Effects of Heart Imaging Radiation on DNA Double-Stranded Breaks in Blood Lymphocytes and Hair Follicle Cells

Study Overview
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Brief Summary
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Purpose To investigate the effects of cardiac imaging radiation on the induction of DNA double-strand breaks by enumerating gamma-H2AX foci in blood lymphocytes and plucked hair follicle cells. To estimate whether the use of breast shields in cardiac computed tomographic angiography (CCTA) limits the effective radiation exposure of breast tissue.

Detailed Description
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The primary objective of the study is to analyze blood and hair samples from patients undergoing cardiac imaging to estimate radiation exposure levels as well as their biological effects (i.e. to determine the degree of genotoxicity by measuring the amounts of DNA double-strand breaks). The secondary objective is to investigate whether the use of in-plane breast shielding in female patients undergoing CT angiography (CCTA) limits the radiation exposure of breast tissue and subsequent DNA damage in blood lymphocytes and hair follicle cells.

Official Title
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The HEART BREAK Study: Effects of Heart Imaging Radiation on DNA Double-Stranded Breaks in Blood Lymphocytes and Hair Follicle Cells

Conditions
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Coronary Artery Disease, Chest Pain

Intervention / Treatment
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* Radiation: CCTA   BREAST SHIELDS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult male and female adult subjects (age greater than 18 years) Referred for cardiac computed tomography angiography (CCTA), myocardial perfusion scintigraphy (MPS), or diagnostic invasive coronary angiography (ICA). Exclusion Criteria: Female patients that identify themselves as pregnant or have a positive pregnancy test prior to cardiac imaging. History (present or past) of leukemia or lymphoma. History of radiation therapy X-ray examination or scintigraphy within the last 72 hours. History of coronary revascularization (coronary artery bypass grafting or percutaneous coronary intervention) Patients undergoing percutaneous coronary intervention at completion of diagnostic left heart catheterization

Ages Eligible for Study
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Minimum Age: 18 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 |
| --- | --- |
| Active Comparator: CCTA Breast Shields<br>Within female subset, randomization to wearing bismuth breast shield. | Radiation: CCTA   BREAST SHIELDS<br>* Breast shield placement (randomized) among women.<br>* Other names: BISMUTH BREAST SHIELDS;|
| No Intervention: CCTA No Breast Shields<br>Within female subset, randomization to wearing no bismuth breast shield (standard of care). | |
| No Intervention: Observational Arm<br>Non-females undergoing CTA and subjects undergoing cardiac catheterization and nuclear medicine testing. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Excess Double-strand DNA Break Foci Per Cell in Peripheral Blood Samples Post-imaging | The amount of excess DNA double-strand break foci per cell after cardiac computed tomographic angiography (CCTA) in female patients with and without breast shields, minus the amount of foci prior to CCTA. In addition, changes in DNA double-strand breaks from baseline following cardiac testing in the observational arm is being assessed in an observational manner. | Change from baseline double strand DNA breaks at 30 minutes post-imaging | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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radiation, cardiac computed tomography, CCTA, breast shielding, Myocardial perfusion scintigraphy, MPS, Invasive coronary angiography, ICA