NCT03637231

Brief Summary

Radiation exposure to patients from CT for CAC scoring has steadily decreased in recent years. This is mainly achieved through lowering tube currents alongside with the introduction of iterative reconstruction algorithms which allow compensating for increased image noise. However, the greatest radiation dose reduction can be obtained by reducing peak tube voltage. Yet lowering peak tube voltage remains challenging because tissue attenuation is closely related to photon energy, thus rendering the established thresholds for calculating CAC scores (i.e. Agatston scores) incomparable if peak tube voltages other than the standard 120 kilovolt peak (kVp) are applied. The investigators have developed novel tube-adapted thresholds for CAC scoring by CT at 80 kVp and 70-kVp tube voltage and have shown that these novel thresholds are valid, yielding results closely comparable to the standard 120-kVp protocol. The present study aims to optimize application of such low-dose scans in a general population through assessment of the impact of physiological patient parameters on image parameters such as image noise which per se may impact the accuracy and feasibility of ultra-low-dose CAC scoring with reduced tube voltage. Furthermore, the prognostic performance of such low-dose CAC scoring will be elucidated.

Trial Health

57
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
301

participants targeted

Target at P50-P75 for not_applicable coronary-artery-disease

Timeline
Completed

Started Jul 2018

Typical duration for not_applicable coronary-artery-disease

Geographic Reach
1 country

1 active site

Status
terminated

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

July 5, 2018

Completed
21 days until next milestone

First Submitted

Initial submission to the registry

July 26, 2018

Completed
22 days until next milestone

First Posted

Study publicly available on registry

August 17, 2018

Completed
3.2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

October 25, 2021

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

October 25, 2021

Completed
Last Updated

November 14, 2022

Status Verified

November 1, 2022

Enrollment Period

3.3 years

First QC Date

July 26, 2018

Last Update Submit

November 7, 2022

Conditions

Outcome Measures

Primary Outcomes (1)

  • Impact of BMI on CAC scores derived from low-dose versus standard-dose CT

    Assessment of deviation of CAC scores derived from low-dose CT versus standard-dose CT (i.e. standard of reference) by calculating bias and Bland-Altmann limits of agreement as well as intraclass correlation in different subgroups of patients, stratified by body mass index.

    2 years

Secondary Outcomes (1)

  • Prognostic value of CAC scores derived from CT scans with varying tube voltages

    2 years

Study Arms (1)

Standard and ultra-low-dose CAC scoring

OTHER
Diagnostic Test: Ultra low-dose CTAC

Interventions

Ultra low-dose CTACDIAGNOSTIC_TEST

All patients undergo two non-contrast enhanced CT scans with standard dose (i.e. 120 kVp), one with 80 kVp and one with 70 kVp.

Standard and ultra-low-dose CAC scoring

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Patients referred for a non-contrast enhanced CT scan for CAC scoring
  • Male and Female subjects ≥18 years of age,
  • Written informed consent

You may not qualify if:

  • Pregnancy or breast-feeding
  • History of coronary artery stenting, coronary artery bypass grafting, of implantation of cardiac devices (e.g. valve prosthesis, pacemaker, implantable cardioverter defibrillator etc.)
  • Enrolment of the investigator, his/her family members, employees and other dependent persons

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Department of Nuclear Medicine, University Hospital Zurich

Zurich, 8091, Switzerland

Location

Related Publications (3)

  • Grani C, Vontobel J, Benz DC, Bacanovic S, Giannopoulos AA, Messerli M, Grossmann M, Gebhard C, Pazhenkottil AP, Gaemperli O, Kaufmann PA, Buechel RR. Ultra-low-dose coronary artery calcium scoring using novel scoring thresholds for low tube voltage protocols-a pilot study. Eur Heart J Cardiovasc Imaging. 2018 Dec 1;19(12):1362-1371. doi: 10.1093/ehjci/jey019.

    PMID: 29432592BACKGROUND
  • Bechtiger FA, Grossmann M, Bakula A, Patriki D, von Felten E, Fuchs TA, Gebhard C, Pazhenkottil AP, Kaufmann PA, Buechel RR. Risk stratification using coronary artery calcium scoring based on low tube voltage computed tomography. Int J Cardiovasc Imaging. 2022 Oct;38(10):2227-2234. doi: 10.1007/s10554-022-02615-x. Epub 2022 Apr 23.

  • Sartoretti T, Gennari AG, Sartoretti E, Skawran S, Maurer A, Buechel RR, Messerli M. Fully automated deep learning powered calcium scoring in patients undergoing myocardial perfusion imaging. J Nucl Cardiol. 2023 Feb;30(1):313-320. doi: 10.1007/s12350-022-02940-7. Epub 2022 Mar 17.

MeSH Terms

Conditions

Coronary Artery Disease

Condition Hierarchy (Ancestors)

Coronary DiseaseMyocardial IschemiaHeart DiseasesCardiovascular DiseasesArteriosclerosisArterial Occlusive DiseasesVascular Diseases

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
DIAGNOSTIC
Intervention Model
SEQUENTIAL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

July 26, 2018

First Posted

August 17, 2018

Study Start

July 5, 2018

Primary Completion

October 25, 2021

Study Completion

October 25, 2021

Last Updated

November 14, 2022

Record last verified: 2022-11

Data Sharing

IPD Sharing
Will not share

Locations