CSI Releases 30-Day Results From Liberty 360° Study

August 11, 2016—Cardiovascular Systems, Inc. (CSI) announced that procedural and 30-day results from its LIBERTY 360° study were released in a late-breaking presentation at the 2016 Amputation Prevention Symposium (AMP) in Chicago, Illinois. George Adams, MD, Director of Cardiovascular and Peripheral Vascular Research at Rex Hospital in Raleigh, North Carolina, presented the 30-day results highlighting the freedom from major adverse events (MAE). 

LIBERTY 360° is a prospective observational multicenter 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 ischemia (CLI). 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 enrollment of 1,204 patients across 51 sites in the United States 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 to 3 patients, 589 Rutherford class 4 to 5 patients, and 100 Rutherford class 6 patients, those with the most severe form of PAD.

According to CSI, the study shows that peripheral interventions can be used successfully across all Rutherford classes, including the most challenging Rutherford class 6. 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 to 5 and > 60% of Rutherford class 6 interventions.

The LIBERTY 30-day outcomes (Rutherford classes 2–3, 4–5, and 6, respectively) showed freedom from MAE (99%, 95.7%, 90.7%), major amputation (100%, 98.8%, 95.8%), target vessel revascularization (99.4%, 96.9%, 97.9%), and death (99.6%, 99.7%, 95.9%). Quality of life also improved from baseline across all Rutherford classes.

In the company’s press release, Dr. Adams commented, “The results from the LIBERTY 360° study will provide us with valuable information about the clinical and economic outcomes of atherectomy in PAD patients. 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 MAE 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.”

LIBERTY investigator Jihad Mustapha, MD, of Metro Health Hospital in Grand Rapids, Michigan, added, “Procedural complications rarely resulted in postprocedural hospitalization in all Rutherford classes and, impressively, 78% of Rutherford class 6 subjects were discharged to their homes.” Dr. Mustapha concluded, “Early findings in this novel, all-comers PAD study suggest that ‘watchful waiting’ in Rutherford class 2 to 3 and ‘primary amputation’ in Rutherford class 6 may not be necessary. Percutaneous vascular interventions can be successful in these patient populations as well.”