Coronary Artery Stent Evaluation With 320-slice Computed Tomography - The CArS 320 Study

Inclusion Criteria: * Suspected coronary artery in-stent restenoses based on clinical findings or findings on other noninvasive imaging tests and planned coronary angiography within the next 14 days. * Able to understand and willing to sign the Informed CF. Exclusion Criteria: * Creatinine of above 2.0 mg/dl * Age below 40 years * Women of child bearing potential (no hysterectomy, no menopause, or menopause since less than 12 months) must demonstrate a negative pregnancy test performed within 24 hours before CT. * Resting heart rate above 70 beats per minute and contraindications to beta blockers (e.g. moderate to severe bronchospastic disease, asthma) * Atrial fibrillation, uncontrolled tachycardia, A-V block II or III degree or other non-sinus rhythms * Inability to hold the breath for 10 seconds * Hypotension \< 80 mmHg systolic * Unstable angina pectoris, acute myocardial infarction \< 48h * Continuous therapy with Dipyridamol * Severe aortic stenosis