One-Year Results of the LIBERTY 360 Study: Evaluation of Acute and Midterm Clinical Outcomes of Peripheral Endovascular Device Interventions

Abstract

Purpose: To report the 1-year results of a multicenter study of peripheral artery disease (PAD) treatment with a variety of endovascular treatment strategies employed in routine practice.

Materials and methods: The LIBERTY trial ( ClinicalTrials.gov identifier NCT01855412) is a prospective, observational, core laboratory-assessed, multicenter study of endovascular device intervention in 1204 subjects (mean age 69.8±10.7 years; 770 men) stratified by Rutherford category (RC): claudicants (RC2,3; n=501) and critical limb ischemia (CLI) with no/minimal tissue loss (RC4,5; n=603) or significant tissue loss (RC6; n=100). Key outcomes included quality of life (QoL) measures (VascuQol and EuroQol) and freedom from major adverse events (MAE), defined as death (within 30 days), major amputation, and target vessel revascularization based on Kaplan-Meier analysis.

Results: Successful revascularization was beneficial, with RC improvement noted across all groups. Thirty-day freedom from MAE estimates were high across all groups: 99.2% in RC2,3, 96.1% in RC4,5, and 90.8% in RC6. At 12 months, the freedom from MAE was 82.6% in RC2,3, 73.2% in RC4,5, and 59.3% in RC6 patients. Estimates for freedom from major amputation at 12 months were 99.3%, 96.0%, and 81.7%, respectively. QoL scores improved significantly across all domains in all groups with 12-month VascuQol total scores of 5.3, 5.0, and 4.8 for RC2,3, RC4,5, and RC6, respectively.

Conclusion: The results indicate that peripheral endovascular intervention is a viable treatment option for RC2,3, RC4,5, and RC6 patients as evidenced by the high freedom from major amputation, as well as the improvement in QoL and the RC at 12 months. Furthermore, primary unplanned amputation is often not necessary in RC6.

Keywords: atherectomy; balloon angioplasty; claudication; critical limb ischemia; endovascular intervention; femoropopliteal segment; peripheral artery disease; quality of life; stent.

Conflict of interest statement

Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Jihad Mustapha receives consulting fees from Abbott Vascular, Bard Peripheral Vascular, Boston Scientific, Cagent Vascular, Cardiovascular Systems, Inc., Cook Medical, Medtronic, PQ Bypass, Spectranetics, and Terumo Medical. William Gray receives personal fees and institutional research support from Boston Scientific, Medtronic, and Spectranetics. Brad J. Martinsen and Ryan W. Bolduan are employees of Cardiovascular Systems, Inc. George L. Adams receives consultant fees from Bard Peripheral Vascular, Terumo Interventional Systems, Medtronic, Boston Scientific, Spectranetics, and Cardiovascular Systems, Inc. Gary Ansel receives consulting fees from Medtronic, Boston Scientific, Cook Medical, W.L. Gore & Associates, Abbott Vascular, CR Bard, and Phillips; he receives royalties from Cook Medical. Michael R. Jaff is a noncompensated advisor to Abbott Vascular, Boston Scientific, Medtronic Vascular, and Cordis, a Cardinal Health company; he is a consultant to Philips/Volcano, Silk Road Medical, Micell, Vactronix, and Venarum; and he has equity investments in PQ Bypass, Gemini, Vascular Therapies, Sano V, and Primacea.

Figures

Figure 1.

Change in the distribution of Rutherford categories (RC) through 12 months (mo). The dotted line tracks the means at each time point.

Figure 2.

Kaplan-Meier curves for (A) freedom from major adverse events, (B) death, (C) major target limb amputation, and (D) target vessel revascularization. The standard error did not exceed 10% for any group. MAE, major adverse events; RC, Rutherford category; TLR, target lesion revascularization; TVR, target vessel revascularization. The blue line represents the RC2,3 subgroup, the red line is the RC4,5 subgroup, and the green line denotes the RC6 subgroup.

Figure 3.

Change in mean Vascular Quality of Life scores through 12 months (mo). Higher scores indicate a better rating of health. BL, baseline; D, day; M, month.