptive analysis of endpoint with no hypothesis.95% CI: [0.1, 0.41]