Catheter ablation of atrial fibrillation in HFpEF

Atrial fibrillation is the most common sustained cardiac arrhythmia managed by Australian cardiologists, with prevalence climbing steadily in communities along the eastern seaboard from Cairns to Hobart. The overlap between AF and heart failure with preserved ejection fraction (HFpEF) has emerged as one of the most pressing problems in modern cardiac care, particularly given the aging demographic profile documented by the Australian Institute of Health and Welfare. Patients with HFpEF develop atrial fibrillation at higher rates than the general population, and once AF is present, symptoms worsen, hospitalisations increase, and quality of life deteriorates. For clinicians weighing the role of catheter ablation in this population, the evidence base has matured considerably in recent years, although important questions about patient selection and durability of benefit remain.

Catheter ablation, principally through pulmonary vein isolation, has become an established rhythm-control strategy for symptomatic AF. Whether the same benefit translates to patients with HFpEF has long been debated, as early landmark trials in heart failure focused predominantly on individuals with reduced ejection fraction. Newer studies, registry data, and meta-analyses are now clarifying who should be referred, what outcomes can realistically be achieved, and how Australian electrophysiology laboratories should approach these often-complex procedures.

Pathophysiology of AF in the HFpEF substrate

HFpEF is characterised by impaired left ventricular relaxation, elevated filling pressures, and a stiff, non-compliant ventricle. These haemodynamic features translate directly into the left atrium, where chronic pressure overload drives chamber dilation, interstitial fibrosis, and electrical remodelling. The result is a substrate primed to initiate and sustain atrial fibrillation. In many Australian patients this pathway is amplified by coexisting conditions such as obesity, hypertension, sleep-disordered breathing, and type 2 diabetes, each of which contributes to systemic inflammation and atrial myopathy.

The interplay between diastolic dysfunction and AF is bidirectional. Episodes of AF reduce atrial contractility and ventricular filling time, raising left atrial pressure further and worsening pulmonary congestion. Over months, this cycle accelerates the progression of both conditions. Understanding this bidirectional relationship is essential when deciding whether catheter ablation is likely to break the cycle or simply palliate symptoms in a patient with advanced atrial myopathy, and it underpins much of the contemporary rationale for earlier intervention.

Evidence supporting ablation in HFpEF

Several observational series and small randomised trials have examined catheter ablation outcomes specifically in patients with HFpEF. Although early studies were limited by heterogeneous definitions and short follow-up, more recent publications suggest that freedom from atrial arrhythmia is achievable in carefully selected patients, with rates comparable to those without heart failure when procedures are performed in high-volume centres.

A 2022 meta-analysis pooling data from multiple cohorts found that patients with HFpEF undergoing AF ablation experienced meaningful improvements in functional capacity, N-terminal pro-B-type natriuretic peptide levels, and echocardiographic parameters of diastolic function compared with those managed medically. Sinus rhythm maintenance at twelve months was lower than in patients with normal hearts but still exceeded 50 percent in most series. The challenge remains identifying which HFpEF patients will derive the greatest absolute benefit, given that procedural risks rise with greater comorbidity burden. Readers interested in the broader procedural context of complex ablation can review epicardial ablation access, which shares several technical considerations relevant to patients with structural heart disease.

Procedural considerations and technical challenges

Ablation in the setting of HFpEF demands more than the routine pulmonary vein isolation performed in otherwise healthy patients. Left atrial pressures are frequently elevated, predisposing to pulmonary oedema during or shortly after the procedure. Many Australian electrophysiologists therefore stage procedures, limit intra-operative fluid administration, and use proactive diuresis during long cases. General anaesthesia, commonly employed at centres including Royal Melbourne Hospital and Westmead, must be carefully titrated because patients with diastolic dysfunction tolerate reduced preload poorly.

Mapping strategies may need to extend beyond the pulmonary veins. In patients with extensive atrial fibrosis, as assessed by late gadolinium enhancement cardiac MRI or low-voltage areas on electroanatomical mapping, additional ablation of posterior wall, roof lines, or non-PV triggers may improve outcomes. However, the risk of atrial oesophageal fistula and phrenic nerve injury increases with extensive ablation, and operators must balance the desire for durable rhythm control against the morbidity of complications. For an overview of contemporary ablation strategies and emerging techniques, the journal article archive provides a useful collection of recent reviews and original research relevant to this patient group.

Patient selection and the Australian practice environment

Selecting the right candidate is as important as the procedure itself. The patients most likely to benefit from catheter ablation for AF in HFpEF are those with symptomatic, paroxysmal or short-standing persistent AF, modest atrial dilation, limited comorbidity, and the ability to tolerate long-term anticoagulation. Those with long-standing persistent AF, severe left atrial enlargement, or uncontrolled pulmonary hypertension tend to have higher recurrence rates and should be counselled accordingly. A multidisciplinary heart failure team assessment, ideally involving a heart failure cardiologist, an electrophysiologist, and often a cardiac advanced-practice nurse, helps ensure that underlying contributors such as uncontrolled hypertension, sleep apnoea, or obesity are addressed before and after ablation.

In Australia, catheter ablation for AF is funded through the Medicare Benefits Schedule, although rebates have not always kept pace with the costs of advanced three-dimensional mapping systems and single-shot technologies. Public hospital waiting lists in cities such as Brisbane and Adelaide can stretch beyond twelve months, prompting many patients to seek care in private laboratories. Workforce capacity is also a consideration: the number of certified electrophysiologists per capita remains lower than in many comparable OECD nations, and training fellowships at institutions such as the Baker Heart and Diabetes Institute in Melbourne are working to address this gap. Patients considering ablation are encouraged to discuss expected recovery, repeat procedure rates, and long-term medication needs with their treating team before committing to intervention.

Future directions and ongoing research

Several randomised trials currently enrolling patients will help define the role of catheter ablation in HFpEF more precisely. Studies are testing whether early rhythm control, delivered before extensive atrial remodelling occurs, can prevent progression of HFpEF and reduce heart failure hospitalisations. Adjunctive therapies, including SGLT2 inhibitors, which have shown favourable effects on atrial remodelling in substudies of large heart failure trials, are being evaluated as enhancers of ablation success. Weight loss and structured exercise programs, already a focus of Australian cardiac rehabilitation services, may also improve long-term outcomes when combined with ablation.

For clinicians and researchers contributing to this evolving field, the submission guidelines outline pathways for case reports, original research, and review articles that will continue to refine how AF ablation is offered to patients with HFpEF. As the evidence matures, Australian centres are well placed to lead multi-site registries and pragmatic trials, given the relatively concentrated population and integrated electronic health records in many regions of the country.

Patients with HFpEF and atrial fibrillation deserve a thoughtful, individualised approach to rhythm management. Catheter ablation is no longer a therapy reserved only for those with structurally normal hearts; when applied to carefully selected patients with HFpEF, it can restore sinus rhythm, improve symptoms, and potentially alter the trajectory of heart failure. Clinicians across Australia are encouraged to refer suitable patients to high-volume electrophysiology centres early, rather than reserving ablation as a last resort after years of medical therapy and progressive atrial remodelling.