Quantitative Dual Energy Computed Tomography in Pulmonary Hypertension
Condition: Pulmonary Hypertension
MeSH terms: Hypertension, Pulmonary; Hypertension
Study type: Interventional

Summary: 
      Pathophysiological mechanisms leading to pulmonary hypertension (PH) are complex.
      Quantitative computed tomography (QCT) can help us to study morphological alterations in
      patients with PH. These CT morphometrics are useful to predict the degree of PH severity at
      least in PH secondary to chronic obstructive pulmonary disease (COPD). We hypothesized that
      assessing lung perfusion using dual energy CT (DECT) can refine our knowledge on PH
      pathophysiology and help to predict PH severity irrespective of its etiology
    

Detailed description: 
      Pulmonary hypertension (PH) is a serious disease with poor prognosis and high morbidity and
      mortality. It is defined as an increase in mean pulmonary arterial pressure (mPAP) above or
      equal to 25 mmHg measured by right heart catheterization, which is an invasive technique.

      Computed tomography (CT) plays an important role in the classification of PH and the
      identification of pulmonary etiologies responsible for PH (chronic obstructive pulmonary
      disease (COPD), idiopathic pulmonary fibrosis...) or signs of chronic thromboembolic PH
      (CTEPH).

      Quantitative CT allows accurate analysis of the morphological changes found in PH and leading
      to a better understanding of the complex interactions involved (arterial and bronchial
      remodeling in PH secondary to COPD, inflammation etc.).

      Dual energy CT acquisition has shown its interest in helping to diagnose pulmonary embolism.
      It provides information on pulmonary perfusion by performing iodine mapping and measuring
      pulmonary perfusion blood volume (PVB).

      This project intends to study morphological and functional alterations at bronchial and
      vascular levels in PH patients using quantitative DECT and to examine their impact to predict
      existence and severity of PH irrespective of its etiology. To measure from DECT scan images,
      cross sectional area of small pulmonary vessels (CSA), bronchial wall thickness (WT) and
      pulmonary perfusion blood volume. To collect data from right heart catheterization,
      echocardiography, pulmonary functional tests and blood tests. All these examinations will be
      performed in routine care within a week after the patient is referred to our institution.
      Statistical analysis of these parameters could lead to a multivariate model able to predict
      existence and severity of PH.

      In addition, DECT allows the use of low energy (low Kilovoltage), which increases contrast
      and improves segmentation of the pulmonary arteries. Thus, peripheral pulmonary arteries and
      veins can be distinguishable in order to evaluate not just the sectional area of the small
      pulmonary vessels but also 3D volume of small pulmonary arteries (VSA). This technical
      modification would make it possible to refine the quantitative exploration of the vascular
      compartment of PH
    

Intervention name(s): dual energy CT scans
Intervention type(s): Other
Intervention description(s): The procedure involves post processing and analysis of reconstructed images from dual energy CT scans available at the Bordeaux University Hospital and used in routine care, which will allow us to collect morphometric data (bronchial wall thickness and cross sectional area of small pulmonary vessels) and to assess pulmonary perfusion by studying iodine mapping and quantifying pulmonary perfusion blood volume (PVB)
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: pulmonary hypertension; dual energy CT; quantification; lung perfusion; prediction