The University of Manchester Research Atrial Tachycardia Arising From the Crista Terminalis, Detailed Electrophysiological Features and Long-Term Ablation Outcomes DOI: 10.1016/j.jacep.2019.01.014 Document Version Accepted author manuscript Link to publication record in Manchester Research Explorer Citation for published version (APA): Morris, G. M., Segan, L., Wong, G., Wynn, G., Watts, T., Heck, P., Walters, T. E., Nisbet, A., Sparks, P., Morton, J. B., Kistler, P. M., & Kalman, J. M. (2019). Atrial Tachycardia Arising From the Crista Terminalis, Detailed Electrophysiological Features and Long-Term Ablation Outcomes. JACC: Clinical Electrophysiology, 5(4), 448-458. https://doi.org/10.1016/j.jacep.2019.01.014 Published in: JACC: Clinical Electrophysiology Citing this paper Please note that where the full-text provided on Manchester Research Explorer is the Author Accepted Manuscript or Proof version this may differ from the final Published version. If citing, it is advised that you check and use the publisher's definitive version. General rights Copyright and moral rights for the publications made accessible in the Research Explorer are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Takedown policy If you believe that this document breaches copyright please refer to the University of Manchester’s Takedown Procedures [http://man.ac.uk/04Y6Bo] or contact [email protected] providing relevant details, so we can investigate your claim. Download date:09. Oct. 2021 JACC: CLINICAL ELECTROPHYSIOLOGY VOL. - ,NO.- ,2019 ª 2019 PUBLISHED BY ELSEVIER ON BEHALF OF THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION Atrial Tachycardia Arising From the Crista Terminalis, Detailed Electrophysiological Features and Long-Term Ablation Outcomes a,b a a a Gwilym M. Morris, BMBCH,PHD, Louise Segan, MBBS, Geoff Wong, MBBS, Gareth Wynn, MBCHB, MD(RES), a a a a Troy Watts, BSC, Patrick Heck, BMBCH, DM, Tomos E. Walters, MBBS, PHD, Ashley Nisbet, MBCHB, PHD, a a c,d,e Paul Sparks, MBBS, PHD, Joseph B. Morton, MBBS, PHD, Peter M. Kistler, MBBS, PHD, a,c Jonathan M. Kalman, MBBS, PHD ABSTRACT OBJECTIVES The goal of this study was to characterize, in detail, focal atrial tachycardia (AT) arising from the crista terminalis to investigate associations with other atrial arrhythmia and to define long-term ablation outcomes. BACKGROUND The crista terminalis is known to be the most common site of origin for focal AT, but it is not well characterized. METHODS This study retrospectively identified a total of 548 ablation procedures for AT performed at a single center over a 16-year period, of which 171 were arising from the crista terminalis. RESULTS Compared with patients with other AT sites of origin, crista terminalis AT patients were older (57.3 vs. 47.3 years), more commonly female (72.9% vs. 59.1%), were more commonly associated with coexistent atrioventricular nodal re-entry tachycardia (17.1% vs. 9.7%), and were more likely to be inducible with programmed stimulation (81.5% vs. 58.9%). There was preferential conduction in the superior-inferior axis along the crista terminalis. Acute ablation success rate was high (92.2%) and improved significantly when three-dimensional mapping was used (98.5%). Recur- rence in the first 12 months after a successful ablation was 9.7%. Only 2 patients developed atrial fibrillation over the long-term follow-up of >7 years. CONCLUSIONS This large series characterized the clinical and electrophysiological features and immediate and long- term ablation outcomes for AT originating from the crista terminalis. Features of the tachycardia suggest that age-related localized remodeling of the crista terminalis causes a superficial endocardial zone of conduction slowing leading to re- entry. Ablation outcomes were good, with long-term freedom from atrial arrhythmia. (J Am Coll Cardiol EP 2019;- :-–-) © 2019 Published by Elsevier on behalf of the American College of Cardiology Foundation. ocal atrial tachycardia (AT) is an important, the atria but cluster at stereotypical anatomic sites. F although uncommon, cause of supraventricu- The most common site is the crista terminalis (2), lar tachycardia (SVT) accounting for w15% of originally reported as a site of origin for focal tachy- all SVT (1). AT does not occur randomly throughout cardia in a series of 18 patients with excellent acute From the aDepartment of Cardiology, Royal Melbourne Hospital, Melbourne, Australia; bDivision of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; cFaculty of Medicine, Dentistry, and Health Sciences, University of Melbourne, Parkville, Victoria, Australia; dDepartment of Cardiology, The Alfred Hospital, Melbourne, Australia; and the eBaker IDI Heart and Diabetes Institute, Melbourne, Australia. Dr. Morris is supported by a British Heart Foundation Intermediate Fellowship. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. William Steveson, MD, served as Guest Editor for this paper. All authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ in- stitutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the JACC: Clinical Electrophysiology author instructions page. Manuscript received August 30, 2018; revised manuscript received January 15, 2019, accepted January 18, 2019. ISSN 2405-500X/$36.00 https://doi.org/10.1016/j.jacep.2019.01.014 FLA 5.5.0 DTD JACEP863_proof 13 March 2019 7:08 am ce 2 Morris et al. JACC: CLINICAL ELECTROPHYSIOLOGY VOL. - ,NO.- ,2019 Crista Terminalis Atrial Tachycardia - 2019:- – - ABBREVIATIONS success rates (3).Otherstudiessincethen attempted; this approach was followed by isoproter- AND ACRONYMS have confirmed that the crista terminalis re- enol infusion at 1 to 6 mg/min if PES was unsuccessful mains the most common site of origin for alone. Analysis of the mode of initiation (sponta- 3D = three-dimensional focal AT (2). However, since that original neous, including incessant or requiring PES) and AF = atrial fibrillation publication almost 20 years ago, no studies, requirement for isoproterenol were performed ac- AT = atrial tachycardia to the best of our knowledge, have focused cording to anatomic site. Mapping and ablation of the AVNRT = atrioventricular on the clinical and electrophysiological fea- earliest site of endocardial activity relative to the nodal re-entry tachycardia tures of this tachycardia or ablation outcomes onset of the surface P wave was performed with a 3.5- ECG = electrocardiogram in a large series with long-term follow-up. mm open irrigated catheter or a 4-mm solid tip PES = programmed extra catheter. Bipolar intracardiac electrograms were stimulation METHODS filtered at 30 and 500 Hz, and recorded and stored RAA = right atrial appendage digitally on a computerized system simultaneously SVT = supraventricular STUDY POPULATION. The catheter ablation along with the 12-lead surface electrocardiograms. tachycardia database at the Royal Melbourne Hospital Off-line analysis was performed by using on-screen was examined for patients undergoing ablation of digital calipers at 200 mm/s speed. focal AT between the years 1998 and 2014. All pa- MAPPING OF AT. Localization of the AT was per- tients undergoing ablation of AT were included in this formed during tachycardia or atrial ectopy by analysis series and classified according to the anatomic site of of surface electrocardiogram P-wave morphology, successful ablation, or earliest mapped activation if atrial endocardial activation sequence during tachy- ablation was unsuccessful or not attempted. This cardia, and point mapping to locate the site of earliest analysis was a study of patients with focal AT and endocardial activation relative to surface P-wave other mechanisms of SVT; patients with previous onset (Figure 2). Electrograms were classified as ablations for atrial flutteroratrialfibrillation (AF) fractionated if they were >50 ms in duration with >3 were excluded. Detailed analysis of the patients with deviations from baseline, and as a double potential if crista terminalis AT was performed, and data for there were 2 deflections with an isoelectric segment other AT (non–crista terminalis AT) were used as a >30 ms in-between. 3D electroanatomic mapping comparator when required. using CARTO (Biosense Webster, Diamond Bar, Cali- ELECTROPHYSIOLOGICAL STUDY. Patients under- fornia) or NavX (St. Jude Medical, St. Paul, Minne- went a clinically indicated electrophysiology study sota) was used according to operator preference. This and radiofrequency ablation after providing written approach evolved over the time course of the study, informed consent. Patients were studied in the fasted and in the latter half of the period has been the awake state with minimal sedation. Antiarrhythmic standard. Conduction velocity was calculated from drugs were withheld for at least 5 half-lives before the the electroanatomic map across 5 point pairs starting electrophysiology study. from the point of earliest activation. Catheter positioning and study techniques used for RADIOFREQUENCY ABLATION. At operator discre- focal AT ablation have been previously described (4), tion (but in the majority