Cardiovascular Systems releases 30-day results from LIBERTY 360° study

Diamondback 360
Diamondback 360

Cardiovascular Systems has released procedural and 30-day results from its LIBERTY 360° study in a late-breaking presentation at the 2016 Amputation Prevention Symposium (AMP; 10–13 August, Chicago, USA), showing high freedom from major adverse events across all Rutherford classes following endovascular interventions, including atherectomy.

LIBERTY 360° is a prospective, observational, multicentre clinical study evaluating the clinical and economic outcomes of a variety of endovascular interventions in patients with symptomatic peripheral artery disease (PAD), including critical limb ischaemia (CLI), the most severe form of PAD. The study includes all commercially available technologies, including CSI’s Diamondback 360 Peripheral Orbital Atherectomy System (OAS), to treat claudication and CLI. The company completed enrolment of 1,204 patients across 51 sites in the USA in February 2016.

The LIBERTY study includes patients with various levels of PAD ranked on the Rutherford classification scale. Included in the analysis are 500 Rutherford class 2/3 patients, 589 class 4/5 patients and 100 class 6 patients. The study shows that peripheral interventions can be used successfully across all Rutherford classes. The majority of devices used were balloons and atherectomy, and the Diamondback OAS was the most frequently used atherectomy device, representing approximately 45% of Rutherford classes 2–5 and over 60% of Rutherford class 6 interventions.

George Adams, director of Cardiovascular and Peripheral Vascular Research at Rex Hospital in Raleigh, USA, presented the 30-day results highlighting the freedom from major adverse events:

  • Freedom from major adverse events: R2/3=99%, R4/5=95.7% and R6=90.7%;
  • Freedom from major amputation: R2/3=100%, R4/5=98.8% and R6=95.8%;
  • Freedom from target vessel revascularisation: R2/3=99.4%, R4/5=96.9% and R6=97.9%;
  • Freedom from death: R2/3=99.6%, R4/5=99.7% and R6=95.9%.

Quality of life also improved from baseline across all Rutherford classes.

“The results from the LIBERTY 360° study will provide us with valuable information about the clinical and economic outcomes of atherectomy in PAD patients,” said Adams. “This is the first device study to specifically include patients with a prevalence of calcification across all Rutherford classes, particularly the most severe form of PAD, Rutherford class 6. Approximately 50% of lesions showed visible calcification on angiography, and we saw a freedom from major adverse events rate of 90.7% for Rutherford class 6 patients at 30 days. Future data will be essential in identifying the most effective ways to treat this challenging patient population.”

Mustapha said, “Procedural complications rarely resulted in post-procedural hospitalisation in all Rutherford classes and, impressively, 78% of Rutherford class 6 subjects were discharged to their homes.” He concluded, “Early findings in this novel, all-comers PAD study suggest that ‘watchful waiting’ in Rutherford class 2/3 and ‘primary amputation’ in Rutherford class 6 may not be necessary. Percutaneous vascular interventions can be successful in these patient populations as well.”