title: Septal curvature is marker of hemodynamic, anatomical, and electromechanical ventricular interdependence in patients with pulmonary arterial hypertension.
abstract: OBJECTIVE
  The objective of this study was to determine the factors independently associated with septal curvature in patients with pulmonary arterial hypertension (PAH).
  
  
  METHODS
  Eighty-five consecutive patients with PAH who had an echocardiogram and a right heart catheterization within 24 hours of each others were included in the study. Septal curvature was assessed at the mid-papillary level using the eccentricity index (EI). Marked early systolic septal anterior motion was defined as a change in EI > 0.2 between end-diastole and early systole. Inter-ventricular mechanical delay was calculated as the percent time difference between right ventricular (RV) to left ventricular (LV) end-ejection time normalized for the RR interval.
  
  
  RESULTS
  Average age was 45 ± 11 years and the majority of patients were women (75%). Mean right atrial pressure was 11 ± 7 mmHg, mean PAP was 52 ± 13 mmHg, relative RV area 1.8 ± 0.9, and RV fractional area change 24 ± 8%. End-diastolic EI was 1.6 ± 0.4 and systolic EI was 2.5 ± 0.8. On multivariate analysis relative pulmonary pressure, relative RV area, and inter-ventricular mechanical delay were independently associated with systolic EI (R(2) = 0.72, P < 0.001). Independent determinants of diastolic EI included relative RV area and mean PAP (R(2) = 0.69, P < 0.001). A systolic EI >1.08 differentiated patients with PAH from healthy controls with an AUC = 0.99. Patients with early systolic septal anterior motion (44% of subjects) had lower exercise capacity, more extensive ventricular remodeling, and worst ventricular function.
  
  
  CONCLUSIONS
  Septal curvature is a useful marker of structural, hemodynamic, and electromechanical ventricular interdependence in PAH.
authors.affiliation: Division of Cardiovascular Medicine, Department of Medicine, Stanford University, Stanford, California.
authors.forename: Francois
authors.initials: F
authors.lastname: Haddad
authors.forename: Julien
authors.initials: J
authors.lastname: Guihaire
authors.forename: Mehdi
authors.initials: M
authors.lastname: Skhiri
authors.forename: Andre Y
authors.initials: AY
authors.lastname: Denault
authors.forename: Olaf
authors.initials: O
authors.lastname: Mercier
authors.forename: Shadi
authors.initials: S
authors.lastname: Al-Halabi
authors.forename: Bojan
authors.initials: B
authors.lastname: Vrtovec
authors.forename: Elie
authors.initials: E
authors.lastname: Fadel
authors.forename: Roham T
authors.initials: RT
authors.lastname: Zamanian
authors.forename: Ingela
authors.initials: I
authors.lastname: Schnittger
mesh_terms: D001783:Blood Flow Velocity; D001794:Blood Pressure; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006346:Heart Septum / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D018497:Ventricular Dysfunction, Right / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology*
keywords: heart failure; imaging; inter-ventricular dependence; pulmonary hypertension; septum