The purpose of this study is to determine the diagnostic accuracy of MPICT for the detection of hemodynamically relevant coronary stenosis (as determined by invasive FFR) in patients with suspected or known CAD clinically referred for invasive angiography.

Rationale: Cardiac computed tomography (CT) provides accurate assessment of the coronary arteries and detects significant coronary stenosis with high diagnostic accuracy. However, the hemodynamic relevance of these stenotic lesion remains unclear, although highly relevant for clinical decision-making. Recent technical developments with third-generation dual-source CT allow to determine myocardial perfusion during hyperemia and thus for assessment of the hemodynamic relevance of coronary lesions using a dynamic acquisition mode. To date, there is only very limited evidence of the feasibility of this approach stemming from single-center studies with varying standards of reference.

Objective: To determine the diagnostic accuracy of MPICT for the detection of hemodynamically relevant coronary stenosis (as determined by invasive FFR) in patients with suspected or known CAD clinically referred for invasive angiography. In an optional sub-study the diagnostic accuracy of MPICT for the detection of myocardial perfusion defects as determined by cardiac magnetic resonance imaging (CMRI) will be investigated.

Study design: Observational cohort study with fractional flow reserve (FFR) during invasive angiography as the reference standard.

Study population: Patients with known or suspected CAD clinically referred for invasive angiography.

Main study parameters: Myocardial perfusion defect on dynamic CT perfusion imaging, and diagnostic accuracy as compared invasive FFR.

Co Principle Investigators Koen Nieman MD PhD, Erasmus University Medical Center Fabian Bamberg MD PhD, University of Tübingen.

Investigators Valerie Schmidt-Honndorf PhD, University of Tübingen Tobias Geisler MD PhD, University of Tübingen Joost Daemen MD PhD, Erasmus University Medical Center Adriaan Coenen MD, Erasmus University Medical Center Stephan Achenbach MD PhD, Erlangen University Micheala M. Hell MD, Erlangen University Rozemarijn Vliegenthart MD PhD, UMC Groningen Pim van der Harst MD PhD, UMC Groningen Francesca Pugliese MD PhD, Queen Mary University of London Kakuya Kitagawa MD PhD, Mie University Hatem Alkadhi MD PhD, University Hospital Zurich, Switzerland Robert Manka MD PhD, University Hospital Zurich, Switzerland

Inclusion Criteria:

• Age 21-75 years
• Stable angina symptoms, suspected or known CAD, and referred for invasive angiography on clinical grounds.
• Ability to provide informed consent
• Ability to perform a 20-30 second breath hold

Exclusion Criteria:

• Hemodynamically and clinically unstable condition (angina at rest, malignant arrhythmias)
• Prior, documented myocardial infarction, other than (procedure related) minor type II myocardial infarction, which includes Q waves on the ECG or evidence of myocardial infarction on prior non-invasive imaging.
• Prior stenting or coronary artery bypass graft surgery
• Significant other cardiovascular conditions affecting the interpretation of MPICT, including, but not limited to: clinical heart failure, IECD (pacemaker/ICD), severe valvular heart disease or prosthetic valves, significant intra-cardiac shunting or other relevant congenital heart disease.
• eGFR<60 ml/kg/min
• BMI>30 kg/m2, or weight >120 kg.
• Atrial fibrillation or other arrhythmia, >6 ectopic beats / min
• Known or suspected allergy to iodinated contrast medium
• Pregnancy cannot be excluded
• Contra-indications for adenosine: bronchial asthma, second or third degree atrioventricular block, blood pressure <110/70 mmHg, allergies or severe side effects in the past.

Patients with know or suspect coronary artery diseased, referred for invasive coronary angiography.