title: Anatomic relationships between the coronary venous system, surrounding structures, and the site of origin of epicardial ventricular arrhythmias.
abstract: BACKGROUND
  Epicardial left ventricular (LV) idiopathic ventricular arrhythmias (VAs) can be approached via the pericardial space, the coronary venous system (CVS), or other surrounding structures. The anatomic relationships between epicardial sites of origin (SOO) of VAs and surrounding anatomic structures have not been systematically described.
  
  
  RESULTS
  In 17 patients with idiopathic epicardial VAs, the relationships between the SOO and the CVS and other neighboring anatomic structures were assessed by computed tomographic angiography. Ablation was successful in 12/17 patients (71%). In 10/17 patients, the SOO was at a distance of ≤4 mm from a coronary artery. The SOO was closer to the CVS (2.1 ± 1.5 mm) than to the pericardial space (9.7 ± 3.7 mm) or the LV endocardium (7.7 ± 2.7 mm). Successful ablations were carried out from the CVS (n = 3), the CVS and LV endocardium (n = 5), the CVS and the aortic cusp (n = 1), the CVS, the LV endocardium, and the aortic cusp (n = 1), the LV endocardium (n = 1), and the CVS and the pericardial space (n = 1). In the remaining 5 patients, a subxyphoid pericardial ablation procedure was attempted and failed in all 5 patients.
  
  
  CONCLUSIONS
  The CVS is closer to the SOO of epicardial idiopathic VAs than the pericardial space, the ventricular endocardium, and the aortic cusps. Given the proximity to coronary arteries at the SOO, radiofrequency energy often cannot be safely delivered to eliminate a VA and ablation may also need to be performed from adjacent structures. A subxyphoid pericardial ablation procedure has a low probability of success in patients with idiopathic epicardial VAs.
authors: Division of Cardiovascular Medicine and Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA.
authors: Thomas P
authors: TP
authors: Carrigan
authors: Smita
authors: S
authors: Patel
authors: Miki
authors: M
authors: Yokokawa
authors: Eric
authors: E
authors: Schmidlin
authors: Scott
authors: S
authors: Swanson
authors: Fred
authors: F
authors: Morady
authors: Frank
authors: F
authors: Bogun
mesh_terms: D017023:Coronary Angiography / Q000379:methods; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000601:surgery; D005260:Female; D006329:Heart Conduction System / Q000000981:diagnostic imaging* / Q000601:surgery; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D010496:Pericardium / Q000000981:diagnostic imaging* / Q000601:surgery*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017180:Tachycardia, Ventricular / Q000000981:diagnostic imaging* / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome
keywords: catheter ablation; coronary venous system; epicardial ablation; idiopathic ventricular tachycardia; ventricular tachycardia