Giovanni Volpato

and 14 more

Background Provide a brief overview of recent technological advances that can potentially give information for treatment of different kind of arrhythmias. Methods In this report, we describe the features of Omnipolar technology (OT) using high density mapping catheter and we report five different scenario in which this new tool can give some important information to understand arrhythmia’s substrate and guide the treatment. OT combine three unipolar and two bipolar signals and provides maximum voltage regardless of electrode-wavefront orientation, local wavefront activation direction and local measurements of wave speed: it allow to create a velocity map. Results OT has been used to study different types of supraventricular tachycardias. Regarding reentry tachycardias, velocity map has allowed the characterization and definition of the impulse velocity along the dual nodal pathway and the accessory pathways (AP). As regards atrial flutter, it has successfully allowed the definition of the slowest zone of the critical isthmus and radiofrequency (RF) delivery at that point resulted in termination of the arrhythmia. During mapping of the left atrium in sinus rhythm, the velocity map allowed the identification of the course of the Bachmann’s bundle, which could potentially play a role during the ablation of persistent atrial fibrillation (AF). Conclusion OT and velocity map offer significant advantages in the management of challenging arrhythmias, and can potentially improve the efficacy of the treatment of some arrhythmias such as atrial flutter and AF.

Giuseppe De Martino

and 10 more

Background: Outcomes of catheter ablation (CA) among patients with non-paroxysmal atrial fibrillation (AF) are largely disappointing. Objective: We sought to evaluate the feasibility, effectiveness, and safety of a single-stage stepwise endo-/epicardial approach in patients with persistent/longstanding-persistent AF. Methods: We enrolled 25 consecutive patients with symptomatic persistent (n=4) or longstanding-persistent (n=21) AF and at least one prior endocardial procedure, who underwent CA using an endo-/epicardial approach. Our anatomical stepwise protocol included multiple endocardial as well as epicardial (Bachmann’s bundle [BB] and ligament of Marshall ablations) components, and entailed ablation of atrial tachycardias emerging during the procedure. The primary outcome was freedom from any AF/atrial tachycardia episode after a 3-month blanking period. The secondary outcome was patients’ symptom status during follow-up. Results: The stepwise endo-/epicardial approach allowed sinus rhythm restoration in 72% of patients, either directly (n=6, 24%) or after AF organization into atrial tachycardia (n=12, 48%). BB’s ablation was commonly implicated in arrhythmia termination. After a median follow-up of 266 days (interquartile range, 96 days), survival free from AF/atrial tachycardia was 88%. Antiarrhythmic drugs could be discontinued in 22 patients (88%). As compared to baseline, more patients were asymptomatic at 9-month follow-up (0% vs- 56%, p=0.02). Five patients (20%) developed mild medical complications, whereas one subject (4%) had severe kidney injury requiring dialysis. Conclusion: a single-stage endo-/epicardial CA resulted in favorable rhythm and symptom outcomes in a cohort of patients with symptomatic persistent/longstanding-persistent AF and one or more prior endocardial procedures. Epicardial ablation of BB was commonly implicated in procedural success.