title: Right Atrial Approach for Ablation of Ventricular Arrhythmias Arising From the Left Posterior-Superior Process of the Left Ventricle.
abstract: The posterior-superior process of the left ventricle (PSP-LV) is the most inferior and posterior aspect of the basal LV that extends posteriorly to the plane of the tricuspid valve. The PSP-LV is anatomically adjacent to the inferior and medial aspect of the right atrium (RA). We report a series of patients with ventricular arrhythmias (VAs) arising from the PSP-LV and describe a mapping and ablation approach from the RA guided by intracardiac echocardiography.
  
  
  
  Mapping and ablation of the PSP-LV with an RA approach under intracardiac echocardiography guidance were performed in 5 patients with VAs (aged 44±14 years, 2 males) who had failed ablation attempts from multiple endocardial and epicardial (1 patient) sites. Mapping of the PSP-LV from the adjacent inferomedial RA was performed at sites anatomically opposite to the earliest endocardial site of activation under direct intracardiac echocardiography visualization. From the RA side of the PSP-LV, a small atrial signal and a larger ventricular signal were recorded in each case, with an activation time of 32±7 ms pre-QRS (versus 16±5 ms pre-QRS in the LV endocardium; P=0.068). We were able to capture the LV from these sites. Cryoablation was performed in 2 patients, and radiofrequency was used in the remaining 3 cases. In all patients, ablation from the RA eliminated the arrhythmia. All patients remained free of recurrent VAs after a mean follow-up of 12 (7-16) months. There were no immediate or long-term complications.
  
  
  
  The PSP-LV can be a site of origin of VAs, which can be successfully eliminated from the adjacent RA under direct intracardiac echocardiographic visualization.
authors.affiliation: From the Department of Medicine, Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Santangeli
authors.affiliation: From the Department of Medicine, Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia.
authors.forename: Mathew D
authors.initials: MD
authors.lastname: Hutchinson
authors.affiliation: From the Department of Medicine, Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia.
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Supple
authors.affiliation: From the Department of Medicine, Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Callans
authors.affiliation: From the Department of Medicine, Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia.
authors.forename: Francis E
authors.initials: FE
authors.lastname: Marchlinski
authors.affiliation: From the Department of Medicine, Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia. fermin.garcia@uphs.upenn.edu.
authors.forename: Fermin C
authors.initials: FC
authors.lastname: Garcia
mesh_terms: D000328:Adult; D017115:Catheter Ablation / Q000379:methods*; D004452:Echocardiography; D004562:Electrocardiography; D056149:Epicardial Mapping; D005260:Female; D006325:Heart Atria / Q000503:physiopathology / Q000601:surgery*; D006352:Heart Ventricles / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome
keywords: catheter ablation; echocardiography; endocardium; intracardiac echocardiography; ventricular tachycardia arrhythmia