Ablation of persistent atrial fibrillation based on high density voltage mapping and complex fractionated atrial electrograms: A randomized controlled trial.

INTRODUCTION: Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) catheter ablation. However, a PVI alone has been considered insufficient for persistent AF. This study aimed to evaluate the efficacy of persistent AF ablation targeting complex fractionated atrial electrogram (CFAE) areas within low voltage zones identified by high-resolution mapping in addition to the PVI. METHODS: We randomized 50 patients (mean age 58.4 ±â€Š9.5 years old, 86.0% males) with persistent AF to a PVI + CFAE group and PVI only group in a 1:1 ratio. CFAE and voltage mapping was performed simultaneously using a Pentaray Catheter with the CARTO3 CONFIDENSE module (Biosense Webster, CA, USA). The PVI + CFAE group, in addition to the PVI, underwent ablation targeting low voltage areas (<0.5 mV during AF) containing CFAEs. RESULTS: The mean persistent AF duration was 24.0 ±â€Š23.1 months and mean left atrial dimension 4.9 ±â€Š0.5 cm. In the PVI + CFAE group, AF converted to atrial tachycardia (AT) or sinus rhythm in 15 patients (60%) during the procedure. The PVI + CFAE group had a higher 1-year AF free survival (84.0% PVI + CFAE vs 44.0 PVI only, P = .006) without antiarrhythmic drugs. However, there was no difference in the AF/AT free survival (60.0% PVI + CFAE vs 40.0% PVI only, P = .329). CONCLUSION: Persistent AF ablation targeting CFAE areas within low voltage zones using high-density voltage mapping had a higher AF free survival than a PVI only. Although recurrence with AT was frequent in the PVI+CFAE group, the sinus rhythm maintenance rate after redo procedures was 76%.

Supraventricular tachyarrhythmias in patients with a persistent left superior vena cava.

Aims: A persistent left superior vena cava (PLSVC) is the most common thoracic venous anomaly. This venous anomaly can impact the evaluation and treatment of supraventricular tachyarrhythmia (SVA). The aim of this study was to assess the proportion and characteristics of PLSVC in adult SVA patients. Methods and results: From July 2002 to July 2012, clinical and procedural data from databases of 10 cardiac electrophysiology laboratories in the Yeungnam region of the Republic of Korea were reviewed. Of 6662 adult SVA patients who underwent an EP study or catheter ablation of SVA during the 10-year study period, 18 patients had PLSVC (mean age 47.6 ± 14.8 years, 10 men). The proportion of PLSVC in adult SVA patients was 0.27% (18/6662). SVA type and procedural outcomes of radiofrequency (RF) catheter ablation in these patients were investigated and the results were as follows: successful slow pathway modification in six of seven patients with atrioventricular nodal reentrant tachycardia (AVNRT), successful ablation of accessory pathway in three of four patients with atrioventricular reentrant tachycardia, and successful ablation of atrial tachycardia (cavotricuspid isthmus-dependent in two, septal macroreentry in one, focal from the PLSVC in one) in three of four patients. In one patient with junctional tachycardia, catheter ablation failed. In two patients with atrial fibrillation, catheter ablation was successful. Conclusion: Among adult SVA patients who underwent an EP study or RF catheter ablation during the 10-year study period, 0.27% had PLSVC. The most common type of SVA was AVNRT. The success rate of catheter ablation was 82% in SVA patients with PLSVC. There were no procedure-related complications.

Radiofrequency Catheter Ablation Targeting the Vein of Marshall in Difficult Mitral Isthmus Ablation or Pulmonary Vein Isolation.

INTRODUCTION: The ligament of Marshall may hinder the creation of mitral isthmus (MI) block or pulmonary vein (PV) isolation (PVI) in radiofrequency (RF) catheter ablation of atrial fibrillation (AF). We aimed to assess the benefit of RF ablation targeting the vein of Marshall (VOM) in failed cases of MI block or PVI. METHODS AND RESULTS: We reviewed the medical records of patients who underwent RF ablation targeting the VOM after failed MI ablation or left PVI using the conventional method, which included circumferential point-by-point ablation around the PV antrum and carina for PVI, and endocardial MI and epicardial distal coronary sinus (CS) ablation for MI block. The VOM was identified by using selective VOM venography with an external irrigation RF ablation catheter. RF ablation targeting the VOM was performed with RF application at the ostium of the VOM inside the CS or at the endocardial region facing the VOM course. During the set period, CS venography was performed in 42 patients after failure of left PVI (n = 5) or MI block (n = 37). Under CS venography, the VOM was visualized in 22 of 42 patients (MI = 19 and PVI = 3). During selective venography of the VOM, no procedure-related complication was observed. RF application targeting the VOM successfully achieved MI block in 13 patients (68.4%) and PVI in 2 patients (66.7%). CONCLUSION: Selective VOM venography using an irrigated ablation catheter is feasible and safe. RF ablation targeting the VOM may provide additional benefit in failed cases of MI block or PVI.