Non-invasive Fractional Flow Reserve and Antiplatelet Therapy in Cardiac Interventions: An Epidemiological Perspective

The first part of this thesis evaluates alternative less- and non-invasive methods to determine fractional flow reserve (FFR) in patients with stable chest pain. The focus is on CT-based FFR (CT-FFR) and angiography-based FFR (QFR). This thesis demonstrates that new, less- and non-invasive imaging techniques combining both anatomical and functional information have good diagnostic accuracy for demonstrating hemodynamically relevant coronary artery disease. The impact of QFR on clinical workflow and how it may lead to a reduction in invasive FFR measurements is also evaluated. Currently, there is no consensus on the optimal diagnostic pathway of patients with chest pain and the role of new diagnostic tests. The first part concludes with the trial design of the iCORONARY study in which we evaluate different diagnostic pathways.
The second part of this thesis focuses on research on antiplatelet therapies for patients undergoing cardiac interventions and the methodological challenges these studies face. In this dissertation, we evaluate the effect of adding ticagrelor on venous graft patency in a double-blind randomized trial. However, we found no beneficial effect of ticagrelor on graft occlusions. Also in this thesis, we evaluate antiplatelet therapy after TAVI in patients with and without indication for oral anticoagulants. In both patient groups, we showed that omission of clopidogrel led to reduced bleeding but not to an increase in the composite endpoint of thromboembolic events.