Mass General - Division of Clinical Research

Participants must meet all of the following inclusion criteria: General inclusion criteria 1. At least 18 years of age at the time of consent 2. Experiencing clinical symptoms considered suggestive of ischemic heart disease (e.g., chest pain or discomfort, heart failure) or has evidence of myocardial ischemia (e.g., abnormal functional study) attributed to the CTO target vessel and is scheduled for clinically indicated percutaneous revascularization 3. Participant is eligible and consents to undergo PCI procedure 4. Acceptable candidate for percutaneous transluminal coronary angioplasty (PTCA), stenting, and emergency coronary artery bypass grafting (CABG) 5. Willing and able to sign a study Informed Consent Form (ICF) approved by a local or central Institutional Review Board (IRB) 6. Female participants of childbearing potential must have a negative pregnancy test per standard of care for PCI and be practicing contraception Angiographic inclusion criteria 7. A minimum of one de novo lesion with at least one target segment in a native coronary vessel meeting the definition of CTO (any non-acute total coronary occlusion fulfilling the angiographic characteristics consistent with high-grade native coronary stenosis (Thrombolysis in Myocardial Infarction (TIMI) score of 0 or 1) and estimated to be in duration of ≥ 3 months by clinical history and/or comparison with antecedent angiogram or electrocardiogram)

Participants must not meet any of the following exclusion criteria: General exclusion criteria 1. History of allergy to iodinated contrast that cannot be effectively managed medically 2. Evidence of acute myocardial infarction (MI) within 72 hours prior to the intended treatment defined as creatine kinase-muscle brain subunits (CK-MB) greater than 3 times the upper limit of normal (ULN) 3. Previous coronary interventional procedure of any kind within 30 days prior to the procedure 4. Any contraindication to cardiac catheterization or to any of the standard concomitant therapies used during routine cardiac catheterization and PCI (e.g., aspirin, clopidogrel, unfractionated heparin) 5. Target lesion requires treatment with another device, after successful crossing with a study device, other than PTCA devices prior to stent placement 6. Atherectomy procedure is planned for the target lesion 7. Known history of clinically significant abnormal laboratory findings ≤ 14 days prior to enrollment, including: - Neutropenia (<1000 neutrophils/mm^3) - Thrombocytopenia (<100,000 platelets/mm^3) - Aspartate aminotransferase (AST), alanine transaminase (ALT), alkaline phosphatase, or bilirubin > 1.5 × ULN - Serum creatinine >2.0 mg/dL 8. Evidence of current clinical instability including the following: - Sustained systolic blood pressure <100 mmHg or cardiogenic shock - Acute pulmonary edema or severe congestive heart failure (CHF). Severe CHF is defined as New York Heart Association (NYHA) Class IV - Suspected acute myocarditis, pericarditis, endocarditis, or cardiac tamponade - Suspected dissecting aortic aneurysm - Hemodynamically significant valvular heart disease, hypertrophic cardiomyopathy, restrictive cardiomyopathy, or congenital heart disease 9. History of stroke or transient ischemic attack within 6 months prior to procedure 10. Active peptic ulcer or upper gastrointestinal bleeding within 6 months prior to procedure 11. History of bleeding diathesis or coagulopathy or refusal of blood transfusions 12. Other pathology such as cancer, known mental illness, etc., which might, in the opinion of the Investigator, put the patient at risk or confound the results of the study 13. Unable or unwilling to comply with the protocol 14. Currently participating in an investigational drug or device study that has not completed the primary endpoint or that clinically interferes with the current study endpoints; or requires coronary angiography, intravascular ultrasound, or other coronary artery imaging procedures Angiographic exclusion criteria 15. Occlusion involves segment within previous stent ("in-stent occlusions") 16. Extensive lesion-related thrombus (TIMI thrombus grade 3 or 4) 17. Previous stenting (drug-eluting or bare metal) in the target vessel unless the following conditions are met: - It has been at least 9 months since the previous stenting - Target lesion is ≥15 mm away from the previously placed stent - Previously stented segment (stent plus 5 mm on either side) has no more than 40 percent diameter stenosis, based on visual estimate 18. Target vessel has other lesions proximal to the total occlusion identified with > 75 percent diameter stenosis based on visual estimate; exception: planned stenting of a lesion proximal to the target lesion that can be covered by a single stent (i.e., tandem lesions) is acceptable