Non-fluoroscopy Ablation of AF/AT

The hypothesis is that patients who undergo one or more TSP(s) for atrial fibrillation or left atrial tachycardia can be studied without the use of fluoroscopy which should result in a low or ZERO overall radiation exposure for the entire ablation procedure. The investigators will assess the feasibility, safety and efficacy of this new approach. The patient will be admitted in hospital as for a standard procedure and discharged the next day. Before admission, the patient undergoes a CMR/CT scan (routine in our centre). To avoid total radiation CMR would be preferred, if possible. The technique of the TSP and the use of the RF needle is commonly used worldwide. The ability to visualize the needle tip on the 3D electroanatomical mapping system facilitates the procedure. The additional visualization by TOE helps to assure that the fossa ovalis has been correctly identified. After the TSP, the ablation procedure itself will be carried out as conventionally performed using the catheter visualization on the 3D mapping system. An ECG and an echocardiogram are performed before discharge (as standard care). At 3 months the patient comes for the first visit and has an ECG, a Holter and symptom questionnaire. At 6 months, the patient has second visit which includes an ECG, a symptom questionnaire, a Holter and an echocardiogram. If recurrences of any arrhythmia occur, the patient can be scheduled for a second ablation procedure without any restrictions.