title: Usefulness of myocardial contrast echocardiographic quantification of risk area for predicting postprocedural complications in patients undergoing septal ethanol ablation for obstructive hypertrophic cardiomyopathy.
abstract: Septal ethanol ablation (SEA) is an alternative to surgical myectomy in patients who have drug-refractory obstructive hypertrophic cardiomyopathy. However, permanent atrioventricular conduction block is seen more frequently with SEA. To determine whether septal infarction risk area (SIRA) predicts outcome in patients who have obstructive hypertrophic cardiomyopathy and are undergoing SEA, we evaluated 51 patients (mean age 60 +/- 16, 53% women) who had a successful SEA at Toronto General Hospital (November 1998 to June 2003). Intracoronary myocardial contrast echocardiography that targeted the contact area between the septum and the anterior mitral leaflet was performed before ethanol injection. End-systolic myocardial contrast echocardiographic frames were color coded for better delineation of contrast borders, and myocardial contrast echocardiographic area was calculated by planimetry. Patients were assigned to 1 of 2 groups by median SIRA value (3.51 cm(2), range 0.4 to 7.8). The 2 groups did not differ significantly in age, medication before SEA, electrocardiographic characteristics, left ventricular function, left atrial diameter, volume of intracoronary ethanol injected, peak creatine kinase after ablation, and baseline and follow-up left ventricular outflow tract gradients at rest. Patients in the large SIRA group had greater hypertrophy and a larger septal artery than did patients in the small SIRA group. In the small SIRA group, 3 patients (11.5%) had pacemaker implantation; in the large SIRA group, 12 patients (48.0%) had complications after SEA (pacemaker in 5 patients, implantable defibrillator in 5 patients, death in 2 patients; p = 0.008). We conclude that patients who have hypertrophic cardiomyopathy with a small, well-localized SIRA benefit similarly from SEA as patients who have a larger SIRA but with significantly fewer serious complications.
authors.affiliation: Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Daniel
authors.initials: D
authors.lastname: Monakier
authors.forename: Anna
authors.initials: A
authors.lastname: Woo
authors.forename: Timothy
authors.initials: T
authors.lastname: Puri
authors.forename: Leonard
authors.initials: L
authors.lastname: Schwartz
authors.forename: John
authors.initials: J
authors.lastname: Ross
authors.forename: Michal
authors.initials: M
authors.lastname: Jamorski
authors.forename: Hua
authors.initials: H
authors.lastname: Yang
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.forename: Mani
authors.initials: M
authors.lastname: Vannan
authors.forename: E Douglas
authors.initials: ED
authors.lastname: Wigle
authors.forename: Harry
authors.initials: H
authors.lastname: Rakowski
mesh_terms: D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D017115:Catheter Ablation / Q000009:adverse effects*; D017147:Defibrillators, Implantable; D004452:Echocardiography / Q000379:methods; D000431:Ethanol / Q000008:administration & dosage; D005260:Female; D006327:Heart Block / Q000000981:diagnostic imaging / Q000209:etiology; D006346:Heart Septum / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000209:etiology; D010138:Pacemaker, Artificial; D016896:Treatment Outcome
chemical_list: D000431:Ethanol