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Electrical cardiac pacing today is the standard therapy for symptomatic bradycardia. Importantly, despite technical advantages, complications associated with conventional transvenous pacing leads and pockets are still challenging in a relevant number of patients. Beyond cosmetic benefits, miniaturized leadless pacemaker may partly overcome these limitations and beneficially influence implantation-related physical restrictions. Initial findings with single-chamber pacemakers for right ventricular pacing, which are completely implanted via a femoral venous vascular access, are promizing. In summary, leadless pacing offers novel perspectives regarding cardiac implantable electronic devices although acute safety and the long-term performance of these systems needs to be determined in more detail., (© Georg Thieme Verlag KG Stuttgart · New York.)

Atrial fibrillation is the most common form of arrhythmia worldwide and is associated with potentially severe complications. Apart from antiarrhythmic drug therapy, interventional treatment by catheter ablation has emerged as an effective and safe alternative notably for the paroxysmal form. The pulmonary veins (PV) have been identified as a major source in the setting of paroxysmal atrial fibrillation. Circumferential wide area PV isolation, optimization of procedural techniques and the positioning of an ablation line deep in the left atrium have contributed to the increased success rates; however, the procedure is still associated with potentially severe complications and should therefore be carried out in centers with sufficient case numbers and operators with corresponding training and experience.

Catheter ablation for paroxysmal atrial fibrillation is a meanwhile established therapy option, which is most frequently performed using radiofrequency ablation. Mid-term success rate of 70 % are achievable with a single ablation procedure. However, the mechanistics of persistent atrial fibrillation are less well understood and catheter ablation is a far more challenging procedure. Different ablation approaches are being performed to treat persistent atrial fibrillation ranging from sole pulmonary vein isolation to additional ablation of fractionated electrograms aiming for termination of atrial fibrillation. Thus far, it has not been investigated which strategy is most successful in treating persistent atrial fibrillation. After extended ablation of atrial fibrillation, occurrence of organized atrial arrhythmias is not uncommon and can be successfully ablated. These consecutive arrhythmias can be considered as a next step towards stable sinus rhythm after repeat ablation. Improvement of mapping methods as well as a better understanding of mechanisms of atrial fibrillation may increase success rate of catheter ablation of persistent atrial fibrillation and may also help to improve success rate of these complex procedures.

Catheter ablation of atrial fibrillation has evolved as a widely accepted therapy approach and is now also incorporated in the current guidelines.A major limitation consists of the limited three-dimensional visualization of the complex three-dimensional structures in the left atrium since most procedures have routinely been performed using fluoroscopy alone. Another unsolved problem is the limited durability of lesions sets performed with radiofrequency ablation and therefore somewhat disappointing long-term ablation results besides fluoroscopy exposition for patient and operator as required for safe catheter manipulation.In the recent years we have gained substantial insight with respect to arrhythmia mechanism. At the same time new techniques and developments have become available to improve catheter ablation results.The present article summarizes the available opportunities with respect to three-dimensional mapping including CT/MRI image integration and gives an overview of the robotic and magnetic systems available for catheter ablation.

Interventional treatment for atrial fibrillation (AF) has been introduced as a therapeutic option soon after the pulmonary veins (PV) have been discovered as the dominant sources of paroxysmal atrial fibrillation (PAF). Elimination of PV conduction is the initial goal during catheter ablation in this setting. The success rate after the initial procedure varies between 60% and 85%, with > 80% after subsequent interventions. Supported by the current guidelines, interventional treatment of AF is indicated in case of symptomatic arrhythmias refractory to antiarrhythmic treatment. The introduction of the combined, stepwise approach has been another important breakthrough with regard to the treatment of chronic persistent atrial fibrillation (CAF). This strategy includes the combination of all conventional ablation strategies (pulmonary vein isolation [PVI], defragmentation, linear ablation) with the goal of AF termination by radiofrequency current. The first procedure for CAF treatment is quite frequently also only the first step toward stable sinus rhythm with a favorable outcome after AF termination (> 80% sinus rhythm). In more than half of the patients predominantly atrial arrhythmias other than AF have to be targeted in a second procedure. This approach is currently under clinical investigation and so far not "clinically established" due to the fact that it is a quite time-consuming and challenging procedure even in experienced centers. Future studies may help to identify predictors for procedure failure (e.g., left atrial size, AF duration, atrial cycle length) in order to improve patient selection. Additionally, it has to be underscored, that in PAF the relatively high recurrence rate after the first procedure still is the subject of further investigations. This aspect might be improved by the introduction of novel strategies (i.e., testing of concealed PV conduction after ablation with adenosine) or technologies (i.e., robotic navigation) for PAF ablation.