<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT03806907</url>
  </required_header>
  <id_info>
    <org_study_id>STH20623</org_study_id>
    <nct_id>NCT03806907</nct_id>
  </id_info>
  <brief_title>Iodine Subtraction Mapping in the Diagnosis of Chronic Pulmonary Thromboembolic Disease</brief_title>
  <acronym>INSPIRE</acronym>
  <official_title>IodiNe Subtraction maPpIng in the Diagnosis of chRonic Pulmonary thromboEmbolic Disease (INSPIRE): An Observational Diagnostic Study</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>University of Sheffield</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Sheffield Teaching Hospitals NHS Foundation Trust</agency>
      <agency_class>Other</agency_class>
    </collaborator>
  </sponsors>
  <source>University of Sheffield</source>
  <oversight_info>
    <has_dmc>Yes</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      Chronic thromboembolic pulmonary hypertension (CTEPH) is a severe but treatable disease that&#xD;
      is commonly underdiagnosed. Computed tomography lung subtraction iodine mapping (CT-LSIM) in&#xD;
      addition to standard CT pulmonary angiography (CTPA) may improve the evaluation of suspected&#xD;
      chronic pulmonary embolism and improve the diagnostic pick up rate. The investigators aim to&#xD;
      recruit 100 patients suspected of having CTEPH and perform CT-LSIM scans in addition to the&#xD;
      current gold standard test of nuclear medicine test (lung single photon emission computed&#xD;
      tomography (SPECT) imaging) as a pilot study which will contribute to and inform the&#xD;
      definitive trial. The diagnostic accuracy of CT-LSIM and lung SPECT will be compared. The&#xD;
      primary outcome of the full definitive study is non-inferiority of CT-LSIM versus lung SPECT&#xD;
      imaging.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Chronic thromboembolic pulmonary hypertension (CTEPH) is a treatable, life-threatening&#xD;
      disease that occurs in up to 4% of patients following acute pulmonary embolism (PE)(1). The&#xD;
      disease is characterised by remodelling of the pulmonary arteries due to poor clearance of&#xD;
      clot. Prognosis is very poor without treatment, and pulmonary endarterectomy (PEA) is well&#xD;
      established as the definitive and potentially curative treatment method for CTEPH.&#xD;
&#xD;
      The European Society of Cardiology recommends ventilation/perfusion single photon emission&#xD;
      tomography (V/Q SPECT) as the first line-screening test for patients with CTEPH. The&#xD;
      perfusion image involves injection of 99mTc labelled macroaggregated human albumin, exposing&#xD;
      the patient to ionizing radiation and the study acquisition time is 30-40 minutes.&#xD;
&#xD;
      Evaluation of the pulmonary arterial tree by computed tomography pulmonary angiography (CTPA)&#xD;
      and lung perfusion is required to determine the appropriate treatment strategy in chronic&#xD;
      thromboembolic disease (CTED). Recently, there has been much interest in the application of&#xD;
      lung perfused blood volume images using dual-energy CT (DECT) to assess lung perfusion (2,&#xD;
      3). However, DECT is not widely available in hospitals across the UK and V/Q SPECT remains&#xD;
      the reference standard. The rationale, methodology and design of the IodiNe SubtracTion&#xD;
      mappInG in the diAgnosis of chronic pulmonary ThromboEmbolic disease (INSTIGATE) study are&#xD;
      summarised in this paper.&#xD;
&#xD;
      Rationale of the INSTIGATE study:&#xD;
&#xD;
      Computed tomography lung subtraction iodine mapping (CT-LSIM) and accompanying software is&#xD;
      now available in routine clinical practice (Sure subtractionTM, Toshiba Medical Systems; FDA&#xD;
      report K130960). CT-LSIM images are created using on a non-rigid registration of a low dose&#xD;
      unenhanced thoracic CT to a CTPA, with both examinations performed during the same sitting in&#xD;
      less than 10 minutes total scanning time. Subtraction of the non-contrast CT from the&#xD;
      contrast-enhance CTPA produces the CT-LSIM. CT-LSIM simultaneously provide&#xD;
      high-spatial-resolution images of the pulmonary arterial tree and parenchymal anatomy in&#xD;
      combination with functional examination of lung perfusion.&#xD;
&#xD;
      Magnetic resonance imaging (MRI) is an alternative approach with the advantage of the lack of&#xD;
      ionizing radiation and can produce lung perfusion maps with good diagnostic accuracy for CTED&#xD;
      (5). MRI is relatively limited in comparison to CT in terms of availability and the lack of&#xD;
      ability to provide an out of hours service in some centres. Recently, it has been shown that&#xD;
      Gadolinium is deposited in the basal ganglia, the clinical significance of the retained&#xD;
      gadolinium in the brain, if any, remains unknown (4). Further research is ongoing.&#xD;
&#xD;
      A recent meta-analysis and systematic review, highlights the diagnostic potential of CT in&#xD;
      both screening and for surgical and interventional operability (6).&#xD;
&#xD;
      Replacement of CT for V/Q SPECT in the setting of screening for CTED would lead to a cost&#xD;
      saving per patient. The diagnosed incidence of CTEPH is approximately 700 cases in the UK,&#xD;
      projected to rise to about 1000 in 2025. Estimated pick up rate of perfusion defects in&#xD;
      patients with suspected CTED is 59% at a specialist centre (pick up rates are likely to be&#xD;
      much lower at non-specialist centres). An estimated 1186 patients are screened at specialist&#xD;
      centres, if these patients were screened using CT instead of SPECT, significant cost savings&#xD;
      can be made.&#xD;
&#xD;
      In patients found to have CTED on lung SPECT, CTPA is also required to characterise the&#xD;
      extent of pulmonary arterial clot for surgical planning, and this would be a further cost. By&#xD;
      using CTPA with iodine subtraction mapping for screening and surgical planning.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Not yet recruiting</last_known_status>
  <start_date type="Anticipated">April 1, 2019</start_date>
  <completion_date type="Anticipated">August 30, 2020</completion_date>
  <primary_completion_date type="Anticipated">April 1, 2020</primary_completion_date>
  <study_type>Observational</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <observational_model>Cohort</observational_model>
    <time_perspective>Prospective</time_perspective>
  </study_design_info>
  <primary_outcome>
    <measure>Assessment of the diagnostic performance of CT-LSIM for evaluation of pulmonary perfusion in patients with known or suspected chronic thromboembolic pulmonary hypertension (CTEPH)</measure>
    <time_frame>12 months</time_frame>
    <description>Sensitivity and specificity</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Diagnostic accuracy of CT-LSIM compared with single photon emission computed tomography (SPECT)</measure>
    <time_frame>12 months</time_frame>
    <description>Sensitivity and specificity</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Diagnostic accuracy of CT-LSIM compared with CT pulmonary angiography (CTPA)</measure>
    <time_frame>12 months</time_frame>
    <description>Sensitivity and specificity</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Diagnostic accuracy of experienced and less experienced observers</measure>
    <time_frame>12 months</time_frame>
    <description>Sensitivity and specificity</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Number of alternate diagnoses made on CT-LSIM over lung SPECT imaging</measure>
    <time_frame>12 months</time_frame>
    <description>Chi square</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Radiation dose between CT-LSIM, SPECT and CTPA</measure>
    <time_frame>12 months</time_frame>
    <description>Means</description>
  </secondary_outcome>
  <enrollment type="Anticipated">100</enrollment>
  <condition>Chronic Thromboembolic Pulmonary Hypertension</condition>
  <intervention>
    <intervention_type>Radiation</intervention_type>
    <intervention_name>Computed tomography lung subtraction iodine mapping</intervention_name>
    <description>Subtraction of the non-contrast CT from the contrast-enhance CTPA produces the CT-LSIM</description>
    <other_name>CT-LSIM</other_name>
  </intervention>
  <eligibility>
    <study_pop>
      <textblock>
        Patient suspected to have or diagnosed with chronic thromboembolic disease and require a&#xD;
        SPECT and CTPA&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Patients suspected to have CTED and require a SPECT and CTPA&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Less than 18 years old&#xD;
&#xD;
          -  Unable to provide informed consent&#xD;
&#xD;
          -  Significant renal dysfunction (GFR &lt;30ml/min)&#xD;
&#xD;
          -  History of hypersensitivity to contrast material&#xD;
&#xD;
          -  Pregnancy&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>90 Years</maximum_age>
  </eligibility>
  <overall_official>
    <last_name>David Kiely, MD</last_name>
    <role>Study Director</role>
    <affiliation>Sheffield Teaching Hospitals NHS Foundation Trust</affiliation>
  </overall_official>
  <overall_official>
    <last_name>Yousef Shahin, MD</last_name>
    <role>Study Chair</role>
    <affiliation>University of Sheffield</affiliation>
  </overall_official>
  <overall_official>
    <last_name>Andy J Swift, PhD</last_name>
    <role>Principal Investigator</role>
    <affiliation>University of Sheffield</affiliation>
  </overall_official>
  <overall_official>
    <last_name>Kavitasagary Karunasaagarar</last_name>
    <role>Study Chair</role>
    <affiliation>Sheffield Teaching Hospitals NHS Foundation Trust</affiliation>
  </overall_official>
  <overall_contact>
    <last_name>Andy J Swift, PhD</last_name>
    <phone>0114 2159595</phone>
    <email>a.j.swift@sheffield.ac.uk</email>
  </overall_contact>
  <overall_contact_backup>
    <last_name>Yousef Shahin, MD</last_name>
    <phone>0114 2159595</phone>
    <email>y.shahin@sheffield.ac.uk</email>
  </overall_contact_backup>
  <reference>
    <citation>Pengo V, Lensing AW, Prins MH, Marchiori A, Davidson BL, Tiozzo F, Albanese P, Biasiolo A, Pegoraro C, Iliceto S, Prandoni P; Thromboembolic Pulmonary Hypertension Study Group. Incidence of chronic thromboembolic pulmonary hypertension after pulmonary embolism. N Engl J Med. 2004 May 27;350(22):2257-64. doi: 10.1056/NEJMoa032274.</citation>
    <PMID>15163775</PMID>
  </reference>
  <reference>
    <citation>Hoey ET, Gopalan D, Ganesh V, Agrawal SK, Qureshi N, Tasker AD, Clements L, Screaton NJ. Dual-energy CT pulmonary angiography: a novel technique for assessing acute and chronic pulmonary thromboembolism. Clin Radiol. 2009 Apr;64(4):414-9. doi: 10.1016/j.crad.2008.11.007. Epub 2009 Jan 14. No abstract available. Erratum In: Clin Radiol. 2009 Jul;64(7):748.</citation>
    <PMID>19264187</PMID>
  </reference>
  <reference>
    <citation>Hoey ET, Mirsadraee S, Pepke-Zaba J, Jenkins DP, Gopalan D, Screaton NJ. Dual-energy CT angiography for assessment of regional pulmonary perfusion in patients with chronic thromboembolic pulmonary hypertension: initial experience. AJR Am J Roentgenol. 2011 Mar;196(3):524-32. doi: 10.2214/AJR.10.4842.</citation>
    <PMID>21343493</PMID>
  </reference>
  <reference>
    <citation>Gulani V, Calamante F, Shellock FG, Kanal E, Reeder SB; International Society for Magnetic Resonance in Medicine. Gadolinium deposition in the brain: summary of evidence and recommendations. Lancet Neurol. 2017 Jul;16(7):564-570. doi: 10.1016/S1474-4422(17)30158-8. Epub 2017 Jun 13.</citation>
    <PMID>28653648</PMID>
  </reference>
  <reference>
    <citation>Rajaram S, Swift AJ, Capener D, Telfer A, Davies C, Hill C, Condliffe R, Elliot C, Hurdman J, Kiely DG, Wild JM. Diagnostic accuracy of contrast-enhanced MR angiography and unenhanced proton MR imaging compared with CT pulmonary angiography in chronic thromboembolic pulmonary hypertension. Eur Radiol. 2012 Feb;22(2):310-7. doi: 10.1007/s00330-011-2252-x. Epub 2011 Sep 2.</citation>
    <PMID>21887483</PMID>
  </reference>
  <reference>
    <citation>Dong C, Zhou M, Liu D, Long X, Guo T, Kong X. Diagnostic accuracy of computed tomography for chronic thromboembolic pulmonary hypertension: a systematic review and meta-analysis. PLoS One. 2015 Apr 29;10(4):e0126985. doi: 10.1371/journal.pone.0126985. eCollection 2015.</citation>
    <PMID>25923810</PMID>
  </reference>
  <verification_date>February 2019</verification_date>
  <study_first_submitted>January 15, 2019</study_first_submitted>
  <study_first_submitted_qc>January 15, 2019</study_first_submitted_qc>
  <study_first_posted type="Actual">January 16, 2019</study_first_posted>
  <last_update_submitted>February 8, 2019</last_update_submitted>
  <last_update_submitted_qc>February 8, 2019</last_update_submitted_qc>
  <last_update_posted type="Actual">February 12, 2019</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>University of Sheffield</investigator_affiliation>
    <investigator_full_name>Andy J Swift</investigator_full_name>
    <investigator_title>Principal Investigator and Wellcome Trust Clinical Fellow in Radiology and Consultant Cardiothoracic Radiologist</investigator_title>
  </responsible_party>
  <keyword>INSITIGATE</keyword>
  <keyword>Pulmonary Hypertension</keyword>
  <keyword>Pulmonary embolism</keyword>
  <keyword>Chronic Thromboembolism</keyword>
  <keyword>Iodine Subtraction</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Hypertension, Pulmonary</mesh_term>
    <mesh_term>Hypertension</mesh_term>
    <mesh_term>Thromboembolism</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>No</sharing_ipd>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT03806907
org study id: STH20623
nct id: NCT03806907
lead sponsor: 
collaborator: 
has dmc: Yes
is fda regulated drug: No
is fda regulated device: No
Chronic thromboembolic pulmonary hypertension (CTEPH) is a severe but treatable disease that
      is commonly underdiagnosed. Computed tomography lung subtraction iodine mapping (CT-LSIM) in
      addition to standard CT pulmonary angiography (CTPA) may improve the evaluation of suspected
      chronic pulmonary embolism and improve the diagnostic pick up rate. The investigators aim to
      recruit 100 patients suspected of having CTEPH and perform CT-LSIM scans in addition to the
      current gold standard test of nuclear medicine test (lung single photon emission computed
      tomography (SPECT) imaging) as a pilot study which will contribute to and inform the
      definitive trial. The diagnostic accuracy of CT-LSIM and lung SPECT will be compared. The
      primary outcome of the full definitive study is non-inferiority of CT-LSIM versus lung SPECT
      imaging.
Chronic thromboembolic pulmonary hypertension (CTEPH) is a treatable, life-threatening
      disease that occurs in up to 4% of patients following acute pulmonary embolism (PE)(1). The
      disease is characterised by remodelling of the pulmonary arteries due to poor clearance of
      clot. Prognosis is very poor without treatment, and pulmonary endarterectomy (PEA) is well
      established as the definitive and potentially curative treatment method for CTEPH.

      The European Society of Cardiology recommends ventilation/perfusion single photon emission
      tomography (V/Q SPECT) as the first line-screening test for patients with CTEPH. The
      perfusion image involves injection of 99mTc labelled macroaggregated human albumin, exposing
      the patient to ionizing radiation and the study acquisition time is 30-40 minutes.

      Evaluation of the pulmonary arterial tree by computed tomography pulmonary angiography (CTPA)
      and lung perfusion is required to determine the appropriate treatment strategy in chronic
      thromboembolic disease (CTED). Recently, there has been much interest in the application of
      lung perfused blood volume images using dual-energy CT (DECT) to assess lung perfusion (2,
      3). However, DECT is not widely available in hospitals across the UK and V/Q SPECT remains
      the reference standard. The rationale, methodology and design of the IodiNe SubtracTion
      mappInG in the diAgnosis of chronic pulmonary ThromboEmbolic disease (INSTIGATE) study are
      summarised in this paper.

      Rationale of the INSTIGATE study:

      Computed tomography lung subtraction iodine mapping (CT-LSIM) and accompanying software is
      now available in routine clinical practice (Sure subtractionTM, Toshiba Medical Systems; FDA
      report K130960). CT-LSIM images are created using on a non-rigid registration of a low dose
      unenhanced thoracic CT to a CTPA, with both examinations performed during the same sitting in
      less than 10 minutes total scanning time. Subtraction of the non-contrast CT from the
      contrast-enhance CTPA produces the CT-LSIM. CT-LSIM simultaneously provide
      high-spatial-resolution images of the pulmonary arterial tree and parenchymal anatomy in
      combination with functional examination of lung perfusion.

      Magnetic resonance imaging (MRI) is an alternative approach with the advantage of the lack of
      ionizing radiation and can produce lung perfusion maps with good diagnostic accuracy for CTED
      (5). MRI is relatively limited in comparison to CT in terms of availability and the lack of
      ability to provide an out of hours service in some centres. Recently, it has been shown that
      Gadolinium is deposited in the basal ganglia, the clinical significance of the retained
      gadolinium in the brain, if any, remains unknown (4). Further research is ongoing.

      A recent meta-analysis and systematic review, highlights the diagnostic potential of CT in
      both screening and for surgical and interventional operability (6).

      Replacement of CT for V/Q SPECT in the setting of screening for CTED would lead to a cost
      saving per patient. The diagnosed incidence of CTEPH is approximately 700 cases in the UK,
      projected to rise to about 1000 in 2025. Estimated pick up rate of perfusion defects in
      patients with suspected CTED is 59% at a specialist centre (pick up rates are likely to be
      much lower at non-specialist centres). An estimated 1186 patients are screened at specialist
      centres, if these patients were screened using CT instead of SPECT, significant cost savings
      can be made.

      In patients found to have CTED on lung SPECT, CTPA is also required to characterise the
      extent of pulmonary arterial clot for surgical planning, and this would be a further cost. By
      using CTPA with iodine subtraction mapping for screening and surgical planning.
observational model: Cohort
time perspective: Prospective
measure: Assessment of the diagnostic performance of CT-LSIM for evaluation of pulmonary perfusion in patients with known or suspected chronic thromboembolic pulmonary hypertension (CTEPH)
time frame: 12 months
description: Sensitivity and specificity
measure: Diagnostic accuracy of CT-LSIM compared with single photon emission computed tomography (SPECT)
time frame: 12 months
description: Sensitivity and specificity
measure: Diagnostic accuracy of CT-LSIM compared with CT pulmonary angiography (CTPA)
time frame: 12 months
description: Sensitivity and specificity
measure: Diagnostic accuracy of experienced and less experienced observers
time frame: 12 months
description: Sensitivity and specificity
measure: Number of alternate diagnoses made on CT-LSIM over lung SPECT imaging
time frame: 12 months
description: Chi square
measure: Radiation dose between CT-LSIM, SPECT and CTPA
time frame: 12 months
description: Means
intervention type: Radiation
intervention name: Computed tomography lung subtraction iodine mapping
description: Subtraction of the non-contrast CT from the contrast-enhance CTPA produces the CT-LSIM
other name: CT-LSIM
study pop: 
sampling method: Probability Sample
criteria: 
gender: All
minimum age: 18 Years
maximum age: 90 Years
last name: David Kiely, MD
role: Study Director
affiliation: Sheffield Teaching Hospitals NHS Foundation Trust
last name: Yousef Shahin, MD
role: Study Chair
affiliation: University of Sheffield
last name: Andy J Swift, PhD
role: Principal Investigator
affiliation: University of Sheffield
last name: Kavitasagary Karunasaagarar
role: Study Chair
affiliation: Sheffield Teaching Hospitals NHS Foundation Trust
last name: Andy J Swift, PhD
phone: 0114 2159595
email: a.j.swift@sheffield.ac.uk
last name: Yousef Shahin, MD
phone: 0114 2159595
email: y.shahin@sheffield.ac.uk
citation: Pengo V, Lensing AW, Prins MH, Marchiori A, Davidson BL, Tiozzo F, Albanese P, Biasiolo A, Pegoraro C, Iliceto S, Prandoni P; Thromboembolic Pulmonary Hypertension Study Group. Incidence of chronic thromboembolic pulmonary hypertension after pulmonary embolism. N Engl J Med. 2004 May 27;350(22):2257-64. doi: 10.1056/NEJMoa032274.
PMID: 15163775
citation: Hoey ET, Gopalan D, Ganesh V, Agrawal SK, Qureshi N, Tasker AD, Clements L, Screaton NJ. Dual-energy CT pulmonary angiography: a novel technique for assessing acute and chronic pulmonary thromboembolism. Clin Radiol. 2009 Apr;64(4):414-9. doi: 10.1016/j.crad.2008.11.007. Epub 2009 Jan 14. No abstract available. Erratum In: Clin Radiol. 2009 Jul;64(7):748.
PMID: 19264187
citation: Hoey ET, Mirsadraee S, Pepke-Zaba J, Jenkins DP, Gopalan D, Screaton NJ. Dual-energy CT angiography for assessment of regional pulmonary perfusion in patients with chronic thromboembolic pulmonary hypertension: initial experience. AJR Am J Roentgenol. 2011 Mar;196(3):524-32. doi: 10.2214/AJR.10.4842.
PMID: 21343493
citation: Gulani V, Calamante F, Shellock FG, Kanal E, Reeder SB; International Society for Magnetic Resonance in Medicine. Gadolinium deposition in the brain: summary of evidence and recommendations. Lancet Neurol. 2017 Jul;16(7):564-570. doi: 10.1016/S1474-4422(17)30158-8. Epub 2017 Jun 13.
PMID: 28653648
citation: Rajaram S, Swift AJ, Capener D, Telfer A, Davies C, Hill C, Condliffe R, Elliot C, Hurdman J, Kiely DG, Wild JM. Diagnostic accuracy of contrast-enhanced MR angiography and unenhanced proton MR imaging compared with CT pulmonary angiography in chronic thromboembolic pulmonary hypertension. Eur Radiol. 2012 Feb;22(2):310-7. doi: 10.1007/s00330-011-2252-x. Epub 2011 Sep 2.
PMID: 21887483
citation: Dong C, Zhou M, Liu D, Long X, Guo T, Kong X. Diagnostic accuracy of computed tomography for chronic thromboembolic pulmonary hypertension: a systematic review and meta-analysis. PLoS One. 2015 Apr 29;10(4):e0126985. doi: 10.1371/journal.pone.0126985. eCollection 2015.
PMID: 25923810
responsible party type: Principal Investigator
investigator affiliation: University of Sheffield
investigator full name: Andy J Swift
investigator title: Principal Investigator and Wellcome Trust Clinical Fellow in Radiology and Consultant Cardiothoracic Radiologist
mesh term: Hypertension, Pulmonary
mesh term: Hypertension
mesh term: Thromboembolism
sharing ipd: No