<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/NCT02996903</url>
  </required_header>
  <id_info>
    <org_study_id>MUC I002-16</org_study_id>
    <nct_id>NCT02996903</nct_id>
  </id_info>
  <brief_title>Prospective Multicenter Registry On RadiaTion Dose Estimates Of Cardiac CT AngIOgraphy IN Daily Practice in 2017</brief_title>
  <acronym>PROTECTION-VI</acronym>
  <official_title>Prospective Multicenter Registry On RadiaTion Dose Estimates Of Cardiac CT AngIOgraphy IN Daily Practice in 2017</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>LMU Klinikum</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>LMU Klinikum</source>
  <oversight_info>
    <has_dmc>Yes</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      The &quot;Prospective Multicenter Registry On RadiaTion Dose Estimates Of Cardiac CT AngIOgraphy&#xD;
      IN Daily Practice in 2017&quot; (PROTECTION-VI) study is a prospective registry and&#xD;
      investigator-initiated initiative without third-party funding, which will collect and analyze&#xD;
      the radiation dose exposure of Cardiac Computed Tomography Angiographic (CCTA) studies in&#xD;
      current daily practice worldwide. Particularly, the study will assess the use of strategies&#xD;
      for dose reduction during CCTA.&#xD;
&#xD;
      A decade ago, the multicentre observational PROTECTION-I study has revealed that the&#xD;
      dose-length-product of CCTA ranges between 568 - 1259 mGy x cm with a median of 885 mGy x cm.&#xD;
      This corresponds to an estimated effective dose of approximately 12 mSv. Since then a variety&#xD;
      of techniques have been developed and enhanced in order to reduce radiation exposure during&#xD;
      CCTA. Recent studies demonstrated feasibility of dramatically reduced effective radiation&#xD;
      doses during CCTA (0,1 - 0,3 mSv). This has been executed in small cohorts of patients at&#xD;
      scientific expert centers. However, it remains unclear, if such low-level radiation dose&#xD;
      exposure may be achieved in clinical routine and if diagnostic image quality is maintained.&#xD;
      In order to analyze the magnitude of radiation dose exposure of CCTA in today's clinical&#xD;
      practice and the current use of dose-saving techniques, we designed the PROTECTION-VI study.&#xD;
      Eventually, this study may contribute to further improving radiation dose exposure for&#xD;
      patients undergoing CCTA.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Cardiac CT angiography (CCTA) has emerged to a powerful and commonly used diagnostic tool for&#xD;
      the evaluation of coronary artery disease. Advantages of CCTA are its non-invasive approach,&#xD;
      widespread availability and high negative predictive value to rule out coronary artery&#xD;
      disease. However, radiation exposure during CCTA needs to be considered, due to the potential&#xD;
      risk of malignancy induction.&#xD;
&#xD;
      A decade ago, the multicentre observational PROTECTION I study has revealed that the&#xD;
      dose-length-product of CCTA ranges between 568-1259 mGy x cm with a median of 885 mGy x cm.&#xD;
      This corresponds to an estimated effective dose of approximately 12 mSv. Furthermore,&#xD;
      PROTECTION I demonstrated an up to 7-fold variation of radiation dose between different study&#xD;
      sites implicating the large potential for dose reduction. Finally, significant differences&#xD;
      have been detected in the radiation exposures between CT systems from different vendors and&#xD;
      application of dose-saving algorithms, implying that approaches for dose reduction with&#xD;
      respect to hardware and software have also been of relevance in 2007.&#xD;
&#xD;
      Since then a variety of techniques have been developed and enhanced in order to reduce&#xD;
      radiation exposure during CCTA. Earlier, ECG-controlled tube current modulation has been&#xD;
      accepted to reduce radiation dose and was therefore used in ECG-gated retrospective cardiac&#xD;
      spiral scanning.&#xD;
&#xD;
      Another dose-saving technique is the reduction of tube potential from conventionally 120 kVp&#xD;
      to 100 kVp in non-obese patients. In the PROTECTION II trial we demonstrated that diagnostic&#xD;
      image quality is being maintained with a reduction of tube potential to 100 kVp while&#xD;
      radiation exposure was significantly reduced by 31%.&#xD;
&#xD;
      Development of prospective ECG-gated axial (sequential) scanning allowed further dose&#xD;
      reduction, due to administration of radiation only at the end of diastole. In the PROTECTION&#xD;
      III trial we could demonstrate that diagnostic image quality is being maintained with&#xD;
      prospective ECG-gated axial scanning in patients with stable and low heart rates while&#xD;
      radiation exposure was reduced by 69% when compared to conventional spiral scanning with&#xD;
      retrospective ECG gating. Using prospectively ECG-triggered high-pitch spiral CCTA with image&#xD;
      acquisition during only one cardiac cycle, additional dosage may be saved when used in&#xD;
      selected patients with low and stable heart rates. However, a scan strategy with an attempt&#xD;
      of high-pitch scanning first is vulnerable to motion artefacts and bears the risk of repeated&#xD;
      scanning.&#xD;
&#xD;
      In the PROTECTION IV trial we compared a scan strategy of high-pitch helical scanning first&#xD;
      with a conventional scan first strategy. We could demonstrate maintenance of image quality&#xD;
      using the strategy of high-pitch helical scanning first, while radiation exposure was reduced&#xD;
      by 57 %, when compared to the conventional scan first strategy.&#xD;
&#xD;
      The introduction of iterative image reconstruction technique with advanced raw data&#xD;
      processing let to improvement of image quality compared to traditional filtered back&#xD;
      projection. This allowed additional dose saving during image acquisition. In the PROTECTION V&#xD;
      trial we demonstrated the feasibility of combining iterative image reconstruction techniques&#xD;
      with a reduction of tube currents by 30% leading to maintenance of diagnostic image quality&#xD;
      while saving radiation dose linearly to tube current.&#xD;
&#xD;
      In summary, the four randomized clinical trials PROTECTION II-V demonstrated that different&#xD;
      techniques for reducing radiation exposure during CCTA can be applied in clinical practice&#xD;
      without compromising diagnostic image quality. The studies show that the different approaches&#xD;
      can also be applied in combination and that these approaches can be used with different CT&#xD;
      platforms from different CT vendors.&#xD;
&#xD;
      Recent studies demonstrated that the effective radiation dose for one CCTA scan may be&#xD;
      reduced to 0,3 mSv15 or even below 0,1 mSv in a small amount of carefully selected patients.&#xD;
      However, it remains unclear if such dramatically low dosages are being achieved and if&#xD;
      diagnostic image quality is being maintained in clinical routine. In order to analyze the&#xD;
      magnitude of radiation dose exposure during CCTA in today's clinical practice, we designed&#xD;
      the international and multicentric PROTECTION VI study. We will assess the variation of&#xD;
      radiation dose with respect to vendors, CT systems and study sites. Furthermore, we will&#xD;
      evaluate the usage of dose saving strategies including the above-mentioned in daily practice&#xD;
      and analyze their effect on diagnostic image quality. On the basis of the collected data, we&#xD;
      will evaluate the potential use of additional dose savings for each site individually.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date type="Actual">March 1, 2017</start_date>
  <completion_date type="Actual">December 31, 2017</completion_date>
  <primary_completion_date type="Actual">October 31, 2017</primary_completion_date>
  <study_type>Observational [Patient Registry]</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <observational_model>Other</observational_model>
    <time_perspective>Prospective</time_perspective>
  </study_design_info>
  <target_duration>1 Day</target_duration>
  <primary_outcome>
    <measure>Radiation dose estimates of cardiac CT angiographies in daily practice</measure>
    <time_frame>Baseline</time_frame>
    <description>Assessment after CT scan by radiologist or technical assistant, documented on questionnaire.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Use of dose-saving strategies</measure>
    <time_frame>Baseline</time_frame>
    <description>Use of Low tube potential imaging, Low tube current imaging, Automated Exposure Control, ECG-controlled tube current modulation (dose pulsing), Iterative image reconstruction techniques and Scan protocols (Prospective ECG-triggered axial scanning technique, Prospective ECG-triggered high-pitch spiral acquisition) will be assessed in the Core Lab according to information given by the CT-examiner on a questionnaire.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Assessment of CCTA image quality in relation to radiation dose</measure>
    <time_frame>Baseline</time_frame>
    <description>Assessment after CT scan by CT-examiner on questionnaire (qualitative) or in the Core Lab (quantitative).&#xD;
Quantitative Assessment includes Signal intensity, Image noise, Contrast-to-noise ratio, Signal-to-noise ratio. Qualitative assessment of each coronary artery is performed using a 3-point grading scale including excellent, intermediate or non-diagnostic as documented on a provided questionnaire.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Sufficient result of the first CCTA scan or need for repeated scans</measure>
    <time_frame>Baseline</time_frame>
    <description>According to information given by the CT-examiner on a questionnaire.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Cardiac CT scan length and relationship between scan and heart length</measure>
    <time_frame>Baseline</time_frame>
    <description>Assessment in Core Lab after analysis of CT scans.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Comparison of dose estimates between different continents, CT vendors and CT systems</measure>
    <time_frame>Baseline</time_frame>
    <description>Analysis done in the Core Lab according to information given by the CT-examiner on a questionnaire.</description>
  </secondary_outcome>
  <enrollment type="Actual">4502</enrollment>
  <condition>Coronary Artery Disease</condition>
  <condition>Cardiac Disease</condition>
  <condition>Malignancy, Second</condition>
  <eligibility>
    <study_pop>
      <textblock>
        Patients undergoing Cardiac Computed Tomography Angiography (CCTA) in clinical routine.&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Patients with a clinical indication for CCTA in order to evaluate the coronary&#xD;
             arteries or other cardiac structures&#xD;
&#xD;
          -  Patients age &gt; 18 years&#xD;
&#xD;
          -  Signed informed consent (if required by local IRB)&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Known allergy to contrast agent&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <location>
    <facility>
      <name>National Heart, Lung, and Blood Institute</name>
      <address>
        <city>Bethesda</city>
        <state>Maryland</state>
        <zip>20892-1061</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location>
    <facility>
      <name>University of British Columbia, Department of Medical Imaging</name>
      <address>
        <city>Vancouver</city>
        <state>British Columbia</state>
        <country>Canada</country>
      </address>
    </facility>
  </location>
  <location>
    <facility>
      <name>Ludwig-Maximilians-Universitaet Muenchen, Medizinische Klinik I</name>
      <address>
        <city>Munich</city>
        <state>Bavaria</state>
        <zip>808303</zip>
        <country>Germany</country>
      </address>
    </facility>
  </location>
  <location>
    <facility>
      <name>Technion Israel Institute of Technology, The Ruth and Bruce Rappaport Faculty of Medicine</name>
      <address>
        <city>Haifa</city>
        <country>Israel</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>Canada</country>
    <country>Germany</country>
    <country>Israel</country>
    <country>United States</country>
  </location_countries>
  <verification_date>May 2018</verification_date>
  <study_first_submitted>December 13, 2016</study_first_submitted>
  <study_first_submitted_qc>December 14, 2016</study_first_submitted_qc>
  <study_first_posted type="Estimate">December 19, 2016</study_first_posted>
  <last_update_submitted>May 12, 2018</last_update_submitted>
  <last_update_submitted_qc>May 12, 2018</last_update_submitted_qc>
  <last_update_posted type="Actual">May 15, 2018</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>LMU Klinikum</investigator_affiliation>
    <investigator_full_name>Thomas Stocker</investigator_full_name>
    <investigator_title>Co-Principal Investigator</investigator_title>
  </responsible_party>
  <keyword>Cardiac Computed Tomography (CT) Angiography (CCTA)</keyword>
  <keyword>coronary artery disease</keyword>
  <keyword>malignancy induction</keyword>
  <keyword>radiation dose</keyword>
  <keyword>dose saving techniques</keyword>
  <keyword>effective dose</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Neoplasms</mesh_term>
    <mesh_term>Neoplasms, Second Primary</mesh_term>
    <mesh_term>Coronary Artery Disease</mesh_term>
    <mesh_term>Myocardial Ischemia</mesh_term>
    <mesh_term>Coronary Disease</mesh_term>
    <mesh_term>Heart Diseases</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/NCT02996903
org study id: MUC I002-16
nct id: NCT02996903
lead sponsor: 
has dmc: Yes
The "Prospective Multicenter Registry On RadiaTion Dose Estimates Of Cardiac CT AngIOgraphy
      IN Daily Practice in 2017" (PROTECTION-VI) study is a prospective registry and
      investigator-initiated initiative without third-party funding, which will collect and analyze
      the radiation dose exposure of Cardiac Computed Tomography Angiographic (CCTA) studies in
      current daily practice worldwide. Particularly, the study will assess the use of strategies
      for dose reduction during CCTA.

      A decade ago, the multicentre observational PROTECTION-I study has revealed that the
      dose-length-product of CCTA ranges between 568 - 1259 mGy x cm with a median of 885 mGy x cm.
      This corresponds to an estimated effective dose of approximately 12 mSv. Since then a variety
      of techniques have been developed and enhanced in order to reduce radiation exposure during
      CCTA. Recent studies demonstrated feasibility of dramatically reduced effective radiation
      doses during CCTA (0,1 - 0,3 mSv). This has been executed in small cohorts of patients at
      scientific expert centers. However, it remains unclear, if such low-level radiation dose
      exposure may be achieved in clinical routine and if diagnostic image quality is maintained.
      In order to analyze the magnitude of radiation dose exposure of CCTA in today's clinical
      practice and the current use of dose-saving techniques, we designed the PROTECTION-VI study.
      Eventually, this study may contribute to further improving radiation dose exposure for
      patients undergoing CCTA.
Cardiac CT angiography (CCTA) has emerged to a powerful and commonly used diagnostic tool for
      the evaluation of coronary artery disease. Advantages of CCTA are its non-invasive approach,
      widespread availability and high negative predictive value to rule out coronary artery
      disease. However, radiation exposure during CCTA needs to be considered, due to the potential
      risk of malignancy induction.

      A decade ago, the multicentre observational PROTECTION I study has revealed that the
      dose-length-product of CCTA ranges between 568-1259 mGy x cm with a median of 885 mGy x cm.
      This corresponds to an estimated effective dose of approximately 12 mSv. Furthermore,
      PROTECTION I demonstrated an up to 7-fold variation of radiation dose between different study
      sites implicating the large potential for dose reduction. Finally, significant differences
      have been detected in the radiation exposures between CT systems from different vendors and
      application of dose-saving algorithms, implying that approaches for dose reduction with
      respect to hardware and software have also been of relevance in 2007.

      Since then a variety of techniques have been developed and enhanced in order to reduce
      radiation exposure during CCTA. Earlier, ECG-controlled tube current modulation has been
      accepted to reduce radiation dose and was therefore used in ECG-gated retrospective cardiac
      spiral scanning.

      Another dose-saving technique is the reduction of tube potential from conventionally 120 kVp
      to 100 kVp in non-obese patients. In the PROTECTION II trial we demonstrated that diagnostic
      image quality is being maintained with a reduction of tube potential to 100 kVp while
      radiation exposure was significantly reduced by 31%.

      Development of prospective ECG-gated axial (sequential) scanning allowed further dose
      reduction, due to administration of radiation only at the end of diastole. In the PROTECTION
      III trial we could demonstrate that diagnostic image quality is being maintained with
      prospective ECG-gated axial scanning in patients with stable and low heart rates while
      radiation exposure was reduced by 69% when compared to conventional spiral scanning with
      retrospective ECG gating. Using prospectively ECG-triggered high-pitch spiral CCTA with image
      acquisition during only one cardiac cycle, additional dosage may be saved when used in
      selected patients with low and stable heart rates. However, a scan strategy with an attempt
      of high-pitch scanning first is vulnerable to motion artefacts and bears the risk of repeated
      scanning.

      In the PROTECTION IV trial we compared a scan strategy of high-pitch helical scanning first
      with a conventional scan first strategy. We could demonstrate maintenance of image quality
      using the strategy of high-pitch helical scanning first, while radiation exposure was reduced
      by 57 %, when compared to the conventional scan first strategy.

      The introduction of iterative image reconstruction technique with advanced raw data
      processing let to improvement of image quality compared to traditional filtered back
      projection. This allowed additional dose saving during image acquisition. In the PROTECTION V
      trial we demonstrated the feasibility of combining iterative image reconstruction techniques
      with a reduction of tube currents by 30% leading to maintenance of diagnostic image quality
      while saving radiation dose linearly to tube current.

      In summary, the four randomized clinical trials PROTECTION II-V demonstrated that different
      techniques for reducing radiation exposure during CCTA can be applied in clinical practice
      without compromising diagnostic image quality. The studies show that the different approaches
      can also be applied in combination and that these approaches can be used with different CT
      platforms from different CT vendors.

      Recent studies demonstrated that the effective radiation dose for one CCTA scan may be
      reduced to 0,3 mSv15 or even below 0,1 mSv in a small amount of carefully selected patients.
      However, it remains unclear if such dramatically low dosages are being achieved and if
      diagnostic image quality is being maintained in clinical routine. In order to analyze the
      magnitude of radiation dose exposure during CCTA in today's clinical practice, we designed
      the international and multicentric PROTECTION VI study. We will assess the variation of
      radiation dose with respect to vendors, CT systems and study sites. Furthermore, we will
      evaluate the usage of dose saving strategies including the above-mentioned in daily practice
      and analyze their effect on diagnostic image quality. On the basis of the collected data, we
      will evaluate the potential use of additional dose savings for each site individually.
observational model: Other
time perspective: Prospective
measure: Radiation dose estimates of cardiac CT angiographies in daily practice
time frame: Baseline
description: Assessment after CT scan by radiologist or technical assistant, documented on questionnaire.
measure: Use of dose-saving strategies
time frame: Baseline
description: Use of Low tube potential imaging, Low tube current imaging, Automated Exposure Control, ECG-controlled tube current modulation (dose pulsing), Iterative image reconstruction techniques and Scan protocols (Prospective ECG-triggered axial scanning technique, Prospective ECG-triggered high-pitch spiral acquisition) will be assessed in the Core Lab according to information given by the CT-examiner on a questionnaire.
measure: Assessment of CCTA image quality in relation to radiation dose
time frame: Baseline
description: Assessment after CT scan by CT-examiner on questionnaire (qualitative) or in the Core Lab (quantitative).
Quantitative Assessment includes Signal intensity, Image noise, Contrast-to-noise ratio, Signal-to-noise ratio. Qualitative assessment of each coronary artery is performed using a 3-point grading scale including excellent, intermediate or non-diagnostic as documented on a provided questionnaire.
measure: Sufficient result of the first CCTA scan or need for repeated scans
time frame: Baseline
description: According to information given by the CT-examiner on a questionnaire.
measure: Cardiac CT scan length and relationship between scan and heart length
time frame: Baseline
description: Assessment in Core Lab after analysis of CT scans.
measure: Comparison of dose estimates between different continents, CT vendors and CT systems
time frame: Baseline
description: Analysis done in the Core Lab according to information given by the CT-examiner on a questionnaire.
study pop: 
sampling method: Probability Sample
criteria: 
gender: All
minimum age: 18 Years
maximum age: N/A
healthy volunteers: No
facility: 
facility: 
facility: 
facility: 
country: Canada
country: Germany
country: Israel
country: United States
responsible party type: Principal Investigator
investigator affiliation: LMU Klinikum
investigator full name: Thomas Stocker
investigator title: Co-Principal Investigator
mesh term: Neoplasms
mesh term: Neoplasms, Second Primary
mesh term: Coronary Artery Disease
mesh term: Myocardial Ischemia
mesh term: Coronary Disease
mesh term: Heart Diseases
sharing ipd: No