Fehmi Keçe

Chapter 1 20 1.5 Outline of this thesis The purpose of this thesis is to investigate different ablation tools for efficacy and safety, with emphasis on two randomized controlled trials studying cerebral embolism with the PVAC-Gold catheter and investigating optimization of the cryoballoon ablation protocol. In chapter 2 as part of the introduction of this thesis, the reported incidence of complications is summarized, considering specific device-related aspects for point-by-point, multi-electrode and balloon-based devices. Secondly, the impact of technical advances on procedural outcome, length and radiation exposure is discussed. In chapter 3 and first part of this thesis the first randomized clinical trial, studying the differences in incidence and clinical significance of asymptomatic cerebral embolismbetween themulti-electrode PVAC- Gold catheter and the Thermocool catheter, is presented. In chapter 4 the biophysical data of the PVAC-Gold ablations from this trial are analysed to gain insight in the genesis of micro-emboli with this device. In chapter 5 the origin of cerebral micro-emboli in this trial is studied from a haematological perspective by analysing different coagulation and haemostatic markers predicting these micro-emboli. In chapter 6 and second part of this thesis, the second randomized controlled trial optimizing the cryoballoon ablation duration using dormant conduction to reveal incomplete pulmonary vein isolation is presented. In chapter 7 the biophysical data of ablation with the second-generation cryoballoon is analysed to predict incomplete isolation. In chapter 8 the impact of ablation surface area of the posterior box lesion on ablation outcome in persistent AF is studied. In chapter 9 and chapter 10 conclusions of the chapters are summarized.