title: Diagnostic electrocardiographic dyad criteria of emphysema in left ventricular hypertrophy.
abstract: BACKGROUND
  The electrocardiographic diagnostic dyad of emphysema, namely a combination of the frontal vertical P-vector and a narrow QRS duration, can serve as a quasidiagnostic marker for emphysema, with specificity close to 100%. We postulated that the presence of left ventricular hypertrophy in emphysema may affect the sensitivity of this electrocardiographic criterion given that left ventricular hypertrophy generates prominent left ventricular forces and may increase the QRS duration.
  
  
  METHODS
  We reviewed the electrocardiograms and echocardiograms for 73 patients with emphysema. The patients were divided into two groups based on the presence or absence of echocardiographic evidence of left ventricular hypertrophy. The P-vector, QRS duration, and forced expiratory volume in one second (FEV1) were computed and compared between the two subgroups.
  
  
  RESULTS
  There was no statistically significant difference in qualitative lung function (FEV1) between the subgroups. There was no statistically significant difference in mean P-vector between the subgroups. The mean QRS duration was significantly longer in patients with left ventricular hypertrophy as compared with those without left ventricular hypertrophy.
  
  
  CONCLUSIONS
  The presence of left ventricular hypertrophy may not affect the sensitivity of the P-vector verticalization when used as a lone criterion for diagnosing emphysema. However, the presence of left ventricular hypertrophy may significantly reduce the sensitivity of the electrocardiographic diagnostic dyad in emphysema, as it causes a widening of the QRS duration.
authors.affiliation: Department of Internal Medicine, Saint Vincent Hospital, University of Massachusetts Medical School, Worcester, MA, USA.
authors.forename: Swapnil S
authors.initials: SS
authors.lastname: Lanjewar
authors.forename: Lovely
authors.initials: L
authors.lastname: Chhabra
authors.forename: Vinod K
authors.initials: VK
authors.lastname: Chaubey
authors.forename: Saurabh
authors.initials: S
authors.lastname: Joshi
authors.forename: Ganesh
authors.initials: G
authors.lastname: Kulkarni
authors.forename: Chandrasekhar
authors.initials: C
authors.lastname: Kothagundla
authors.forename: Sudesh
authors.initials: S
authors.lastname: Kaul
authors.forename: David H
authors.initials: DH
authors.lastname: Spodick
mesh_terms: D000368:Aged; D004562:Electrocardiography; D005541:Forced Expiratory Volume; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008168:Lung / Q000503:physiopathology; D008875:Middle Aged; D011237:Predictive Value of Tests; D011656:Pulmonary Emphysema / Q000175:diagnosis* / Q000503:physiopathology; D015203:Reproducibility of Results; D014463:Ultrasonography
keywords: P-vector; QRS duration; chronic obstructive pulmonary disease; electrocardiogram; emphysema; left ventricular hypertrophy