[Update on coronary CT-more than just anatomical imaging? : Current guidelines and functional CT techniques for the quantification of stenoses]. / Update Kardio-CT ­ mehr als nur anatomische Bildgebung? : Aktuelle Leitlinien und funktionelle CT-Techniken zur Stenosequantifizierung.

BACKGROUND: Coronary CT angiography (cCTA) has a high negative predictive value for ruling out significant coronary stenoses. However, it is limited in determining hemodynamic significance of a stenosis and hence to prove the indication for therapy. OBJECTIVES: When and how is cCTA used according to current guidelines? Which functional CT techniques are available to test for hemodynamic significance of coronary stenoses? MATERIALS AND METHODS: The value of cCTA is explained on the basis of current guidelines by the European Society of Cardiology (ESC) for the diagnosis of chronic coronary syndromes. Functional CT techniques which test for hemodynamic significance of coronary stenoses are myocardial CT-perfusion (CT­P) and CT-based fractional flow reserve (CT-FFR). RESULTS: The new ESC guidelines classify cCTA as a class 1 recommendation for diagnosing coronary artery disease in symptomatic patients with low clinical likelihood. If clinical likelihood is high or an at least moderate stenosis is detected with cCTA, noninvasive functional (stress) imaging is preferred. There is a large body of evidence for CT­P and CT-FFR as functional tests. CONCLUSION: In the current guidelines, cCTA is highly recommended for the diagnosis of coronary artery disease. The functional CT techniques CT­P and CT-FFR have shown high diagnostic accuracy for myocardial ischemia of coronary stenoses in many clinical studies. However, these methods are not part of current guidelines yet and clinical adoption is still low.