Comparisons of Morphological Measurement Between Coronary Computed Tomography and Optical Coherence Tomography

Study Overview
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Brief Summary
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The objective of this study is to evaluate the precision of semi-automated lumen boundary identification from coronary computed tomography angiography (cCTA) by current version of HeartFlow software and the impact on fractional flow reserve (FFRCT) by using optical coherence tomography (OCT) as reference standard.

Detailed Description
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Analysis of cCTA and OCT was conducted under blind in independent organizations. After unblinding the cCTA and OCT case identification number, the OCT image was co-registered to cCTA data. After co-registration of cCTA and OCT lesion locations, the minimal lumen area (MLA) was detected with both modalities. FFROCT was calculated using OCT-updated models in which cCTA-based lumen geometry was replaced by OCT-based lumen geometry. Lesions were grouped according to their severity of calcification (using Agatston score) and minimum lumen diameter.

Conditions
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Coronary Artery Disease

Intervention / Treatment
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* Other: data collection, non-intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Patients who underwent cCTA prior to coronary angiography and OCT within 6 months. Exclusion Criteria: Prior coronary artery bypass graft (CABG) surgery Contraindication to beta blocker agents or nitrates Tachycardia or significant arrhythmia Impaired chronic renal function (eGFR <30) Subjects with known anaphylactic allergy to iodinated contrast material Pregnancy or unknown pregnancy status in subject of childbearing potential Cases with poor OCT or CCTA image for analyzing

Ages Eligible for Study
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Minimum Age: 20 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 |
| --- | --- |
| severity of calcification<br>All vessels were divided into tertile groups according to the severity of coronary calcification evaluated by the Agatston score. | Other: data collection, non-intervention<br> <br> |
| minimal lumen diameter (MLD) ≥1.0 mm<br>All lesions were divided according to an MLD ≥1.0 mm, and <1.0 mm by OCT in order to isolate the lesions which an MLD below the OCT catheter size. | Other: data collection, non-intervention<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between cCTA and OCT for MLA measurements |  | Immediately after OCT scan | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between FFRCT and FFROCT |  | Immediately after OCT scan | 
| Impact of calcification on the agreement of MLA between OCT and cCTA measurement |  | Immediately after OCT scan | 
| Impact of calcification on the agreement of FFR between OCT and cCTA |  | Immediately after OCT scan |