Introduction: Catheter ablation (CA) for the treatment of ventricular arrhythmia (VA) is a complex and evolving field and, in the United Kingdom (UK), in recent years, its use is expanding. Perhaps due to the complex and evolving nature of the procedure, there are many aspects that can be approached in a variety of ways. The threshold to intervene may vary from operator to operator and the techniques that can be used before, during after the procedure are numerous. The purpose of this study was to provide insight into the variances in practice currently being employed for CA of VA across the UK.
Methods: A questionnaire was distributed at the heart rhythm congress (HRCUK) to consultant electrophysiologists currently involved in a VA ablation programme. The questionnaire was designed to provide information on the volume and mixture of cases being undertaken. Data regarding patient selection, drug treatment, mapping and ablation was also collected.
Results: Questionnaires were returned from 14 centres in England. A truncated summary of results is presented. CA was done most frequently in the setting of VA in ischaemic cardiomyopathy, followed by outflow tract tachycardia/normal heart VA, followed by VA in non-ischaemic cardiomyopathy. CA was done rarely in conditions such as Brugada syndrome, arrhythmogenic cardiomyopathy and idiopathic ventricular fibrillation (VF).
With regards pre-procedural approach, 64 % of respondents performed transthoracic echocardiography (TTE) to exclude LV thrombus prior to ablation and 100% would perform CA on warfarin but 14% would not perform on direct oral anticoagulants (DOACs). Forty-two percent would perform ablation in the presence of organised left ventricular thrombus. With regards patient selection, 84% of respondents would perform CA for the first episode of VA in 0–25% of their patients and 16% would perform CA for first episode of VA in 25–50% of their patients.
Thirty percent reported that 26–50% of their patients were on amiodarone, 53% reported that 51–75% of their patients were on amiodarone and 15% reported that 76–100% of their patients were on amiodarone. All but one respondent had on site cardiac surgical cover. When considering the procedure, there were variations in the use of vascular ultrasound for venous access (57% use) and the use of general anaesthesia 14% in 0–25% cases, 14% in 26–50% of cases, 50% in 51–75% of cases and 21% in 76–100% of cases. Seventy-one percent of respondents performed epicardial ablation. Fifty-seven percent routinely perform VT stimulation prior to CA and 35% perform substrate-based ablation only. Ablation end points varied, with 64% aiming to eliminate clinical VT, 42% aiming for substrate homogenisation and 42% aiming to eliminate local abnormal ventricular activities (LAVAs). Fifty percent routinely anticoagulate patients and 64% use DOACs in preference to warfarin.
Conclusion: This small survey has provided insight into the practice of a significant proportion (approximately 40%) of ablation centres in the UK currently performing CA for VA. It demonstrates that there is significant heterogeneity in the way that CA for VT is approached. Amongst other things, it is evident that there are differences in thresholds for intervention, use of anti-arrhythmic drugs and the strategies used when ablating across the country. We believe this highlights the need for a prospective national database to help study procedural details and outcomes.