title: Coupling interval variability differentiates ventricular ectopic complexes arising in the aortic sinus of valsalva and great cardiac vein from other sources: mechanistic and arrhythmic risk implications.
abstract: OBJECTIVE
  The objective of this study was to determine whether premature ventricular contractions (PVCs) arising from the aortic sinuses of Valsalva (SOV) and great cardiac vein (GCV) have coupling interval (CI) characteristics that differentiate them from other ectopic foci.
  
  
  BACKGROUND
  PVCs occur at relatively fixed CI from the preceding normal QRS complex in most patients. However, we observed patients with PVCs originating in unusual areas (SOV and GCV) in whom the PVC CI was highly variable. We hypothesized that PVCs from these areas occur seemingly randomly because of the lack of electrotonic effects of the surrounding myocardium.
  
  
  METHODS
  Seventy-three consecutive patients referred for PVC ablation were assessed. Twelve consecutive PVC CIs were recorded. The ΔCI (maximum - minimum CI) was measured.
  
  
  RESULTS
  We studied 73 patients (age 50 ± 16 years, 47% male). The PVC origin was right ventricular (RV) in 29 (40%), left ventricular (LV) in 17 (23%), SOV in 21 (29%), and GCV in 6 (8%). There was a significant difference between the mean ΔCI of RV/LV PVCs compared with SOV/GCV PVCs (33 ± 15 ms vs. 116 ± 52 ms, p < 0.0001). A ΔCI of >60 ms demonstrated a sensitivity of 89%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 94%. Cardiac events were more common in the SOV/GCV group versus the RV/LV group (7 of 27 [26%] vs. 2 of 46 [4%], p < 0.02).
  
  
  CONCLUSIONS
  ΔCI is more pronounced in PVCs originating from the SOV or GCV. A ΔCI of 60 ms helps discriminate the origin of PVCs before diagnostic electrophysiological study and may be associated with increased frequency of cardiac events.
authors.affiliation: UCLA Cardiac Arrhythmia Center, David Geffen School of Medicine at UCLA, Los Angeles, California.
authors.forename: Jason S
authors.initials: JS
authors.lastname: Bradfield
authors.affiliation: Krannert Institute of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Homsi
authors.affiliation: UCLA Cardiac Arrhythmia Center, David Geffen School of Medicine at UCLA, Los Angeles, California.
authors.forename: Kalyanam
authors.initials: K
authors.lastname: Shivkumar
authors.affiliation: Krannert Institute of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana. Electronic address: jmiller6@iu.edu.
authors.forename: John M
authors.initials: JM
authors.lastname: Miller
mesh_terms: D017115:Catheter Ablation / Q000379:methods*; D003331:Coronary Vessels / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D012850:Sinus of Valsalva / Q000503:physiopathology*; D013318:Stroke Volume / Q000502:physiology*; D016896:Treatment Outcome; D018879:Ventricular Premature Complexes / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery
keywords: aortic sinus of Valsalva; coupling interval; great cardiac vein; premature ventricular contraction