Liberty 360 2-Year Data


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).

PAD Prognosis

  • For intermittent claudication (IC) patients, over a 5-year period, significant deterioration appears in
    20% of cases, of whom 2/3 with worsening claudication and 1/3 with Critical Limb Ischemia (CLI).
    For CLI patients, after 1-year, mortality is 20%, amputations are needed in 30%, while 45% are
    alive with both legs intact.1

Study Design

  • The LIBERTY study includes any FDA-approved technology to treat claudication and 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.

Key Takeaways

  • The findings in this novel, all-comers, 1,200-patient PAD study demonstrated high freedom from
    major amputation at 2 years and in an OAS sub-analysis despite complex demographics.
  • Freedom from 2-year target vessel revascularization (TVR)/target lesion revascularization (TLR)
    rates are similar in RC4-5 and RC6.
  • Significant improvement through 2 years in: Rutherford Class (RC) in all groups; Patient reported
    quality of life in all groups; Number of wounds in RC4-5 and RC6.
  • 2-year MAE predictor model indicates that many traditional predictors are significant in an
    unadjusted model yet when accounting for potential covariates, those associated with disease
    progression and previous treatments were most strongly correlated with 2-year MAE.
  • Peripheral vascular intervention (PVI) is a reasonable treatment option for RC2-3 and RC4-5.
  • Primary amputation may not be necessary in RC6—PVI can be successful in this patient
    population, as evidenced at 2 years by high freedom from major amputation (79.8%) and
    improvement in QoL and RC.
15-Jun-2018 Data
1. Olinic Dm, et al. Int Angiol. 2018;37:327-334.

Total Outcomes Through 2 Years by Rutherford Class

Despite complex demographics (e.g. history of lower extremity PVI, history of myocardial infarction (MI), CTOs, lesion length) in this
real-world study, there was high freedom from (FF) major amputation at 2 years in RC2-3 (99.1%), RC4-5 (94.5%), and RC6 (79.8%) and similar freedom from 2-Year TVR/TLR rates in RC4-5 (67.8%) and RC6 (65.7%).

FF MAE: RC2-3 74.7% RC4-5 65.6% RC6 50.9%

Patient Population

Enrollment and 2-Year Follow-up

*Due to site closure and lack of PI signature, baseline and procedure data from 15 subjects were excluded. Rutherford 2, N=97; Rutherford 3, N=403; Rutherford 4, N=285; Rutherford 5, N=304. Core Lab reported lesions.

Key Liberty Lesion Characteristics

High number of chronic total occlusions (CTOs) and below-the-knee (BTK) lesions treated across all groups.

N (%) or Mean SD as appropriate. Core Lab reported lesions (Lesions with reported values may be less than total number of lesions treated in each arm).

PROCEDURAL OUTCOMES

  • High procedural lesion treatment success across all RCs at 2 years (RC2–3: 84%, RC4–5: 76%, RC6: 69%).
  • 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% of the lesions treated, no severe angiographic complications in
    88% 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.
  • Improvement in outflow distal to the treated vessel(s) in 16% of RC2-3, 32% of RC4-5, and 39% of RC6
    post-PVI. Worsened outflow was seen in less than 2% of CLI patients post-PVI.

2-YEAR OUTCOMES

  • High freedom from major amputation at 2 years in RC2-3 (99.1%), RC4-5 (94.5%), and RC6 (79.8%) and
    in an OAS sub-analysis in RC2-3 (100%), RC4-5 (95.3%), and RC6 (88.5%) despite complex demographics.
  • Freedom from 2-year TVR/TLR rates are similar in RC4-5 (67.8%) and RC6 (65.7%).
  • Significant improvement through 2 years in:
    – Rutherford Class in all groups;
    – Patient reported quality of life in all groups;
    – Number of wounds in RC4-5 and RC6.
  • 2-year MAE predictor model indicates that many traditional predictors are significant in an unadjusted
    model, yet when accounting for potential covariates, those associated with disease progression and
    previous treatments were most strongly correlated with 2-year MAE.

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