The Comparative Study of OCT，Gemstone CT and 320-detector Row Spiral CT for Evaluating Restenosis of Coronary Artery Stent

Study Overview
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Brief Summary
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In-stent restenosis is a major reason of coronary heart disease recurrence .Even in drug eluting stent(DES), Restenosis rate could be up to 10% in diabetes and complex lesions though it was about 3-5% in general. It is particularly important that in-stent restenosis after implantation was early diagnosed and detected. The evaluation of OCT imaging is more accurate for narrow area calculation, more clear for narrow organization structure and more specific for detecting tissue types.It is currently the best way for restenosis histologic diagnosis.But it has many weakness such as the higher cost,an invasive test, expensive instrument, relatively complicated to operate,and etc.In this study, OCT image was regard as the gold standard of stent restenosis. The improvement of spatial resolution of Gemstone CT can effectively improve the imaging quality and the measurement's accuracy of coronary artery stents.The diagnostic value of in-stent restenosis of Gemstone CT is higher than of the 320-detector row spiral CT. To a certain extent, the gemstone CT can replace OCT for examining the in-stent restenosis. This study will examine the degree of in-stent restenosis by the gemstone CT and the 320-detector row spiral CT and compare the two ways on the basis of the result of OCT.

Official Title
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The Comparative Study of OCT，Gemstone CT and 320-detector Row Spiral CT for Evaluating Restenosis of Coronary Artery Stent

Conditions
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Coronary Heart Disease

Intervention / Treatment
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* Device: CT image for patient with suspected in-stent restenosis


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 20-80， All genders Unlimited time of implantation of coronary artery stents Myocardial ischemia symptoms such as Chest tightness and/or chest pain in patients after stent implantation No clinical symptoms, but myocardial ischemia suggested by other noninvasive tests Routine re-testing 9-12 months after stent implantation. Exclusion Criteria: Renal insufficiency (serum creatinine > 120 umol/L) Allergy of contrast Severe heart failure Uncontrollable heart rate or contraindication of taking metoprolol Unstable condition the ventricular rate beyond 70 beats / min and irregular rhythm after adjusting.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 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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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Gemstone CT<br>Gemstone CT ：Discovery CT750 HD（high definition） ，GE（General Electric Co.） Healthcare, Milwaukee； CT image for patient with suspected in-stent restenosis which Gemstone CT or 320-detector row spiral CT was assigned randomly to patient | Device: CT image for patient with suspected in-stent restenosis<br>* Gemstone CT or 320-detector row spiral CT was assigned randomly to patient who was suspected in-stent restenosis.About after 10 days,they would accept the check of OCT which wold be the gold standard of in-stent restenosis.<br>* Other names: OCT;|
| Active Comparator: 320-detector row spiral CT<br>320-detector row spiral CT：Aquilion One, Toshiba, Nasu, Japan. CT image for patient with suspected in-stent restenosis which Gemstone CT or 320-detector row spiral CT was assigned randomly to patient . | Device: CT image for patient with suspected in-stent restenosis<br>* Gemstone CT or 320-detector row spiral CT was assigned randomly to patient who was suspected in-stent restenosis.About after 10 days,they would accept the check of OCT which wold be the gold standard of in-stent restenosis.<br>* Other names: OCT;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Accuracy of detection of in-stent restenosis with the gemstone CT as compared to the 320-detector row spiral CT will be investigated | Masked examiners (CT specialists) will evaluate and compare the degree of in-stent restenosis of the gemstone CT and the 320-detector row spiral CT images for the presence and features of in-stent restenosis. In this study, OCT image was regard as the gold standard of in-stent restenosis. | On the day in which a patient receives the gemstone CT and the 320-detector row spiral CT, estimated to take 10 mins | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radiation burden of the the gemstone CT or the 320-detector row spiral CT and OCT | In a relatively short time,the patient will accept the two checks of CT and OCT(Interval period about 10 days).So,it is necessary to clear the reacts of these patients | one month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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gemstone CT, 320-detector row spiral CT, optical coherence tomography(OCT), in-stent restenosis, coronary heart disease