Two-Year ORBIT II Results Presented for CSI's Diamondback 360 OAS Device

May 7, 2015—The Society for Cardiovascular Angiography and Interventions (SCAI) announced that late-breaking clinical trial data from ORBIT II were presented at the SCAI 2015 scientific sessions being held in May 6–9 in San Diego, California. After 2 years, patients with severely calcified plaque in the coronary arteries who were treated with Cardiovascular Systems Inc.'s Diamondback 360 orbital atherectomy system (OAS) before stenting continued to show positive results.

According to SCAI, ORBIT II included patients who are usually excluded from large clinical trials, such as patients on hemodialysis or with low left ventricular ejection fraction (< 25%). Also, in patients treated with percutaneous coronary intervention (PCI), calcified lesions may prevent the stent from fully expanding in the artery, and patients may need a repeat coronary intervention or coronary artery bypass graft surgery.

For the clinical trial, investigators enrolled 443 patients at 49 sites in the United States. The patients’ severely calcified lesions were treated with the Diamondback 360 OAS before stent placement. The device, which received US Food and Drug Administration approval in October 2013, has previously demonstrated favorable safety outcomes in hospital, at 30 days and at 1 year.The device’s eccentric crown creates an elliptical orbit in the artery to sand the calcified portion of the plaque into minuscule particles, noted the society.

The new 2-year follow-up data showed that 19.4% of patients experienced a major adverse cardiac event (MACE), including cardiac death (4.3%) and the need for a repeat procedure to open the target vessel (8.1%).

ORBIT II principal investigator Jeffrey Chambers, MD, commented in SCAI’s press release,  “ORBIT II includes some of the most high-risk PCI patients. We found that preparing the artery prior to stent placement with orbital atherectomy is associated with low complication rates and may allow many of these patients to avoid more invasive surgery.”  Dr. Chambers is Director of the Cardiac Catheterization Laboratory at Mercy Hospital in Minneapolis, Minnesota.

SCAI also noted that the study found similar rates of MACE in patients with and without diabetes, even though patients who have diabetes typically have higher rates of MACE after PCI than those who do not.

Additionally, a cost analysis presented by ORBIT II investigators found that OAS is a cost-effective treatment at 1 year with total cost savings projected to be up to $4,913. When the cost of the OAS device ($3,795) was taken into account, there was still a potential cost savings of up to $1,118, advised SCAI.