LIBERTY 360º | CSI360

LIBERTY 360º

Liberty360

LIBERTY is a prospective, observational, multi-center study to evaluate procedural and long-term clinical and economic outcomes of endovascular device interventions in patients with symptomatic lower extremity peripheral artery disease (PAD).

Key Takeaways

  • The findings in this novel, all-comers, 1,200 patient PAD study demonstrated high freedom from major amputation, target vessel revascularization (TVR), and death in all Rutherford Classes (RC) at 12 months
  • This data demonstrated that on average, PAD patients 1-year post peripheral vascular intervention (PVI) had positive changes in RC, number of wounds (RC4–6), and improved quality of life
  • RC6 subjects, who are often excluded from PVI studies, demonstrated high freedom from major amputation, positive changes in RC, and wound reduction, despite advanced disease state

 

Study Design

  • The LIBERTY study includes any FDA-approved technology to treat claudication and Critical Limb Ischemia (CLI)
  • Lesions studied were within or extending into 10 cm above the medial epicondyle to the digital arteries (distal 1/3 of the SFA and below)
  • 4 core laboratories were utilized for independent analysis
  • 1204 subjects were enrolled at 51 sites spanning a broad spectrum of sites of care including community hospitals, large teaching hospitals, VA centers, and office-based labs (OBLs)
  • 131 operators treated patients in LIBERTY; 37 individual operators treated RC6 patients
  • Endpoints include: Procedural and lesion success, Major Adverse Events (MAEs), Duplex ultrasound, Quality of Life (QoL), Six-minute walk test (6MWT), Economic analysis

Patient Population

Enrollment and 1-Year Follow-up LIBERTY 360 Orbital Atherectomy

 

LIBERTY Target Lesion Characteristics (Core Lab Reported)

 
 RC2-3RC4-5RC6
Target lesion location*
ATK only48.7% (292/599)26.8% (203/758)26.7% (39/146)
ATK and BTK13.2% (79/599)12.5% (95/758)12.3% (18/146)
BTK only38.1% (228/599)60.6% (459/758)60.3% (88/146)
Mean target lesion length87.7 ± 86.5mm (N=558)130.5 ± 117.7mm (N=715)106.0 ± 93.8mm (N=135)
Calcified59.6% (334/560)57.1% (407/713)59.7% (83/139)
Chronic total occlusion32.9% (194/589)44.1% (326/740)39.9% (57/143)

*Per protocol, lesions located within or extending into 10 cm above the medial epicondyle to the digital arteries.

 

 

Study Results

Liberty Total 12-month FF-MAE by RC | amCharts

Composite Freedom From Major Adverse Event (FF-MAE) and FF-event rates at 12-months by Rutherford Classification. MAE defined as major amputation of the target limb, target vessel revascularization (TVR) and death within 30 days of index procedure. Rates for overall population (RC2–3 (N=500), RC4–5 (N=589), RC6 (N=100)).

*Inclusive of all deaths after 30 days

 

Test Liberty OAS Sub-Analysis: Total 12-month FF-MAE by RC | amCharts

Sub-analysis of patients treated with OAS (RC2–3 (N=211), RC4–5 (N=226), RC6 (N=56)) Composite Freedom From Major Adverse Event (FF-MAE) and FF-event rates at 12-months by Rutherford Classification. MAE defined as major amputation of the target limb, target vessel revascularization (TVR) and death within 30 days of index procedure.

*Inclusive of all deaths after 30 days

 

  • An OAS sub-analysis demonstrated favorable freedom from MAEs (FF-MAE) at 12 months across all Rutherford classes
  • In a sub-analysis of patients treated with OAS and drug-coated balloon (DCB) there was a 95.2% freedom from MAE at 12 months (N=21)
Change in Rutherford Classification

In the LIBERTY study, RC4-5 and RC6 showed continued improvement from 30 days to 12 months, while RC2-3 maintained 30-day improvement at 12 months.

Liberty Mean Rutherford Classification | amCharts
Rutherford Classification
(Mean ± SD)
RC2-3RC4-5RC6
Baseline2.8 ± 0.44.5 ± 0.56.0 ± 0.0
Change to 30 Days-1.6 ± 1.2-1.4 ± 1.8-0.5 ± 1.3
Change to 6 Months-1.4 ± 1.2-2.2 ± 1.9-1.4 ± 2.3
Change to 1 Year-1.5 ± 1.3-2.6 ± 1.9-2.5 ± 2.6

 

VascuQoL

Patient-reported quality of life using the VascuQoL improved from baseline at 30-days across all RCs and was maintained at 12 months in RC2-3 and RC4-5. RC6 continued improvement through 12 months.

Liberty VascuQoL Total Score | amCharts
Vascular Quality of Life Questionnaire; a PAD-specific health-related quality of life instrument. Higher total score indicates better rating of health (total score includes: physical activity, symptom, pain, emotional, and social domains).
Target Wound Healing

RC4-5 and RC6 show continued improvement in number of wounds from 30 days to 12 months.

Liberty Mean Number of Wounds on Target Limb | amCharts
Number of Wounds on Target Limb
(Mean ± SD)
RC2-3RC4-5RC6
Baseline0.0 ± 0.20.8 ± 0.91.7 ± 1.1
Change to 30 Days0.0 ± 0.2-0.1 ± 0.6-0.3 ± 1.0
Change to Months0.0 ± 0.3-0.4 ± 0.9-0.9 ± 1.0
Change to 1 Year0.0 ± 0.2-0.5 ± 0.9-1.3 ± 1.1

 

 

Procedural Outcomes

  • High procedural lesion treatment success across all RCs (85.7% RC2–3; 80.2% RC4–5; 76.1% RC6)
  • One of the first procedural and lesion outcome datasets on RC6 patients. In this study, PVI in RC6 subjects resulted in <50% residual stenosis in 83.0% of the lesions treated, no angiographic complications in 89.0% of lesions
  • Procedural complications rarely (0.8%-2.0%) resulted in post-procedural hospitalization in all RCs and 78% of RC6 subjects were discharged to home
  • Number of runoff vessels increased post-PVI with significant improvement seen in RC4–5 and RC6 compared to RC2–3. Runoff was worsened post-PVI in less than 6% of patients

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