Cumulative exposure to medical radiation for children requiring surgery for congenital heart disease

Cumulative Radiation Exposure and Lifetime Cancer Risk in Patients With Tetralogy of Fallot Requiring Early Intervention

Background

Neonates with tetralogy of Fallot and symptomatic cyanosis (sTOF) require early intervention, utilizing either a staged repair (SR) or primary repair (PR) approach. They are exposed to several sources of low-dose ionizing radiation, which may contribute to increased cancer risk.

Objectives

The purpose of this study was to compare cumulative radiation exposure and associated lifetime attributable risk (LAR) of cancer between treatment strategies in sTOF.

Methods

Neonates with sTOF who underwent SR or PR from 2012 to 2017 were retrospectively reviewed from the Congenital Cardiac Research Collaborative. Radiation exposure from all radiologic studies prior to 18 months of age was converted to organ-equivalent doses and projected LAR of cancer incidence using the National Cancer Institute dosimetry tools.

Results

There were 242 neonates from 8 centers, including patients with 146 SR and 96 PR. Cumulative total effective dose was significantly higher for SR (median 8.3 mSv, IQR: 3.0-17.4 mSv) than PR (2.1 mSv, IQR: 0.8-8.5 mSv; P < 0.001). Cumulative organ-level doses were significantly higher in SR compared to PR. Regardless of treatment strategy, LARs were higher in females compared to males. Among organs with median exposure >1 mGy in females, the LAR was highest for breast in SR (mean 1.9/1,000 patients). The highest proportion of cancers attributable to radiation exposure was projected for thyroid cancer in females undergoing SR (7.3%).

Conclusions

Cumulative radiation exposure and LARs were higher among those undergoing SR compared to PR. This will be an important factor to consider in determining the preferred neonatal treatment strategy and should substantiate efforts to reduce radiation exposure in this vulnerable population.

Risk of Cancer in Patients with Congenital Heart Disease: A Systematic Review and Meta-Analysis

INTRODUCTION

There has been remarkable progress in both diagnosis and treatment of patients with congenital heart disease (CHD), with an increasing number of survivors. Whether patients with CHD are more likely to develop cancer is still a controversial issue. This study aimed to quantitatively estimate the association between patients with CHD and the risk of developing cancer through meta-analysis.

METHODS

Web of Science, PubMed, and Embase databases were searched from inception to September 2023 to identify potentially relevant case-control studies and cohort studies that reported risk estimates and confidence intervals (CIs). RevMan software was used to analyze the pooled effect size and test for heterogeneity. The random effect and fixed effect models were applied to the study period. Egger's test was performed to examine publication bias.

RESULTS

We analyzed six studies, consisting of 2 case-control studies and 4 cohort studies comprising 276,124 participants. The overall pooled hazard risk for cancer in patients with CHD was 1.71 (95% CI: 1.28-2.28; p < 0.01), with significant heterogeneity (I2 = 97%, p < 0.01). The quantitative analysis of studies indicates that patients with CHD have an increased risk of developing cancer, even after adjusting for chromosomal disorders.

CONCLUSION

Our study highlights the importance of controlling modifiable factors in cancer prevention and emphasizes the need for health education for patients with CHD in primary care. Given the limited number of studies included in this analysis, further research is needed to accurately quantify the cancer risk of exposed versus unexposed CHD.

The burden of radiation exposure in congenital heart disease: the Italian cohort profile and bioresource collection in HARMONIC project

BACKGROUND

The European-funded Health Effects of Cardiac Fluoroscopy and Modern Radiotherapy in Pediatrics (HARMONIC) project aims to improve knowledge on the effects of medical exposure to ionizing radiation (IR) received during childhood. One of its objectives is to build a consolidated European cohort of pediatric patients who have undergone cardiac catheterization (Cath) procedures, with the goal of enhancing the assessment of long-term radiation-associated cancer risk. The purpose of our study is to provide a detailed description of the Italian cohort contributing to the HARMONIC project, including an analysis of cumulative IR exposure, reduction trend over the years and an overview of the prospective collection of biological samples for research in this vulnerable population.

METHODS

In a single-center retrospective cohort study, a total of 584 patients (323 males) with a median age of 6 (2-13) years, referred at the Pediatric Cardiology in Niguarda Hospital from January 2015 to October 2023, were included. Biological specimens from a subset of 60 patients were prospectively collected for biobanking at baseline, immediately post-procedure and after 12 months.

RESULTS

Two hundred fifty-nine (44%) patients were under 1 year old at their first procedure. The median KAP/weight was 0.09 Gy·cm2/kg (IQR: 0.03-0.20), and the median fluoroscopy time was 8.10 min (IQR: 4.00-16.25). KAP/weight ratio showed a positive correlation with the fluoroscopy time (Spearman's rho = 0.679, p < 0.001). Significant dose reduction was observed either after implementation of an upgraded technology system and a radiation training among staff. The Italian cohort includes 1858 different types of specimens for Harmonic biobank, including blood, plasma, serum, clot, cell pellet/lymphocytes, saliva.

CONCLUSIONS

In the Italian Harmonic cohort, radiation dose in cardiac catheterization varies by age and procedure type. An institution's radiological protection strategy has contributed to a reduction in radiation dose over time. Biological samples provide a valuable resource for future research, offering an opportunity to identify potential early biomarkers for health surveillance and personalized risk assessment.

CanCHD Study of Hematopoietic Cancers in Children With and Without Genetic Syndromes

BACKGROUND

Individuals with genetic syndromes can manifest both congenital heart disease (CHD) and cancer attributable to possible common underlying pathways. To date, reliable risk estimates of hematopoietic cancer (HC) among children with CHD based on large population-based data remain scant. This study sought to quantify the risk of HC by the presence of genetic syndrome among children with CHD.

METHODS AND RESULTS

Data sources were the Canadian CHD database, a nationwide database on CHD (1999-2017), and the CCR (Canadian Cancer Registry). Standardized incidence ratios were calculated for comparing HC incidences in children with CHD with the general pediatric population. A modified Kaplan-Meier curve was used to estimate the cumulative incidence of HC with death as a competing risk. A total of 143 794 children (aged 0-17 years) with CHD were followed up from birth to age 18 years for 1 314 603 person-years. Of them, 8.6% had genetic syndromes, and 898 HC cases were observed. Children with known syndromes had a substantially higher risk of incident HC than the general pediatric population (standardized incidence ratio, 13.4 [95% CI, 11.7-15.1]). The cumulative incidence of HC was 2.44% (95% CI, 2.11-2.76) among children with a syndrome and 0.79% (95% CI, 0.72-0.87) among children without a syndrome. Acute myeloid leukemia had a higher cumulative incidence during early childhood than acute lymphoblastic leukemia.

CONCLUSIONS

This is the first large population-based analysis documenting that known genetic syndromes in children with CHD are a significant predictor of HC. The finding could be essential in informing risk-stratified policy recommendations for cancer surveillance in children with CHD.

Biplane 3D overlay guidance for congenital heart disease to assist cardiac catheterization interventions-A pilot study

Cardiac catheterization for congenital heart disease (CHD) performed under fluoroscopic guidance still lacks definition and requires exposure to ionizing radiation and contrast agents, with most patients needing multiple procedures through their lifetime, leading to cumulative radiation risks. While fusion overlay techniques have been employed in the past to aid, these have been limited to a single plane, while interventions are traditionally performed under biplane fluoroscopy. We describe our initial experience performing cardiac catheterizations guided by an enhanced biplane GuideCCI system© (Siemens Healthcare, Germany) augmented by 3D magnetic resonance imaging and computed tomography modeling. Twenty-one children and young adults with CHD undergoing catheterization procedures between October 2019 and May 2021 were chosen based on their degree of complexity of cardiac anatomy. 3D stereolithography models were generated, overlayed, and displayed in real time, alongside angiographs in both planes on the screen during these procedures. We report successful implementation of this novel technology for performance of 26 interventions including stent placements, balloon dilations, vessel occlusion and percutaneous valve and transvenous pacemaker implantation all in patients with various complex cardiac anatomies. A statistically significant reduction in radiation and contrast use was noted for coarctation of the aorta stent angioplasty and transcatheter pulmonary valve replacement when compared with national benchmarks and local institutional metrics (with and without single plane overlay). No complications were encountered with the use of this technology. Use of a tracheal registration technique provided very good correlation in most cases. Operators preferred using biplane augmented catheterization over traditional fluoroscopy in patients with complex cardiac anatomy undergoing interventions.

Local Diagnostic Reference Levels for Pediatric Interventional Cardiology Procedures in Argentina

The aim of this work was to propose a preliminary local diagnostic reference levels (DRL) for pediatric interventional cardiology (PIC) procedures in Argentina, for different ranges of age and weight. This work has been conducted in the framework of the "Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean" (OPRIPALC) program coordinated by the World Health Organization and the Pan American Health Organization in cooperation with the International Atomic Energy Agency to ensuring that radiation exposures of pediatric patients are the minimum necessary during fluoroscopy-guided interventional procedures. The local DRL values presented in this paper by weight group and age group were 7.1 Gy·cm2 (<5 kg), 10.7 Gy·cm2 (5-15 kg), 18.0 Gy·cm2 (15-30 kg), 15.9 Gy·cm2 (30-50 kg), and 28.2 Gy·cm2 (50-80 kg) and 5.3 Gy·cm2 (<1), 11.2 Gy·cm2 (1 to 5<), 19.6 Gy·cm2 (5 to 10<), and 21.4 Gy·cm2 (10 to 16<), respectively. Our dose results are among the values found in other international studies; however, there is great potential for dose optimization.

Lympho-hematopoietic malignancies risk after exposure to low dose ionizing radiation during cardiac catheterization in childhood

Pediatric patients with congenital heart disease (CHD) often undergo low dose ionizing radiation (LDIR) from cardiac catheterization (CC) for the diagnosis and/or treatment of their disease. Although radiation doses from a single CC are usually low, less is known about the long-term radiation associated cancer risks. We aimed to assess the risk of lympho-hematopoietic malignancies in pediatric CHD patients diagnosed or treated with CC. A French cohort of 17,104 children free of cancer who had undergone a first CC from 01/01/2000 to 31/12/2013, before the age of 16 was set up. The follow-up started at the date of the first recorded CC until the exit date, i.e., the date of death, the date of first cancer diagnosis, the date of the 18th birthday, or the 31/12/2015, whichever occurred first. Poisson regression was used to estimate the LDIR associated cancer risk. The median follow-up was 5.9 years, with 110,335 person-years. There were 22,227 CC procedures, yielding an individual active bone marrow (ABM) mean cumulative dose of 3.0 milligray (mGy). Thirty-eight incident lympho-hematopoietic malignancies were observed. When adjusting for attained age, gender and predisposing factors to cancer status, no increased risk was observed for lympho-hematopoietic malignancies RR/mGy = 1.00 (95% CI: 0.88; 1.10). In summary, the risk of lympho-hematopoietic malignancies and lymphoma was not associated to LDIR in pediatric patients with CHD who undergo CC. Further epidemiological studies with greater statistical power are needed to improve the assessment of the dose-risk relationship.

Cumulative Radiation Dose from Medical Imaging in Children with Congenital Heart Disease: A Systematic Review

Children with congenital heart disease are exposed to repeated medical imaging throughout their lifetime. Although the imaging contributes to their care and treatment, exposure to ionising radiation is known to increase one's lifetime attributable risk of malignancy. A systematic search of multiple databases was performed. Inclusion and exclusion criteria were applied to all relevant papers and seven were deemed acceptable for quality assessment and risk of bias assessment. The cumulative effective dose (CED) varied widely across the patient cohorts, ranging from 0.96 mSv to 53.5 mSv. However, it was evident across many of the included studies that a significant number of patients were exposed to a CED >20 mSv, the current annual occupational exposure limit. Many factors affected the dose which patients received, including age and clinical demographics. The imaging modality which contributed the most radiation dose to patients was cardiology interventional procedures. Paediatric patients with congenital heart disease are at an increased risk of receiving an elevated cumulative radiation dose across their lifetime. Further research should focus on identifying risk factors for receiving higher radiation doses, keeping track of doses, and dose optimisation where possible.

Utilising electroanatomic mapping during ablation in patients with CHD to reduce radiation exposure

BACKGROUND

Patients with CHD can be exposed to high levels of cumulative ionising radiation. Utilisation of electroanatomic mapping during catheter ablation leads to reduced radiation exposure in the general population but has not been well studied in patients with CHD. This study evaluated the radiation sparing benefit of using three-dimensional mapping in patients with CHD.

METHODS

Data were retrospectively collected from the Catheter Ablation with Reduction or Elimination of Fluoroscopy multi-institutional registry. Patients with CHD were selected. Those with previous ablations, concurrent diagnostic or interventional catheterisation and unknown arrhythmogenic foci were excluded. The control cohort was matched for operating physician, arrhythmia mechanism, arrhythmia location, weight and age. The procedure time, rate of fluoroscopy use, fluoroscopy time, procedural success, complications, and distribution of procedures per year were compared between the two groups.

RESULTS

Fifty-six patients with congenital heart disease and 56 matched patients without CHD were included. The mean total procedure time was significantly higher in patients with CHD (212.6 versus 169.5 minutes, p = 0.003). Their median total fluoroscopy time was 4.4 minutes (compared to 1.8 minutes), and their rate of fluoroscopy use was 23% (compared to 13%). The acute success and minor complication rates were similar and no major complications occurred.

CONCLUSIONS

With the use of electroanatomic mapping during catheter ablation, fluoroscopy use can be reduced in patients with CHD. The majority of patients with CHD received zero fluoroscopy.

Transseptal puncture during catheter ablation associated with higher radiation exposure

BACKGROUND

Electroanatomic mapping systems are increasingly used during ablations to decrease the need for fluoroscopy and therefore radiation exposure. For left-sided arrhythmias, transseptal puncture is a common procedure performed to gain access to the left side of the heart. We aimed to demonstrate the radiation exposure associated with transseptal puncture.

METHODS

Data were retrospectively collected from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry. Patients with left-sided accessory pathway-mediated tachycardia, with a structurally normal heart, who had a transseptal puncture, and were under 22 years of age were included. Those with previous ablations, concurrent diagnostic or interventional catheterisation, and missing data for fluoroscopy use or procedural outcomes were excluded. Patients with a patent foramen ovale who did not have a transseptal puncture were selected as the control group using the same criteria. Procedural outcomes were compared between the two groups.

RESULTS

There were 284 patients in the transseptal puncture group and 70 in the patent foramen ovale group. The transseptal puncture group had a significantly higher mean procedure time (158.8 versus 131.4 minutes, p = 0.002), rate of fluoroscopy use (38% versus 7%, p < 0.001), and mean fluoroscopy time (2.4 versus 0.6 minutes, p < 0.001). The acute success and complication rates were similar.

CONCLUSIONS

Performing transseptal puncture remains a common reason to utilise fluoroscopy in the era of non-fluoroscopic ablation. Better tools are needed to make non-fluoroscopic transseptal puncture more feasible.

Variation in Advanced Diagnostic Imaging Practice Patterns and Associated Risks Prior to Superior Cavopulmonary Connection: A Multicenter Analysis

Single ventricle patients typically undergo some form of advanced diagnostic imaging prior to superior cavopulmonary connection (SCPC). We sought to evaluate variability of diagnostic practice and associated comprehensive risk. A retrospective evaluation across 4 institutions was performed (1/1/2010-9/30/2016) comparing the primary modalities of cardiac catheterization (CC), cardiac magnetic resonance (CMR), and cardiac computed tomography (CT). Associated risks included anesthesia/sedation, vascular access, total room time, contrast agent usage, radiation exposure, and adverse events (AEs). Of 617 patients undergoing SCPC, 409 (66%) underwent at least one advanced diagnostic imaging study in the 60 days prior to surgery. Seventy-eight of these patients (13%) were analyzed separately because of a concomitant cardiac intervention during CC. Of 331 (54%) with advanced imaging and without catheterization intervention, diagnostic CC was most common (59%), followed by CT (27%) and CMR (14%). Primary modality varied significantly by institution (p < 0.001). Median time between imaging and SCPC was 13 days (IQR 3-33). Anesthesia/sedation varied significantly (p < 0.001). Pre-procedural vascular access did not vary significantly across modalities (p = 0.111); procedural access varied between CMR/CT and CC, in which central access was used in all procedures. Effective radiation dose was significantly higher for CC than CT (p < 0.001). AE rate varied significantly, with 12% CC, 6% CMR, and 1% CT (p = 0.004). There is significant practice variability in the use of advanced diagnostic imaging prior to SCPC, with important differences in associated procedural risk. Future studies to identify differences in diagnostic accuracy and long-term outcomes are warranted to optimize diagnostic protocols.

RADIATION DOSE FOR PATIENTS WITH KAWASAKI DISEASE UNDERGOING FLUOROSCOPICALLY GUIDED CARDIAC CATHETERIZATION

The goal of the present study was to estimate the radiation dose for a group of 45 Kawasaki disease (KD) patients undergoing fluoroscopically guided cardiac catheterization. The sample of procedures corresponds to a single hospital and was collected in 10 years. Anthropometric characteristics and the quantities of air kerma-area product (PKA) among others were recorded for each procedure. Monte Carlo PCXMC 2.0 software was used to estimate organ and effective doses. The PKA value of 7.2 Gy cm2 was proposed as the local Diagnostic Reference Level for KD. For organ absorbed doses, median values for thyroid, heart, lungs, esophagus, skin, active bone and breast were 1.2; 2.2; 4.6; 2.7; 1.1; 1.2 and 2.7 mGy, respectively. For effective dose, the mean value was 2.7 ± 2.5 mSv. This paper presents the first patient dose values for the KD using catheterization techniques, in Latin America and the Caribbean Region.

Pre- and post-operative cardiovascular CT in Stage I single ventricle palliation

OBJECTIVES

The aim of this study is to describe clinical utility of low dose cardiac computed tomography (CT) in the evaluation of single ventricle physiology before and after Stage I palliation.

BACKGROUND

Despite the increased utilization of CT imaging and advancement of CT technology, there are limited studies describing the routine clinical use of cardiac CT and radiation dose parameters in the single ventricle Stage I palliation.

METHODS

This single center, retrospective study included 57 infants with single ventricle physiology who underwent cardiac CT scans between January 1, 2016 and November 30, 2020. Patients' demographic information, diagnosis, indication, total dose length product (DLP), computed tomographic dose index volume (CTDIvol), cardiac CT findings and intraoperative or intraprocedural findings were reviewed. Estimated effective radiation dose was calculated using a previously published conversion rate.

RESULTS

The studies were performed using different generations of CT scanners over the 4 years period: Somatom AS 128, Somatom definition edge, Somatom Force (Siemens Medical Solutions). The studies performed with dual source scanner with prospective gated technique have lower radiation dose exposure with median effective radiation dose of 0.32 mSv.

CONCLUSION

Pre- and post-operative cardiovascular CT in Stage I single ventricle palliation using newer generation scanners with prospective gated technique can be done with minimal radiation exposure and good image quality. Cardiac CT is a powerful imaging modality for better management planning in this group of patients.

Exposure to low-dose ionising radiation from cardiac catheterisation and risk of cancer: the COCCINELLE study cohort profile

PURPOSE

The COCCINELLE study is a nationwide retrospective French cohort set up to evaluate the risk of cancer in patients who undergone cardiac catheterisation (CC) procedures for diagnosis or treatment of congenital heart disease during childhood.

PARTICIPANTS

Children who undergone CC procedures from 1 January 2000 to 31 December 2013, before the age of 16 in one of the 15 paediatric cardiology departments which perform paediatric CC in mainland France were included. The follow-up started at the date of the first recorded CC procedure until the exit date, that is, the date of death, the date of first cancer diagnosis, the date of the 18th birthday or the 31 December 2015, whichever occurred first. The cohort was linked to the National Childhood Cancer Registry to identify patients diagnosed with cancer and with the French National Directory for the Identification of Natural Persons to retrieve the patients' vital status.

FINDINGS TO DATE

A total of 17 104 children were included in the cohort and followed for 110 335 person-years, with 22 227 CC procedures collected. Among the patients, 81.6% received only one procedure. Fifty-nine cancer cases were observed in the cohort. Standardised incidence ratios (SIRs) were increased for all-cancer (SIR=3.8, 95% CI: 2.9 to 4.9), leukaemia (SIR=3.3, 95% CI: 2.0 to 5.4), lymphoma (SIR=14.9, 95% CI: 9.9 to 22.5) and solid cancers excluding central nervous system (CNS) tumours (SIR=3.3, 95% CI: 2.0 to 5.5) compared with the general population.

FUTURE PLANS

Dose reconstruction is currently underway to estimate individual cumulative doses absorbed to relevant organs, including red bone marrow and brain for respectively haematologic disorders and CNS tumours risk estimation. A dose-response analysis will be conducted with consideration to confounding factors such as age at exposure, gender, predisposing factors to cancer and other sources of medical diagnostic low-dose ionising radiation.

Disseminated Aspergillosis Complicated With a Myocardial Abscess in an Immunodeficient Child

Aspergillosis infection is a major complication of acquired immunosuppression, and is associated with poor prognosis in its invasive form. Cardiac dissemination of invasive aspergillosis is a rare and usually fatal consequence of systemic mycosis. We describe a pediatric case of myocardial aspergillosis abscess in a 12-year-old girl diagnosed with multimodality cardiac imaging approach. The patient underwent prolonged antimycotic treatment and bone marrow transplant, which improved her immunity, and, for the first time in the literature, resulted in a favorable outcome.

The Burden of Radiation Exposure During Transcatheter Closure of Atrial Septal Defect

Radiation reduction in the pediatric cardiac catheterization laboratory is well-suited for targeted quality improvement (QI) interventions. Transcatheter atrial septal defect (ASD) closure was chosen for this QI project based on a homogenous procedural population and inter-operator variability in radiation usage, with the aim to reduce radiation exposure during ASD device closure by 50% over 1 year. The aim for this project was defined and a Key Driver Diagram (KDD) was created with three domains for change: modification of procedural practice, reporting and monitoring/feedback, and team engagement. All patients undergoing attempted transcatheter ASD closure were considered for inclusion. The primary outcome, % reduction in median radiation dose (DAP/Kg), was determined through comparison with a historical cohort. Additional radiation metrics, procedural characteristics, and adverse events (AE) were compared to the historical cohort. Radiation exposure (DAP/kg) was reduced by 55% with a median dose reduction from 26 (15, 61) in a historical cohort to 12 (6, 22) in the intervention population (p <0.001). Fluoroscopy time and cine acquisition utilization significantly decreased. Procedure time, procedural success (defined as successful delivery of the device) and AE did not increase in the QI cohort. Successful practice changes included standardized procedural strategies to limit fluoroscopy and cine acquisition, improved fluoroscopic practice, engagement of the multidisciplinary team, and feedback with data reporting by electronic and in-person reminders. In conclusion, application of QI methodologies such as KDD with engagement of a multidisciplinary team can effectively reduce radiation in the pediatric catheterization laboratory.

Multi-institution assessment of the use and risk of cardiovascular computed tomography in pediatric patients with congenital heart disease

BACKGROUND

Cardiac computed tomography (CT) is increasingly used in pediatric patients with congenital heart disease (CHD). Variability of practice and of comprehensive diagnostic risk across institutions is not known.

METHODS

Four centers prospectively enrolled consecutive pediatric CHD patients <18 years of age undergoing cardiac CT from January 6, 2017 to 1/30/2020. Patient characteristics, cardiac CT data and comprehensive diagnostic risk were compared by age and institutions. Risk categories included sedation and anesthesia use, vascular access, contrast exposure, cardiovascular medication, adverse events (AEs), and estimated radiation dose.

RESULTS

Cardiac CT was performed in 1045 pediatric patients at a median (interquartile range, IQR) age of 1.7 years (0.3, 11.0). The most common indications were arterial abnormalities, suspected coronary artery anomalies, functionally single ventricle heart disease, and tetralogy of Fallot/pulmonary atresia. Sedation was used in 8% and anesthesia in 11% of patients. Peripheral vascular access was utilized for 93%. Median contrast volume was 2 ​ml/kg. Beta blockers were administered in 11% of cases and nitroglycerin in 2% of cases. The median (IQR) total procedural dose length product (DLP) was 20 ​mGy∗cm (10, 50). Sedation, vascular access, contrast exposure, use of cardiovascular medications and radiation dose estimates varied significantly by institution and age (p ​< ​0.001). Seven minor adverse events (0.7%) and no major adverse events were reported.

CONCLUSION

Cardiac CT for CHD is safe in pediatric patients when appropriate CT technology and expertise are available. Scans can be acquired at relatively low radiation exposure with few minor adverse events.

Trajectories of care in congenital heart disease - the long arm of disease in the womb

Our understanding of the development of congenital heart disease (CHD) across the lifespan has evolved. These include the evidence for the change in demographics of CHD, the observations that lifelong complications of CHD result in CHD as a lifespan disease, and the concept of long windows of exposure to risk that start in foetal life and magnify the expression of risk in adulthood. These observations set the stage for trajectories as an emerging construct to target health-service interventions. The lifelong cardiovascular and systemic complications of CHD make the long-term care of these patients challenging for cardiologists and internists alike. A life-course approach is thus required to facilitate our understanding of the natural history and to orient our clinical efforts. Three specific examples are illustrated: neurocognition; cancer resulting from exposure to low-dose ionizing radiation; and cardiovascular disease acquired in ageing adults. As patients grow, they do not just want to live longer, they want to live well. With the need to move beyond the mortality outcome, a shift in paradigm is needed. A life-course health development framework is developed for CHD. Trajectories are used as a complex construct to illustrate the patient's healthcare journey. There is a need to define disease trajectories, wellness trajectories and ageing trajectories in this population. Disease trajectories for repaired tetralogy of Fallot, transposition of the great arteries and the Fontan operation are hypothetically constructed. For clinicians, the life-course horizon helps to frame the patient's history and plan for the future. For researchers, life-course epidemiology offers a framework that will help increase the relevance of clinical enquiry and improve study design and analyses. A health-service policy framework is proposed for a growing number of conditions that start in the before birth and extend as long as contemporary survival now permits. Ultimately, the goal is the precision delivery of health services that enables lifelong health management, organization of developmental health services, and integration of vertical and horizontal health-service delivery.

Longitudinal Improvements in Radiation Exposure in Cardiac Catheterization for Congenital Heart Disease

Background:

The C3PO-QI (Congenital Cardiac Catheterization Project on Outcomes – Quality Improvement), a multicenter registry launched in 2015, instituted quality improvement (QI) initiatives to reduce patient radiation exposure. Through regular collaboration, this initiative would allow for harmony among active participants, maximizing efforts and efficiency at achieving radiation best practices. This study sought to report these efforts with a detailed methodology for which institutions can target initiatives, reducing radiation exposure, and increasing patient safety.

Methods:

Data were collected prospectively by 8 C3PO-QI institutions between January 1, 2015 and December 31, 2017. Radiation exposure was measured in dose area product per body weight (dose area product/kg; µGy*m 2 /kg) and reported by expected radiation exposure categories (REC) and institution for 40 published unique procedure types. Targeted interventions addressing selected strategic domains for radiation reduction were implemented in the pediatric catheterization labs of the C3PO-QI institutions.

Results:

The study consisted of 15 257 unique cases. Median exposure (dose area product/kg) was decreased by 30% for all procedures. Dose area product/kg was reduced in all 3 REC, with the greatest improvement observed in REC I (REC I, −37%; REC II, −23%; REC III, −27%). Although the baseline radiation exposures and exact percent decrease varied across all C3PO-QI sites, each institution demonstrated improvements in radiation dose over time. These improvements occurred with the implementation of institution-specific QI interventions accelerated by participation in the C3PO-QI multicenter collaborative.

Conclusions:

Substantial radiation dose reductions can be achieved using targeted QI methodology and interventions. Participation in a multicenter QI collaborative may accelerate improvement across all centers due to enhanced engagement and shared learning between sites.

Moving beyond two-dimensional screens to interactive three-dimensional visualization in congenital heart disease

Beginning with the discovery of X-rays to the development of three-dimensional (3D) imaging, improvements in acquisition, post-processing, and visualization have provided clinicians with detailed information for increasingly accurate medical diagnosis and clinical management. This paper highlights advances in imaging technologies for congenital heart disease (CHD), medical adoption, and future developments required to improve pre-procedural and intra-procedural guidance.

Cardiac catheterization procedures in children with congenital heart disease: Increased chromosomal aberrations in peripheral lymphocytes

Cardiac catheterization procedures are performed on about 20,000 children with congenital heart disease (CHD) annually in China. The procedure, which involves exposure to ionizing radiation, causes DNA damage and may lead to increased cancer risk. We have studied chromosomal aberrations (CA) in peripheral lymphocytes of CHD children. CA frequencies were assessed in an interventional group of 70 children who underwent cardiac catheterization and a control group of 51 children receiving open-heart surgery. Total CA and all chromosome-type aberrations were higher in the exposed children than in the control group. With respect to the type of septal defect, the translocation frequency was higher in patients with ventricular rather than atrial defects. Cardiac catheterization procedures increase CA frequencies and may also increase the risk of cancer.

Recoarctation of the aorta after the Norwood procedure may be treated during the second stage of the surgical palliation

OBJECTIVES

Recoarctation of the aorta (re-CoA) after the Norwood procedure is traditionally treated during catheter-based aortoplasty (CB-A) performed as a separate procedure preceding stage II surgical palliation (S II SP). Our goal was to determine the efficacy of the protocol according to which re-CoA after the Norwood procedure in patients with hypoplastic left heart syndrome is treated during S II SP using hybrid catheter-based aortoplasty.

METHODS

We compared 2 groups of infants who developed re-CoA after the Norwood procedure and were treated at the same institution: In group I (n = 18), CB-A was traditionally performed before S II SP; in group II (n = 15), CB-A was performed during S II SP using a hybrid procedure (catheter access was through an aortic cannula routinely used for cardiopulmonary bypass). The right ventricular fractional area change was analysed.

RESULTS

The CB-A was performed effectively in both groups. S II SP was performed at a younger age in group II (5.4 ± 0.3 vs 6.0 ± 0.4 months; P = 0.003), with lower body weight (5.6 ± 0.5 vs 6.0 ± 0.4; P = 0.03, respectively). The duration of hospital stay did not differ between the groups (10.6 ± 6.2 vs 11.6 ± 6.4 days; P = 0.91). The right ventricular fractional area change measured before S II SP was higher in group I (39.7 ± 4.2% vs 36.8 ± 3.6%, respectively; P = 0.009), but the difference was not seen 1 month after S II SP (41.0 ± 5.6 vs 39.8 ± 4.1; P > 0.05). The total radiation dose was significantly lower in group II.

CONCLUSIONS

re-CoA after the Norwood procedure in patients with hypoplastic left heart syndrome can be treated effectively during S II SP using a hybrid procedure. The strategy allows for reduction of the total radiation dose and of the number of procedures and does not prolong the postoperative course, even in patients with decreased right ventricular systolic function.

Cancer Risk in Congenital Heart Disease-What Is the Evidence?

As life expectancy in patients with congenital heart disease (CHD) has improved, the risk for developing noncardiac morbidities is increasing in adult patients with CHD (ACHD). Among these noncardiac complications, malignancies significantly contribute to the disease burden of ACHD patients. Epidemiologic studies of cancer risk in CHD patients are challenging because they require large numbers of patients, extended follow-up, detailed and validated clinical data, and appropriate reference populations. However, several observational studies suggest that cancer risks are significantly elevated in patients with CHD compared with the general population. CHD and cancer share genetic and environmental risk factors. An association with exposure to low-dose ionizing radiation secondary to medical therapeutic or diagnostic procedures has been reported. Patients with Down syndrome, as well as, to a lesser extent, deletion of 22q11.2 and renin-angiotensin system pathologies, may manifest both CHD and a predisposition to cancer. Such observations suggest that carcinogenesis and CHD may share a common basis in some cases. Finally, specific conditions, such as Fontan circulation and cyanotic CHD, may lead to multisystem consequences and subsequently to cancer. Nonetheless, there is currently no clear consensus regarding appropriate screening for cancer and surveillance modalities in CHD patients. Physicians caring for patients with CHD should be aware of this potential predisposition and meet screening recommendations for the general population fastidiously. An interdisciplinary and global approach is required to bridge the knowledge gap in this field.

Three-dimensional rotational angiography in congenital heart disease: Present status and evolving future

Three-dimensional rotational angiography (3D-RA) enables volumetric imaging through rotation of the C-arm of an angiographic system and real-time 3D reconstruction during cardiac catheterization procedures. In the field of congenital heart disease (CHD), 3D-RA has gained considerable traction, owing to its capability for enhanced visualization of spatial relationships in complex cardiac morphologies and real time image guidance in an intricate interventional environment. This review provides an overview of the current applications, strengths, and limitations of 3D-RA acquisition in the management of CHD and potential future directions. In addition, issues of dosimetry, radiation exposure, and optimization strategies will be reviewed. Further implementation of 3D-RA will be driven by patient benefits relative to existing 3D imaging capabilities and fusion techniques balanced against radiation exposure.

The brain protective effect of dexmedetomidine during surgery for paediatric patients with congenital heart disease

Objective

To study the brain protective effect of dexmedetomidine (DEX) during surgery in paediatric patients with congenital heart disease (CHD).

Methods

This randomized single-blind controlled study enrolled paediatric patients aged 0–3 years with CHD who underwent surgery and randomized them into two groups: one group received DEX and the control group received 0.9% NaCl during anaesthesia. Demographic data, heart rate (HR), mean arterial pressure (MAP) and central venous pressure (CVP) were recorded. Levels of neuron specific enolase (NES) and S-100β protein were determined using enzyme-linked immunosorbent assays.

Results

The study enrolled 80 paediatric patients with CHD. Compared with the control group, HR, MAP and CVP were significantly lower in the DEX group at all time-points except for T0. At all time-points except for T0, the levels of jugular venous oxygen saturation in the DEX group were significantly higher compared with the control group. At all time-points except for T0, the levels of arterial venous difference and cerebral extraction of oxygen were significantly lower in the DEX group compared with the control group. Levels of NES and S-100β protein in the DEX group were significantly lower compared with the control group at all time-points except for T0.

Conclusion

DEX treatment during surgery for CHD improved oxygen metabolism in brain tissues and reduced the levels of NES and S-100β protein.

Organ and effective doses detriment to paediatric patients undergoing multiple interventional cardiology procedures

The aims of the present study were to present the frequency of multiple interventional cardiac procedures for a certain group of patients obtained at one of the largest paediatric hospitals in Chile. In addition it has been analysed cumulative kerma area product (KAP) and cumulative air kerma (CAK), and calculated organ doses for the patient groups undergoing 2, 3 and ≥ 4 procedures, using Monte Carlo software. Effective doses were also estimated for epidemiological purposes and to permit comparison with other imaging procedures. The sample used corresponds to the last 9 years and refers to a total of 1521 paediatric patients and 1824 interventional cardiac procedures. The results for frequency were: 13.7% of patients underwent 2 procedures, 4.1% underwent 3 procedures and 1.4% underwent 4 or more procedures. The median KAP and CAK values measured for the cumulative procedures in these three groups of patients were 3.7, 5.4 and 10.8 Gy·cm² and 59.9, 83.2 and 147.6 mGy, respectively. In terms of the most irradiated organs during interventional cardiac procedures, the highest median values (for the group of ≥4 procedures) were: active bone marrow 5.0 mGy, lungs 23.5 mGy, oesophagus 15.2 mGy, thyroid 7.8 mGy and breast 11.0 mGy. Median dose value to the heart (for the group of ≥4 procedures) was 12.7 mGy. Median values in terms of calculated effective dose for the three patient groups (with 2, 3 and ≥4 procedures) were 3.4, 5.9 and 8.7 mSv, respectively.

Anesthetic considerations for magnetic resonance imaging-guided right-heart catheterization in pediatric patients: A single institution experience

Cardiac catheterization is an integral part of medical management for pediatric patients with congenital heart disease. Owing to age and lack of cooperation in children who need this procedure, general anesthesia is typically required. These patients have increased anesthesia risk secondary to cardiac pathology. Furthermore, multiple catheterization procedures result in exposure to harmful ionizing radiation. Magnetic resonance imaging-guided right-heart catheterization offers decreased radiation exposure and diagnostic imaging benefits over traditional fluoroscopy but potentially increases anesthetic complexity and risk. We describe our early experience with anesthetic techniques and challenges for pediatric magnetic resonance imaging-guided right-heart catheterization.

Transcatheter Pulmonary Valve Replacement in Congenital Heart Disease

Patients with dysfunctional right ventricular outflow tracks comprise a large portion of patients with severe congenital heart disease. Transcatheter pulmonary valve replacement in patients with dysfunctional right ventricular outflow tracks is feasible, safe, and efficacious. This article reviews current transcatheter valve replacement technology for dysfunctional right ventricular outflow tract and pulmonary valvular disease and its applications to patients with congenital heart disease. Discussed are the approach and preprocedural planning, current options, and applications of transcatheter pulmonary valve therapy. Also considered are future directions in this field as the technologies begin to develop further.

Relationship Between Serum B7-H3 Levels and Prognosis of Congenital Heart Disease in Children

The aim of this study was to investigate the role of B7-H3 in prognosis of congenital heart disease (CHD) children patients. A total of 65 CHD patients within age 3-12 years who went to our hospital were included during August 2011 to December 2012. Demographic data including age, sex, weight, clinical basic information such as New York Heart Association (NYHA) class, pathological type were collected. Blood samples were collected and serum levels of B7-H3, C-reactive protein (CRP), N-Terminal Pro-Brain Natriuretic Peptide (NT-pro-BNP), and High-sensitivity Troponin T (hsTnT) were determined by enzyme-linked immunosorbent assay (ELISA). Characteristics including age, gender, weight, pathological type, NYHA class, and serum levels of hsTnT and CRP showed no significant difference between deceased and survival patients. However, serum levels of B7-H3 and NT-pro-BNP were significantly higher in deceased patients compared survival patients. Patients with high expressed B7-H3 had higher risks for total major cardiovascular events (MACE) occurrence compared with the lower group. Among the MACE events, significant difference was observed in rates of death, new onset of arrhythmias, and surgical, but not in NYHA class worsening and percutaneous intervention. Patients with higher levels if B7-H3 had significantly higher risk for mortality in the 5-year follow-up compared with the lower group, logic analysis was also conducted and results showed that B7-H3 might be an independent risk factor for 5-year mortality for CHD patients. B7-H3 was up-regulated in dead CHD patients, and serum levels of B7-H3 were related to long-term MACE and 5-year mortality of CHD patients.

Dramatic Dose Reduction in Three-Dimensional Rotational Angiography After Implementation of a Simple Dose Reduction Protocol

Previously, median effective dose (ED) of 1.6 mSv per three-dimensional rotational angiography (3DRA) has been reported. This study evaluated ED and image quality in 3DRA after implementation of a simple dose reduction protocol in pediatric catheterizations. Simple conversion factors between 3DRA ED and readily available parameters at the cathlab were determined. The dose reduction protocol consisted of frame reduction (60-30 frames/s (f/s)), active collimation of the X-ray beam, usage of a readily available low dosage program, and a pre-3DRA run check. EDs were calculated with Monte Carlo PCXMC 2.0. Three observers blindly assessed 3DRA image quality of the dose reduction and normal-dose cohort. Between October 2014 and October 2015, 84 patients (median age 4.3 years) underwent 100 3DRAs with a median ED of 0.54 mSv (0.12-2.2) using the dose reduction protocol. Median ED in the normal-dose cohort (17 3DRAs) was 1.6 mSv (1.2-4.9). Image quality in the dose reduction cohort remained excellent. Correlations between ED and dose area product (DAP) and ED and skin dose were found with a ρ of 0.82 and 0.83, respectively. ED exposure of the entire catheterization was reduced to 2.64 mSv. Introduction of a simple protocol led to 66% dose reduction in 3DRA and 79% in the entire catheterization. 3DRA image quality in this group remained excellent. In 3DRA ED correlates well with DAP and skin dose, parameters readily available at the cathlab.

Variability in radiation dose and image quality: A comparison across fluoroscopy-system vendors, generations of equipment and institutions

OBJECTIVES

To evaluate differences in radiation dose and image quality across institutions, fluoroscope vendors and generations of fluoroscopes for pediatric cardiac catheterization.

BACKGROUND

Increased recognition of the potentially harmful effects of ionizing radiation has spurred technological advances in fluoroscopes, as well as increased focus on optimizing fluoroscope performance. There is currently little understanding of variability in the dose-image quality relationship across institutions, fluoroscope vendor and/or generation of equipment.

METHODS

We evaluated latest generation fluoroscopes from Phillips, Siemens, GE, and Toshiba, and an older generation Phillips fluoroscope (release date 2003) at three different institutions. Radiation dose was measured using an anthropomorphic dose-assessment phantom with effective dose in mSv estimated from Monte Carlo simulations. Image quality phantom images were scored on a 12-point scale by three blinded reviewers.

RESULTS

Fluoroscope effective doses ranged from 0.04 to 0.14 mSv/1,000 pulses for fluoroscopy with associated composite image quality scores ranging from 8.0 ± 0.6 to 10.4 ± 1.3. For cineangiography, effective doses ranged from 0.17 to 0.57 mSv/1,000 frames with image quality scores ranging from 10.1 ± 0.3 to 11.1 ± 0.3. There was modest correlation between effective dose and image quality (r = 0.67, P = 0.006). The older generation fluoroscope delivered consistently higher doses than the newer generation systems (2.3- to 3.5-fold higher for fluoroscopy; 1.1- to 3.4-fold higher for cineangiography) without appreciable differences in image quality.

CONCLUSION

Technological advances have markedly improved fluoroscope performance. Comparing latest generation systems across vendors and institutions, we found variability in the dose-IQ relationship and speculate that this reflects both equipment and institutional optimization practices.

Reducing radiation exposure by lowering frame rate in children undergoing cardiac catheterization: A quality improvement study

INTRODUCTION

Reduction of radiation dosage in the pediatric cardiac catheterization laboratory (PCL) is important to reduce the risk of its stochastic effect in children with congenital heart disease. Lowering the frame rate would reduce radiation dosage possibly at the expense of image quality, potentially resulting in higher fluoroscopic time and procedural complication rate.

METHODS

The data were retrospectively analyzed in three eras: era 1 (n = 234), cineangiography 30 frames/sec (f/s) and fluoroscopy 15 pulse/sec (p/s); era 2 (n = 381), cineangiography 30 f/s and fluoroscopy 6 p/s; and era 3 (n = 328), cineangiography 15 f/s and fluoroscopy 6 p/s. Also, three operators blinded to the frame rate setting evaluated cineangiography image quality. In this study, the impact of lowering the default frame rates on radiation dosage, fluoroscopic time, contrast volume, diagnostic image quality, and complication rates in the PCL was assessed.

RESULTS

Overall radiation dosage progressively declined during these eras (70.0 vs 64.1 vs 36.6 µGym² /kg, P < .001) without a difference in significant adverse event rates. There was no significant increase in either fluoroscopy time or contrast volume. There was no difference in the diagnostic image quality between cineangiography 30 and 15 f/s. Lowering the default frame/pulse rates of both fluoroscopy and cineangiography significantly decreased the overall radiation dosage in the PCL. Importantly, fluoroscopy time, contrast volume, and complication rates did not increase while maintaining diagnostic image quality.

CONCLUSION

This quality improvement project proved successful in lowering radiation dosage without compromising the efficacy and safety of catheterizations.

2018 ACC/HRS/NASCI/SCAI/SCCT Expert Consensus Document on Optimal Use of Ionizing Radiation in Cardiovascular Imaging-Best Practices for Safety and Effectiveness, Part 1: Radiation Physics and Radiation Biology: A Report of the American College of Cardiology Task Force on Expert Consensus Decision Pathways Developed in Collaboration With Mended Hearts

The stimulus to create this document was the recognition that ionizing radiation-guided cardiovascular procedures are being performed with increasing frequency, leading to greater patient radiation exposure and, potentially, to greater exposure for clinical personnel. Although the clinical benefit of these procedures is substantial, there is concern about the implications of medical radiation exposure. The American College of Cardiology leadership concluded that it is important to provide practitioners with an educational resource that assembles and interprets the current radiation knowledge base relevant to cardiovascular procedures. By applying this knowledge base, cardiovascular practitioners will be able to select procedures optimally, and minimize radiation exposure to patients and to clinical personnel. Optimal Use of Ionizing Radiation in Cardiovascular Imaging: Best Practices for Safety and Effectiveness is a comprehensive overview of ionizing radiation use in cardiovascular procedures and is published online. To provide the most value to our members, we divided the print version of this document into 2 focused parts. Part I: Radiation Physics and Radiation Biology addresses the issue of medical radiation exposure, the basics of radiation physics and dosimetry, and the basics of radiation biology and radiation-induced adverse effects. Part II: Radiological Equipment Operation, Dose-Sparing Methodologies, Patient and Medical Personnel Protection covers the basics of operation and radiation delivery for the 3 cardiovascular imaging modalities (x-ray fluoroscopy, x-ray computed tomography, and nuclear scintigraphy) and will be published in the next issue of the Journal.

Imaging-Associated Radiation Trends in a Puerto Rican Pediatric Surgical Population: Is Over-Radiation an Issue in Our Emergency Departments?

The increased use of CT scans has raised concerns regarding the risks of early radiation exposure in the Puerto Rico pediatric population. Available literature sustains that repeated exposure to imaging-related radiation in the pediatric population is associated with a 3-fold increase in the risk of developing pediatric hematogenous and central nervous system malignancies. It is for this reason that an international effort known as the Image Gently Campaign was created, mostly based on the “As Low As Reasonably Achievable” (ALARA) principle described by the Center for Disease Control. With this in mind, our aim was to identify whether there are any discrepancies in imaging tendencies outside our pediatric academic center in Puerto Rico and to determine whether our patients are at increased risk of over-radiation. There were 181 patients; five were excluded because of incomplete data. Our results show that children with appendicitis who are evaluated at nontertiary centers are more likely to have a CT scan performed (93%, OR: 4.054; 95% confidence interval: 2.6–6.4), as opposed to a nonradiating imaging study. In the Pediatric University Hospital, a CT scan was performed as the initial study in 23 per cent of the patients (OR: 0.09; 95% confidence interval: 0.05–0.18), favoring ultrasound as the diagnostic modality of choice. Our concern is that if this trend does not change, our pediatric population might have an increased risk of developing associated malignancies. We believe a local effort toward educational strategies should be implemented to prevent radiation overexposure in our pediatric patients.

Diagnostic accuracy of low-dose dual-source cardiac computed tomography as compared to surgery in univentricular heart patients

BACKGROUND

To evaluate the ability of low radiation dose dual-source computed tomography (DSCT) to depict the features of morphological univentricular heart and to define accuracy by comparing findings with surgery.

METHODS

Low radiation dose dual-source cardiac computed tomography (CCT) of 33 cases of functional univentricular heart preliminary diagnosis by echocardiography compared with the results of surgery were retrospectively analyzed (aged 1 day to 4 years, median 5 months). The appropriate dose reduction strategies and iterative reconstruction were applied.

RESULTS

Thirty three univentricular heart patients were classified into three types according to Anderson's classification method, including 16 cases (48.5%) univentricular of right ventricular type with rudimentary chamber of left ventricle, 11 cases (33.3%) univentricular of left ventricular type with rudimentary chamber of right ventricle and 6 cases (18.2%) univentricular heart of indeterminate type without rudimentary chamber. The extracardiac malformation such as hypoplastic aortic arch, coronary artery fistula, total anomalous pulmonary venous returns or hypoplastic lung were presented frequently. The overall sensitivity and specification of cardiac CT was 100% compared to the results of surgery. The procedural dose-length product was 18 ± 5 mGy-cm, and unadjusted and adjusted radiation doses were 0.25 and 0.64 mSv, respectively.

CONCLUSION

Cardiac CT can diagnose accurately and be performed with a low radiation exposure in patients with the functional univentricular heart disease. The aorta, pulmonary artery and lung can be evaluated completely and simultaneously as well. Cardiac CT is an effective advanced non-invasive imaging modality to comprehensive evaluation the functional univentricular heart patients, particularly if cardiac MRI poses a high risk or is contraindicated.

Exposure to Low-Dose Ionizing Radiation From Cardiac Procedures and Malignancy Risk in Adults With Congenital Heart Disease

Background:

Adults with congenital heart disease (CHD) are exposed to increasing amounts of low-dose ionizing radiation (LDIR) from cardiac procedures. Cancer prevalence in this population is higher than in the general population. This study estimates the association between LDIR exposure from cardiac procedures and incident cancer in adult patients with CHD.

Methods:

The study population derived from the Quebec Congenital Heart Disease Database. We measured cumulative numbers of LDIR-related cardiac procedures for each patient until 1 year before the time of cancer diagnosis or administrative censoring. To assess the association between LDIR exposure and cancer risk, we conducted a nested case-control study and matched cancer cases with controls on sex, CHD severity, birth year, and age.

Results:

The study included 24 833 adult patients with CHD aged 18 to 64 years from 1995 to 2009. In >250 791 person-years of follow-up, 602 cancer cases were observed (median age, 55.4 years). The cumulative incidence of cancer estimated up to 64 years of age was 15.3% (95% confidence interval [CI], 14.2–16.5). Cases had more LDIR-related cardiac procedures than controls (1410 versus 921 per 1000 adult patients with CHD, P <0.0001). Cumulative LDIR exposure was independently associated with cancer (odds ratio [OR], 1.08 per procedure; 95% CI, 1.04–1.13). Similar results were obtained by using dose estimates for LDIR exposure (OR, 1.10 per 10 mSv; 95% CI, 1.05–1.15) with a possible dose-related response. The effect measure was in the same direction, and the association was persistent for exposure from ≥6 procedures in all sensitivity analyses: after excluding most smoking-related cancer cases (OR, 1.10 per procedure; 95% CI, 1.05–1.16 and OR when exposure from ≥6 procedures, 3.08; 95% CI, 1.77–5.37), and after applying a 3-year lag period (OR, 1.09 per procedure; 95% CI, 1.03–1.14 and OR when exposure from ≥6 procedures: 2.58; 95% CI, 1.43–4.69).

Conclusions:

To our knowledge, this is the first large population-based study to analyze and document the association between LDIR-related cardiac procedures and incident cancer in the population of adults with CHD. Confirmations of these findings by prospective studies are needed to reinforce policy recommendations for radiation surveillance in patients with CHD where no regulation currently exists. Physicians ordering and performing cardiac imaging should ensure that exposure is as low as reasonably achievable without sacrificing quality of care.