title: Ventricular tachycardia arising from the aortomitral continuity in structural heart disease: characteristics and therapeutic considerations for an anatomically challenging area of origin.
abstract: BACKGROUND
  The aortomitral continuity (AMC) has been described as a site of origin for ventricular tachycardias (VT) in structurally normal hearts. There is a paucity of data on the contribution of this region to VTs in patients with structural heart disease.
  
  
  RESULTS
  Data from 550 consecutive patients undergoing catheter ablation for VT associated with structural heart disease were reviewed. Twenty-one (3.8%) had a VT involving the peri-AMC region (age, 62.7+/-11 years; median left ventricular ejection fraction, 43.6+/-17%). Structural heart disease was ischemic in 7 (33%), dilated cardiomyopathy in 10 (47.6%), and valvular cardiomyopathy in 4 (19%) patients, respectively. After 1.9+/-0.8 catheter ablation procedures (including 3 transcoronary ethanol ablations) the peri-AMC VT was not inducible in 19 patients. The remaining 2 patients underwent cryosurgical ablation. Our first catheter ablation procedure was less often successful (66.7%) for peri-AMC VTs compared with that for 246 VTs originating from the LV free wall (81.4%, P=0.03). During a mean follow-up of 1.9+/-2.1 years, 12 (57.1%) patients remained free of VT, peri-AMC VT recurred in 7 patients, and 1 patient had recurrent VT from a remote location. Three patients died. Analysis of 50 normal coronary angiograms demonstrated an early septal branch supplying the peri-AMC area in 58% of cases that is a potential target for ethanol ablation.
  
  
  CONCLUSIONS
  VTs involving the peri-AMC region occur in patients with structural heart disease and appear to be more difficult to ablate compared with VTs originating from the free LV wall. This region provides unique challenges for radiofrequency ablation, but cryosurgery and transcoronary alcohol ablation appear feasible in some cases.
authors.affiliation: Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA. dsteven@uke.de
authors.forename: Daniel
authors.initials: D
authors.lastname: Steven
authors.forename: Kurt C
authors.initials: KC
authors.lastname: Roberts-Thomson
authors.forename: Jens
authors.initials: J
authors.lastname: Seiler
authors.forename: Keiichi
authors.initials: K
authors.lastname: Inada
authors.forename: Usha B
authors.initials: UB
authors.lastname: Tedrow
authors.forename: Richard N
authors.initials: RN
authors.lastname: Mitchell
authors.forename: Piotr S
authors.initials: PS
authors.lastname: Sobieszczyk
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Eisenhauer
authors.forename: Gregory S
authors.initials: GS
authors.lastname: Couper
authors.forename: William G
authors.initials: WG
authors.lastname: Stevenson
mesh_terms: D000368:Aged; D001011:Aorta / Q000503:physiopathology; D017115:Catheter Ablation / Q000009:adverse effects; D017023:Coronary Angiography; D003452:Cryosurgery / Q000009:adverse effects; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D000431:Ethanol / Q000008:administration & dosage* / Q000009:adverse effects; D005240:Feasibility Studies; D005260:Female; D006331:Heart Diseases / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000503:physiopathology; D012008:Recurrence; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome
chemical_list: D000431:Ethanol