title: New pulmonary vein Doppler echocardiographic index predicts significant interatrial shunting in secundum atrial septal defect.
abstract: BACKGROUND
  The relation between pulmonary venous flow (PVF) pattern and degree of left-to-right interatrial shunting (IAS) in patients with secundum atrial septal defect (ASD) is unknown.
  
  
  METHODS
  Fifty consecutive ASD patients (14 males, 36 ± 17 years) received transthoracic echocardiography (TTE) before and 1 day after transcatheter closure and their results were compared to 40 controls. The ratio of pulmonary-to-systemic flows (Qp/Qs) was assessed by TTE and invasive oximetry.
  
  
  RESULTS
  Pre-closure PV systolic (PVs), diastolic (PVd) velocities and velocity-time integral (PV-VTI) increased, time from onset of ECG Q-wave to the peak PV diastolic wave (Q-PVd) shortened and atrial reversal (PVar) velocity significantly decreased as compared to normals. These findings normalized after closure. Patients with large IAS (defined as invasive Qp/Qs ≥ 2) had higher PVs, PVd and PV-VTI, shorter Q-PVd but lower PVar (all p<0.01) than those with small IAS. Invasive Qp/Qs ratios correlated with PVs, PVd, PV-VTI, Q-PVd and TTE-derived Qp/Qs ratios, ASD sizes and RV end-diastolic dimensions (all p<0.05). PV-VTI (β=0.49) and ASD size (β=0.48) remained independent predictors of large IAS after multivariate analysis. The corresponding sensitivity, specificity and AUC were 89%, 82% and 0.90 respectively for a PV-VTI of 30 cm (p<0.001).
  
  
  CONCLUSIONS
  ASD patients with significant IAS have distinguishable PVF features. Doppler evaluation of PV-VTI is a novel additional tool for assessing the magnitude of shunting in these patients non-invasively.
authors.affiliation: Division of Cardiology, Department of Medicine and Therapeutics, Prince of Wales Hospital, Li Ka Shing Institute of Health and Sciences, Institute of Vascular Medicine, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Yat-Yin
authors.initials: YY
authors.lastname: Lam
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
authors.forename: Gabriel Wai-Kwok
authors.initials: GW
authors.lastname: Yip
authors.forename: Zhi-An
authors.initials: ZA
authors.lastname: Li
authors.forename: Ya
authors.initials: Y
authors.lastname: Yang
authors.forename: Cheuk-Man
authors.initials: CM
authors.lastname: Yu
mesh_terms: D001783:Blood Flow Velocity; D015150:Echocardiography, Doppler; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D011667:Pulmonary Veins / Q000000981:diagnostic imaging / Q000503:physiopathology*; D012720:Severity of Illness Index