title: Arrhythmogenic substrate at the interventricular septum as a target site for radiofrequency catheter ablation of recurrent ventricular tachycardia in left dominant arrhythmogenic cardiomyopathy.
abstract: BACKGROUND
  Left dominant arrhythmogenic cardiomyopathy (LDAC) is a rare condition characterised by progressive fibrofatty replacement of the myocardium of the left ventricle (LV) in combination with ventricular arrhythmias of LV origin.
  
  
  METHODS
  A thirty-five-year-old male was referred for evaluation of recurrent sustained monomorphic ventricular tachycardia (VT) of 200 bpm and right bundle branch block (RBBB) morphology. Cardiac magnetic resonance imaging showed late gadolinium enhancement distributed circumferentially in the epicardial layer of the LV free wall myocardium including the rightward portion of the interventricular septum (IVS). The clinical RBBB VT was reproduced during the EP study. Ablation at an LV septum site with absence of abnormal electrograms and a suboptimum pacemap rendered the VT of clinical morphology noninducible. Three other VTs, all of left bundle branch block (LBBB) pattern, were induced by programmed electrical stimulation. The regions corresponding to abnormal electrograms were identified and ablated at the mid-to-apical RV septum and the anteroseptal portion of the right ventricular outflow tract. No abnormalities were found at the RV free wall including the inferolateral peritricuspid annulus region. Histological examination confirmed the presence of abnormal fibrous and adipose tissue with myocyte reduction in endomyocardial samples taken from both the left and right aspects of the IVS.
  
  
  CONCLUSIONS
  LDAC rarely manifests with sustained monomorphic ventricular tachycardia. In this case, several VTs of both RBBB and LBBB morphology were amenable to endocardial radiofrequency catheter ablation.
authors.affiliation: 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, U Nemocnice 2, Prague, 128 08, Czech Republic. stepan.havranek@lf1.cuni.cz.
authors.forename: Stepan
authors.initials: S
authors.lastname: Havranek
authors.affiliation: 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, U Nemocnice 2, Prague, 128 08, Czech Republic. tomas.palecek@vfn.cz.
authors.forename: Tomas
authors.initials: T
authors.lastname: Palecek
authors.affiliation: 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, U Nemocnice 2, Prague, 128 08, Czech Republic. tomas.kovarnik@vfn.cz.
authors.forename: Tomas
authors.initials: T
authors.lastname: Kovarnik
authors.affiliation: Institute of Pathology, First Faculty of Medicine, Charles University and General University Hospital in Prague, Studnickova 2, 128 00, Prague, Czech Republic. ivana.vitkova@vfn.cz.
authors.forename: Ivana
authors.initials: I
authors.lastname: Vitkova
authors.affiliation: 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, U Nemocnice 2, Prague, 128 08, Czech Republic. miroslav.psenicka@vfn.cz.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Psenicka
authors.affiliation: 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, U Nemocnice 2, Prague, 128 08, Czech Republic. ales.linhart@lf1.cuni.cz.
authors.forename: Ales
authors.initials: A
authors.lastname: Linhart
authors.affiliation: Department of Cardiology, Institute for Clinical and Experimental Medicine, Videnska 1958/9, Prague, 140 21, Czech Republic. wichterle@hotmail.com.
authors.forename: Dan
authors.initials: D
authors.lastname: Wichterle
mesh_terms: D000328:Adult; D002037:Bundle-Branch Block / Q000150:complications* / Q000473:pathology / Q000628:therapy*; D009202:Cardiomyopathies / Q000150:complications*; D017115:Catheter Ablation; D004562:Electrocardiography; D006801:Humans; D008297:Male; D012008:Recurrence; D017180:Tachycardia, Ventricular / Q000150:complications* / Q000473:pathology / Q000628:therapy*