An Update on the Energy Sources and Catheter Technology for the Ablation of Atrial Fibrillation

Impact of Variableorientation and Flow Rates on Radiofrequency Ablation Lesions Created by Externally Irrigated Catheters: An Ex-Vivo Study

The impact of variability in irrigation rates and catheter orientation on radiofrequency ablation (RF) lesion creation has not been studied systematically for the uniformly irrigated 56-pore (56P) catheter. This study aimed to analyze the impact of irrigation flow rates (IFRs) and catheter orientation (CO) settings on RF lesions sizes produced by a 56P irrigation catheter in a power-controlled mode using an ex-vivo model. RF lesions were created in strips of chicken muscle in a saline bath heated to 37°C with 56P and 6P catheters using low flow rate (LFR) at 2 cc/min and standard flow (SFR) irrigation rates at 8 cc/min for 56P and 17 cc/min for 6P with horizontal (HO) and vertical (VO) catheter orientations. Ablation power of 20W was delivered for 30 seconds with a mean contact force of 10 g. Sixty RF lesions were analyzed. For the 56P catheter, in contrast to the 6P catheter lesion geometry was independent of CO and IFR in our model. Although 6P catheter had slightly deeper lesions, the overall lesion volumes were similar for 6P and 56P catheters. CO and IFR appeared to have minimal impact on lesion volume creation with 56P catheter. In head-to-head comparison the 6P and 56P irrigated catheters performed similarly.

Management of Patients with Atrial Fibrillation: Focus on Treatment Options

Atrial fibrillation (AF) is leading cardiac arrhythmia with important clinical implications. Its diagnosis is usually made on the basis on 12-lead ECG or 24-hour Holter monitoring. More and more clinical evidence supports diagnostic use of cardiac event recorders and cardiovascular implantable electronic devices (CIED). Treatment options in patients with atrial fibrillation are extensive and are based on chosen rhythm and/or rate control strategy. The use and selected contraindications to AF related pharmacotherapy, including anticoagulants are shown. Nonpharmacological treatments, comorbidities and risk factors control remain mainstay in the treatment of patients with AF. Electrical cardioversion consists important choice in rhythm control strategy. Much progress has been made in the field of catheter ablation and cardiac surgery methods. Left atrial appendage occlusion/closure may be beneficial in patients with AF. CIED are used with clinical benefits in both, rhythm and rate control. Pacemakers, implantable cardioverter-defibrillators and cardiac resynchronization therapy devices with different pacing modes have guaranteed place in the treatment of patients with AF. On the other hand, the concepts of permanent leadless cardiac pacing, atrial dyssynchrony syndrome treatment and His-bundle or para-Hisian pacing have been proposed. This review summarizes and discusses current and novel treatment options in patients with atrial fibrillation.