title: Reappraisal and new observations on atrial tachycardia ablated from the non-coronary aortic sinus of Valsalva.
abstract: The clinical characteristics of atrial tachycardias (AT) ablated from the non-coronary aortic sinus (NCS) are thus far described only in small series. We aimed to outline, in a large cohort of patients, the clinical, electrocardiographic, electrophysiological characteristics of this tachycardia.
  
  
  
  We analysed data pertaining to clinical, electrocardiographic, and electrophysiological characteristics of 43 consecutive patients from an overall cohort of 441 with AT who were successfully ablated from the NCS. The tachycardias ablated from the NCS were paroxysmal (98%) and adenosine sensitive (35/35). The patients were aged 54.6 ± 12.4 years, showing female preponderance (74%). No P wave pattern was predictive of the location of ablation. Electrophysiological findings suggested a possible micro-reentrant mechanism. During tachycardia, atrial electrograms recorded in the NCS preceded the A in the His region by 10.9 ± 7.4 ms. Fractionated atrial electrograms were noted at the site of ablation in 42 patients during the tachycardia. Radiofrequency ablation terminated the tachycardia within 5 s in 88%, with thermal automaticity seen only in 3 patients. The site of ablation at the base of the NCS was adjacent to the presumed site of the retroaortic node, a remnant of the initial atrio-ventricular canal musculature.
  
  
  
  AT ablated from the NCS is a paroxysmal arrhythmia in middle-aged women, with distinct electrocardiographic and electrophysiological characteristics. We suspect the retroaortic node to be involved in the tachycardia circuit.
authors.affiliation: Department of Cardiology, UN Mehta Institute of Cardiology and Research Centre, Civil hospital campus, Asarwa, Ahmedabad, Gujarat, India.|Baroda Heart Institute and Research Centre, Vadodara, India.
authors.forename: Shomu
authors.initials: S
authors.lastname: Bohora
authors.affiliation: Department of Cardiology, UN Mehta Institute of Cardiology and Research Centre, Civil hospital campus, Asarwa, Ahmedabad, Gujarat, India.|Arrhythmia Associates, Mumbai, India.
authors.forename: Yash
authors.initials: Y
authors.lastname: Lokhandwala
authors.affiliation: Arrhythmia and Electrophysiology Unit, Biocor Instituto, Nova Lima, Brazil.|Pós Graduação Ciências Médicas-MG, Faculdade Ciências Médicas-MG, Belo Horizonte, Brazil.
authors.forename: Eduardo Back
authors.initials: EB
authors.lastname: Sternick
authors.affiliation: Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Anderson
authors.affiliation: Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands.
authors.forename: Hein J J
authors.initials: HJJ
authors.lastname: Wellens
mesh_terms: D000200:Action Potentials; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D018572:Disease-Free Survival; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005060:Europe; D005260:Female; D006339:Heart Rate; D006801:Humans; D007194:India; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012189:Retrospective Studies; D012850:Sinus of Valsalva / Q000503:physiopathology / Q000601:surgery*; D013617:Tachycardia, Supraventricular / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome
keywords: Non-coronary aortic sinus • Aortic sinus of Valsalva • Atrial
                      tachycardia • Catheter ablation • Retroaortic node • Left bundle branch
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