Chest Pain, Coronary Artery Disease
Conditions
Keywords
radiation, cardiac computed tomography, CCTA, breast shielding, Myocardial perfusion scintigraphy, MPS, Invasive coronary angiography, ICA
Brief summary
Purpose 1. 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. 2. To estimate whether the use of breast shields in cardiac computed tomographic angiography (CCTA) limits the effective radiation exposure of breast tissue.
Detailed description
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.
Interventions
RADIATIONCCTA ~ BREAST SHIELDS
Breast shield placement (randomized) among women.
Sponsors
Walter Reed National Military Medical Center
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Excess Double-strand DNA Break Foci Per Cell in Peripheral Blood Samples Post-imaging | Change from baseline double strand DNA breaks at 30 minutes 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. |
Participant flow
Pre-assignment details
101 patients enrolled in intervention arms (breast shields). Other patients in observational arm (not completed analysis).
Participants by arm
| Arm | Count |
|---|---|
| CCTA Breast Shields Within female subset, randomization to wearing bismuth breast shield. | 50 |
| CCTA No Breast Shields Within female subset, randomization to not wearing bismuth breast shield (standard of care). | 51 |
| Observational Arm 1\. Non-female patients undergoing coronary CTA; 2. Patients undergoing nuclear cardiology stress testing; 3. Patients undergoing invasive coronary angiography. | 127 |
| Total | 228 |
Baseline characteristics
| Characteristic | Total | Observational Arm | CCTA No Breast Shields | CCTA Breast Shields |
|---|---|---|---|---|
| Age, Continuous | 52 years STANDARD_DEVIATION 14 | 51 years STANDARD_DEVIATION 12 | 51 years STANDARD_DEVIATION 14 | 52 years STANDARD_DEVIATION 14 |
| BMI (kg/m^2) | 27.9 kg/m^2 STANDARD_DEVIATION 5.5 | 27.3 kg/m^2 STANDARD_DEVIATION 5 | 28.1 kg/m^2 STANDARD_DEVIATION 4.5 | 27.6 kg/m^2 STANDARD_DEVIATION 6.3 |
| Chest circumference (cm) | 97.7 cm STANDARD_DEVIATION 11.1 | 97.7 cm STANDARD_DEVIATION 11 | 97.8 cm STANDARD_DEVIATION 10.5 | 97.6 cm STANDARD_DEVIATION 11.7 |
| Current smokers | 27 Participants | 15 Participants | 7 Participants | 5 Participants |
| Ethnicity (NIH/OMB) Hispanic or Latino | 14 Participants | 7 Participants | 3 Participants | 4 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 209 Participants | 115 Participants | 48 Participants | 46 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 5 Participants | 5 Participants | 0 Participants | 0 Participants |
| Heart rate (beats/min) | 55.7 beats/min STANDARD_DEVIATION 6.6 | 64 beats/min STANDARD_DEVIATION 9 | 56.2 beats/min STANDARD_DEVIATION 7.4 | 55.2 beats/min STANDARD_DEVIATION 5.6 |
| Sex: Female, Male Female | 193 Participants | 92 Participants | 51 Participants | 50 Participants |
| Sex: Female, Male Male | 35 Participants | 35 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — | — / — |
| other Total, other adverse events | 0 / 50 | 0 / 51 | 0 / 127 |
| serious Total, serious adverse events | 0 / 50 | 0 / 51 | 0 / 127 |
Outcome results
Primary
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.
Time frame: Change from baseline double strand DNA breaks at 30 minutes post-imaging
Population: Female patients 18 years or older who were clinically referred to undergo coronary CT angiography between August 2012 and July 2014 at Walter Reed National Military Medical Center (Bethesda, Maryland) were eligible for enrollment.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| No Breast Shields | Number of Excess Double-strand DNA Break Foci Per Cell in Peripheral Blood Samples Post-imaging | 0.183 gamma-H2AX foci in blood lymphocytes | Standard Deviation 0.114 |
| Breast Shields | Number of Excess Double-strand DNA Break Foci Per Cell in Peripheral Blood Samples Post-imaging | 0.159 gamma-H2AX foci in blood lymphocytes | Standard Deviation 0.139 |
p-value: <0.05Regression, Linear