Stenoses
Conditions
Keywords
Hemodialysis, Vascular Prosthesis, stenoses, grafts
Brief summary
This study compared the FLAIR™ Endovascular Stent Graft to balloon angioplasty in patients with stenoses at the venous anastomosis of a synthetic AV access graft.
Detailed description
A total of 227 patients were treated at 16 U.S. investigational sites to evaluate the safety and effectiveness of the FLAIR™ Endovascular Stent Graft. This study compared the FLAIR™ Endovascular Stent Graft to balloon angioplasty in patients with stenoses at the venous anastomosis of a synthetic AV access graft.
Interventions
Primary balloon angioplasty followed by placement of the FLAIR Endovascular Stent Graft
PROCEDUREPTA
Percutaneous Transluminal Angioplasty
Sponsors
C. R. Bard
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 90 Years
Healthy volunteers
No
Inclusion criteria
* Male or female patients between 18 to 90 years of age whose hemodialysis access was a synthetic AV access graft located in an arm. * Angiographic evidence of one or more stenoses, 7 cm or less in length and greater than or equal to 50%, at the graft-vein anastomosis of a synthetic AV access graft. The entire lesion must have been located within 7 cm of the anastomosis such that approximately 1 cm of the IMPRA/Bard Device must have extended into non-diseased vein and approximately 1 cm, but no more than 2 cm, of the IMPRA/Bard Device will be extended into non-diseased AV graft. * Clinical evidence of a hemodynamically significant stenosis. * Percutaneous endovascular therapy for the identified lesion was the best treatment choice in the opinion of the investigator. * Patients must have been able to understand and provide informed consent. * Patients whose synthetic AV access grafts had been implanted greater than 30 days and had undergone 1 or more successful hemodialysis sessions. * During primary balloon angioplasty, full expansion of an appropriately sized angioplasty balloon, in the operator's judgment, must have been achieved.
Exclusion criteria
* Concomitant disease (e.g., terminal cancer) or other medical condition that was likely to result in death of the patient within 6 months of the time of implantation. * Stenoses that had a corresponding thrombosis treated within 7 days. * The presence of a second lesion in the access circuit less than or equal to 3 cm from the edges of the primary lesion that was treated within 30 days or that was greater than or equal to 30%. Access circuit was defined as the area from the AV access graft arterial anastomosis to the superior vena cava-right atrial junction. * The presence of a second lesion in the access circuit greater than 3 cm from the edges of the primary lesion that was greater than or equal to 30%. Second lesions that were greater than or equal to 30% must have been treated prior to patient inclusion to reduce the percent stenosis to less than 30%. * Patients who were unwilling or unable to return for follow-up visits or patients with whom follow-up visits may have been unreliable. * Patients who had a stent placed at the target lesion site. * Patients with a blood coagulative disorder or sepsis. * Patients in which the IMPRA/Bard Device would have been required to cross an angle (between the inflow vein and synthetic AV access graft) that was greater than 90 degrees. * Patients in which the IMPRA/Bard Device would have been required to be deployed fully across the elbow joint, which is identified radiographically by a combination of the humeroulnar joint and the humeroradial joint. * Patients with a contraindication to the use of contrast media. * Patients whose AV access graft was infected. * Patients who were currently or were scheduled to enroll in other investigations that conflicted with follow-up testing or confounds data in this trial. * Procedural use of another investigational device. * Patients who were pregnant.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percent of Participants With Treatment Area Primary Patency (TAPP) | 6 month follow-up | TAPP was defined as patency (open to blood flow) after the study index procedure until reintervention in the treatment area (within 5 mm proximal or 5 mm distal to the study device or index balloon angioplasty treatment area), or thrombotic occlusion that involved the treatment area. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Percent of Participants With Successful Delivery of the Device | Index Procedure | The ability to successfully deliver the FLAIR™ Endovascular Stent Graft. Successful delivery is the ability to deliver and seat the implant in the intended location of a stenosed segment of the venous anastomosis region of a synthetic access graft. This attribute is only applicable to the FLAIR and FLAIR Roll-in arms. |
| Percent of Participants With Procedural Success | Index Procedure | Procedural Success was defined as anatomic success (\<30% residual stenosis) and at least one indicator of hemodynamic or clinical success |
| Percent of Participants With TAPP | 2 month Follow-Up | TAPP was defined as patency (open to blood flow) after the study index procedure until reintervention in the treatment area (within 5 mm proximal or 5 mm distal to the study device or index balloon angioplasty treatment area), or thrombotic occlusion that involved the treatment area. |
| Total Number of Adverse Events | 6 month Follow-Up | The safety endpoint was evaluated based on the incidence of adverse events observed within the same time interval. An adverse event was defined as any undesirable clinical occurrence in a patient that (a) is considered possibly or definietly device related by the investigator, (b) involves the access circuit (AV graft arterial anastomosis to the superior vena cava-right atrial junction) or the arm where the access circuit is located or (c) the investigator considers relevant to the objectives of this study. An adverse event could be mild, moderate or severe. |
| Percent of Participants With Access Circuit Assisted Primary Patency (ACAPP) | 6 month Follow-Up | ACAPP defined as patency (open to blood flow)following the index study procedure until access thrombosis or a surgical intervention that excludes the treated lesion from the access circuit. |
| Percent of Participants With Access Circuit Cumulative Patency (ACCP or Secondary Patency) | 6 month Follow-Up | ACCP defined as patency (open to blood flow) following the index study procedure until the access is surgically revised or abandoned because of the inability to treat the original lesion. Multiple treatments for occlusions to restore patency are compatible with ACCP. |
| Percent of Participants With Binary Restenosis | 6 month Follow-Up | Binary restenosis defined as lesions with greater than or equal to 50% diameter stenosis of the treatment area (calculated by a core lab). |
| Percent of Participants With Access Circuit Primary Patency (ACPP) | 6 month Follow-Up | ACCP defined as patency (open to blood flow) following the index study procedure until access thrombosis or an intervention of a lesion anywhere within the access circuit. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| FLAIR Primary PTA followed by placement of the FLAIR Endovascular Stent Graft | 97 |
| PTA Only Percutaneous Transluminal Angioplasty | 93 |
| FLAIR Roll-In Participants Primary PTA followed by placement of the FLAIR Endovascular Stent Graft. Roll-in participants were enrolled in the study for training purposes and were not randomized. | 37 |
| Total | 227 |
Baseline characteristics
| Characteristic | PTA Only | FLAIR Roll-In Participants | FLAIR | Total |
|---|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 43 Participants | 16 Participants | 45 Participants | 104 Participants |
| Age, Categorical Between 18 and 65 years | 50 Participants | 21 Participants | 52 Participants | 123 Participants |
| Age Continuous | 59.83 years STANDARD_DEVIATION 13.58 | 62.16 years STANDARD_DEVIATION 11.84 | 61.83 years STANDARD_DEVIATION 14.63 | 60.36 years STANDARD_DEVIATION 14.09 |
| Region of Enrollment United States | 93 participants | 37 participants | 97 participants | 227 participants |
| Sex: Female, Male Female | 57 Participants | 23 Participants | 64 Participants | 144 Participants |
| Sex: Female, Male Male | 36 Participants | 14 Participants | 33 Participants | 83 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — | — / — |
| other Total, other adverse events | 67 / 97 | 80 / 93 | 26 / 37 |
| serious Total, serious adverse events | 5 / 97 | 5 / 93 | 1 / 37 |
Outcome results
Primary
Percent of Participants With Treatment Area Primary Patency (TAPP)
TAPP was defined as patency (open to blood flow) after the study index procedure until reintervention in the treatment area (within 5 mm proximal or 5 mm distal to the study device or index balloon angioplasty treatment area), or thrombotic occlusion that involved the treatment area.
Time frame: 6 month follow-up
Population: If a participant was lost to follow-up prior to the follow-up interval window, then the participant's status was considered missing for that time point and was not included in the ITT analysis.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| FLAIR | Percent of Participants With Treatment Area Primary Patency (TAPP) | 51 Percentage of Participants |
| PTA Only | Percent of Participants With Treatment Area Primary Patency (TAPP) | 23 Percentage of Participants |
| FLAIR Roll-In Participants | Percent of Participants With Treatment Area Primary Patency (TAPP) | 60 Percentage of Participants |
p-value: <0.001Regression, Logistic
Secondary
Percent of Participants With Access Circuit Assisted Primary Patency (ACAPP)
ACAPP defined as patency (open to blood flow)following the index study procedure until access thrombosis or a surgical intervention that excludes the treated lesion from the access circuit.
Time frame: 6 month Follow-Up
Population: If a participant was lost to follow-up prior to the follow-up interval window, then the participant's status was considered missing for that time point and was not included in the ITT analysis.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| FLAIR | Percent of Participants With Access Circuit Assisted Primary Patency (ACAPP) | 66 Percentage of Participants |
| PTA Only | Percent of Participants With Access Circuit Assisted Primary Patency (ACAPP) | 74 Percentage of Participants |
| FLAIR Roll-In Participants | Percent of Participants With Access Circuit Assisted Primary Patency (ACAPP) | 66 Percentage of Participants |
Secondary
Percent of Participants With Access Circuit Cumulative Patency (ACCP or Secondary Patency)
ACCP defined as patency (open to blood flow) following the index study procedure until the access is surgically revised or abandoned because of the inability to treat the original lesion. Multiple treatments for occlusions to restore patency are compatible with ACCP.
Time frame: 6 month Follow-Up
Population: If a participant was lost to follow-up prior to the follow-up interval window, then the participant's status was considered missing for that time point and was not included in the ITT analysis.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| FLAIR | Percent of Participants With Access Circuit Cumulative Patency (ACCP or Secondary Patency) | 81 Percentage of Participants |
| PTA Only | Percent of Participants With Access Circuit Cumulative Patency (ACCP or Secondary Patency) | 86 Percentage of Participants |
| FLAIR Roll-In Participants | Percent of Participants With Access Circuit Cumulative Patency (ACCP or Secondary Patency) | 91 Percentage of Participants |
Secondary
Percent of Participants With Access Circuit Primary Patency (ACPP)
ACCP defined as patency (open to blood flow) following the index study procedure until access thrombosis or an intervention of a lesion anywhere within the access circuit.
Time frame: 6 month Follow-Up
Population: If a participant was lost to follow-up prior to the follow-up interval window, then the participant's status was considered missing for that time point and was not included in the ITT analysis.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| FLAIR | Percent of Participants With Access Circuit Primary Patency (ACPP) | 38 Percentage of Participants |
| PTA Only | Percent of Participants With Access Circuit Primary Patency (ACPP) | 20 Percentage of Participants |
| FLAIR Roll-In Participants | Percent of Participants With Access Circuit Primary Patency (ACPP) | 43 Percentage of Participants |
Secondary
Percent of Participants With Binary Restenosis
Binary restenosis defined as lesions with greater than or equal to 50% diameter stenosis of the treatment area (calculated by a core lab).
Time frame: 6 month Follow-Up
Population: If a participant was lost to follow-up prior to the follow-up interval window (or the core lab could not assess the angiogram), then the participant's status was considered missing for that time point and was not included in the ITT analysis.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| FLAIR | Percent of Participants With Binary Restenosis | 28 Percentage of Participants |
| PTA Only | Percent of Participants With Binary Restenosis | 78 Percentage of Participants |
| FLAIR Roll-In Participants | Percent of Participants With Binary Restenosis | 25 Percentage of Participants |
Secondary
Percent of Participants With Procedural Success
Procedural Success was defined as anatomic success (\<30% residual stenosis) and at least one indicator of hemodynamic or clinical success
Time frame: Index Procedure
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| FLAIR | Percent of Participants With Procedural Success | 94 Percentage of Participants |
| PTA Only | Percent of Participants With Procedural Success | 73 Percentage of Participants |
| FLAIR Roll-In Participants | Percent of Participants With Procedural Success | 95 Percentage of Participants |
Secondary
Percent of Participants With Successful Delivery of the Device
The ability to successfully deliver the FLAIR™ Endovascular Stent Graft. Successful delivery is the ability to deliver and seat the implant in the intended location of a stenosed segment of the venous anastomosis region of a synthetic access graft. This attribute is only applicable to the FLAIR and FLAIR Roll-in arms.
Time frame: Index Procedure
Population: The PTA Only group was not analyzed for this outcome measure because it is for successful delivery of the FLAIR study device (PTA Only is the control arm).
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| FLAIR | Percent of Participants With Successful Delivery of the Device | 99 Percentage of Participants |
| FLAIR Roll-In Participants | Percent of Participants With Successful Delivery of the Device | 100 Percentage of Participants |
Secondary
Percent of Participants With TAPP
TAPP was defined as patency (open to blood flow) after the study index procedure until reintervention in the treatment area (within 5 mm proximal or 5 mm distal to the study device or index balloon angioplasty treatment area), or thrombotic occlusion that involved the treatment area.
Time frame: 2 month Follow-Up
Population: If a participant was lost to follow-up prior to the follow-up interval window, then the participant's status was considered missing for that time point and was not included in the ITT analysis.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| FLAIR | Percent of Participants With TAPP | 80 Percentage of Participants |
| PTA Only | Percent of Participants With TAPP | 77 Percentage of Participants |
| FLAIR Roll-In Participants | Percent of Participants With TAPP | 89 Percentage of Participants |
Secondary
Total Number of Adverse Events
The safety endpoint was evaluated based on the incidence of adverse events observed within the same time interval. An adverse event was defined as any undesirable clinical occurrence in a patient that (a) is considered possibly or definietly device related by the investigator, (b) involves the access circuit (AV graft arterial anastomosis to the superior vena cava-right atrial junction) or the arm where the access circuit is located or (c) the investigator considers relevant to the objectives of this study. An adverse event could be mild, moderate or severe.
Time frame: 6 month Follow-Up
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| FLAIR | Total Number of Adverse Events | 106 total events |
| PTA Only | Total Number of Adverse Events | 106 total events |
| FLAIR Roll-In Participants | Total Number of Adverse Events | 33 total events |