Characteristics of Culprit Lesion and Changes in Plaque Composition. A Dual Energy Cardiac CT Study

Study Overview
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Brief Summary
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Identifying patients who are at risk for a future myocardial infarction, is still one of the biggest challenges in cardiology. In this study the investigators will investigate culprit lesion in patients with NSTEMI and the ability of cardiac CT with dual energy computed tomography (DECT) scanning to describe and identify plaques that may be vulnerable. The investigators will also describe changes in characteristic in both stable and unstable plaques during 1 year follow up of NSTEMI and a matching group of stable angina pectoris (SAP) patients.

Detailed Description
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Patients with verified NSTEMI undergo contrast-enhanced coronary DECT before conventional coronary angiography (CAG), and DECT characteristics of the culprit lesion will be determined. All Non-culprit lesions will be observed during 2 month and 1 year follow up characteristics and changes in plaque composition, volume and core content will be assessed. Patients with SAP undergo a baseline DECT similar to NSTEMI group. Because the expected change in coronary plaques in SAP group is minimal, there is no need for follow up at 2 month.

Official Title
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Characteristics of Culprit Lesion and Changes in Plaque Composition During Follow up in NSTEMI. A Dual Energy Cardiac CT Study

Conditions
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Coronary Arteriosclerosis

Intervention / Treatment
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* Radiation: Cardiac CT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with NSTEMI and scheduled to CAG or patients with SAP Exclusion Criteria: Not suitable to undergo CT with contrast agent: Known allergy-like reactions to contrast or Claustrophobia Atrial fibrillation or significant arrhythmia judged to potentially limit quality of CT Known renal failure/insufficiency or s-creatinin> 140 µmol/L. Severe/symptomatic thyrotoxicosis pacemaker

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| NSTEMI<br>patients hospitalized with NSTEMI diagnosed according to the national Danish guidelines, and are scheduled to coronary angiography. | Radiation: Cardiac CT<br>* Cardiac CT before the CAG, and follow up after 2 month and 12 month<br>|
| patients with stable angina pectoris<br>Patients in this group have stable angina symptoms and had verified plaques by earlier CAG or Cardiac CT | Radiation: Cardiac CT<br>* Cardiac CT before the CAG, and follow up after 2 month and 12 month<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Description and characteristics of culprit lesion by DECT. (z-value) | measure the z-value for the culprit lesion, by marking the culprit lesion with a region of interest (ROI) and the DECT will calculate the mean z-value by mg/mm^3 in the marked ROI | 72 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Describe if the culprit lesion contains 1: soft 2: mixed or 3: calcified tissue | Visually description if the culprit lesion contain 1: soft tissue (dark area in the scan) 3: calc (white area) or 2: mixed (combined dark and white areas) | 72 hours | 
| Measure the volume of the culprit lesion | CT software will be automatically able to measure the volume (mm3) og culprit lesion | 72 hours | 
| Measure the remodeling index of culprit lesion | CT software will be automatically able to measure the remodeling index in culprit lesion (mm) | 72 hours | 
| Determine the mean Z value for non-culprit plaques containing 1: soft tissue | measure the z-value for the culprit lesion, by marking the lesion with a ROI and the DECT will calculate the mean z-value in the marked ROI | 72 hours | 
| Determine the mean Z value for non-culprit plaques containing 1: soft tissue | measure the z-value for the culprit lesion, by marking the lesion with a ROI and the DECT will calculate the mean z-value mg/mm^3 in the marked ROI | 2 month | 
| Determine the mean Z value for non-culprit plaques containing 1: soft tissue | measure the z-value for the culprit lesion, by marking the lesion with a ROI and the DECT will calculate the mean z-value mg/mm^3 in the marked ROI | 1 year | 
| Determine the mean Z value for non-culprit plaques containing 2: mixed tissue | z-value mg/mm^3 | 72 hours | 
| Determine the mean Z value for non-culprit plaques containing 2: mixed tissue | z-value mg/mm^3 | 2 month | 
| Determine the mean Z value for non-culprit plaques containing 2: mixed tissue | z-value mg/mm^3 | 1 year | 
| Determine the mean Z value for non-culprit plaques containing 3: calcified tissue | z-value mg/mm^3 | 72 hours | 
| Determine the mean Z value for non-culprit plaques containing 3: calcified tissue | z-value mg/mm^3 | 2 month | 
| Determine the mean Z value for non-culprit plaques containing 3: calcified tissue | z-value mg/mm^3 | 1 year | 
| changes in non-culprit plaques during 1 year in comparison til patients with stable angina pectoris | z-value z-value mg/mm^3 | 1 year | 
| z value in myocardium related to culprit vessel compared to z-value in myocardium corresponded to non-culprit vessel | z-value z-value mg/mm^3 | 72 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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culprit lesion, arteriosclerosis, cardiac CT