Abstract
Background:
Patients presenting to the Emergency Department (ED) with chest pain who have an indeterminate (detectable to mildly elevated) troponin are often evaluated with tests that use ionizing radiation. We hypothesized that patients initially evaluated with stress cardiac magnetic resonance (CMR) imaging receive less ionizing radiation through one year of follow-up than those initially evaluated with invasive angiography.
Methods:
We conducted a secondary analysis of the CMR-IMPACT trial, which randomized adult patients at 4 U.S. sites (9/2013-7/2018) with a contemporary troponin of 0.006-1.0 ng/mL to either CMR imaging or invasive angiography. Cumulative radiation exposure from coronary computed tomography angiography, nuclear medicine stress imaging, cardiac catheterization, and percutaneous coronary intervention was assessed from index through one year using validated radiation dose estimates. Radiation doses at index and one year were compared between arms using linear regression adjusted for the stratification factors of initial troponin and known coronary artery disease in both intention-to-treat (ITT) and per-protocol (PP) populations.
Results:
During the study period, 312 patients were enrolled, with 156 randomized to each arm (CMR vs. invasive angiography). In the ITT analysis, patients in the CMR arm had less radiation exposure at index compared to patients in the invasive angiography arm (4.7±5.7 mSv vs. 7.8±5.8 mSv; p<0.001). The difference in radiation exposure at one year was 7.5±10.9 mSv vs. 9.5±8.4 mSv (p=0.06). In the PP analysis, patients receiving CMR (N=102) had less radiation exposure than those receiving invasive angiography (N=104) at index (3.5±5.1 mSv vs. 9.3±3.7 mSv; p<0.001) and one year (5.8±10.9 mSv vs. 11.2±8.1 mSv; p<0.001).
Conclusion:
CMR was associated with decreased radiation exposure compared to invasive angiography.
Keywords: chest pain, risk stratification, radiation, cardiac magnetic resonance
INTRODUCTION
Emergency department (ED) patients presenting with acute chest pain who have an indeterminate (detectable to mildly elevated) troponin are often evaluated with cardiac imaging modalities that rely on ionizing radiation, such as nuclear medicine stress imaging and invasive angiography.1–3 This radiation exposure has known health implications to patients and medical personnel. For example, the ISCHEMIA trial suggests that patients receiving invasive angiography have nearly double the number of cancer-related deaths compared to those who do not receive invasive angiography.4
Our team recently conducted the Cardiac Magnetic Resonance Imaging Strategy for the Management of Patients with Acute Chest Pain and Detectable to Elevated Troponin’ (CMR-IMPACT) trial.1 We found that a cardiac magnetic resonance (CMR)-based evaluation strategy resulted in similar clinical outcomes compared to an invasive angiography-based strategy. Given that CMR does not expose patients to ionizing radiation, it is anticipated that a CMR-based strategy is associated with decreased radiation exposure compared to an invasive angiography-based strategy at the index visit. However, there is limited data evaluating radiation exposure differences between these strategies and it is unknown whether upfront radiation reductions using CMR at the index visit are maintained through one year of follow-up.
To address this gap in evidence, we conducted a secondary analysis of the CMR-IMPACT trial. We hypothesized that a CMR-based strategy would be associated with less radiation exposure among study participants. We aimed to determine and compare exposure to ionizing radiation at the index encounter through one year of follow-up between the CMR-based and invasive-based strategies among participants in the CMR-IMPACT trial.
METHODS
Study Design and Setting
We conducted a secondary analysis of the CMR-IMPACT randomized, controlled, multicenter center clinical trial funded by the National Institutes of Health (R01HL118263) (ClinicalTrials.gov: NCT01931852).1 The study was approved by the institutional review board at each clinical site. Four high-volume U.S. academic tertiary care centers with advanced cardiac imaging capabilities participated. Each site routinely used CMR and invasive angiography. Participants provided written consent prior to being randomized to an invasive-based or CMR-based strategy. The methods of the trial have been described in detail in prior publications.1,3,5
Participants
Patients ≥21 years old evaluated in the ED for possible acute coronary syndrome (ACS) who had at least one serum troponin value between the lower limit of detection and 1.0 ng/mL were screened for eligibility. Patients were ineligible for randomization if they completed stress testing or coronary angiography before enrollment, a troponin >1.0 ng/mL resulted before consent, they had ST-segment elevation (≥1 mm) or ST-segment depression (≥2 mm) on their electrocardiogram, were hemodynamically unstable, had ongoing chest pain requiring emergent cardiac catheterization, had known severe multivessel coronary artery disease previously determined to be not amenable to mechanical intervention, coronary revascularization in the past 6 months, contraindications to CMR stress imaging, life expectancy <6 months, creatinine clearance <30 mL/min, hepatorenal syndrome or chronic liver disease with creatine clearance <60 mL/min, or prior solid organ transplant.
Randomization
After obtaining written consent, participants were stratified based on the presence of known coronary artery disease (≥50% stenosis, prior myocardial infarction, revascularization, positive stress without follow-up catheterization) and the most recent troponin measure (elevated or not elevated above the 99th percentile of the upper reference limit of the local troponin assay). Participants were randomized within strata to one of the 2 treatment arms with equal probability using random permuted block randomization.
Procedures
If assigned to an invasive-based strategy, participants were evaluated by the admitting or consulting cardiology team and underwent invasive angiography, if deemed appropriate. Participants assigned to a CMR-stress diagnostic pathway were similarly evaluated by the admitting team, and if deemed appropriate, underwent CMR stress imaging using gadolinium. While being evaluated for ACS, the admitting team was permitted to obtain other cardiac imaging studies, such as coronary computed tomography angiography (CCTA) and nuclear medicine stress imaging.
Data Collection
Demographics, cardiovascular disease risk factors, and troponin measures were collected at the index encounter. We also captured cardiovascular imaging tests and procedures known to confer ionizing radiation: nuclear medicine stress imaging, CCTA, invasive coronary angiography, and percutaneous coronary intervention (PCI). Data collection templates were used to prospectively collect data from patients, unless the data element was reliably available in the electronic health record. The electronic health record was then surveilled to determine if patients had any subsequent cardiovascular testing or procedures during the one-year follow-up period. Data were entered into a Web-based clinical trial data management system.
Outcomes
The study outcome was radiation exposure, measured in millisieverts (mSv). Average radiation exposure estimates, previously described by the PROMISE trial investigators, for invasive coronary angiography and other diagnostic cardiac imaging studies were used.6 A radiation exposure of 7.0 mSv was imputed for invasive coronary angiography, 15.0 mSv for PCI, 12.2 mSv for nuclear medicine stress imaging studies, and 6.6 mSv for CCTA studies.6
Statistical Analysis
Patient demographics, risk factors, and diagnostic cardiac imaging and procedures are described using means and standard deviations or frequencies and percentages. Cumulative radiation exposure per patient from nuclear medicine stress imaging, CCTA, cardiac catheterization, and PCI was assessed from index through one year using validated radiation dose estimates.6 Radiation exposure per patient is reported numerically with both means and standard deviations and medians and interquartile ranges (IQR) and graphically with boxplots. Line graphs are used to display the accumulation of radiation over time by arm (CMR vs. invasive). Radiation doses per patient at index and one year were compared between arms using linear regression adjusted for the stratification factors of initial troponin and known coronary artery disease in both intention-to-treat and per-protocol populations. In the per-protocol analysis, only patients who received the intended study intervention (invasive angiography or CMR) were included. Additional details regarding the intention-to-treat and per-protocol populations are available in the supplemental methods of the primary publication.1
RESULTS
During the study period, 312 patients were enrolled, with 156 randomized to each study arm (CMR-based and invasive-based strategies). The participants were 59.9% (187/312) male, 64.0% (199/312) White, and had an average age of 60.6 ± 11.3 years. At one year, this cohort of 312 patients had 270 cardiac imaging studies with ionizing radiation, consisting of 31 nuclear medicine stress imaging studies, 12 CCTAs, 152 invasive coronary angiograms, and 75 PCIs. Table 1 further describes the study sample. Table 2 describes the cardiac tests performed at index and one year.
Table 1.
Patient Characteristics
| Patient Characteristics |
Invasive-based Strategy n=156 n (%) |
CMR-based Strategy n=156 n (%) |
Total N=312 n (%) |
|---|---|---|---|
| Age (years) (mean ± SD) | 60.0 ±11.9 | 61.2 ± 10.7 | 60.6 ± 11.3 |
| Male sex | 83 (53.2%) | 104 (66.7%) | 187 (59.9%) |
| Ethnicity: Hispanic or Latinx | 1 (0.6%) | 2 (1.3%) | 3 (1.0%) |
| Race* | |||
| Native American | 0 (0.0%) | 1 (0.6%) | 1 (0.3%) |
| Asian | 0 (0.0%) | 2 (1.3%) | 2 (0.6%) |
| Pacific Islander | 0 (0.0%) | 1 (0.6%) | 1 (0.3%) |
| African American | 57 (36.5%) | 49 (31.6%) | 106 (34.1%) |
| White | 98 (62.8%) | 101 (65.2%) | 199 (64.0%) |
| Other | 1 (0.6%) | 1 (0.6%) | 2 (0.6%) |
| Comorbidities | |||
| Smoking Status* | |||
| Never | 57 (37.0%) | 56 (35.9%) | 113 (36.5%) |
| Current | 48 (31.2%) | 48 (30.8%) | 96 (31.0%) |
| Former | 49 (31.8%) | 52 (33.3%) | 101 (32.6%) |
| Hypertension | 117 (75.0%) | 121 (77.6%) | 238 (76.3%) |
| Diabetes | 60 (38.5%) | 52 (33.3%) | 112 (35.9%) |
| Hyperlipidemia | 92 (59.0%) | 94 (60.3%) | 186 (59.6%) |
| Congestive heart failure | 22 (14.1%) | 17 (10.9%) | 39 (12.5%) |
| Coronary artery disease | 64 (41.0%) | 64 (41.0%) | 128 (41.0%) |
| Cerebral vascular accident | 21 (13.5%) | 13 (8.3%) | 34 (10.9%) |
| Peripheral vascular disease* | 14 (9.0%) | 14 (9.0%) | 28 (9.0%) |
CMR – cardiac magnetic resonance imaging, SD – standard deviation, IQR – interquartile range
One patient in the CMR arm is missing race, 2 patients in the invasive arm are missing smoking status, and 2 patients are missing information on peripheral vascular disease (1 in each arm)
Table 2.
Cardiac imaging and procedures performed at index and through one year of follow-up.
| Intention-to-Treat | Per-Protocol | |||||
|---|---|---|---|---|---|---|
| Invasive-based Strategy n=154 tests n (%) |
CMR-based Strategy n=116 tests n (%) |
Total N=270 tests n (%) |
Invasive-based Strategy n=126 tests n (%) |
CMR-based Strategy n=60 tests n (%) |
Total N=186 tests n (%) |
|
| Index | ||||||
| Nuclear Medicine Stress Imaging | 14 (9.1) | 2 (1.7) | 16 (5.9) | 1 (0.8) | 0 (0) | 1 (0.5) |
| CCTA | 5 (3.2) | 6 (5.2) | 11 (4.1) | 1 (0.8) | 4 (6.7) | 5 (2.7) |
| Invasive Coronary Angiography | 79 (51.3) | 42 (3.6) | 121 (44.8) | 77 (61.1) | 23 (38.3) | 100 (53.8) |
| Percutaneous Coronary Intervention | 31 (20.1) | 25 (21.6) | 56 (20.7) | 27 (21.4) | 11 (18.3) | 38 (20.4) |
| One Year (inclusive of index) | ||||||
| Nuclear Medicine Stress Imaging | 20 (13.0) | 11 (9.5) | 31 (11.5) | 5 (4.0) | 7 (11.7) | 12 (6.5) |
| CCTA | 5 (3.3) | 7 (6.0) | 12 (4.4) | 1 (0.8) | 4 (6.7) | 5 (2.7) |
| Invasive Coronary Angiography | 92 (59.7) | 60 (51.7) | 152 (56.3) | 88 (69.8) | 32 (53.3) | 120 (64.5) |
| Percutaneous Coronary Intervention | 37 (24.0) | 38 (32.8) | 75 (27.8) | 32 (25.4) | 17 (28.3) | 49 (26.3) |
Patients could have received multiple tests or interventions.
CCTA – coronary computed tomography angiography, CMR – cardiac magnetic resonance imaging
In the intention-to-treat analysis, the mean radiation doses for invasive group participants were 7.8±5.8 mSv during the index visit and 9.5±8.4 mSv through one year of follow-up. The mean radiation exposure for CMR participants was 4.7±5.7 mSv at index and 7.8±5.8 mSv through one year. The absolute reduction in radiation exposure associated with the CMR-based approach was −3.2 mSv (95% CI −4.4 to −2.0, p<0.001) at index and −2.1 mSv (95%CI −4.2 to 0.1, p=0.06) through one year. Table 3 and Figure 1 further describe radiation exposure per patient at index and through one year of follow-up when analyzed as randomized. Figure 2 shows the cumulative radiation exposure by strata through one year of follow-up in the intention-to-treat population.
Table 3.
Radiation doses (mSv) at index and through one year of follow-up.
| Intention-to-Treat | ||||
|---|---|---|---|---|
| Radiation Dose (mSv) | Invasive-based n=156 |
CMR-based n=156 |
Estimate (95% CI)* | p-value |
|
| ||||
| Index | −3.2 (−4.4 to −2.0) | <0.001 | ||
| Mean (SD) | 7.8 (5.8) | 4.7 (5.7) | ||
| Median (IQR) | 7.0 (7.0-12.2) | 0 (0-7.0) | ||
|
| ||||
| One Year (inclusive of index) | −2.1 (−4.2 to 0.1) | 0.06 | ||
| Mean (SD) | 9.5 (8.4) | 7.5 (10.9) | ||
| Median (IQR) | 7.0 (7.0-14.5) | 7.0 (0-12.2) | ||
|
| ||||
| Per-Protocol | ||||
| Radiation Dose (mSv) | Invasive-based n=104 |
CMR-based n=102 |
Estimate (95% CI)* | p-value |
|
| ||||
| Index | −5.7 (−6.9 to −4.5) | <0.001 | ||
| Mean (SD) | 9.3 (3.7) | 3.5 (5.1) | ||
| Median (IQR) | 7.0 (7.0-15.0) | 0 (0-7.0) | ||
|
| ||||
| One Year (inclusive of index) | −5.3 (−7.9 to −2.7) | <0.001 | ||
| Mean (SD) | 11.2 (8.1) | 5.8 (10.9) | ||
| Median (IQR) | 7.0 (7.0-15.0) | 0 (0-7.0) | ||
Regression estimate from a linear regression model comparing CMR-based to invasive-based; adjusted for the stratification factors of initial troponin and known coronary artery disease
CMR – cardiac magnetic resonance imaging, SD – standard deviation, IQR – interquartile range, CI – confidence interval
Figure 1.
Radiation exposure per patient at index and through one year of follow-up by strata in the intention-to-treat and per-protocol populations.
Figure 2.
Cumulative radiation exposure by arm in the intention-to-treat and per-protocol populations.
In the per-protocol analysis, mean radiation doses for invasive group participants were 9.3±3.7 mSv during the index visit and 11.2±8.1 mSv through one year of follow-up. Mean radiation exposure for CMR-based participants was 3.5±5.1 mSv at index and 5.8±10.9 mSv through one year. The absolute reduction in radiation exposure associated with the CMR-based approach was −5.7 mSv (95% CI −6.9 to −4.5, p<0.001) at index and −5.31 mSv (95%CI −7.9 to −2.7, p<0.001) through one year. Table 3 and Figure 1 further describe radiation exposure per patient at index and through one year of follow-up per-protocol. Figure 2 shows the cumulative radiation exposure by strata through one year of follow-up in the intention-to-treat population.
DISCUSSION
This secondary analysis of the CMR-IMPACT randomized controlled trial evaluated and compared radiation exposure at index through one year of follow-up among ED patients with possible ACS who were evaluated with either a CMR-based strategy or an invasive-based strategy. We found that patients evaluated with the CMR-based strategy had less radiation exposure at index and through one year of follow-up. Given the iatrogenic harm associated with radiation, clinicians should thoughtfully consider the radiation associated with each care strategy when determining the best approach for patients.
Cumulative radiation exposure across a variety of cardiac imaging modalities has been previously reported. For example, investigators from the PROMISE Trial found among patients being evaluated for ACS, those who had their care guided by CCTA had less index and 90-day cumulative radiation than those receiving care guided by nuclear stress imaging.2 Similarly, our analysis revealed a potentially clinically significant decrease in radiation for participants in the CMR-based group. We observed an absolute reduction in radiation of more than 5 mSv in the CMR-based strategy compared to the invasive-based strategy in our per-protocol population.
The modest reduction in radiation exposure associated with a CMR-based strategy is relevant to broader considerations about radiation safety. Radiation exposure during diagnostic and therapeutic interventions carries health implications to the patients undergoing testing and to the clinicians performing them. According to the National Academy of Sciences 7th Biological Effects of Ionizing Radiation report, cancer risk in humans is difficult to evaluate at doses <100 mSv.8 However, the linear no-threshold model posits that any radiation poses a potential cancer risk, regardless of how small the dose.9,10 Therefore, considerable effort has been made to decrease radiation exposure during diagnostic imaging and procedures while preserving image quality and diagnostic accuracy, or at doses “as low as reasonably achievable” (ALARA).11–13 Joint safety guidelines recommend ALARA principles to minimize risk to patients as well as healthcare workers at higher risk for occupational exposures.14–17 Therefore, a CMR-based approach for patients with acute chest pain is consistent with safety efforts to decrease radiation exposure.
The population level benefits from reducing cumulative exposure to ionizing radiation may be substantial. Given that the CMR-based strategy was associated with nearly 5 mSv less radiation exposure at one year compared to the invasive strategy, a CMR-based approach could prevent 1 cancer per every 5,000 patients.18 Because >1 million invasive cardiac catheterizations are performed annually, a CMR-based strategy could prevent about 200 cancers in the U.S. each year.19 This aligns with the need for ongoing radiological awareness among clinicians and more informed conversations with patients about the radiation risks associated with medical testing.20–22 If safe and effective alternatives are available, such as CMR, safety advocates have highlighted a need for increased patient participation in decision-making and informed consent.23–25 The findings from this secondary analysis add to the growing body of literature regarding iatrogenic radiation exposure and may be useful for clinicians in their shared decision making conversations with patients.
While the CMR-based strategy was associated with less radiation exposure at index and at one year in the per-protocol population, the difference in index radiation exposure was not maintained at one year in the intention-to-treat population. Although not a statistically significant difference, the point estimate and confidence interval (−2.1 mSv, 95%CI −4.2 to 0.1 mSv) for absolute reduction in radiation at one year in the intention-to-treat population suggests that a CMR-based approach may be associated with lower radiation exposure. While the sample size is modest, there was a high-frequency of study arm non-adherence in the CMR-IMPACT trial. This was likely driven by patients being randomized after their first troponin result. After randomization, new clinically pertinent information became available (such as additional troponin measures) and could be used by the care team to alter the care approach. This non-adherence likely drives the difference in findings between the intention-to-treat and per-protocol populations at the person level. Furthermore, when comparing the cumulative radiation exposure between arms, the CMR-based strategy was clearly associated with less radiation exposure in both the intention-to-treat and per-protocol populations.
LIMITATIONS
There are limitations associated with this analysis. The study was conducted at four academic medical centers in the United States, which may make the results difficult to generalize across other medical facilities. Although we imputed radiation dose estimates, we relied on validated estimates used in prior cardiovascular studies, including the PROMISE Trial.6 While we did not differentiate radial vs. femoral artery access site for cardiac catheterizations, prior literature indicates that radiation exposure is similar between these two sites.25 Radiation exposure is an important surrogate marker. However, we are unable to report on patient-centered outcomes (i.e., cancer diagnoses) related to radiation exposure given the sample size and duration of follow-up.
CONCLUSION
Compared to an invasive approach when evaluating patients with possible ACS who have an indeterminate initial troponin measure, patients managed initially with CMR experienced less radiation exposure at index and through one year of follow-up. These findings suggest that the favorable radiation safety profile associated with CMR utilization may be an important factor to consider when evaluating patients for possible ACS. Future research is needed to quantify the potential real-world harm associated with cardiac imaging and procedures.
ACKNOWLEDGEMENTS
We would like to thank Michael Kutcher MD, Alan Jones MD, Michael Hall MD, and Lauren Koehler MS for their assistance with this project.
Funding:
CMR-IMPACT received funding from NIH (R01HL118263), Siemens, and Abbott.
Additional Authors in the CMR-IMPACT Research Group Include: Subha V. Raman MD1; Jeffrey M. Caterino MD2; Carol L. Clark MD3; Brian C. Hiestand MD, MPH4
Additional Author Affiliations:
1 OhioHealth, Columbus, OH
2 Department of Emergency Medicine, The Ohio State University, Columbus, OH
3 Department of Emergency Medicine, Corewell Health William Beaumont University Hospital, Royal Oak, MI
4 Department of Emergency Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
REFERENCES
- 1.Miller CD, Mahler SA, Snavely AC, et al. Cardiac Magnetic Resonance Imaging Versus Invasive-Based Strategies in Patients With Chest Pain and Detectable to Mildly Elevated Serum Troponin: A Randomized Clinical Trial. Circ Cardiovasc Imaging. 2023;16(6):e015063. doi: 10.1161/CIRCIMAGING.122.015063 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Mahler SA, Lenoir KM, Wells BJ, et al. Safely Identifying Emergency Department Patients With Acute Chest Pain for Early Discharge. Circulation. 2018;138(22):2456–2468. doi: 10.1161/circulationaha.118.036528 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Supples MW, Snavely AC, Ashburn NP, et al. Cardiac testing choices by physician specialty in the CMR-IMPACT trial. Am J Emerg Med. 2025;90:200–204. doi: 10.1016/j.ajem.2025.01.073 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Sidhu MS, Alexander KP, Huang Z, et al. Causes of cardiovascular and noncardiovascular death in the ISCHEMIA trial. Am Heart J. 2022;248:72–83. doi: 10.1016/j.ahj.2022.01.017 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Boyer LM, Snavely AC, Stopyra JP, et al. Sex and race disparities in emergency department patients with chest pain and a detectable or mildly elevated troponin. Am Heart J Plus. 2025;49(100495):100495. doi: 10.1016/j.ahjo.2024.100495 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Lu MT, Douglas PS, Udelson JE, et al. Safety of coronary CT angiography and functional testing for stable chest pain in the PROMISE trial: A randomized comparison of test complications, incidental findings, and radiation dose. J Cardiovasc Comput Tomogr. 2017;11(5):373–382. doi: 10.1016/j.jcct.2017.08.005 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.National Research Council, Division on Earth and Life Studies, Board on Radiation Effects Research, Committee to Assess Health Risks from Exposure to Low Levels of Ionizing Radiation. Health Risks from Exposure to Low Levels of Ionizing Radiation. National Academies Press; 2006. doi: 10.17226/11340 [DOI] [Google Scholar]
- 8.Shamoun DY. Linear No-Threshold model and standards for protection against radiation. Regul Toxicol Pharmacol. 2016;77:49–53. doi: 10.1016/j.yrtph.2016.02.011 [DOI] [PubMed] [Google Scholar]
- 9.De Lanerolle G, Roberts ES, Haroon A, Shetty A. Clinical and translational radiology. In: Quality Assurance Management. Elsevier; 2024:241–307. doi: 10.1016/b978-0-12-822732-9.00005-9 [DOI] [Google Scholar]
- 10.Small GR, Chow BJW, Ruddy TD. Low-dose cardiac imaging: reducing exposure but not accuracy. Expert Rev Cardiovasc Ther. 2012;10(1):89–104. doi: 10.1586/erc.11.173 [DOI] [PubMed] [Google Scholar]
- 11.Entrikin DW, Leipsic JA, Carr JJ. Optimization of radiation dose reduction in cardiac computed tomographic angiography. Cardiol Rev. 2011;19(4):163–176. doi: 10.1097/CRD.0b013e31821daa8f [DOI] [PubMed] [Google Scholar]
- 12.Hirshfeld JW Jr, Ferrari VA, Bengel FM, et al. 2018 ACC/HRS/NASCI/SCAI/SCCT expert consensus document on optimal use of ionizing radiation in cardiovascular imaging: Best practices for safety and effectiveness. J Am Coll Cardiol. 2018;71(24):e283–e351. doi: 10.1016/j.jacc.2018.02.016 [DOI] [PubMed] [Google Scholar]
- 13.Miller DL, Vañó E, Bartal G, et al. Occupational radiation protection in interventional radiology: a joint guideline of the Cardiovascular and Interventional Radiology Society of Europe and the Society of Interventional Radiology. J Vasc Interv Radiol. 2010;21(5):607–615. doi: 10.1016/j.jvir.2010.01.007 [DOI] [PubMed] [Google Scholar]
- 14.Tamirisa KP, Alasnag M, Calvert P, et al. Radiation exposure, training, and safety in cardiology. JACC Adv. 2024;3(4):100863. doi: 10.1016/j.jacadv.2024.100863 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15.Fetterly KA, Mathew V, Lennon R, Bell MR, Holmes DR Jr, Rihal CS. Radiation dose reduction in the invasive cardiovascular laboratory: implementing a culture and philosophy of radiation safety. JACC Cardiovasc Interv. 2012;5(8):866–873. doi: 10.1016/j.jcin.2012.05.003 [DOI] [PubMed] [Google Scholar]
- 16.Uffmann M, Schaefer-Prokop C. Digital radiography: the balance between image quality and required radiation dose. Eur J Radiol. 2009;72(2):202–208. doi: 10.1016/j.ejrad.2009.05.060 [DOI] [PubMed] [Google Scholar]
- 17.X-Ray Risk. Accessed August 8, 2025. https://www.xrayrisk.com/index.php
- 18.Writing Group Members, Mozaffarian D, Benjamin EJ, et al. Heart disease and stroke statistics-2016 update: A report from the American heart association: A report from the American heart association. Circulation. 2016;133(4):e38–360. doi: 10.1161/CIR.0000000000000350 [DOI] [PubMed] [Google Scholar]
- 19.Carpeggiani C, Picano E. The radiology informed consent form: recommendations from the European Society of Cardiology position paper. J Radiol Prot. 2016;36(2):S175–86. doi: 10.1088/0952-4746/36/2/S175 [DOI] [PubMed] [Google Scholar]
- 20.Semelka RC, Armao DM, Elias J Jr, Picano E. The information imperative: is it time for an informed consent process explaining the risks of medical radiation? Radiology. 2012;262(1):15–18. doi: 10.1148/radiol.11110616 [DOI] [PubMed] [Google Scholar]
- 21.Picano E. Informed consent and communication of risk from radiological and nuclear medicine examinations: how to escape from a communication inferno. BMJ. 2004;329(7470):849–851. doi: 10.1136/bmj.329.7470.849 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Stickrath C, Druck J, Hensley N, Maddox TM, Richlie D. Patient and health care provider discussions about the risks of medical imaging: not ready for prime time. Arch Intern Med. 2012;172(13):1037–1038. doi: 10.1001/archinternmed.2012.1791 [DOI] [PubMed] [Google Scholar]
- 23.Ludwig RL, Turner LW. Effective patient education in medical imaging: public perceptions of radiation exposure risk. J Allied Health. 2002;31(3):159–164. https://www.ncbi.nlm.nih.gov/pubmed/12227267 [PubMed] [Google Scholar]
- 24.Berlin L. Shared decision-making: is it time to obtain informed consent before radiologic examinations utilizing ionizing radiation? Legal and ethical implications. J Am Coll Radiol. 2014;11(3):246–251. doi: 10.1016/j.jacr.2013.10.006 [DOI] [PubMed] [Google Scholar]
- 25.Gray B, Klimis H, Inam S, et al. Radiation exposure during cardiac catheterisation is similar for both femoral and radial approaches. Heart Lung Circ. 2015;24(3):264–269. doi: 10.1016/j.hlc.2014.09.022 [DOI] [PubMed] [Google Scholar]