The purpose of the COAST clinical study data will be to utilize and to gain approval for commercializing the Micro Crown as part of the Coronary Orbital Atherectomy System (OAS).

This is a prospective, single-arm, multi-center, global study designed to evaluate performance of the Diamondback 360® Coronary Orbital Atherectomy System Micro Crown (OAS Micro Crown) in treating de novo, severely calcified coronary lesions.

Inclusion Criteria:

• Subjects must be 18 or older.
• Subjects must have a clinical indication for coronary intervention.
• CK and CK-MB must be less than or equal to the upper limit of lab normal value within 8 hours prior to the procedure.
• The target lesion must be a de novo coronary lesion that has not been previously treated with any interventional procedure.
• The target vessel must be a native coronary artery.
• The target vessel reference diameter must be >= 2.5mm and <= 4.0 mm.
• The lesion length must not exceed 40 mm.
• The target vessel must have a TIMI flow three (3) at baseline.
• The target lesion must have fluoroscopic, IVUS or OCT evidence of severe calcium deposit at the lesion site.
• The lesion must be crossable with the study guide wire.

Exclusion Criteria:

• Inability to understand the study requirements or has a history of non-compliance with medical advice.
• Unwilling to sign the COAST ICF.
• History of any cognitive or mental health status that would interfere with study participation.
• Currently enrolled in any other pre-approval investigational study.
• Female subjects who are pregnant or planning to become pregnant within the study period.
• Known hypersensitivity or contraindication to aspirin, heparin, ticlopidine or clopidogrel without adequate alternative medications.
• Known sensitivity to contrast media, which cannot be adequately pre-medicated.
• Diagnosed with chronic renal failure unless under hemodialysis, or has a serum creatinine level > 2.5 mg/dl.
• Experienced acute MI, STEMI or non-STEMI: CK-MB greater than the upper limit of lab normal value, within 30 days prior to index procedure.
• History of major cardiac intervention within 30 days.
• Evidence of heart failure
• History of a stroke or TIA within six (6) months.
• Active peptic ulcer or upper GI bleeding within six (6) months.
• History of bleeding diathesis or coagulopathy or intention to refuse blood transfusion, if one should become necessary.
• Concurrent medical condition with a life expectancy of < 12 months.
• History of immune deficiency.
• Uncontrolled insulin dependent diabetes.
• Evidence of active infections on the day of the index procedure.
• Subject has planned cardiovascular intervention within 60 days post index procedure.
• Subject is not an acceptable candidate for emergent CABG surgery.
• Subject with known allergy to atherectomy lubricant components such as soybean oil, egg yolk phospholipids, glycerin and sodium hydroxide.
• Subject with angiographically confirmed evidence of more than one (1) lesion requiring intervention, unless the treatment of the lesions is staged.
• Target lesion is located in a native vessel distal to anastomosis with a saphenous vein graft or LIMA/RIMA bypass.
• Target vessel has other lesions with greater than 50% diameter stenosis based on visual estimate or on-line QCA.
• Target vessel has angiographically visible or suspected thrombus.
• Target vessel has a stent from previous PCI.
• Target vessel appears to be or is excessively tortuous at baseline.
• Target lesion is an ostial location (within 5 mm of ostium) or an unprotected left main lesion.
• Target lesion is a bifurcation.
• Target lesion has a ≥ 1.5 mm side branch.
• Angiographic evidence of a dissection prior to initiation of OAD.

30 Days Post Procedure

Serious Adverse Events reported by sites and adjudicated by the Clinical Events Committee.