Heart Rate Control Before Cardiac Computed Tomography in Adults for the Evaluation of Coronary Artery Disease

Inclusion Criteria: * Individuals who are to undergo Cardiac CT * Sinus rhythm with heart rate \> 65 bpm on ECG * Competent patients who have given written informed consent Exclusion Criteria: * Age \> 80 years * Age \< 30 years * Heart rate \> 100 bpm * BMI \> 35 * Previous percutaneous coronary intervention (with or without stent) * Previous CABG * Known ischemic heart disease * Pacemaker * Acute coronary syndrome * Known allergy to beta-blockers * Known allergy to ivabradine * Known allergy to used radiographic contrast agents * Pregnant, including potentially pregnant, or breastfeeding (potentially pregnant patients will undergo pregnancy testing) * Heart failure with systolic left ventricular ejection fraction \< 45% * Reduced kidney function with estimated glomerular filtration rate (eGFR) \< 40 ml/min * Regular treatment with beta-blockers * Regular treatment with ivabradine * Regular treatment with non-dihydropyridine calcium antagonists (Verapamil and Diltiazem) * Regular treatment with Cordarone * Contraindications for beta-blockers or ivabradine: * Severe asthma * Severe COPD * Sick sinus syndrome * Sinoatrial block (1st degree AV block) * Advanced AV block (2nd or 3rd degree) * Hypotension (systolic blood pressure \< 110 mmHg) * Severe heart failure * Severe restrictive cardiomyopathy * Severe aortic stenosis * Severe circulatory disturbances * Severe metabolic conditions * Untreated pheochromocytoma * Concurrent treatment with potent inhibitors of CYP3A4 * Concurrent treatment with potent inhibitors of MAO inhibitors, * Concurrent treatment with potent inhibitors of CYP2D6 inhibitors * Concurrent treatment with potent inhibitors of intravenous calcium antagonists type I or III