title: Preimplant left ventricular end-diastolic dimension and body weight independently associate with paced QRS duration in patients receiving right ventricular apical pacing for complete atrioventricular block.
abstract: BACKGROUND
  Paced QRS duration, a good marker of ventricular asynchrony while pacing, has been accepted as a valuable predictor of new-onset heart failure in patients receiving right ventricular apical pacing. But nowadays we have little evidence for predicting paced QRS duration before the implantation.
  
  
  OBJECTIVE
  There might be relationships between paced QRS duration and demographic characteristics, clinical features such as comorbidities, native QRS duration, or preimplant cardiac size. The purpose of this article was to identify potential predictors of paced QRS duration in patients receiving right ventricular apical pacing for complete atrioventricular block.
  
  
  METHODS
  One hundred seventy patients with right ventricular apical pacing for complete atrioventricular block were divided into 2 groups according to whether the paced QRS duration was longer than 170 ms or not. Demographic characteristics, clinical features, electrocardiogram and echocardiography before implantation, and electrocardiogram immediately after implantation, were retrospectively recorded.
  
  
  RESULTS
  Preimplant left ventricular end-diastolic dimension (LVEDD) and body weight were found to be independently associated with the paced QRS duration. Although both of them had low sensitivity and specificity in predicting paced QRS duration longer than 170 ms, the specificity could increase to 81.2% when they were combined.
  
  
  CONCLUSIONS
  Both preimplant LVEDD and body weight independently associate with paced QRS duration in patients receiving apical pacing for complete atrioventricular block. Although whether they really have an effect on new-onset heart failure still needs to be verified, and these findings might be a good indication.
authors.affiliation: Centre of Arrhythmia Diagnosis and Treatment, Fuwai Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Qiao
authors.forename: Wei
authors.initials: W
authors.lastname: Hua
authors.forename: Shu
authors.initials: S
authors.lastname: Zhang
mesh_terms: D000200:Action Potentials; D000328:Adult; D000368:Aged; D054537:Atrioventricular Block / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D001835:Body Weight; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects* / Q000379:methods; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006333:Heart Failure / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000209:etiology* / Q000503:physiopathology; D016277:Ventricular Function, Left