Ablation of the AV node with His bundle pacing for persistent AF

Persistent atrial fibrillation remains one of the most vexing rhythm disturbances encountered in adult cardiology. When antiarrhythmic drugs lose their punch and catheter ablation of pulmonary vein triggers fails to restore durable sinus rhythm, clinicians are often left searching for a strategy that controls symptoms without condemning the patient to lifelong ventricular pacing from an apical site. Ablation of the atrioventricular node combined with conduction system pacing has matured into a pragmatic, evidence-supported option, particularly for older patients with reduced ejection fraction or significant comorbidities.

This article walks through a stepwise approach to the combined procedure, drawing on contemporary electrophysiology practice. It is written for cardiac registrars, fellows, and consultant electrophysiologists working across Australian tertiary centres and regional hospitals, where patient demographics, referral pathways, and funding models shape how these therapies are delivered.

Patient selection and indications

The ideal candidate for AV node ablation with His bundle pacing is an older patient with symptomatic persistent atrial fibrillation, a left ventricular ejection fraction that has either been compromised by tachycardia-mediated cardiomyopathy, or one in whom permanent pacing is anticipated regardless of rhythm outcome. Younger patients with preserved ventricular function and reversible triggers should generally be steered toward rhythm control strategies first, including repeat ablation or pulsed field approaches if available. Shared decision-making is essential, particularly when discussing the irreversibility of AV node ablation. Patients need to understand that the trade-off involves trading one set of problems for another, namely pacemaker dependence and the need for generator changes over a lifetime.

In Australia, referral patterns often bring these patients to large tertiary units such as Royal Prince Alfred in Sydney, MonashHeart in Melbourne, or the Royal Adelaide. Rural and remote patients from the Pilbara, the Top End, or western Queensland may travel considerable distances and arrive with limited prior workup. The conversation therefore needs to address not only the procedure itself but also the logistics of follow-up, which often falls to a combination of local general physicians, telehealth clinics, and visiting cardiology outreach services. A frank discussion about driving restrictions in the immediate post-procedure period also resonates with Australian patients who rely heavily on their cars in suburban and regional settings.

Pre-procedural planning and imaging

Pre-procedural planning begins with a 12-lead ECG documenting the persistent arrhythmia, a transthoracic echocardiogram to assess chamber size, ventricular function, and valvular pathology, and baseline bloodwork including renal function, thyroid studies, and a full coagulation profile. Many Australian units now use cardiac CT to delineate coronary sinus anatomy and to screen for incidental pulmonary vein stenosis or atrial thrombus if the patient is in sinus rhythm at the time of scanning. Anticoagulation strategy must be reviewed well in advance; direct oral anticoagulants funded through the Pharmaceutical Benefits Scheme are typically continued uninterrupted, with the procedure timed to the next scheduled dose.

Device implantation planning deserves equal weight. The operator should select a venous access approach that allows both ablation catheters and pacing hardware to be delivered without conflict. Most Australian electrophysiologists place the pacing lead first via cephalic or axillary access, secure the generator in a pre-pectoral pocket, and then proceed to ablation through femoral venous access. Anaesthesia teams accustomed to the hybrid environment coordinate closely with the proceduralist, as general anaesthesia or deep sedation requirements vary between operators and patient comorbidities. In private hospital settings, prior approval from insurers and clear documentation of clinical indication help avoid funding disputes that can otherwise delay the case.

The stepwise ablation approach

Once vascular access is secured and the His bundle lead is positioned, the ablation catheter is advanced to the right atrium. The compact AV node lies in the triangle of Koch, identified by a combination of anatomic landmarks, intracardiac electrograms, and fluoroscopic guidance. In persistent atrial fibrillation, the ablation endpoint is complete heart block, verified by the absence of conducted ventricular beats during a waiting period of at least 20 to 30 minutes, with isoprenaline or atropine challenges where indicated to unmask residual conduction.

Ablation energy is delivered gradually, starting at the inferior aspect of the compact node and titrating superiorly. Contemporary operators often use irrigated radiofrequency energy, though cryoablation is a reasonable alternative in selected cases. Junctional ectopy during energy delivery is a useful marker of proximity to the node, and the endpoint of complete AV block should be confirmed both in sinus rhythm (if achievable through cardioversion) and during ongoing fibrillation. Many Australian labs perform a final check with incremental atrial pacing to ensure no residual concealed conduction remains. Recordings, lesion annotations, and fluoroscopy times should be archived carefully, both for quality assurance and for ongoing registry contributions that shape the regional evidence base.

His bundle pacing: lead placement and optimisation

His bundle pacing is the cornerstone of this combined strategy because it preserves physiological ventricular activation and avoids the dyssynchrony associated with right ventricular apical pacing. The lead is delivered through a dedicated sheath, often with the aid of a mapping catheter to identify the His signal precisely. Selective capture, where the pacing stimulus directly activates the His-Purkinje system, is preferred when achievable, though non-selective capture remains acceptable when thresholds are favourable.

Operators should be alert to the implications of injury current at the time of lead deployment. His bundle injury current during lead implantation is a useful predictor of stable pacing parameters and long-term lead performance, and recognising its presence helps anticipate thresholds in the days following implantation. Capture thresholds above 2.0 V at 1 ms, or failure to demonstrate injury current, should prompt consideration of left bundle branch area pacing as a bail-out strategy. The Australian private health insurance system, with its schedule of benefits covering both the procedure and the device, supports the use of newer conduction system leads, though rebate structures vary between insurers and hospital locations, and patients should be counselled about any out-of-pocket costs before the day of surgery.

Post-procedural care and follow-up

Post-procedural care begins with a monitored bed for at least 24 hours, chest radiography to confirm lead position and exclude pneumothorax, and a pacing check before discharge. Device interrogation at one week, one month, and three months allows threshold maturation to be tracked and atrial sensing characteristics to be reviewed if the patient returns to sinus rhythm. Anticoagulation is continued according to standard CHA₂DS₂-VASc guidelines, with no modification based on rhythm outcome, and routine bloodwork is repeated at intervals consistent with local protocol.

Cardiac rehabilitation programs, available through most public hospitals and some private providers, help patients regain confidence after the procedure. Many Australian centres now offer hybrid cardiac rehabilitation models that combine centre-based exercise with home monitoring, which suits patients who have travelled from regional Queensland or the Northern Territory. Should complications arise, or if generator change procedures are required, patients or clinicians can reach the editorial or clinical enquiry service through the journal's contact page. Long-term follow-up also provides an opportunity to revisit stroke prevention, optimise heart failure therapies, and discuss advanced care planning, an area where Australian practice has embraced structured conversations earlier in the disease trajectory than in many other healthcare systems.

Outcomes, complications, and future directions

Published outcomes consistently show improvements in left ventricular ejection fraction, exercise capacity, and quality of life following AV node ablation with His bundle pacing in persistent atrial fibrillation. The reduction in heart failure hospitalisations is particularly striking in patients with tachycardia-mediated cardiomyopathy. Complication rates are low but include lead dislodgement, generator pocket infection, and rare instances of complete heart block that exceed the safety margins of the device.

Looking ahead, the field is moving toward more physiological pacing targets, including left bundle branch area pacing and, in selected centres, conduction system pacing combined with novel ablative technologies. Australian operators are increasingly involved in international registries, contributing data on patient selection and long-term outcomes. For clinicians and patients who want a clearer sense of how percentage-based outcomes are reported across different domains, it can be instructive to compare live casino RTP figures, which apply the same percentage-return language to a very different context. The procedure is not a first-line rhythm strategy but a powerful tool when thoughtfully deployed. Patients should be counselled about the lifelong commitment to pacing and the realistic expectations for symptom relief, exercise tolerance, and cardiac function recovery.

If you are an Australian clinician looking to contribute to the literature or share procedural insights with the regional electrophysiology community, consider submitting your original research, case series, or technique review to the journal. Open-access publication ensures your work reaches clinicians across the Asia-Pacific region and beyond, supporting the shared goal of better outcomes for patients living with atrial fibrillation.