New Results in Catheter Ablation for Atrial Fibrillation

Pulmonary vein isolation (PVI) is the cornerstone of rhythm-control therapy for atrial fibrillation (AF). A few years ago, contact force-sensing ablation catheters (CFSAC) were introduced. Nowadays the use of CFSAC became a part of the everyday practice. The durability of PVI depends much on the accurate lesion creation. The recently developed techniques (ablation index, CLOSE protocol) may facilitate the procedure in terms of achieving durable PVI which has already been confirmed by randomized trials. In this chapter, we would like to introduce the theoretical background of PVI and compare different techniques (radiofrequency point-by-point, cryoballoon, additional ablation lines for persistent AF) with special highlight on the importance of durable PVI

High-Power, Short-Duration Ablation in the Treatment of Atrial Fibrillation Patients

Catheter ablation is the cornerstone of the rhythm control treatment of atrial fibrillation (AF). During this procedure, creating a contiguous and durable lesion set is essential to achieve good long-term results. Radiofrequency lesions are created in two phases: resistive and conductive heating. The ablation catheters and the generators have undergone impressive technical developments to enable homogenous and good-quality lesion creation. Despite recent years’ achievements, the durable isolation of the pulmonary veins remains a challenge. These days, intensive research aims to evaluate the role of high-power radiofrequency applications in the treatment of patients with cardiac arrhythmias. The use of high-power, short-duration applications might result in a uniform, transmural lesion set. It is associated with shorter procedure time, shorter left atrial, and fluoroscopy time than low-power ablation. This technique was also associated with a better clinical outcome, possibly due to the better durability of lesions. Multiple clinical studies have proven the safety and efficacy of high-power, short-duration PVI

Rivaroxabankezelés mellett kialakult bal pitvari fülcsethrombus sikeres kezelése direkt trombininhibitorral

The authors present the history of a 62-year-old man on continuous rivaroxaban therapy who was scheduled for pulmonary vein isolation due to persistent atrial fibrillation. Preoperative transesophageal echocardiography detected the presence of left atrial appendage thrombus. Thrombophilia tests showed that the patient was heterozygous carrier of the methylene-tetrahydrofolate reductase gene mutation. The authors hypothesized that a direct thrombin inhibitor might exert a more appropriate effect against thrombosis in this case and, therefore, a switch to dabigatran was performed. After two months of anticoagulation with the direct thrombin inhibitor and folic acid supplementation the thrombus resolved. The authors underline that thrombus formation may develop in atrial fibrillation even if the patient is adequately treated with rivaroxaban. This case suggests, that methylene-tetrahydrofolate reductase gene mutation may modulate the efficacy of direct Xa factor inhibitors. According to this case history, dabigatran may be an effective therapeutic option in resolving established thrombus. Orv. Hetil., 2016, 157(4), 154-156