title: New observation of electrocardiogram during sinus rhythm on the atriofascicular and decremental atrioventricular pathways/clinical perspective: [corrected] terminal QRS [corrected] complex slurring or notching.
abstract: BACKGROUND
  Atriofascicular and decremental atrioventricular pathways are variants of accessory pathways with anterograde decremental conduction properties. They result in typical wide Quantronic Resonance System (QRS) tachycardia of left bundle branch block morphology. Data on the sinus rhythm electrocardiographic characteristics are limited.
  
  
  RESULTS
  Thirty patients with accessory pathways of anterograde decremental conduction properties were studied retrospectively (10 atriofascicular pathways and 20 decremental atrioventricular pathways). All patients had a pre-excited atrioventricular tachycardia with anterograde conduction over anterograde decrementally conducting fiber. Eighteen patients fulfilled criteria of minimal pre-excitation during sinus rhythm before ablation. In 10 patients (33%), delta wave was absent, and the only abnormality was terminal QRS slurring or notching on the ECG. It was mainly in leads I, V5, and V6. After ablation, terminal QRS slurring or notching disappeared in all 10 patients. We also did a survey in a control group comprised of 200 subjects without structural heart disease who were matched for age and sex. Terminal QRS slurring or notching was found in 3%.
  
  
  CONCLUSIONS
  This study showed a high prevalence of terminal QRS slurring or notching in patients with atriofascicular or decremental atrioventricular pathways. It can be the sole manifestation of such accessory pathways during sinus rhythm, and disappearance of terminal slurring or notching can be the only hallmark of successful ablation visible on the surface ECG.
authors: Center for Arrhythmia Diagnosis and Treatment, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors: Zili
authors: Z
authors: Liao
authors: Jian
authors: J
authors: Ma
authors: Jiqiang
authors: J
authors: Hu
authors: Qian
authors: Q
authors: Yang
authors: Shu
authors: S
authors: Zhang
mesh_terms: D058606:Accessory Atrioventricular Bundle / Q000503:physiopathology* / Q000601:surgery; D000241:Adenosine; D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D002304:Cardiac Pacing, Artificial; D017115:Catheter Ablation; D002648:Child; D002681:China; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000241:Adenosine