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Purpose: Catheter ablation of atrial fibrillation (AF) is now one of the most frequently performed ablation procedures, but there are currently 2 important challenges: achieving permanent/durable rather than transient pulmonary vein isolation (PVI) and improving the results of ablation for the wider patient population with persistent AF. Methods: Recent technical advances in the technique of ablation and the results of clinical trials aimed at achieving more permanent and durable PVI are reviewed. We also summarize recent advances in identifying atrial fibrosis and in understanding the pathophysiology of AF relevant to selecting patients for ablation of persistent AF. Findings: The use of contact force-sensing technology, adenosine testing after ablation, and pace capture- guided ablation all have the potential for achieving more durable ablation. Selection of patients suitable for ablation of persistent AF may be improved by assessing the extent of atrial fibrosis with delayed enhancement imaging with cardiac magnetic resonance or by assessing the pattern of atrial electrical activity with the use of complex atrial electrograms. Advances in treatment are likely to result from the recognition of localized rotors and focal sources as primary sustaining mechanisms for all types of human AF and in the use of noninvasive mapping for their identification. Linear ablation to supplement PVI may improve the results of AF ablation. Implications: Rapidly unfolding advances in the techniques of AF ablation and the understanding of mechanisms of AF hold promise for improving the durability of PVI and for extending the technique to carefully selected patients with persistent AF. [ABSTRACT FROM AUTHOR]

Over the past decade, there has been an exponential increase in the number of catheter ablation procedures performed for atrial fibrillation (AF). While for paroxysmal AF, proximal pulmonary vein isolation is sufficient in the majority of cases, ablation of persistent and longstanding AF requires an extensive surgical-like procedure. This approach is correlated with a high rate of AF termination; however, this is achieved at the cost of at least one atrial tachycardia (AT) during the index procedure or during the patient's follow-up in the vast majority of cases. As these ATs are often multiple, complex, and frequently more symptomatic than AF, they constitute the last and frequently the most difficult step in ablation for patients with persistent AF. This review concentrates on the practical approaches to the treatment of AT in the context of AF ablation and provides an algorithm that aims at facilitating mapping and ablation strategies using conventional electrophysiological tools. [ABSTRACT FROM AUTHOR]

Pulmonary Vein Arrhythmia. Introduction: The incidence and characteristics of dissociated arrhythmia confined to the pulmonary vein (PV) following disconnection have not been described in a large number of patients with paroxysmal atrial fibrillation. Methods and Results: This was a prospective study of 152 patients (29 female, mean age 51 ± 11 years) referred for catheter ablation of drug-refractory paroxysmal atrial fibrillation. Following ostial ablation, the rate and regularity of any dissociated venous activity was analyzed with and without isoproterenol infusion (to achieve a heart rate of 120–140 beats/min). Patients then were classified according to their venous dissociated activity. Group 1 consisted of patients in whom the dissociated PV spike had a slow rhythm >1,200 ms. Group 2 consisted of patients with spontaneous repetitive dissociated discharges confined in the vein with a cycle length <400 ms. A total of 384 PVs were ablated in 152 patients. Disappearance of all venous potentials was observed in 88% of the treated veins; at least one dissociated venous potential was observed in the remaining 12%. Group 1 activity was seen more often than group 2 (23 patients, mean cycle length 2,300 ± 1,100 ms vs 13 patients, mean cycle length 179 ± 77 ms). Dissociated PV arrhythmia was seen most often in the right superior PV (19%). Conclusion: Dissociation as the endpoint of PV disconnection was observed in 12% of PVs. Due to the capricious nature of this activity, the actual incidence is almost certainly higher. The dissociated venous rhythm usually is slow and, less commonly, is rapid and repetitive. (J Cardiovasc Electrophysiol, Vol. 14, pp. 1173-1179, November 2003) [ABSTRACT FROM AUTHOR]

Presents a study which determined the radiation exposure to patient and medical staff during atrial fibrillation compared with that measured during ablation of other arrhythmias in the same laboratory. Methods; Results and discussion; Conclusion.

Background Catheter ablation is increasingly used to manage atrial fibrillation, but arrhythmia recurrences are common. Adenosine might identify pulmonary veins at risk of reconnection by unmasking dormant conduction, and thereby guide additional ablation to improve arrhythmia-free survival. We assessed whether adenosine-guided pulmonary vein isolation could prevent arrhythmia recurrence in patients undergoing radiofrequency catheter ablation for paroxysmal atrial fibrillation. Methods We did this randomised trial at 18 hospitals in Australia, Europe, and North America. We enrolled patients aged older than 18 years who had had at least three symptomatic atrial fibrillation episodes in the past 6 months, and for whom treatment with an antiarrhythmic drug failed. After pulmonary vein isolation, intravenous adenosine was administered. If dormant conduction was present, patients were randomly assigned (1:1) to additional adenosine-guided ablation to abolish dormant conduction or to no further ablation. If no dormant conduction was revealed, randomly selected patients were included in a registry. Patients were masked to treatment allocation and outcomes were assessed by a masked adjudicating committee. Patients were followed up for 1 year. The primary outcome was time to symptomatic atrial tachyarrhythmia after a single procedure in the intention-to-treat population. The trial is registered with ClinicalTrials.gov, number NCT01058980. Findings Adenosine unmasked dormant pulmonary vein conduction in 284 (53%) of 534 patients. 102 (69·4%) of 147 patients with additional adenosine-guided ablation were free from symptomatic atrial tachyarrhythmia compared with 58 (42·3%) of 137 patients with no further ablation, corresponding to an absolute risk reduction of 27·1% (95% CI 15·9–38·2; p<0·0001) and a hazard ratio of 0·44 (95% CI 0·31–0·64; p<0·0001). Of 115 patients without dormant pulmonary vein conduction, 64 (55·7%) remained free from symptomatic atrial tachyarrhythmia (p=0·0191 vs dormant conduction with no further ablation). Occurrences of serious adverse events were similar in each group. One death (massive stroke) was deemed probably related to ablation in a patient included in the registry. Interpretation Adenosine testing to identify and target dormant pulmonary vein conduction during catheter ablation of atrial fibrillation is a safe and highly effective strategy to improve arrhythmia-free survival in patients with paroxysmal atrial fibrillation. This approach should be considered for incorporation into routine clinical practice. INSET: Panel: Research in context.. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic poses a significant stress on health resources in Australia. The Heart Rhythm Council of the Cardiac Society of Australia and New Zealand aims to provide a framework for efficient resource utilisation balanced with competing risks when appropriately treating patients with cardiac arrhythmias. This document provides practical recommendations for the electrophysiology (EP) and cardiac implantable electronic devices (CIED) services in Australia. The document will be updated regularly as new evidence and knowledge is gained with time. [ABSTRACT FROM AUTHOR]

Background: The BioMonitor 2 Pilot Study assessed the implantation procedure, the sensing amplitude and the remote monitoring transmission success rate of the second generation implantable cardiac monitor, the BioMonitor 2 (Biotronik, Berlin, Germany).Methods: This was a prospective, multi-centre, single-arm, non-randomised study involving seven operators in five sites across Australia. Data were collected at implantation, during clinic visits at 1 week and 1 month post-implantation, and through wireless remote monitoring.Results: Thirty patients with indications for long-term cardiac monitoring underwent successful insertion of a study device. The median implantation time was 9 minutes (interquartile range (IQR) 5-14 mins). The mean R-wave amplitude at 1 week was 0.75±0.39mV and remained stable over the follow-up period. Within 1 day, 97% of the patients connected to the remote monitoring network and daily messages were transmitted on 93.8% of all study days. Seventy-six per cent of patients transmitted at least one subcutaneous ECG (sECG), with a median number of sECGs per patient of seven (IQR 3-37) within 28 days.Conclusions: The results of the BioMonitor 2 Pilot study confirm the excellent sensing amplitudes afforded by this new device and the utility of the implantation tools and technique. Patient compliance with and the transmission success rate of the home monitoring system were excellent. [ABSTRACT FROM AUTHOR]