COAST: Next-generation orbital atherectomy system tested in patients with severely calcified lesions

ORLANDO, Fla. — A next-generation orbital atherectomy system was used to treat severely calcified coronary lesions in the COAST study.

The investigational device (Diamondback 360 Micro Crown, Cardiovascular Systems Inc.) was designed to address tight lesions with distal sanding while allowing continuous blood flow while the device orbits, Richard A. Shlofmitz, MD, from St. Francis Hospital – The Heart Center, Roslyn, New York, said during a presentation at the Society for Cardiovascular Angiography and Interventions Scientific Sessions.

Richard A. Shlofmitz

Shlofmitz reported the 30-day results of an Investigational Device Exemption study of 100 patients (74 from the United States, 26 from Japan; mean age, 71 years; 71% men) with de novo severely calcified coronary lesions.

The primary safety endpoint was MACE, defined as MI, cardiac death and target vessel revascularization, at 30 days. The primary efficacy endpoint was procedural success, defined as stent delivery with residual stenosis < 50% and no in-hospital MACE.

The rate of severe angiographic complications was 7% (U.S. cohort, 9.5%; Japan cohort, 0%), according to Shlofmitz.

Freedom from 30-day MACE was 85% (95% CI, 78-92), but most of the events were non-Q-wave MIs, which are usually not clinically relevant, he said. The rates of the components of MACE were 1% cardiac death, 1% TVR and 14% MI (2% Q-wave MI, 12% non Q-wave MI).

The procedural success rate was 85% (95% CI, 76.5-91.4), with 99% successful stent delivery, 99% residual stenosis < 50% and 14% in-hospital MACE, Shlofmitz said. For both primary outcomes, rates were similar between the U.S. and Japan cohorts.

By comparison, the ORBIT II trial of a current-generation orbital atherectomy system (Diamondback 360 Classic Crown, Cardiovascular Systems Inc.) in patients with severely calcified coronary lesions had a 89.6% rate of freedom from MACE at 30 days and a 88.9% rate of procedural success, he said.

The rates of clinically relevant MI according to the SCAI definition were 1% in COAST and 2% in ORBIT II, he said.

“Adequate modification of calcium is very important to getting success in atherectomy,” Shlofmitz said. “This is a technology that’s addressing a very complex problem.” – by Erik Swain

Reference:

Shlofmitz RA, et al. Featured Clinical Research – Part 1. Presented at: Society for Cardiovascular Angiography and Interventions Scientific Sessions; May 4-7, 2016; Orlando, Fla.

Disclosure: Shlofmitz reports consulting for Cardiovascular Systems Inc.