18 Aug LIBERTY 360° PAD Study Reveals That ‘Watchful Waiting’ in Rutherford Class 2-3 and ‘Primary Amputation’ in Rutherford Class 6 May Not Be Necessary
MedicalResearch.com Interview with:
George Adams, M.D., M.H.S., F.A.C.C., F.S.C.A.I.
Director of Cardiovascular and Peripheral Vascular Research
Raleigh, North Carolina
Summary: The early findings of a novel all-comers PAD study (LIBERTY 360°) suggest that ‘watchful waiting’ in Rutherford class 2-3 and ‘primary amputation’ in Rutherford class 6 may not be necessary. Peripheral vascular intervention can be successful in these patient populations as well.
MedicalResearch.com: What is the background for this study?
Response: Approximately 18 million Americans have peripheral artery disease (PAD), and 2 million of these patients suffer from critical limb ischemia (CLI)1,2, the end stage of PAD3. CLI is highly prevalent in older patients with diabetes and/or end-stage renal disease4, and is associated with high risk of amputation and mortality5. Briefly, the LIBERTY 360° study6 is a prospective, observational, multi-center study with liberal inclusion criteria and few exclusions, meant to evaluate procedural and long-term clinical and economic outcomes of endovascular device interventions in patients with symptomatic lower extremity PAD, including CLI. The study included any FDA-approved technology to treat claudication and CLI. Four core laboratories were utilized for independent analysis.
MedicalResearch.com: What are the main findings?
Response: The LIBERTY 360° study enrolled nearly 1,200 patients across 51 sites in the US: 500 patients in the “Claudicant Rutherford 2-3 (R2-3)” Arm; 589 in the “CLI Rutherford 4-5 (R4-5)” Arm; and 100 in the “CLI Rutherford 6 (R6)”. As presented at AMP 2016, procedural complications rarely (0.8% to 2%) resulted in post-procedural hospitalization in all Rutherford classes and 78% of R6 subjects were discharged to their homes. Quality of life also improved from baseline across all Rutherford classes. At 30 days, the rate of freedom from major adverse events (MAE) was 99% in R2-3, 95.7% in R4-5 and 90.7% in R6.
MedicalResearch.com: What should readers take away from your report?
Response: Early findings (30-day results) in this novel, all-comers PAD study suggest that ‘watchful waiting’ in Rutherford 2-3 and ‘primary amputation’ in Rutherford-6 may not be necessary. Percutaneous vascular interventions can be successful in these patient populations as well.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Response: Ultimately, the knowledge gained from the LIBERTY 360° study may inform future PAD clinical trials, provide data to help physicians choose the best therapy for patients, and advance the treatment of PAD. Future well-designed and executed randomized controlled trials that track clinically relevant outcomes, including the cost of the endovascular treatments and long-term outcomes, will enable physicians to determine the optimal therapies for their patients with PAD.
- Yost M. Critical limb ischemia. The Sage Group; 2010.
- Schiavetta A, Maione C, Botti C, Marino G, Lillo S, Garrone A, Lanza L, Pagliari S, Silvestroni A, Signoriello G, Sica V, Cobellis G. A phase II trial of autologous transplantation of bone marrow stem cells for critical limb ischemia: results of the Naples and Pietra Ligure Evaluation of Stem Cells study. Stem Cells Transl Med 2012;1:572–578.
- Varu VN, Hogg ME, Kibbe MR. Critical limb ischemia. J Vasc Surg 2010;51:230–241.
- Eggers PW, Gohdes D, Pugh J. Nontraumatic lower extremity amputations in the Medicare end-stage renal disease population. Kidney Int 1999;56:1524–1533.
- Abu Dabrh AM, Steffen MW, Undavalli C, Asi N, Wang Z, Elamin MB, Conte MS, Murad MH. The natural history of untreated severe or critical limb ischemia. J Vasc Surg 2015;62:1642–1651.e3.
- Adams GL, Mustapha J, Gray W, Hargus NJ, Martinsen BJ, Ansel G, Jaff MR. The LIBERTY study: Design of a prospective, observational, multicenter trial to evaluate the acute and long-term clinical and economic outcomes of real-world endovascular device interventions in treating peripheral artery disease. Am Heart J 2016;174:14–21.
Adams GL, et al. LIBERTY 360° Study Procedural and 30-day Outcomes of Endovascular Device Interventions in Patients with Symptomatic Lower Extremity Peripheral Artery Disease Presented at: AMP: The Amputation Prevention Symposium; Aug. 10-13, 2016; Chicago.
Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.
Disclosure: The study was funded by Cardiovascular Systems Inc. Adams reports financial ties with Abbott Vascular, Asahi, Bard, Boston Scientific, Cardiovascular Systems Inc., CloSys, Cook Medical, Cordis, Daiichi Sankyo, Lake Region Medical, Medtronic, Penumbra, Spectranetics, Terumo and Volcano.