title: Non-invasive estimation of pulmonary vascular resistance in patients of pulmonary hypertension in congenital heart disease with unobstructed pulmonary flow.
abstract: BACKGROUND
  Pulmonary vascular resistance (PVR) is a critical and essential parameter during the assessment and selection of modality of treatment in patients with congenital heart disease accompanied by pulmonary arterial hypertension.
  
  
  OBJECTIVE
  The present study was planned to evaluate non-invasive echocardiographic parameters to assess pulmonary vascular resistance.
  
  
  METHODS
  This prospective observational study included 44 patients admitted in the cardiology and pediatric cardiology ward of our institution for diagnostic or pre-operative catheter based evaluation of pulmonary arterial pressure and PVR.
  
  
  METHODS
  Detailed echocardiographic evaluation was carried out including tricuspid regurgitation velocity (TRV) and velocity time integral of the right-ventricular outflow tract (VTIRVOT). These parameters were correlated with catheter-based measurements of PVR.
  
  
  RESULTS
  The TRV/VTIRVOT ratio correlated well with PVR measured at catheterization (PVRcath) (r = 0.896, 95% confidence interval [CI] 0.816 to 0.9423, P < 0.001). Using the Bland-Altman analysis, PVR measurements derived from Doppler data showed satisfactory limits of agreement with catheterization estimated PVR. For a PVR of 6 Wood units (WU), a TRV/VTIRVOT value of 0.14 provided a sensitivity of 96.67% and a specificity of 92.86% (area under the curve 0.963, 95% confidence interval 0.858 to 0.997) and for PVR of 8 WU a TRV/VTIRVOT value of 0.17 provided a sensitivity of 79.17% and a specificity of 95% (area under the curve 0. 0.923, 95% confidence interval 0.801 to 0.982).
  
  
  CONCLUSIONS
  Doppler-derived ratio of TRV/VTIRVOT is a simple, non-invasive index, which can be used to estimate PVR.
authors.affiliation: Department of Cardiology, Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.
authors.forename: Arindam
authors.initials: A
authors.lastname: Pande
authors.affiliation: Associate Professor of Cardiology and Incharge - Pediatric Cardiology Unit, Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.
authors.forename: Achyut
authors.initials: A
authors.lastname: Sarkar
authors.affiliation: Department of Cardiology, Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.
authors.forename: Imran
authors.initials: I
authors.lastname: Ahmed
authors.affiliation: Assistant Professor, Kasturba Medical College, Manipal, Karnataka, India.
authors.forename: Gs
authors.initials: G
authors.lastname: Naveen Chandra
authors.affiliation: Department of Cardiology, Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.
authors.forename: Shailesh Kumar
authors.initials: SK
authors.lastname: Patil
authors.affiliation: Department of Cardiology, Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.
authors.forename: Chanchal Kumar
authors.initials: CK
authors.lastname: Kundu
authors.affiliation: Department of Cardiology, Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.
authors.forename: Rahul
authors.initials: R
authors.lastname: Arora
authors.affiliation: Associate Professor of Cardiology and Incharge - Pediatric Cardiology Unit, Institute of Post-Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.
authors.forename: Ajanta
authors.initials: A
authors.lastname: Samanta
keywords: Pulmonary vascular resistance; noninvasive assessment; pulmonary arterial hypertension; tricuspid regurgitation velocity; velocity time integral