Radiation Safety in the Practice of Cardiology

ACKNOWLEDGEMENTS

Women as One would like to recognize the contributions from Sheila Sahni MD, FACC, FSCAI,
Alaide Chieffo, MD, FESC and Stephen Balter PhD, FAAPM, FACMP, FACR, FSCAI, FSIR for their work on “Radiation Safety in the Practice of Cardiology”

Sheila Sahni, MD, FACC, FSCAI

Sahni Heart Center, Hackensack-Meridian Health, Clark, NJ USA

Alaide Chieffo, MD, FESC

San Raffaele Hospital, Milan, Italy

Stephen Balter, PhD, FAAPM, FACMP, FACR, FSCAI, FSIR

Columbia University, New York, NY, USA

ENDORSEMENTS

Women as One would like to recognize our global partners for their endorsements.

Together, we can amplify our voices to create meaningful change to support women around the world.

OVERVIEW

WHAT THE PREGNANT CARDIOLOGIST NEEDS TO KNOW

(CONSIDERATIONS/GAPS)

RADIATION BASICS AND PROTECTION

RECOMMENDATIONS

Men
Women

LITTLE / NO CHANGE

Career satisfaction remains high
Women are more likely to:
- Experience discrimination
- Require paid/unpaid childcare help

LITTLE / NO CHANGE OVER TWO DECADES

SIGNIFICANT CHANGE

Aging workforce
Practice setting
Men now balancing career and family; less likely to travel professionally

LITTLE / NO CHANGE OVER TWO DECADES

CAREER SATISFACTION

EXPERIENCE DISCRIMINATION

REQUIRE CHILDCARE HELP

1996
2006
2015

50 YEARS AGE AND OLDER

PRIVATE PRACTICE

FAMILY REPONSIBILITIES IMPEDE PROFESSIONAL TRAVEL

1996
2006
2015

Lewis, S.J. et al. J Am Coll Cardiol. 2017;69(4):452-62.
Areas for which there has been minimal or no change in responses to survey questions regarding personal and professional life issues are contrasted with areas where significant changes have occurred.

Yes
No

CARDIOLOGISTS UNDER 50

CARDIOLOGISTS OVER 50

Sarma A, et al JACC 2017;69:92

FAMILY PLANNING CONSIDERATIONS OF CARDIOLOGISTS

PRECONCEPTION

PREGNANCY

EARLY PARENTHOOD

Women are often asked whether they intend to have children during interviews

A career in cardiology often impacts family planning

Female cardiologists avoid pregnancy during periods of radiation exposure

Women underutilize radiation reduction and monitoring strategies

Cardiologist experience a high incidence of pregnancy complications

Pressure to take shorter parental leave

Women do not meet their breastfeeding goals

Avoid such questions

Offer all candidates information on parental leave policies

Recognize the importance of pregnancy, parental leave, and breastfeeding

Include radiation exposure recommendations in fluoroscopy training

Connect cardiologists with radiation safety officer

Provide maternity lead and fetal dosimeters

Parental leave of 2 months for all cardiologists (men and women) with flexibility to account for potential complications

Optimize space, me, and culture acceptance for women to express milk in the workplace

Sarma, A.A. et al. J Am Coll Cardiol. 2017;69(1):92-101.

When asked why cardiologists did not pursue interventional cardiology, women more commonly cited concerns regarding radiation exposure as compared with men (20% vs. 12%; p < 0.001).
When compared with women older than 40 years of age, women < 40 years of age were twice as likely to report radiation exposure as a barrier to choosing interventional cardiology (12% vs. 27%)
Women were relatively uninformed about whether their department had an official policy regarding radiation exposure during pregnancy
- Only, 34% reported that their department did
- 34% reported being unaware if their department had such a policy
- 32% reported that their department did not
There was no difference between those older than 50 years of age versus younger than 50 years of age with respect to knowledge regarding such policies (p = 0.96), potentially limiting senior cardiologists from providing mentorship on this issue to younger colleagues.

Studies have shown a lack of knowledge for radiation safety and lack of routine implementations of radiation protective strategies
WIC Pregnancy Workforce Group suggested all cardiologists receive education regarding pregnancy radiation exposure on entering fellowship, at time of employment, and each time they undergo fluoroscopy credentialing

Y. Morishima, K. Chida, Y. Katahira, et al. Need for radiation safety education for interventional cardiology staff. Acta Cardiol, 71 (2016): 151-155
G. Sadigh, et al. Radiation safety knowledge and perceptions among residents. Acad Radiol, 21 (2014): 869-878

SCAI Consensus Document on Occupational Radiation Exposure to the Pregnant Cardiologist and Technical Personnel
Describes the risk of radiation exposure to pregnant physicians
Educates on radiation monitoring and mechanisms to reduce radiation exposure
Clarifies the data – that to date, there is no data to suggest a significant increased risk to the fetus of pregnant women
Purpose was to also help justify that pregnant physicians should not be precluded from performing procedures in cath lab

Catheterization and Cardiovascular Interventions 77:232–241 (2011)

IR: A Joint Guideline of the Society of Interventional Radiology (SIR) and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE)
Joint guideline from SIR and CIRSE experts in both academic and private sectors of medicine
Acknowledges that pregnant radiation workers may have heightened concern of radiation risk to unborn child
Addresses misinformation surrounding reproductive and developmental risks of radiation exposure and its effect on the conceptus
Emphasizes that understanding of radiation doses and associated risks is necessary for both protection of conceptus as well as preventing potential discrimination and unnecessary constraints on pregnant women

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181

A European Heart Rhythm Association (EHRA) consensus document endorsed by the Heart Rhythm Society (HRS)
The EHRA issued in 2014 a practical guide on ways to reduce radiation dose for patients and staff during electrophysiological procedures.
The purpose of the consensus document as an adjunct to the EHRA practical guide is to describe the current knowledge on the risks and to inform about current international recommendations and legislations on occupational exposure in the electrophysiology laboratory to personnel with childbearing potential and during pregnancy.
The consensus document states that pregnant medical workers may continue to work in a radiation environment if they wish to provided that there is reasonable assurance that the fetal exposure dose can be kept below 1 mSv in the EU and 5 mSv in the USA during the course of pregnancy and requiring the employer to review the exposure conditions of pregnant women carefully*

Heidbuchel H et al. European Heart Rhythm Association. Practical ways to reduce radiation dose for patients and staff during device implantations and electrophysiological procedures. Europace 2014;16:946-64.
Sarcozy A et al. Occupational radiation exposure in the electrophysiology laboratory with a focus on personnel with reproductive potential and during pregnancy: A European Heart Rhythm Association (EHRA) consensus document endorsed by the Heart Rhythm Society (HRS) Europace (2017) 19, 1909-1922. doi:10.1093/europace/eux252

National Council for Radiation Protection (NRCP) and International Commission on Radiological Protection (ICRP)
Recommendations by the NRCP and ICRP for optimizing occupational exposure are controlled by the following:
- Limit on the annual effective dose
- Limit on the annual equivalent dose to specific organs or structures
- Limit of annual equivalent fetal dose over the entire gestation
These recommendation are enforced by regulatory agencies
Europe: limits for occupational exposure are included the European Directive 2013/59/Euratom
In the US, implementation can vary from state to state

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181

NCRP

Monthly equivalent dose limit of 0.5mSv to the embryo/fetus (excluding medical natural background radiation) once pregnancy is declared

NRC (Nuclear Regulatory Commission)

Regulatory limit of 5mSv during the entire pregnancy of the declared pregnant woman

IRCP & European Commission

Equivalent dose to unborn child should be as low as reasonably achievable and not exceed 1mSv during duration of pregnancy

Bhatt, D. et al. Cardiovascular Intervention: A Companion to Braunwald’s Heart Disease; 2015

A statement of the European Association of Percutaneous Cardiovascular Interventions (EAPCI) in collaboration with the European Heart Rhythm Association (EHRA), the European Association of Cardiovascular Imaging (EACVI), the ESC Regulatory Affairs Committee and Women as One.
Highlights that radiation exposure is commonly identified as a major barrier for women considering a career in interventional cardiology and electrophysiology
Reports several European countries where pregnant women are not allowed to work in the cath-lab
Updates biological evidence of radiation exposure during pregnancy
Provides data from the practice showing that the majority of fetal radiation dose exposure rarely exceeds 0.3 mSv
Makes proposals for encouraging gender equity and overcoming the “radiation barrier”

Manzo et al. EuroIntervention 2022;18-online publish-ahead-of-print November 2022

National Council for Radiation Protection (NRCP) and International Commission on Radiological Protection (ICRP)
Recommendations by the NRCP and ICRP for optimizing occupational exposure are controlled by the following:
- Limit on the annual effective dose
- Limit on the annual equivalent dose to specific organs or structures
- Limit of annual equivalent fetal dose over the entire gestation
These recommendation are enforced by regulatory agencies
Europe: limits for occupational exposure are included the European Directive 2013/59/Euratom
In the US, implementation can vary from state to state

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171-181
Sarcozy A. Occupational radiation exposure in the electrophysiology laboratory with a focus on personnel with reproductive potential and during pregnancy: A European Heart Rhythm Association (EHRA) consensus document endorsed by the Heart Rhythm Society (HRS) Europace (2017) 19, 1909-1922. doi:10.1093/europace/eux252

Spontaneous abortion

> 14%

Genetic abnormalities

4-10%

Intrauterine growth retardation

4%

Major congenital malformation

2-4%

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181

FEtal Risk as a Function of Radiation Dose

Fetal risk as a function of radiation dose

Dose to conceptus (mGy) above natural background

Probability of no malformation

Probability of no cancer (0-19 years)

0

97

99.7

1

97

99.7

5

97

99.7

RECALL: US NRC Regulatory equivalent dose limit is 5mSv during the entire pregnancy of the declared pregnant woman

10

97

99.6

50

97

99.4

100

97

99.1

> 100

possible,
see text

higher

There is no evidence that radiation dose to the fetus < 100mGy during pregnancy is associated with an increased incidence of congenital malformation, stillbirth, miscarriage, growth malformation or mental disability

No statistically significant or convincing evidence of an increased risk of cancer in offspring of female radiation workers

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181

2018 Occupational Fetal Dose Averages

FETAL: Cleveland clinic - 2018

Occupational Fetal Dose Average

All X-ray Departments
Cardiac EP Department Only
Maximum Fetal Dose (right Axis)
Regulatory Fetal Dose Limit = 5,000 (uSv)

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181

2018 PHYSICIAN Occupational RADIATION DOSES

Cleveland clinic - 2018

Average Annual EDE
Maximum Annual EDE

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181

NCRP

Monthly equivalent dose limit of 0.5mSv to the embryo/fetus (excluding medical natural background radiation) once pregnancy is declared with a maximum equivalent fetal dose of 5 mSv for the whole pregnancy

NRC (Nuclear Regulatory Commission)

Regulatory limit of 5mSv during the entire pregnancy of the declared pregnant woman

IRCP & European Commission

Equivalent dose to unborn child should be as low as reasonably achievable and not exceed 1mSv during duration of pregnancy

Bhatt, D. et al. Cardiovascular Intervention: A Companion to Braunwald’s Heart Disease; 2015

On December 2013 the EU Council unanimously adopted the ICRP recommendations in the Article 106—Directive 2013/59/Euratom
General instructions in regards to pregnant workers:
- Once the woman has declared pregnancy, the employer must ensure that the fetus equivalent dose remains ≤1 mSv
- Requires for a radiation protection expert to give a competent advice on the matters relating to the compliance with applicable legal requirements, in respect of employment conditions for pregnant and breastfeeding workers.
- EU Member States will have until February 2018 to translate this directive into national legislation
However, there are countries in Europe where pregnant women are forbidden to work in an ionizing environment

European Council. Council Directive 2013/59/Euratom of 5 December 2013 laying down basic safety standards for protection against the dangers
arising from exposure to ionizing radiation, and repealing Directives 89/618/Euratom, 90/641/Euratom, 96/29/Euratom, 97/43/Euratom and
2003/122/Euratom. Official Journal of the European Union 2014;57:1–73.

Current legal requirements for pregnant workers: EU, UK, USA, Australia, Israel

Overview of the current EU regulations and their local application demonstrating a general trend in more restrictive applicative directives usually limiting access to the catheterisation/electrophysiology lab and allowing a discretional power to the X-ray surveillance experts.

Overview of the current non-EU regulation with focus on the EU.

The European Directive 2013/59/Euratom, Art.10 has been adopted in your Country. YES/NO

COUNTRY LAW

Exposure during pregnancy (cumulative dose over the pregnancy)

Exposure during breastfeeding

In-hospital discretionary allowance

AUSTRIA

YES

Not allowed

NA

BELGIUM

YES

ARBIS 20-07-2001

Yes, should be <1 mSv and ALARA

Yes, allowed

Risk analysis of occupational exposure for every pregnant woman with arbitrary allowance according to the X-ray surveillance expert.

CYPRUS

YES

2018

Yes, should be <1 mSv

Yes, allowed

NA

DENMARK

YES

BEK nr 669 af 01/07/2019 (equivalent to EU directive)

Yes, should be <1 mSv after pregnancy is recognised − special dosimetry is encouraged (day-to-day monitoring)

Ok, but exposure should be limited

NA

FRANCE

YES

Articles D. 4152-5 and R. 4451-45 of French Labour Code

Yes, should be <1 mSv

No specific indications

Possibility of shifting the pregnant woman to an occupation with less radiation exposure or keeping her in her current assignment if the total expected radiation dose between pregnancy confirmation and childbirth is <1 mSv

GERMANY

YES

Strahlenschutzgesetz (StrlSchG): German Radiation Protection Law dated June 27, 2017 (Federal Law Gazette Part I, p. 1,966), last amended by Article 2 of the law of May 20, 2021 (Federal Law Gazette Part I p. 1,194): §78Strahlenschutzverordnung (StrlSchV): German Radiation Protection Ordinance dated November 29, 2018 (Federal Law Gazette Part I, p. 2,034-2,036), last amended by Article 6 of the law of May 20, 2021 (Federal Law Gazette Part I p. 1,194): §55

Yes, should be <1 mSv, weekly monitoring

Yes, allowed

Risk analysis of occupational exposure for every pregnant woman with arbitrary allowance according to the X-ray surveillance expert.

Manzo S et al. EuroIntervention 2022;18-online publish-ahead-of-print November 2022

Overview of the current non-EU regulation with focus on the EU.

The European Directive 2013/59/Euratom, Art.10 has been adopted in your Country. YES/NO

COUNTRY LAW

Exposure during pregnancy (cumulative dose over the pregnancy)

Exposure during breastfeeding

In-hospital discretionary allowance

HUNGARY

YES, in a restricted manner (no exposure when pregnant/breastfeeding)

Government Decree 487/2015 (XII. 30.) on the protection against ionising radiation and the corresponding licensing, reporting (notification) and inspection system

Not allowed

The pregnant woman shall have her work reorganised to avoid any risk (including infections, radiation, etc.).The pregnant woman cannot be dismissed/suspended because of her status.

IRELAND

YES

RADIOLOGICAL PROTECTION ACT 1991 (IONISING RADIATION) REGULATIONS 2019

Yes, should be <1 mSv

Yes, allowed

NA

ITALY

YES, in a restricted manner (no exposure when pregnant/breastfeeding)

DL 101 July 2020

Not allowed

NETHERLANDS

YES

Yes, should be <1 mSv

Yes, allowed

Risk analysis of occupational exposure for every pregnant woman with arbitrary allowance according to the X-ray surveillance expert

PORTUGAL

YES (108/2018, article 69) 102/2009

102/2009, 10 September

Not allowed

ROMANIA

YES

LAW 154/2015

Not allowed

The employer must change the working conditions, so that there is no radiation exposure

SLOVENIA

ZVISJV-1, December 2017

Yes, should be <1 mSv, monthly monitoring

Yes, allowed

Institution is obliged to organise a different workplace or reorganise working time under exposure so the goal <1 mSv can be met

SPAIN

YES, current laws, although enacted before this directive was issued, are in accordance with it

Royal Decree 298/2009, of 6th March, which modifies the Royal Decree 39/1997, of 17th January

Yes, should be <1 mSv, monthly monitoring

Yes, allowed. During the breastfeeding period the worker will not be employed in a job with radionuclides and contaminants

Even though current law allows women to work provided the dose is <1 mSv for the whole pregnancy, in some cases, the the X-ray surveillance department or the occupational risk department do not allow a woman to work

SWEDEN

YES

SFS 2018:396

Yes, should be <1 mSv

Yes, allowed

How a foetal dose below 1 mSv is ensured is up to the authority, i.e., the public healthcare provider. There may be different ways of calculating the foetal dose between hospitals. Currently a factor of 5 is used.

Manzo S et al. EuroIntervention 2022;18-online publish-ahead-of-print November 2022

Overview of the current non-EU regulation with focus on the UK, USA, Australia and Israel.

The European Directive 2013/59/Euratom, Art.10 has been adopted in your Country. YES/NO

COUNTRY LAW

Exposure during pregnancy (cumulative dose over the pregnancy)

Exposure during breastfeeding

In-hospital discretionary allowance

AUSTRALIA

NO, the current Australian codes and standards are based on the 2020 guidelines of the International Commission on Ionising Radiation Protection (ICNIRP)

Australian Radiation Protection and Nuclear Safety Agency Radiation Protection Diagnostic and Interventional Cardiology, series 14.1. Australian Radiation Health Committee. 2008

Yes, dose to foetus should be <1 mSv from declaration of pregnancy to delivery

Yes, allowed (no threshold specified)

NA

ISRAEL

NO

1992 Law by the Ministry of Labor, Social Affairs and Social Services

Yes, dose should be <1 mSv/9 months

Yes, allowed. No limitations

At 4 months pregnancy − medical examination by occupational medicine

UK

YES

The Ionising Radiation Regulations 2017 (IRR 17)

1 mSv limit

None for radiation(only radionuclides and contaminants)

1 mSv limit

USA

Pregnancy Discrimination Act and the American Disabilities Act: pregnant workers have a legal right to work adjustments that allow them to do their job without jeopardising their health

Individual states have Pregnant Workers Fairness laws

No legal specifications regarding exposure.NCPR recommends a dose <5 mSv/9 months

No legal specifications regarding exposure

Yes

Manzo S et al. EuroIntervention 2022;18-online publish-ahead-of-print November 2022

Threshold doses and spontaneous risk

Main deterministic/stochastic irradiation effects on the embryo/fetus at each pregnancy stage.

Overview of the current non-EU regulation with focus on the EU.

Pregnancy stage

Main irradiation effect

Doses at which effects have been described

Risk at occupational dose (range ≤1-5 mSv exposure to the mother)

Spontaneous risk24

Preconception gonadal irradiation

Has not been shown to result in increased cancer or malformations in children13

Preimplantation(First two weeks post-conception)

Abortion

Doses over 100 mGy25

Death of the conceptus due to radiation is not described28

Risk of spontaneous abortion in known pregnant women 1/7

Period of major organogenesis(weeks 3-8 post-conception)

Risk of malformation or growth retardation

Dose threshold of around 100 mGy26

Not expected below 100 mGy26

Risk of major congenital malformations 1/33Risk of growth retardation 1/33

Early foetal period (weeks 8-25 post-conception)

Risk of reducing the intelligence quotient

Dose threshold of around 120-200 mGy weeks 8-15Dose threshold of around 500 mGy weeks 16-25

Doses under 100 mGy and in the mother’s occupational exposure range (<5 mSv) would be of no practical significance26

Third trimester

Risk of malformation, growth retardation or reduced intelligence quotient not expectedPossible fatal or non-fatal cancer of any type (solid tumours and leukaemia)

Lifetime cancer risk following in utero exposure will be similar to that following radiation in early childhood

Lifetime cancer risk around 1/500 for 5 mSv in utero exposure2728, and 1/2,500 for 1 mSv in utero exposure2728

Risk of childhood leukaemia per year 1/25,000/year

Sarcozy A et al. Europace (2017) 19, 1909–1922. doi:10.1093/europace/eux252
Manzo S et al. EuroIntervention 2022;18-online publish-ahead-of-print November 2022

Probability of a child to be born with a congenital malformation or to develop childhood cancer spontaneously and after ionizing radiation exposure

Foetal dose added to the background radiation (mSv)

Probability of a child having a congenital malformation (%)2930

Probability of a child developing childhood cancer (%)2931

Probability of a child having a congenital malformation or childhood cancer (%)32

0 (spontaneous risk)

4

0.07

4.07

0.5

4.001

0.074

4.072

1

4.002

0.079

4.078

2.5

4.005

0.092

4.09

5

4.01

0.11

4.12

10

4.02

0.16

4.17

Kneale GW et al. J Natl Cancer Inst. 1976;57:1009-14. 30.
Wagner LK et al. Medical Physics. 1998;25: 1557-8. 31.
Jablon S et al. Lancet. 1970;2:1000-3. 32.
Wagner LK et al. Radiology. 1982; 145:559-62.
Sarcozy A et al. Europace (2017) 19, 1909–1922. doi:10.1093/europace/eux252
Manzo S et al. EuroIntervention 2022;18-online publish-ahead-of-print November 2022

Spontaneous abortion

> 14%

Genetic abnormalities

4-10%

Intrauterine growth retardation

4%

Major congenital malformation

2-4%

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181

FEtal Risk as a Function of Radiation Dose

Fetal risk as a function of radiation dose

Dose to conceptus (mGy) above natural background

Probability of no malformation

Probability of no cancer (0-19 years)

0

97

99.7

1

97

99.7

5

97

99.7

RECALL: US NRC Regulatory equivalent dose limit is 5mSv during the entire pregnancy of the declared pregnant woman

10

97

99.6

50

97

99.4

100

97

99.1

> 100

possible,
see text

higher

There is no evidence that radiation dose to the fetus < 100mGy during pregnancy is associated with an increased incidence of congenital malformation, stillbirth, miscarriage, growth malformation or mental disability

No statistically significant or convincing evidence of an increased risk of cancer in offspring of female radiation workers

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181
Applegate KE. Radiation exposures in pregnancy, health effects and risks to the embryo/foetus—information to inform the medical management of the pregnant patient. J.
Radiol. Prot. 41 (2021) S522–S539 (18pp)

2018 Occupational Fetal Dose Averages

FETAL: Cleveland clinic - 2018

Occupational Fetal Dose Average

All X-ray Departments
Cardiac EP Department Only
Maximum Fetal Dose (right Axis)
Regulatory Fetal Dose Limit = 5,000 (uSv)

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181

Occupational Fetal Dose - Data from the practice

Current published and unpublished data from practice or indirect studies

Author

Settings

Attitude during pregnancy and dose received

Outcome

Spain(Velázquez et al, 201710)

Interventional cardiologists and electrophysiologists (n=5)

Background radiation in 80% of all pregnancies, 0.2 mSv in one pregnancy

4 normal pregnancy outcomes, 1 pregnancy with placental insufficiency

New Zealand* (Unpublished anecdotal accounts only)

Multiple trainees and interventional cardiologists in New Zealand

Unpublished accounts of case-by-case and monthly foetal monitoring with radiation dose well below safe pregnancy thresholds*

Normal pregnancy outcomes reported

Australia* (unpublished anecdotal accounts only)(*Burgess S; on behalf of Women in Interventional Cardiology of Australia and New Zealand (WIICAN). Unpublished data on pregancy in Female Interventional Cardiologists of Australia and New Zealand 2021)"

Multiple trainees and interventional cardiologists in Australia(n=11)

Unpublished accounts of case-by-case and monthly foetal monitoring with radiation dose well below safe pregnancy thresholds In detail: Of 19 female interventional cardiologists (IC) in Australia and New Zealand2, 13/19 (68%) known to the author* were directly contacted by phone or email, 11/13 responded (85%). Amongst responders 11/11 (100%) had at least one pregnancy during advanced training, fellowship or consultancy. A total of 21 pregnancies were included. Amongst responders, during 86% of all pregnancies, doctors, including 82% of IC, remained in the cath lab with appropriate shielding and without any adjustment of schedule or cath lab exclusion. Of the remaining 2 IC, one doctor was excluded from weeks 8-15 in 1 of 2 pregnancies but remained in the lab without exclusion for her other pregnancy, and the remaining doctor chose to self-exclude from the catheterisation laboratory from approximately 6-9 weeks.All 11/11 responders (100%) reported dose monitoring at the time of their pregnancies with radiation doses well below thresholds for safe pregnancy as defined by Australian and New Zealand policy and standards.

Pregnancy outcomes consistent with those of the general population were reported

USA(Marx MV et al 199233)

Prospective study (n=30) of interventional radiologists and trainees (not pregnant, male and female)

The calculated average dose to pregnant interventional radiologists (in 1992) over a 40-week pregnancy with two layers of lead=0.4 mSv dose calculated to be 1.3 mSv with one layer of lead (NCRP occupational foetal dose limit=5 mSv)

France(Vautrin et al34)

Questionnaire among the female population in interventional cardiology in France (n=14)

14/26 women had children. Half of them continued to work during the first trimester of pregnancy, and 2 continued until 7 months. Four wore an additional lead apron for double lead protection of the abdomen. Dose received was not asked in the questionnaire.

Outcomes not reported

USA(Sarma AA et al6)

Survey of the women in cardiology section of the American College of Cardiology (n=501 women)

47% of women tried to avoid pregnancy during periods when they would be exposed to radiation and 57% of women experienced radiation during a pregnancy, without a difference between trainees (49%) vs attending physicians (58%; p=0.28). Those under 50 at the time of the survey were actually more likely to have avoided pregnancy during periods of radiation exposure as compared with those >50 (50% vs 39%; p=0.03), suggesting that younger cardiologists are more concerned about radiation.Women were relatively uninformed about whether their department had an official policy regarding radiation exposure during pregnancy: 34% saying they didn’t know if their department had a policy, 32% reporting that their department did not, and 34% reporting that their department did (no difference between women >50 years of age and women <50 years of age, potentially limiting senior cardiologists from providing mentorship on this issue to younger colleagues).Among women who experienced pregnancy radiation exposure, only 20% used foetal radiation badges, 24% used additional lead, and 42% increased their distance from radiation sources. Thus, despite a high rate of concern, pregnant cardiologists underuse radiation reduction and monitoring strategies.Dose received during pregnancies was not asked in the survey.

Outcomes not reported

Kneale GW et al. J Natl Cancer Inst. 1976;57:1009-14. 30.
Wagner LK et al. Medical Physics. 1998;25: 1557-8. 31.
Jablon S et al. Lancet. 1970;2:1000-3. 32.
Wagner LK et al. Radiology. 1982; 145:559-62.
Sarcozy A et al. Europace (2017) 19, 1909–1922. doi:10.1093/europace/eux252
Manzo S et al. EuroIntervention 2022;18-online publish-ahead-of-print November 2022

Occupational Fetal Dose - Data from the practice

Unpublished data from practice. Available data show that the majority of foetal radiation dose exposure rarely exceeds 0.3 mSv.

Country

Pregnancies with radiation exposure, standard shift

Means of reducing foetal radiation exposure

Equivalent dose received during pregnancy

Outcome

Spain

15 pregnancies/11 interventional cardiologists

Standard 1 vest+1 skirt 7/15Extra skirt or gonadal protection shield 8/15

Background radiation 8/150.2 mSv 2/15<1 mSv 3/15Don’t recall 2/15

14 pregnancies: normal outcome1 pregnancy: placental insufficiency

France

8 pregnancies/5 interventional cardiologists

Standard 1 vest+1 skirt 5/8Extra removable on-wheels shield protection 3/8

7/8 pregnancies: background radiation0.23 mSv in one pregnancy

Normal pregnancy outcomes reported for all pregnancies

Manzo et al. EuroIntervention 2022;18-online publish-ahead-of-print November 2022

2018 PHYSICIAN Occupational RADIATION DOSES

Cleveland clinic - 2018

Average Annual EDE
Maximum Annual EDE

Dauer, L.T et al. J Vasc Interv Radiol 2015; 26:171–181

CIRCLE CHART EXPRESSING DOSE LIMITS

3 mSv:

Annual natural background radiation dose in US

5 mSv:

Legal dose limit for entire gestation

~0.3 mSv:

Under-lead dose to working pregnant interventionalist over entire gestation

~0.09 mSv:

How much fetus of working pregnant interventionalist estimated to receive over entire gestation

100 mSv:

Known threshold for fetal injury

* Please note, legal and natural dose limits are based on US data. Limits vary by country

Ghatan C and Kothary N. Radiation Safety Considerations for the Female Interventionist. Endovascular Today. August 2016

Fetal radiation ≤ 50 mSv (5 rem) is considered negligible
This dose does not affect the outcome of the pregnancy compared to control populations exposed to background radiation estimated as < 1 mGy (0.1 rad) over the gestational period

Brent RL. Clin Perinatol 1986;13:615-48
Catheterization and Cardiovascular Interventions 77:232–241 (2011)

Managing the radiation safety of pregnant stuff. Pregnancy should be declared to physician’s radiation safety officer to ensure protection of fetus and confidential disclosure.

Manzo S et al. EuroIntervention 2022;18-online publish-ahead-of-print November 2022

Dosimeter – wear additional badge under your lead apron at the waist level
- Keep track of multiple sites/locations
Pregnancy should be declared to the radiation safety office to ensure protection of fetus
- Confidential disclosure
US Federal law prohibits against discrimination of pregnant workers
Practice ALARA!
Decrease occupational exposure through radiation protection measures

Brent RL. Clin Perinatol 1986;13:615-48
Catheterization and Cardiovascular Interventions 77:232–241 (2011)

Understand basic radiation physics
Understand lead garments and protective wear
Understand positional orientation of oneself and equipment

PATIENT-CENTERED VIEW

X-RAY SYSTEM

THREE MAJOR COMPONENTS

X-RAY TUBE

PATIENT

DETECTOR ASSEMBLY

Hirshfeld et al. 2018 ACC/HRS/NASCI/SCAI/SCCT Expert Consensus Document on Optimal Use of Ionizing Radiation in CV Imaging.
J Am Coll Cardiol. 2018 Jun 19;71(24):2811-2828.

PROVIDER-CENTERED VIEW

X-RAY SYSTEM

THREE MAJOR COMPONENTS

X-RAY TUBE

PATIENT

DETECTOR ASSEMBLY

QUANTITY

MEDIUM

MEASUREMENT

UNIT

Air Kerma

Air

X-tube output

Milligray (mGy)

Absorbed dose

Tissue

Tissue dose

Milligrays (mGy)

Equivalent dose

Tissue

Absorbed dose x radiation weighting factor

Millisieverts (mSv)

Effective dose

Human

Whole body effective

Millisieverts (mSv)

1 rem = 10 mSv

Y. Morishima, K. Chida, Y. Katahira, et al. Need for radia on safety educa on for interven onal cardiology sta . Acta Cardiol, 71 (2016): 151-155
G. Sadigh, et al. Radia on safety knowledge and percep ons among residents. Acad Radiol, 21 (2014): 869-878

ANNUAL EFFECTIVE DOSE

50mSv/y

CUMULATIVE EFFECTIVE DOSE

10mSv x Age (y)

EQUIVALENT DOSE LIMITS FOR TISSUES AND ORGANS

TOTAL BODY

20 mSv/yr averaged over defined periods of 5 yrs with no individual annual exposure to exceed 50 mSv.

LENS OF THE EYE

100 mSv/5 yrs (20 mSv/yr)

SKIN

500 mSv/yr

HANDS AND FEET

500 mSv/yr

Miller et al. J Am Coll Radiol. 2012 May;9(5):366-8

MODALITY

PROTOCOL

TYPICAL EFFECTIVE DOES (mSv)

Fluoroscopy

TAVR, transapical approach

12-23

Fluoroscopy

TAVR, transfemoral approach

33-100

Fluoroscopy

Diagnostic electrophysiological study

0.1-3.2

Fluoroscopy

Radiofrequency ablation of arrhythmia

1-25

Fluoroscopy

Permanent pacemaker implantation

0.2-8

Fluoroscopy

Diagnostic invasive coronary angiography

2-20

Fluoroscopy

Percutaneous coronary intervention

5-57

Hirshfeld et al. 2018 ACC/HRS/NASCI/SCAI/SCCT Expert Consensus Document on Optimal Use of Ionizing Radiation in CV Imaging.
J Am Coll Cardiol. 2018 Jun 19;71(24):2811-2828.

MODALITY

PROTOCOL

TYPICAL EFFECTIVE DOES (mSv)

MDCT

Coronary CT angiography;
helical, no tube current modulation

8-30

Coronary CT angiography;
helical, tube current modulation

6-20

Coronary CT angiography;
prospectively triggered axial

0.5-7

Coronary CT angiography;
high-pitch helical

<0.5-3

CT angiography, pre-TAVR:
coronary (multiphase) and chest/abdomen/pelvis

5-50

Calcium score

1-5

Attenuation correction

<0.5-2.0

EBCT

Calcium Score

1

SPECT

10 mCi ^99mTc sestamibi rest/
30 mCi ^99mTc sestamibi stress

11

10 mCi ^99mTc sestamibi rest/
30 mCi ^99mTc sestamibi stress

17

30 mCi ^99mTc sestamibi rest/
30 mCi ^99mTc sestamibi stress

18

10 mCi ^99mTc sestamibi stress only

2.7

30 mCi ^99mTc sestamibi stress only

8

Hirshfeld et al. 2018 ACC/HRS/NASCI/SCAI/SCCT Expert Consensus Document on Optimal Use of Ionizing Radiation in CV Imaging.
J Am Coll Cardiol. 2018 Jun 19;71(24):2811-2828.

Time

SPEND LESS TIME ON THE PEDAL

Distance

INCREASE THE DISTANCE FROM X-RAY SOURCE

Shielding

BLOCK SCATTERED RADIATION FROM THE PATIENT

Hirshfeld et al. 2018 ACC/HRS/NASCI/SCAI/SCCT Expert Consensus Document on Optimal Use of Ionizing Radiation in CV Imaging.
J Am Coll Cardiol. 2018 Jun 19;71(24):2811-2828.

INTERVENTIONAL OUTFIT WITH ACCESSORIES

TABLE SET-UP

IMAGE ACQUISITION

BADGE MONITORING

Hirshfeld et al. 2018 ACC/HRS/NASCI/SCAI/SCCT Expert Consensus Document on Optimal Use of Ionizing Radiation in CV Imaging. J Am Coll Cardiol. 2018 Jun 19;71(24):2811-2828.

Leaded glasses

Shoulder Pads

Leaded apron

Radiation badge

Lead thyroid collar

Ring Dosimeter

Leg shields

Personal Rules for
my lead

MAKE SURE YOUR LEAD FITS

INVEST IN YOUR COMFORT

HANG UP YOUR LEAD

DON’T SIT IN YOUR LEAD

0.5-mm thickness attenuates 98- 99.5% of the scatter radiation dose
0.35-mm thickness attenuates approximately 95-96% of the scatter of radiation
Handle lead with care – protection is lost when they crack!
Monitor deterioration and improper storage
Aprons should undergo periodic screening for monitoring of defect

Cathet Cardiovasc Diagn 1992;25(3):186-94.

Historically, women were told to wear “double” lead or 0.5mm lead only throughout the duration of their pregnancy
Data shown thus far confirms that the majority of fetal dose exposure rarely exceeds 0.3mSv

Pregnant Women and Lead Apron Thickness

SPINE PROBLEMS VS INVASIVE YEARS

% in Sample
% with Spine Problems

orthopedic problems AND
total annual case load

Spine Problems
Hip, Knee or
Ankle Problem

Use of 0.75mm lead equivalent glasses can decrease dose by factor of 5-10
Use of scatter-shield can decrease the lens dose by a factor of 5-25
Use of both glasses and scatter-shield can decrease lens dose by factor of 25 or more
Cataract development is a deterministic effect such that there is threshold dose below which it won't develop.
Threshold for radiation induced lens injury (opacities and cataracts) of 1 to 2 Gy for a single acute exposure
The minimum latent period between exposure and diagnosis is ~ 1 year.

Heart 2003;89(10):1123-4.

TABLE POSITION

Drag to move the patient to view the radiation exposure results.

OPTIMAL

TABLE TOO LOW

TABLE TOO LOW / DETECTOR TOO HIGH

Significantly reduces radiation exposure to the operator’s eyes but not the hands
Lead shields ( ~1mm) can attenuate at least 99% of the scatter radiation and in studies reduced overall radiation exposure by 50-75%

Am J Cardiol 2002;89(1):44-49.

0.5mm lead equivalent cap provides additional protection from
LAO projections create high level scatter radiation to operator’s left side
Occupational radiation exposure-induced malignancies with left side involvement have been speculated by a number of observational studies
Anecdotal reports of additional weight causing headaches

DISTANCE FROM THE IMAGE INTENSIFIER

Increasing the working distance from 40 cm to 80cm can decrease scatter radiation to around one fourth of the original dose.
Use additional tubing in radial cases to increase working distance away from radiation sources

Slide courtesy of Dr. Patricia Best

AVOID STEEP ANGULATIONS OF C-ARM

Bhatt, D. et al. Cardiovascular Intervention: A Companion to Braunwald’s Heart Disease; 2015

Views that minimize radiation exposure:
AP views and RAO views should be preferred to the LAO views to reduce radiation dose.
Frame rate:
Halving the frame rate reduces the radiation dose by 50%.
Use collimation:
Active collimation reduces volume irradiate, reducing overall patient dose and scatter radiation.

Br J Radiol 1996;69:860-4.
Slide courtesy of Dr. Patricia Best

1

ALARA

2

Decrease number and length of cine acquisitions and fluoro time

3

“Table UP, I. I. DOWN”Decrease patient to Image intensifier distance + Increase source to image distance

4

Minimize steep C-arm angulation

5

Vary the C-arm angles to avoid repetitive exposure

6

Limit digital magnification (increase skin dose exposure by 50%)

7

Apply Collimation as often as possible

J Am Coll Cardiol Intv 2012;5:866 –73