The study is a randomised comparison of recanalisation of chronic occluded coronary arteries with implantation of Sirolimus eluting stents and medical therapy. Myocardial function and scar-size are determinated by using magnetic resonance imaging. The study hypothesis is the superiority of medical therapy over revascularisation.

In the REVASC-study recovery of left ventricular function after recanalization of chronic total coronary occlusions (CTO) and implantation of sirolimus-eluting stents will be examined and compared to medical treatment. Extent of the scar, viable myocardium in the infarct zone and regional left ventricular function will be assessed by cardiac magnetic resonance. Patients with regional systolic left ventricular dysfunction of any degree in the supply territory of the CTO vessel will be randomized to either recanalization of the occluded coronary artery or to conservative therapy. It is of interest whether CTO patients will have an improvement in left ventricular function after late coronary reopening, regarding the high technical demands and costs of CTO recanalization.

Inclusion Criteria:

• chronic total occlusion with thrombolysis in myocardial infarction (TIMI) 0 flow (or distal capillary reflow) of a native coronary artery with an estimated reference vessel diameter of 2.5 to 4.0 mm
• chronic total occlusion has more than 4 weeks duration
• the target vessel has not previously been treated with percutaneous coronary intervention
• the target vessel must be feasible for stent implantation
• patient has stable or unstable angina pectoris or a positive functional study for ischemia
• patient must be 18 years of age or older
• female subjects of childbearing age must have a negative pregnancy test within 7 days before procedure
• patient has been informed of the nature of the study and agrees to its
• provisions ans has written informed consent as approved by the Ethics Committee
• patient complies with all required post-procedure follow-up

Exclusion Criteria:

• a documented left ventricular function < 30%
• patient has a acute myocardial infarction (>3x normal creatine kinase (CK with presence of CK-MB) within 72 hours preceding the index procedure and CK has not returned to normal limits at the time of the procedure
• patients with known hypersensitivity or contraindication to aspirin, heparin, clopidogrel, stainless steel or contrast media that cannot be adequately been pre-medicated
• patient has a platelet count of < 100000 cells/mm3 or > 700000 cells/m3, a white blood cell count of < 3000 cells/mm3 or documented or suspected liver disease
• patient has a history of bleeding diathesis or coagulopathy
• patient has suffered a cerebrovascular accident or transient ischemic attack within the past 6 months
• active peptic ulcer or upper gastrointestinal bleeding within the prior 6 months
• patients has a co-morbidity (i.e. cancer or congestive heart failure) that may cause the patient to be non-compliant with the protocol, or is associated with limited life-expectancy (less than 2 years)
• the target vessel contains intraluminal thrombus
• the target vessel or lesson shows angiographic evidence of severe calcification
• patient has contraindications to magnetic resonance imaging