title: Value of the paced QRS duration.
abstract: BACKGROUND
  The value for paced QRS duration (pQRSd) to detect left ventricular (LV) dysfunction in right ventricular apex (RVA)-paced patients has not been evaluated.
  
  
  RESULTS
  A total of 272 RVA-paced patients, including 99 with LV systolic dysfunction (LVSD) and 173 without LVSD, were enrolled in this study. The pQRSd, echocardiographic variables, and plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were measured. Relationships between pQRSd and echocardiographic variables, NT-proBNP levels, and New York Heart Association (NYHA) functional classification were analyzed. pQRSd was correlated with LV end-diastolic and end-systolic dimensions (beta = 1.59 and 1.54, respectively; all P < .001), NT-proBNP levels (beta = 12.98, P < .001) and LV ejection fraction (beta = -109.25, P < .001). There was a stepwise increase in pQRSd with increasing NYHA Class (all P < .001). The pQRSd cutoff value of 200 ms, derived from the receiver operator characteristic curve, had sensitivity of 71.72% and specificity of 86.71% to detect LVSD. pQRSd >or= 240 ms gave a positive predictive value of 100%, whereas <180 ms excluded >97.3% of patients with LVSD.
  
  
  CONCLUSIONS
  In RVA-paced patients, pQRSd is correlated with left ventricular structures and function and pQRSd of 200 ms is a satisfactory cutoff value in terms of sensitivity and specificity for detecting LVSD.
authors.affiliation: Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Wenzhi
authors.initials: W
authors.lastname: Pan
authors.forename: Yangang
authors.initials: Y
authors.lastname: Su
authors.forename: Xue
authors.initials: X
authors.lastname: Gong
authors.forename: Aijun
authors.initials: A
authors.lastname: Sun
authors.forename: Xianhong
authors.initials: X
authors.lastname: Shu
authors.forename: Junbo
authors.initials: J
authors.lastname: Ge
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial / Q000379:methods / Q000592:standards*; D016022:Case-Control Studies; D004452:Echocardiography / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012680:Sensitivity and Specificity; D013318:Stroke Volume / Q000502:physiology; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000503:physiopathology; D016278:Ventricular Function, Right / Q000502:physiology