Effects of Contrast Media Temperature on Image Quality and Clinical Adverse Events in Coronary CTA

Study Overview
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Brief Summary
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Extrinsic prewarming of iodinated CT contrast media (CM) to body temperature reduces viscosity and injection pressures. However, guideline recommendations on the necessity to prewarm iodinated CM are conflicting. And studies examining the effect of extrinsic warming CM for coronary CTA(CCTA) on clinical adverse events and image quality are lack. Enrolled patients of chest pain or coronary artery disease screening were eligible for this a double-blinded, randomized noninferiority trial, and equally allocated into two group randomly: BBT-CM (basic body temperature) group received 37°C CM; RT-CM (room temperature) group received  23°C CM. A state-of-the-art individualized CM (iopamidol at 370 mg I/mL) injection protocol was used, based on body weight.

Official Title
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Department of Radiology

Conditions
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Contrast Media Adverse Reaction

Intervention / Treatment
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* Drug: Iopamidol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Coronary symptomatic patients (i.e., chest pain). Patients for Coronary artery disease screening Exclusion Criteria: Hemodynamic instability Renal insufficiency (estimated glomerular filtration rate <30 mL/min per 1.73 m2) Prior adverse reactions to iodinated CM Age younger than 18 years Inability to place an 18-gauge needle.

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: BBT-CM (basic body temperature) group<br>BBT-CM (basic body temperature) group received contrast media warmed to body temperature (37°C[99°F]) before coronary CTA. | Drug: Iopamidol<br>* A contrast bolus of iopamidol-370 (370 mg I/ml) (iopamidol injection; Consun Pharmaceutical, China) was injected at a ﬂow rate of 4.5-6 mL/s through an 18-20-gauge intravenous antecubital catheter by using a power injector (Ulrich, Germany). The total dose of iopamidol-370 was approximately 0.9 ml /kg body weight.<br>|
| Active Comparator: RT-CM (room temperature) group<br>RT-CM (room temperature) group received contrast media at room temperature ( 23°C [ 73°F]) before coronary CTA. | Drug: Iopamidol<br>* A contrast bolus of iopamidol-370 (370 mg I/ml) (iopamidol injection; Consun Pharmaceutical, China) was injected at a ﬂow rate of 4.5-6 mL/s through an 18-20-gauge intravenous antecubital catheter by using a power injector (Ulrich, Germany). The total dose of iopamidol-370 was approximately 0.9 ml /kg body weight.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vessel Attenuation | Mean attenuation in Hounsfield Units (HU) is based on coronary bifurcation, preferably right coronary artery (RCA), left anterior descending artery (LAD), and left circumflex coronary artery (LCX)). Absolute difference in mean attenuation of coronary vessels between groups was calculated with a two-sided 95% confidence interval of the difference. | Expected within one month after the coronary CTA is performed | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Allergic or allergiclike reaction | Allergic and allergic-like reactions were identified by evaluating notes within the EMR for elements of such reactions specified in nomenclature from the ACR manual. Allergic reactions were recorded according to symptoms of an immune response to the CM, such as feeling cold urticaria or pruritis. | 30 minutes after coronary CTA | 
| Extravasations | The radiology staff recorded an estimate of the volume of extravasated contrast media | Expected during the coronary CTA scan. | 
| Objective image quality - Signal-to-noise ratio(SNR) | mean attenuation of vessel divided by the mean SD | Within one month after the CT is performed | 
| Objective image quality -Contrast-to-noise ratio(CNR) | mean vascular attenuation minus HU of the vessel, divided by the SD of the attenuation of epicardial fat surrounding left main coronary artery and then divided by image noise | Within one month after the CT is performed | 
| CT Dose Index (CTDI)vol | CTDIvol (in mGy) the patient received | Expected during the coronary CTA is performed | 
| Physiologic reactions-Urgency desire | Urgency desire is defined in the questionnaire as the sudden and intense ''urge'' or need to urinate and scored 1=Not at all, 2=A little, 3= Moderately, 4=A great deal, and 5=A very great deal. | Immediately after CT | 
| Body Mass Index | The formula is BMI = kg/m2 , where kg is a person's weight in kilograms and m2 is their height in metres squared. | Right before the scan is performed | 
| Subjective image quality | Rated in consensus on a 5-point Likert scale by two radiologists: 1=excellent (absence of artifacts related to motion or coronary calcification); 2=good (minor artifacts); 3=moderate (considerable artifacts but maintained visualization of the arterial lumen); and 4=poor (non-diagnostic because of severe motion artifacts or severe coronary calcification). | Within one month after the CT is performed | 
| Heart rate | Heart rate (beats per minute) is monitor during the coronary CTA. | During the coronary CTA. | 
| Flow rate | Flow rate of the contrast media in ml/s. | Within one month after the CT is performed | 
| Dose-length product (DLP) | DLP (in mGycm) the patient received | Within one month after the CT is performed | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Computed Tomography Angiography, Low-osmolality contrast media, Image quality, Clinical adverse event