Trial Outcomes & Findings for FlowMet-R Blood Flow Measurement for the Diagnosis of Peripheral Artery Disease and Critical Limb Ischemia (NCT NCT04120610)
NCT ID: NCT04120610
Last Updated: 2025-04-11
Results Overview
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).
Recruitment status
TERMINATED
Target enrollment
195 participants
Primary outcome timeframe
Initial, three month, and six month time points.
Results posted on
2025-04-11
Participant Flow
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.
Unit of analysis: limbs
Participant milestones
| Measure |
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.
|
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. PAD cohort 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.
|
|---|---|---|
|
Overall Study
STARTED
|
52 77
|
143 148
|
|
Overall Study
COMPLETED
|
52 77
|
83 89
|
|
Overall Study
NOT COMPLETED
|
0 0
|
60 59
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Data not collected for 4 healthy participants
Baseline characteristics by cohort
| Measure |
Healthy
n=77 limbs
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.
|
Peripheral Artery Disease (Including Critical Limb Ischemia)
n=148 limbs
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.
|
Total
n=225 limbs
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
60.0 years
STANDARD_DEVIATION 13.0 • n=63 Participants
|
70.4 years
STANDARD_DEVIATION 9.6 • n=131 Participants
|
67.0 years
STANDARD_DEVIATION 11.8 • n=194 Participants
|
|
Sex: Female, Male
Female
|
35 Participants
n=63 Participants
|
56 Participants
n=131 Participants
|
91 Participants
n=194 Participants
|
|
Sex: Female, Male
Male
|
28 Participants
n=63 Participants
|
75 Participants
n=131 Participants
|
103 Participants
n=194 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
4 Participants
n=63 Participants
|
32 Participants
n=131 Participants
|
36 Participants
n=194 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
59 Participants
n=63 Participants
|
99 Participants
n=131 Participants
|
158 Participants
n=194 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=63 Participants
|
0 Participants
n=131 Participants
|
0 Participants
n=194 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=63 Participants
|
0 Participants
n=131 Participants
|
0 Participants
n=194 Participants
|
|
Race (NIH/OMB)
Asian
|
1 Participants
n=63 Participants
|
1 Participants
n=131 Participants
|
2 Participants
n=194 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=63 Participants
|
0 Participants
n=131 Participants
|
0 Participants
n=194 Participants
|
|
Race (NIH/OMB)
Black or African American
|
5 Participants
n=63 Participants
|
21 Participants
n=131 Participants
|
26 Participants
n=194 Participants
|
|
Race (NIH/OMB)
White
|
55 Participants
n=63 Participants
|
78 Participants
n=131 Participants
|
133 Participants
n=194 Participants
|
|
Race (NIH/OMB)
More than one race
|
NA Participants
n=63 Participants
|
NA Participants
n=131 Participants
|
NA Participants
n=194 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
2 Participants
n=63 Participants
|
31 Participants
n=131 Participants
|
33 Participants
n=194 Participants
|
|
Region of Enrollment
United States
|
63 participants
n=63 Participants
|
131 participants
n=131 Participants
|
194 participants
n=194 Participants
|
|
Weight
|
183.4 pounds
STANDARD_DEVIATION 44.8 • n=59 Participants • Data not collected for 4 healthy participants
|
178.4 pounds
STANDARD_DEVIATION 42.6 • n=131 Participants • Data not collected for 4 healthy participants
|
180.5 pounds
STANDARD_DEVIATION 43.1 • n=190 Participants • Data not collected for 4 healthy participants
|
|
Height
|
66.1 inches
STANDARD_DEVIATION 4.1 • n=59 Participants • Data not collected for 4 healthy participants
|
66.5 inches
STANDARD_DEVIATION 4.3 • n=131 Participants • Data not collected for 4 healthy participants
|
66.4 inches
STANDARD_DEVIATION 4.2 • n=190 Participants • Data not collected for 4 healthy participants
|
|
Body Mass Index
|
28.7 lbs/(in^2)*703
STANDARD_DEVIATION 7.3 • n=59 Participants • Data not collected for 4 healthy participants
|
28.2 lbs/(in^2)*703
STANDARD_DEVIATION 5.7 • n=131 Participants • Data not collected for 4 healthy participants
|
28.4 lbs/(in^2)*703
STANDARD_DEVIATION 6.3 • n=190 Participants • Data not collected for 4 healthy participants
|
|
Medical History
Chronic Obstructive Pulmonary Disease (COPD)
|
3 participants
n=63 Participants
|
24 participants
n=131 Participants
|
27 participants
n=194 Participants
|
|
Medical History
Type 1 diabetes
|
2 participants
n=63 Participants
|
3 participants
n=131 Participants
|
5 participants
n=194 Participants
|
|
Medical History
Type 2 diabetes
|
18 participants
n=63 Participants
|
65 participants
n=131 Participants
|
83 participants
n=194 Participants
|
|
Medical History
Clots or deep vein thrombosis (DVT)
|
0 participants
n=63 Participants
|
7 participants
n=131 Participants
|
7 participants
n=194 Participants
|
|
Medical History
Venous Disease
|
12 participants
n=63 Participants
|
35 participants
n=131 Participants
|
47 participants
n=194 Participants
|
|
Wound History
|
4 Participants
n=63 Participants
|
14 Participants
n=131 Participants
|
18 Participants
n=194 Participants
|
|
Smoking Status
Current
|
5 Participants
n=63 Participants
|
31 Participants
n=131 Participants
|
36 Participants
n=194 Participants
|
|
Smoking Status
Previous
|
24 Participants
n=63 Participants
|
67 Participants
n=131 Participants
|
91 Participants
n=194 Participants
|
|
Smoking Status
Never
|
34 Participants
n=63 Participants
|
33 Participants
n=131 Participants
|
67 Participants
n=194 Participants
|
PRIMARY outcome
Timeframe: 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.
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).
Outcome measures
| Measure |
Peripheral Artery Disease (1) vs Not PAD
n=218 limbs
All patients were assigned PAD (1) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 with exhibition of at least mild claudication (Rutherford Category\>0) and 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.
Not PAD are patients that did not meet the definition above.
|
Peripheral Artery Disease (2) vs Not PAD
n=218 limbs
All patients were assigned PAD (2) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 without exhibition of symptoms and 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.
Not PAD are patients that did not meet the definition above.
|
Critical Limb Ischemia (CLI) vs Not CLI
n=220 limbs
All patients were assigned CLI based on exhibition of chronic rest pain and active wounds, verified by TBI\<0.3. CLI cohort 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.
Not CLI are patients that did not meet the definition above.
|
|---|---|---|---|
|
Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI
Area Under the Curve (3 months)
|
0.58 probability
Interval 0.45 to 0.71
|
0.67 probability
Interval 0.54 to 0.8
|
0.95 probability
Interval 0.86 to 1.0
|
|
Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI
Sensitivity (Initial)
|
0.80 probability
Interval 0.73 to 0.87
|
0.78 probability
Interval 0.71 to 0.85
|
0.82 probability
Interval 0.66 to 0.98
|
|
Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI
Specificity (Initial)
|
0.78 probability
Interval 0.7 to 0.87
|
0.86 probability
Interval 0.78 to 0.94
|
0.78 probability
Interval 0.72 to 0.84
|
|
Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI
Area Under the Curve (Initial)
|
0.84 probability
Interval 0.78 to 0.89
|
0.87 probability
Interval 0.82 to 0.92
|
0.86 probability
Interval 0.8 to 0.93
|
|
Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI
Sensitivity (3 months)
|
0.52 probability
Interval 0.38 to 0.67
|
0.57 probability
Interval 0.44 to 0.71
|
1.00 probability
Interval 1.0 to 1.0
|
|
Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI
Specificity (3 months)
|
0.63 probability
Interval 0.46 to 0.81
|
0.77 probability
Interval 0.6 to 0.95
|
0.91 probability
Interval 0.84 to 0.97
|
|
Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI
Sensitivity (6 months)
|
0.74 probability
Interval 0.62 to 0.86
|
0.73 probability
Interval 0.62 to 0.84
|
1.00 probability
Interval 1.0 to 1.0
|
|
Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI
Specificity (6 months)
|
0.58 probability
Interval 0.41 to 0.74
|
0.67 probability
Interval 0.48 to 0.86
|
0.59 probability
Interval 0.48 to 0.69
|
|
Sensitivity and Specificity of FlowMet-R for Diagnosis of PAD and CLI
Area Under the Curve (6 months)
|
0.62 probability
Interval 0.49 to 0.74
|
0.67 probability
Interval 0.54 to 0.79
|
0.79 probability
Interval 0.39 to 1.0
|
SECONDARY outcome
Timeframe: Within three and six months following initial visitPopulation: PAD (1), PAD (2) and CLI participants who underwent vascular intervention following their 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).
Outcome measures
| Measure |
Peripheral Artery Disease (1) vs Not PAD
n=80 limbs
All patients were assigned PAD (1) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 with exhibition of at least mild claudication (Rutherford Category\>0) and 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.
Not PAD are patients that did not meet the definition above.
|
Peripheral Artery Disease (2) vs Not PAD
n=92 limbs
All patients were assigned PAD (2) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 without exhibition of symptoms and 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.
Not PAD are patients that did not meet the definition above.
|
Critical Limb Ischemia (CLI) vs Not CLI
All patients were assigned CLI based on exhibition of chronic rest pain and active wounds, verified by TBI\<0.3. CLI cohort 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.
Not CLI are patients that did not meet the definition above.
|
|---|---|---|---|
|
Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention
Sensitivity
|
0.60 probability
Interval 0.3 to 0.9
|
0.59 probability
Interval 0.35 to 0.82
|
—
|
|
Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention
Specificity
|
0.49 probability
Interval 0.37 to 0.6
|
0.56 probability
Interval 0.45 to 0.67
|
—
|
|
Sensitivity and Specificity of FlowMet-R for Prognosis of Requiring a Peripheral Vascular Intervention
Area Under the Curve (AUC)
|
0.52 probability
Interval 0.32 to 0.71
|
0.54 probability
Interval 0.39 to 0.69
|
—
|
SECONDARY outcome
Timeframe: Initial visitPopulation: All PAD participants with significant stenosis, defined by greater than 50%, in at least one peripheral artery and generated using FlowMet-R measurement data.
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).
Outcome measures
| Measure |
Peripheral Artery Disease (1) vs Not PAD
n=134 limbs
All patients were assigned PAD (1) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 with exhibition of at least mild claudication (Rutherford Category\>0) and 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.
Not PAD are patients that did not meet the definition above.
|
Peripheral Artery Disease (2) vs Not PAD
All patients were assigned PAD (2) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 without exhibition of symptoms and 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.
Not PAD are patients that did not meet the definition above.
|
Critical Limb Ischemia (CLI) vs Not CLI
All patients were assigned CLI based on exhibition of chronic rest pain and active wounds, verified by TBI\<0.3. CLI cohort 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.
Not CLI are patients that did not meet the definition above.
|
|---|---|---|---|
|
Sensitivity, Specificity and Area Under the Curve (AUC) of FlowMet-R in Diagnosing Significant Stenosis
Area Under the Curve (AUC)
|
0.63 probability
Interval 0.53 to 0.73
|
—
|
—
|
|
Sensitivity, Specificity and Area Under the Curve (AUC) of FlowMet-R in Diagnosing Significant Stenosis
Sensitivity
|
0.61 probability
Interval 0.51 to 0.72
|
—
|
—
|
|
Sensitivity, Specificity and Area Under the Curve (AUC) of FlowMet-R in Diagnosing Significant Stenosis
Specificity
|
0.61 probability
Interval 0.48 to 0.75
|
—
|
—
|
SECONDARY outcome
Timeframe: Initial visitPopulation: 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.
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.
Outcome measures
| Measure |
Peripheral Artery Disease (1) vs Not PAD
n=134 limbs
All patients were assigned PAD (1) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 with exhibition of at least mild claudication (Rutherford Category\>0) and 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.
Not PAD are patients that did not meet the definition above.
|
Peripheral Artery Disease (2) vs Not PAD
All patients were assigned PAD (2) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 without exhibition of symptoms and 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.
Not PAD are patients that did not meet the definition above.
|
Critical Limb Ischemia (CLI) vs Not CLI
All patients were assigned CLI based on exhibition of chronic rest pain and active wounds, verified by TBI\<0.3. CLI cohort 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.
Not CLI are patients that did not meet the definition above.
|
|---|---|---|---|
|
Stenosis Percentage
|
67.9 percentage of stenosis
Standard Deviation 32.5
|
—
|
—
|
SECONDARY outcome
Timeframe: 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.
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.
Outcome measures
| Measure |
Peripheral Artery Disease (1) vs Not PAD
n=75 limbs
All patients were assigned PAD (1) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 with exhibition of at least mild claudication (Rutherford Category\>0) and 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.
Not PAD are patients that did not meet the definition above.
|
Peripheral Artery Disease (2) vs Not PAD
n=84 limbs
All patients were assigned PAD (2) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 without exhibition of symptoms and 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.
Not PAD are patients that did not meet the definition above.
|
Critical Limb Ischemia (CLI) vs Not CLI
n=57 limbs
All patients were assigned CLI based on exhibition of chronic rest pain and active wounds, verified by TBI\<0.3. CLI cohort 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.
Not CLI are patients that did not meet the definition above.
|
|---|---|---|---|
|
Changes in Ankle Brachial Index (ABI)
|
0.09 mmHg / mmHg
Standard Deviation 0.23
|
0.08 mmHg / mmHg
Standard Deviation 0.31
|
0.03 mmHg / mmHg
Standard Deviation 0.22
|
SECONDARY outcome
Timeframe: Within three and six months following initial visit.Population: Limbs of participants with TBI measured at 0, 3, and 6 months.
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.
Outcome measures
| Measure |
Peripheral Artery Disease (1) vs Not PAD
n=76 limbs
All patients were assigned PAD (1) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 with exhibition of at least mild claudication (Rutherford Category\>0) and 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.
Not PAD are patients that did not meet the definition above.
|
Peripheral Artery Disease (2) vs Not PAD
n=86 limbs
All patients were assigned PAD (2) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 without exhibition of symptoms and 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.
Not PAD are patients that did not meet the definition above.
|
Critical Limb Ischemia (CLI) vs Not CLI
n=58 limbs
All patients were assigned CLI based on exhibition of chronic rest pain and active wounds, verified by TBI\<0.3. CLI cohort 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.
Not CLI are patients that did not meet the definition above.
|
|---|---|---|---|
|
Changes in Toe Brachial Index (TBI)
|
0.08 mmHg / mmHg
Standard Deviation 0.24
|
0.10 mmHg / mmHg
Standard Deviation 0.25
|
0.02 mmHg / mmHg
Standard Deviation 0.18
|
SECONDARY outcome
Timeframe: 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.
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.
Outcome measures
| Measure |
Peripheral Artery Disease (1) vs Not PAD
n=76 limbs
All patients were assigned PAD (1) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 with exhibition of at least mild claudication (Rutherford Category\>0) and 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.
Not PAD are patients that did not meet the definition above.
|
Peripheral Artery Disease (2) vs Not PAD
n=84 limbs
All patients were assigned PAD (2) by the following criteria: ABI≤0.9 or ABI\>1.4 and secondary verification of TBI≤0.7 without exhibition of symptoms and 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.
Not PAD are patients that did not meet the definition above.
|
Critical Limb Ischemia (CLI) vs Not CLI
n=58 limbs
All patients were assigned CLI based on exhibition of chronic rest pain and active wounds, verified by TBI\<0.3. CLI cohort 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.
Not CLI are patients that did not meet the definition above.
|
|---|---|---|---|
|
Changes in Rutherford Classification
|
-0.39 units on a scale
Standard Deviation 1.4
|
-0.62 units on a scale
Standard Deviation 1.5
|
-0.26 units on a scale
Standard Deviation 1.2
|
Adverse Events
Healthy
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Peripheral Artery Disease
Serious events: 6 serious events
Other events: 2 other events
Deaths: 4 deaths
Serious adverse events
| Measure |
Healthy
n=52 participants at risk
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.
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.
|
Peripheral Artery Disease
n=143 participants at risk
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 cohort 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.
|
|---|---|---|
|
Surgical and medical procedures
Amputation
|
0.00%
0/52 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
2.1%
3/143 • Number of events 3 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
|
Surgical and medical procedures
Femoral Artery Bypass
|
0.00%
0/52 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
0.70%
1/143 • Number of events 1 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
|
Surgical and medical procedures
Femorofemoral Bypass
|
0.00%
0/52 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
0.70%
1/143 • Number of events 1 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
|
Skin and subcutaneous tissue disorders
Non-Healing Left Leg Ulcer
|
0.00%
0/52 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
0.70%
1/143 • Number of events 1 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
|
Nervous system disorders
Cerebrovascular Accident
|
0.00%
0/52 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
0.70%
1/143 • Number of events 1 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
Other adverse events
| Measure |
Healthy
n=52 participants at risk
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.
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.
|
Peripheral Artery Disease
n=143 participants at risk
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 cohort 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.
|
|---|---|---|
|
Injury, poisoning and procedural complications
Pain during FlowMet-R Assessment
|
0.00%
0/52 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
0.70%
1/143 • Number of events 1 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
|
Vascular disorders
Hematoma
|
0.00%
0/52 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
0.70%
1/143 • Number of events 1 • Adverse events were collected from the baseline assessment visit throughout 6-month follow-up.
Investigators submitted device-related or suspected device-related AE or SAE to the sponsor and IRB within 5 business days after awareness. Sites were required to only include AEs that were reasonably associated with use of the FlowMet-R device. Investigators classified whether an AE was considered serious, non-serious and device related. All SAEs and AEs collected as part of the study are reported, including device- \& non-device related events. All deaths reported on the Exit form are included.
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place