Clinical trial NCT02011061: Validation of Coronary Calcium Subtraction to Improve Diagnostic Accuracy of Coronary CT Angiography
Official title: Prospective International Study of Coronary Substraction Using 320 Row-detector CT
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Coronary Artery Disease
Keywords: Multidetector Computed Tomography
Coronary Stenosis
Coronary Artery Disease
Angina Pectoris
Lead sponsor: Rigshospitalet, Denmark
Sponsor class: OTHER
Collaborators: name: National Heart, Lung, and Blood Institute (NHLBI)
First posted: 2013-12-13
Enrollment: 182
Sex: ALL
Minimum age (years): 55
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Patients (N=200) referred for in hospital invasive coronary evaluation

Brief summary: Coronary calcium hampers accurate evaluation of the coronary arteries with coronary computed tomography angiography (CCTA). A novel approach to potentially overcome this limitation is coronary calcium subtraction.

The primary hypothesis of the study is:

- Coronary calcium subtraction CCTA will improve diagnostic accuracy as compared to conventional CCTA on a per-patient basis

Detailed description: CCTA is a very important clinical method for the clinical evaluation of patients with chest pain of potential cardiac ischemic origin. However Coronary calcification and/or previously implanted coronary stents may limit the diagnostic accuracy of CCTA. A novel approach - coronary calcium subtraction - has been developed to potentially overcome this limitation.

* Study Objective: To assess diagnostic accuracy using coronary calcium subtraction coronary CT angiography (CCTA) as compared to conventional CCTA.
* Material and Methods: A total of 200 patients with suspected or known coronary artery disease (CAD) who have been referred for invasive coronary angiography (ICA) will prior to ICA undergo additional research CCTA with the newly developed coronary calcium subtraction protocol. Based on the coronary calcium scan (CS), coronary calcium score will be calculated according to the Agatston score. Conventional contrast enhanced CCTA studies will be analyzed for image quality and the presence and extent of coronary stenosis. Using a dedicated algorithm, subtraction will be performed on all datasets to obtain CCTA subtraction images. Subtracted images will be analyzed similar to the conventional CCTA images. ICA will serve as the gold standard. Image quality will be compared between conventional and subtracted CCTA. In addition, diagnostic accuracy in the evaluation of coronary stenosis as determined on ICA will be compared. Finally, factors influencing the performance of coronary calcium subtraction will be evaluated.

Eligibility criteria: Inclusion Criteria:

* Age \> 55 Years
* Scheduled for invasive coronary angiography
* Logistically possible to perform CCTA before invasive evaluation

Exclusion Criteria:

* Known Iodine-contrast allergy
* Estimated GFR below 50 ml/min
* Atrial fibrillation or other persistence cardiac arrythmia
* Contraindication to betablockers (bronchospasm, LVEF less than 40%)
* Implanted PM or ICD
* Previous mechanical heart valve surgery
* Inability to maintain breath-hold for at least 5 sec
* Patient-related condition resulting the inability of the patient to understand the informed consent form of the study

Primary outcomes:
measure: Diagnostic accuracy of Coronary Subtraction Coronary CT angiography
timeFrame: Within 90 days of ICA and CCTA
Secondary outcomes:
measure: Coronary CT angiography reader confidence
timeFrame: Within 90 days of ICA and CCTA
measure: Coronary stenosis severity in non-diagnostic or partially diagnostic segments by conventional CCTA
timeFrame: Within 90 days of ICA and CCTA
measure: Coronary revascularization
timeFrame: Within 30 days after CCTA
Other outcomes:
Locations:
city: Bethesda
country: United States
facility: National Heart, Lung and Blood Institute
state: Maryland
city: Copenhagen
country: Denmark
facility: Department of Cardiology and Radiology, Rigshospitalet, The Heart Center, Capital Region of Copenhagen, University of Copenhagen
Study officials:
affiliation: Rigshospitalet, University of Copenhagen, Denmark
name: Klaus F Kofoed, MD, DmSc
role: PRINCIPAL_INVESTIGATOR
References:
citation: Abdulla J, Pedersen KS, Budoff M, Kofoed KF. Influence of coronary calcification on the diagnostic accuracy of 64-slice computed tomography coronary angiography: a systematic review and meta-analysis. Int J Cardiovasc Imaging. 2012 Apr;28(4):943-53. doi: 10.1007/s10554-011-9902-6. Epub 2011 Jun 12.
citation: Tanaka R, Yoshioka K, Muranaka K, Chiba T, Ueda T, Sasaki T, Fusazaki T, Ehara S. Improved evaluation of calcified segments on coronary CT angiography: a feasibility study of coronary calcium subtraction. Int J Cardiovasc Imaging. 2013 Dec;29 Suppl 2:75-81. doi: 10.1007/s10554-013-0316-5. Epub 2013 Oct 25.
citation: Fuchs A, Kuhl JT, Chen MY, Helqvist S, Razeto M, Arakita K, Steveson C, Arai AE, Kofoed KF. Feasibility of coronary calcium and stent image subtraction using 320-detector row CT angiography. J Cardiovasc Comput Tomogr. 2015 Sep-Oct;9(5):393-8. doi: 10.1016/j.jcct.2015.03.016. Epub 2015 Apr 16.