Patient-Specific Dose and Radiation Risk Estimation in Pediatric Cardiac Catheterization

Radiation dose and risk in children undergoing cardiac interventions performed using flat detector angiography systems

The purpose of the study was to measure radiation doses and estimate risk from various beam projections in children undergoing cardiac interventions. The dose area product (DAP) was measured for eleven patent ductus arteriosus device closures (PDA), four atrial septal defect device closures (ASD), and three balloon pulmonary valvuloplasty (BPV) interventions performed using a flat detector system. The total mean DAPs for PDA, ASD and BPV were 1.9 Gycm², 9.8 Gycm² and 6.2 Gycm² respectively. The fluoroscopic kerma dose rates increased by 10%, 33% and 92% when changing the projection from posterior-anterior to lateral projection for PDA interventions among infants, <5 yrs and >5 yrs respectively. The effective dose (ED) and organ doses were estimated from DAP using Monte Carlo software. Lungs received the highest organ dose of 7.4 mGy (PDA), 20.7 mGy (ASD) and 17.3 mGy (BPV) compared to other organs. The mean EDs from PDA, ASD and BPV were 2.5 mSv, 6.1 mSv and 4.9 mSv respectively. PDA intervention performed in infants had a radiation risk 66% higher than children aged between 3-10 years. Their lifetime attributable risk as per BEIR VII for cancer incidence was 1 in 907 males and 1 in 1047 females.

Cumulative Effective and Individual Organ Dose Levels in Paediatric Patients Undergoing Multiple Catheterisations for Congenital Heart Disease

This study examines the cumulative radiation dose levels received by a group of children who underwent multiple cardiac catheterisation procedures during the investigation and management of congenital heart disease (CHD). The purpose is to calculate cumulative doses, identify higher dose individuals, outline the inconsistencies with risk assessment and encourage the establishment of dose databases in order to facilitate the longitudinal research necessary to better understand health risks. A retrospective review of patient records for 117 paediatric patients who have undergone two or more cardiac catheterisations for the investigation of CHD was undertaken. This cohort consisted of patients who were catheterised over a period from September 2002 to August 2014. The age distribution was from newborn to 17 y. Archived kerma-area product (PKA) and fluoroscopy time (T) readings were retrieved and analysed. Cumulative effective and individual organ doses were determined. The cumulative PKA levels ranged from 1.8 to 651.2 Gycm2, whilst cumulative effective dose levels varied from 2 to 259 mSv. The cumulative fluoroscopy time was shown to vary from 8.1 to 193.5 min. Median cumulative organ doses ranged from 3 to 94 mGy. Cumulative effective dose levels are highly variable but may exceed 250 mSv. Individual organ and effective dose measurements remain useful for comparison purposes between institutions although current methodologies used for determining lifetime risks are inadequate.

Radiation dose in paediatric cardiac catheterisation: A systematic literature review

OBJECTIVES

It is believed that children are more sensitive to ionising radiation than adults. This work reviewed the reported radiation dose estimates for paediatric cardiac catheterisation. A systematic literature review was performed by searching healthcare databases for studies reporting radiation dose using predetermined key words relating to children having cardiac catheterisation. The quality of publications was assessed using relevant Critical Appraisal Skills Programme questions and their reported radiation exposures were evaluated.

KEY FINDINGS

It is only in recent years that larger cohort observations have been undertaken. Although radiation dose from paediatric cardiac catheterisation has decreased in recent years, the literature indicated that it remains varied and potentially substantial.

CONCLUSION

Standardisation of weight categories and procedure types such as those recommended by the PiDRL project could help compare current and future radiation dose estimates.

Removal of scatter radiation in paediatric cardiac catheterisation: a randomised controlled clinical trial

OBJECTIVE

This study sought to determine if DNA integrity was compromised by ionising radiation from paediatric cardiac catheterisations and if dose optimisation techniques allowed DNA integrity to be maintained.

MATERIALS AND METHODS

Children were imaged using either: (i) an anti-scatter grid (current departmental protocol), (ii) no anti-scatter grid or, (iii) no anti-scatter grid and a 15 cm air-gap between the child and the x-ray detector. Dose area product and image quality were assessed, lifetime attributable cancer risk estimates were calculated and DNA double-strand breakages quantified using the γH2AX assay.

RESULTS

Consent was obtained from 70 parents/guardians/children. Image quality was sufficient for each procedure performed. Removal of the anti-scatter grid resulted in dose reductions of 20% (no anti-scatter grid) and 30% (15 cm air-gap), DNA double-strand break reductions of 30% (no anti-scatter grid) and 20% (15 cm air-gap) and a reduction of radiation-induced cancer mortality risk of up to 45%.

CONCLUSION

Radiation doses received during paediatric cardiac catheterisation procedures resulted in a significant increase in DNA damage while maintaining acceptable image quality and diagnostic efficacy. It is feasible to remove the anti-scatter grid resulting in a reduction in DNA damage to the patient. The γH2AX assay may be used for assessment of dose optimisation strategies in children.

Organ and effective doses from paediatric interventional cardiology procedures in Chile

The aim of this study was to present the results of organ and effective doses for paediatric patients for different types of interventional cardiology procedures for age and weight groups, derived from a patient dosimetry pilot programme carried out in Chile, under the auspices of the International Atomic Energy Agency. Over seven years, a retrospective collection of demographic and patient dose data was obtained: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time, dose-area product (DAP) and cumulative dose at patient entrance reference point. Monte Carlo software was used to calculate organ and effective doses. 1506 procedures were divided into four age and seven weight groups. Organ doses (median values) for diagnostic and therapeutic procedures were: active bone marrow 0.90 and 0.64mGy; heart 1.99 and 1.46mGy; lungs 3.56 and 2.59mGy; thyroid 1.27 and 0.83; and breast (in the case of females) 1.78 and 1.36mGy. The ranges for effective doses (median values) and weight bands were 1.2-3.9mSv for diagnostic procedures and 1.0-2.5mSv for therapeutic procedures. The resulting conversion factors (median values) to estimate effective dose from DAP (in mSv/Gy.cm2) were: 1.70; 0.89; 0.58; and 0.40, for age groups of <1year, 1-<5years, 5-<10years and 10-<16years, respectively. The obtained set of dose values will enable comparisons with other imaging procedures (comparing the same age bands) for justification and optimization purposes.

PATIENT DOSIMETRY DURING INTERVENTIONAL CARDIAC PROCEDURES IN A DEDICATED CATHETERIZATION LABORATORY

Cardiac interventions often result in high radiation dose to patient's skin, so a reliable indicator in terms of a commonly used dose descriptor is required to monitor skin exposures. In the present study, Gafchromic XR-RV3 film was used to measure the peak skin dose (PSD) during 40 coronary angiography (CA) and 50 percutaneous transluminal coronary angioplasty (PTCA) procedures. Corresponding values of kerma-area product (PKA), fluoroscopy time (FT) and reference air-kerma (Ka,r) were recorded and correlated with PSD. Doses to patient's eyes and thyroid were also measured by using thermoluminescent dosimeters (TLDs) during PTCA procedures. The average dose to thyroid was about six times higher than the average dose to eyes. The mean values of PSD, PKA and FT were 1140 mGy, 97 Gy cm2 and 15.7 min for PTCA and 290 mGy, 21.1 Gy cm2 and 2.4 min for CA procedures, respectively. One in seven patients of PTCA procedure received PSD >2 Gy. With respect to FT, PKA may be used as a better predictor of skin exposures because the correlation of PSD with PKA was found better than with FT for both CA and PTCA procedures.

Radiation dose associated with CT-guided drain placement for pediatric patients

BACKGROUND

To date, there are limited radiation dose data on CT-guided procedures in pediatric patients.

OBJECTIVE

Our goal was to quantify the radiation dose associated with pediatric CT-guided drain placement and follow-up drain evaluations in order to estimate effective dose.

MATERIALS AND METHODS

We searched the electronic medical record and picture archiving and communication system (PACS) to identify all pediatric (<18 years old) CT-guided drain placements performed between January 2008 and December 2013 at our institution. We compiled patient data and radiation dose information from CT-guided drain placements as well as pre-procedural diagnostic CTs and post-procedural follow-up fluoroscopic abscess catheter injections (sinograms). Then we converted dose-length product, fluoroscopy time and number of acquisitions to effective doses using Monte Carlo simulations and age-appropriate conversion factors based on annual quality-control testing.

RESULTS

Fifty-two drainages were identified with mean patient age of 11.0 years (5 weeks to 17 years). Most children had diagnoses of appendicitis (n=23) or inflammatory bowel disease (n=11). Forty-seven patients had diagnostic CTs, with a mean effective dose of 7.3 mSv (range 1.1-25.5 mSv). Drains remained in place for an average of 16.9 days (range 0-75 days), with an average of 0.9 (0-5) sinograms per patient in follow-up. The mean effective dose for all drainages and follow-up exams was 5.3 mSv (0.7-17.1) and 62% (32/52) of the children had effective doses less than 5 mSv.

CONCLUSION

The majority of pediatric patients who have undergone CT-guided drain placements at our institution have received total radiation doses on par with diagnostic ranges. This information could be useful when describing the dose of radiation to parents and providers when CT-guided drain placement is necessary.

PEDIATRIC RADIATION DOSE DURING CARDIAC CATHETERIZATION PROCEDURES IN SUDAN

Children are more radio sensitive than adult. This study aims to assess radiation doses and the associated hazards to pediatric during cardiac catheterization procedures. Radiation dose for 112 patients was estimated in the biggest cardiac center in Sudan. The median KAP in Gy cm2, CK in mGy, number of frames and fluoroscopy time in minutes were (4.6, 29.0, 340.4, 13.5) and (6.0, 35.0, 318, 9.8) for the diagnostic and therapeutic cardiac procedures, respectively. The median (KAP in Gy cm2, effective dose in mSv) for different age groups in the intervals of less than 1 year, 1-<5 years, 5-<10 years and 10-15 years old were (2.2, 4.4), (2.5, 5.0), (4.2, 5.1) and (8.5, 4.1) respectively. Including all the procedures using the multiplicative model of ICRP 60, the mean attributable lifetime risk for stochastic effect was 0.08 and 0.05% for girls and boys, respectively. Training is needed to raise staff awareness about radiation protection.

CONTEMPORARY AUSTRALIAN DOSE AREA PRODUCT LEVELS IN THE FLUOROSCOPIC INVESTIGATION OF PAEDIATRIC CONGENITAL HEART DISEASE

This study examines radiation dose levels delivered to children from birth to 15 y of age in the investigation of congenital heart disease (CHD) at a major Sydney children's hospital. The aims are to compare values with those derived from similar studies, to provide a template for more consistent dose reporting, to establish local and national diagnostic reference levels and to contribute to the worldwide paediatric dosimetry database. A retrospective review of 1007 paediatric procedural records was undertaken. The cohort consisted of 795 patients over a period from January 2007 to December 2012 who have undergone cardiac catheterisation for the investigation of CHD. The age range included was from the day of birth to 15 y. Archived dose area product (DAP) and fluoroscopy time (FT) readings were retrieved and analysed. The mean, median, 25th and 75th percentile DAP levels were calculated for six specific age groupings. The 75th percentile DAP values for the specific age categories were as follows: 0-30 d-1.9 Gy cm2, 1-12 months-2.9 Gy cm2, 1-3 y-5.3 Gy cm2, 3-5 y-6.2 Gy cm2, 5-10 y-7.5 Gy cm2 and 10-15 y-17.3 Gy cm2. These levels were found to be lower than the values reported in comparable overseas studies. Individual year-specific levels were determined, and it is proposed that these are more useful than the common grouping method. The age-specific 75th percentile DAP levels outlined in this study can be used as baseline local diagnostic reference levels. The needs for the standardisation of DAP reporting and for a greater range of age-specific diagnostic reference levels have been highlighted. For the first time, Australian dose values for paediatric cardiac catheterisation are presented.

Sodium Tanshinone IIA Sulfonate Prevents Radiation-Induced Toxicity in H9c2 Cardiomyocytes

The present study was designed to elucidate the key parameters associated with X-ray radiation induced oxidative stress and the effects of STS on X-ray-induced toxicity in H9c2 cardiomyocytes. Cytotoxicity of STS and radiation was assessed by MTT. Antioxidant activity was evaluated by SOD and MDA. Apoptosis was measured by the flow cytometry, Hoechst 33258, clonogenic survival assay, and western blot. It was found that the cell viability of H9c2 cells exposed to X-ray radiation was significantly decreased in a dose-dependent manner and was associated with cell cycle arrest at the G0/G1 phase as well as apoptosis. STS treatment significantly reversed the morphological changes, attenuated radiation-induced apoptosis, and improved the antioxidant activity in the H9c2 cells. STS significantly increased the Bcl-2 and Bcl-2/Bax levels and decreased the Bax and caspase-3 levels, compared with the cells treated with radiation alone. STS treatment also resulted in a significant increase in p38-MAPK activation. STS could protect the cells from X-ray-induced cell cycle arrest, oxidative stress, and apoptosis. Therefore, we suggest the STS could be useful for the treatment of radiation-induced cardiovascular injury.

Radiation dose benchmarks in pediatric cardiac catheterization: A prospective multi-center C3PO-QI study

OBJECTIVES

This study sought to update benchmark values to use a quality measure prospectively.

BACKGROUND

Congenital Cardiac Catheterization Outcomes Project - Quality Improvement (C3PO-QI), a multi-center registry, defined initial radiation dose benchmarks retrospectively across common interventional procedures. These data facilitated a dose metric endorsed by the American College of Cardiology in 2014.

METHODS

Data was collected prospectively by 9 C3PO-QI institutions with complete case capture between 1/1/2014 and 6/30/2015. Radiation was measured in total air kerma (mGy), dose area product (DAP) (µGy*M² ), DAP per body weight, and fluoroscopy time (min), and reported by age group as median, 75^th and 95^th %ile for the following six interventional procedures: (1) atrial septal defect closure; (2) aortic valvuloplasty; (3) treatment of coarctation of the aorta; (4) patent ductus arteriosus closure; (5) pulmonary valvuloplasty; and (6) transcatheter pulmonary valve implantation.

RESULTS

The study was comprised of 1,680 unique cases meeting inclusion criteria. Radiation doses were lowest for pulmonary valvuloplasty (age <1 yrs, median mGy: 59, DAP: 249) and highest in transcatheter pulmonary valve implantation (age >15 yrs, median mGy: 1835, DAP: 17990). DAP/kg standardized outcome measures across weights within an age group and procedure type significantly more than DAP alone. Radiation doses decreased for all procedures compared to those reported previously by both median and median weight-based percentile curves. These differences in radiation exposure were observed without changes in median fluoroscopy time.

CONCLUSIONS

This study updates previously established benchmarks to reflect QI efforts over time. These thresholds can be applied for quality measurement and comparison. © 2017 Wiley Periodicals, Inc.

Radiation Exposure by Three-Dimensional Rotational Angiography (3DRA) During Trans-catheter Melody Pulmonary Valve Procedures (TMPV) in a Pediatric Cardiac Catheterization Laboratory

This retrospective study aims to evaluate radiation exposure by three-dimensional rotational angiography (3DRA) during trans-catheter Melody pulmonary valve (TMPV) procedures. 3DRA has been reported to have added value in the management of complex congenital heart disease aiding in the performance of interventional procedures albeit with concerns of higher radiation exposure. We test the hypothesis that 3DRA does not cause additional radiation exposure during TMPV procedures. We analyzed all 81 TMPV procedures performed at St. Louis Children's Hospital, MO, USA, from January 1, 2011 to December 31, 2014. Dose-area product (DAP), DAP indexed to body weight (DAP/BW), fluoroscopy time (FT), and weight-fluoroscopy time product of each procedure were recorded. We reviewed each procedure's images to determine whether additional interventions were performed (e.g., pulmonary artery angioplasty or treatment of conduit pseudo-aneurysm). 3DRA was used in 36 % of the procedures. 3DRA group had a higher number of additional procedures performed. The 3DRA group did not differ from the non-3DRA group in DAP, DAP/BW, and weight-fluoroscopy time product. 3DRA does not cause greater radiation exposure during TMPV procedures.

Patient radiation doses in paediatric interventional cardiology procedures: a review

A large number of investigations into the radiation doses from x-ray guided interventional cardiology procedures in children have been carried out in recent years. A review was conducted of these studies, gathering data on kerma area product (P KA), fluoroscopic screening time (FT), air kerma, and estimates of effective dose and organ doses. The majority of studies focus on P KA and FT with no estimation of dose to the patient. A greater than ten-fold variation in average P KA was found between different studies, even where data were stratified by patient age or weight. Typical values of P KA were 0.6-10 Gy · cm2 (<1 year/10 kg), 1.5-30 Gy · cm2 (1-5 years), 2-40 Gy · cm2 (5-10 years), 5-100 Gy · cm2 (10-16 years) and 10-200 Gy · cm2 (>16 years). P KA was lowest for heart biopsy (0.3-10 Gy · cm2 for all ages combined) and atrial septostomy (0.4-4.0 Gy · cm2), and highest for pulmonary artery angioplasty (1.5-35 Gy · cm2) and right ventricular outflow tract dilatation (139 Gy · cm2). Most estimates of patient dose were in the form of effective dose (typically 3-15 mSv) which is of limited usefulness in individualised risk assessment. Few studies estimated organ doses. Despite advances in radiation protection, recent publications have reported surprisingly large doses, as represented by P KA and air kerma. There is little indication of a fall in these dose indicators over the last 15 years. Nor is there much suggestion of a fall in doses associated with the use of flat panel detectors, as opposed to image intensifiers. An assessment of the impact of radiation dose in the context of overall patient outcome is required.

Diagnosis and follow-up of neonatal tetralogy of Fallot and hemitruncus with discontinuous pulmonary arteries noninvasively using awake ultra low-dose computed tomographic angiography

We present a case of an ex-30 week premature male infant diagnosed postnatally with Tetralogy of Fallot, hemitruncus, and discontinuous pulmonary arteries (PAs) at 6 days of life. The patient was diagnosed by echocardiography, and the diagnosis was confirmed on subsequent dual-energy chest CT angiogram. In our patient, the left PA arose directly from the aorta, whereas the right PA originated normally from the right ventricular outflow tract. At 9 days of life, he underwent successful surgical palliation with placement of a modified Blalock–Taussig (aortopulmonary) shunt from the base of the left subclavian artery to the anomalously connected left PA along with anastomosis together of the right and left branch PAs to establish continuity with the main PA. Such cases have been described and are rare. The specific aim of this case report is to illustrate the added benefit of dual-energy electrocardiographically-triggered computed tomographic angiography (CTA) along with standard echocardiography. In addition, high quality images useful in preoperative planning were obtained noninvasively using an ultra low radiation dose without the need for sedation. The information obtained proved essential for confirmation of the diagnosis, preoperative planning, and post-surgical monitoring of branch PA development.

Direct Effective Dose Calculations in Pediatric Fluoroscopy-Guided Abdominal Interventions with Rando-Alderson Phantoms - Optimization of Preset Parameter Settings

Objective

The aim of the study was to calculate the effective dose during fluoroscopy-guided pediatric interventional procedures of the liver in a phantom model before and after adjustment of preset parameters.

Methods

Organ doses were measured in three anthropomorphic Rando-Alderson phantoms representing children at various age and body weight (newborn 3.5kg, toddler 10kg, child 19kg). Collimation was performed focusing on the upper abdomen representing mock interventional radiology procedures such as percutaneous transhepatic cholangiography and drainage placement (PTCD). Fluoroscopy and digital subtraction angiography (DSA) acquisitions were performed in a posterior-anterior geometry using a state of the art flat-panel detector. Effective dose was directly measured from multiple incorporated thermoluminescent dosimeters (TLDs) using two different parameter settings.

Results

Effective dose values for each pediatric phantom were below 0.1mSv per minute fluoroscopy, and below 1mSv for a 1 minute DSA acquisition with a frame rate of 2 f/s. Lowering the values for the detector entrance dose enabled a reduction of the applied effective dose from 12 to 27% for fluoroscopy and 22 to 63% for DSA acquisitions. Similarly, organ doses of radiosensitive organs could be reduced by over 50%, especially when close to the primary x-ray beam.

Conclusion

Modification of preset parameter settings enabled to decrease the effective dose for pediatric interventional procedures, as determined by effective dose calculations using dedicated pediatric Rando-Alderson phantoms.

Evolution of Clinical and Electrophysiological Data in Children with a Preexcitation Syndrome

BACKGROUND

With ablation, the follow-up of preexcitation syndrome now is difficult to assess. The purpose was to collect data of children with a preexcitation syndrome studied on two separate occasions within a minimal interval of 1 year.

METHODS

This is a retrospective chart review of 47 children initially aged 12 ± 4 years, who underwent two or more invasive electrophysiological studies (EPS) within 1-25 years of one another (6.3 ± 4.8) for occurrence of symptoms or new evaluation.

RESULTS

Among initially symptomatic children (n = 25), four (19%) became asymptomatic and one presented life-threatening arrhythmia. Among asymptomatic children (n = 22), five became symptomatic (22.7%). Anterograde conduction disappeared in seven of 23 children with initially long accessory pathway-effective refractory period, but four of six had still induced atrioventricular reentrant tachycardia (AVRT). AVRT was induced at second EPS in three of 13 asymptomatic preexcitation syndrome with negative initial EPS. There were no spontaneous adverse events in the five children with criteria of malignancy at initial EPS; signs of malignancy disappeared in two. At multivariate analysis, AVRT at initial EPS was the only independent factor of symptomatic AVRT during follow-up. Absence of induced AVRT at initial EPS was the only factor of absence of symptoms and a negative study at the second EPS.

CONCLUSIONS

There were no significant changes of data in children after 6.3 ± 4.8 years of follow-up. Most children with spontaneous/inducible AVRTs at initial EPS had still inducible AVRT at second EPS. Induced AF conducted with high rate has a relatively low prognostic value for the prediction of adverse events.

The Benefit of a General, Systematic Use of Mapping Systems During Electrophysiological Procedures in Children and Teenagers: The Experience of an Adult EP Laboratory

Standard imaging during electrophysiological procedures (EPs) uses fluoroscopy. The aim of this study was to evaluate the feasibility, efficacy, safety and effect of an extended use of non-fluoroscopic mapping systems (NMSs) for imaging during paediatric EPs in an adult EP laboratory focusing on the amount of X-ray exposure. This study is a retrospective analysis that includes consecutive young patients (83 pts, aged between 8 and 18) who underwent EPs from March 2005 to February 2015. We compare the fluoroscopy data of two groups of pts: Group I, pts who underwent EPs from 2005 to 2008 using only fluoroscopy and Group II, pts who underwent EPs from 2008 to 2015 performed also using NMSs. The use of an NMS resulted in reduced fluoroscopy time in Group II {median value 0.1 min (95 % CI [0.00-1.07])} compared to Group I {median value 3.55 min (95 % CI [1.93-7.83]) (MW test, P < 0.05)}. There was a complementary reduction in the total X-ray exposure from 2.53 Gy cm(2) (95 % CI [1.51-4.66]) in Group I to 0.05 Gy cm(2) in Group II (95 % CI [0.00-1.22]) (MW test, P < 0.05). Regarding ablation procedures, the median effective dose decreased from 3.04 mSv (95 % CI [1.22-6.89]) to 0.25 mSv (95 % CI [0.00-0.60]) (MW test, P < 0.05). The use of an NMS dramatically reduces fluoroscopy time and total X-ray exposure during EPs in children and teenagers in an adult EP laboratory. In our experience, this reduction is mainly related to the systematic day-to-day use of NMSs.

Reducing Patient Radiation Dose With Image Noise Reduction Technology in Transcatheter Aortic Valve Procedures

X-ray radiation exposure is of great concern for patients undergoing structural heart interventions. In addition, a larger group of medical staff is required and exposed to radiation compared with percutaneous coronary interventions. This study aimed at quantifying radiation dose reduction with implementation of specific image noise reduction technology (NRT) in transcatheter aortic valve implantation (TAVI) procedures. We retrospectively analyzed 104 consecutive patients with TAVI procedures, 52 patients before and 52 after optimization of x-ray radiation chain, and implementation of NRT. Patients with 1-step TAVI and complex coronary intervention, or complex TAVI procedures, were excluded. Before the procedure, all patients received a multislice computed tomography scan, which was used to size aortic annulus, select the optimal implantation plane, valve type and size, and guide valve implantation using a software tool. Air kerma and kerma-area product were compared in both groups to determine patient radiation dose reduction. Baseline parameters, co-morbidity, or procedural data were comparable between groups. Mean kerma-area product was significantly lower (p <0.001) in the NRT group compared with the standard group (60 ± 39 vs 203 ± 106 Gy × cm(2), p <0.001), which corresponds to a reduction of 70%. Mean air kerma was reduced by 64% (494 ± 360 vs 1,355 ± 657 mGy, p <0.001). In conclusion, using optimized x-ray chain combined with specific image noise reduction technology has the potential to significantly reduce by 2/3 radiation dose in standard TAVI procedures without worsening image quality or prolonging procedure time.

Induced apnea enhances image quality and visualization of cardiopulmonary anatomic during contrastenhanced cardiac computerized tomographic angiography in children

Objective:

The purpose of our study was to determine the effect of induced apnea on quality of cardiopulmonary structures during computerized tomographic (CT) angiography images in children with congenital heart diseases.

Methods:

Pediatric patients with congenital heart defects undergoing cardiac CT angiography at our facility in the past 3 years participated in this study. The earlier patients underwent cardiac CT angiography without induced apnea and while, later, apnea was induced in patients, which was followed by electrocardiogram gated cardiac CT angiography. General anesthesia was induced using sleep dose of intravenous propofol. After the initial check CT, on request by the radiologist, apnea was induced by the anesthesiologist by administering 1 mg/kg of intravenous suxamethonium. Soon after apnea ensued, the contrast was injected, and CT angiogram carried out. CT images in the “apnea group” were compared with those in “nonapnea group.” After the completion of the procedure, the patients were mask ventilated with 100% oxygen till the spontaneous ventilation was restored.

Results:

We studied 46 patients, of whom 36 with apnea and yet another 10 without. The quality of the image, visualization of structures such as cardiac wall, outflow tracts, lung field, aortopulmonary shunts, and coronary arteries were analyzed and subjected to statistical analysis (Mann–Whitney U, Fischer's exact test and Pearson's Chi-square test). In the induced apnea group, overall image quality was considered excellent in 89% (n = 33) of the studies, while in the “no apnea group,” only 30% of studies were excellent. Absent or minimal motion artifacts were seen in a majority of the studies in apnea group (94%). In the nonapnea group, the respiratory and body motion artifacts were severe in 50%, moderate in 30%, and minimal in 20%, but they were significantly lesser in the apnea group. All the studied parameters were statistically significant in the apnea group in contrast to nonapnea group (P < 0.000).

Conclusion:

The image quality of cardiac CT angiography greatly improves, and motion artifact significantly decreases with the use of induced apnea in pediatrics patients being evaluated for congenital heart disease. This technique poses no additional morbidity of significance.

Radiation Reduction Capabilities of a Next-Generation Pediatric Imaging Platform

The aims of this study were to quantify patient radiation exposure for a single interventional procedure during transition from an adult catheterization laboratory to a next-generation imaging system with pediatric settings, and to compare this radiation data to published benchmarks. Radiation exposure occurs with any X-ray-directed pediatric catheterization. Technologies and imaging techniques that limit dose while preserving image quality benefit patient care. Patient radiation dose metrics, air kerma, and dose-area product (DAP) were retrospectively obtained for patients <20 kg who underwent patent ductus arteriosus (PDA) closure on a standard imaging system (Group 1, n = 11) and a next-generation pediatric imaging system (Group 2, n = 10) with air-gap technique. Group 2 radiation dose metrics were then compared to published benchmarks. Patient demographics, procedural technique, PDA dimensions, closure devices, and fluoroscopy time were similar for the two groups. Air kerma and DAP decreased by 65-70% in Group 2 (p values <0.001). The average number of angiograms approached statistical significance (p value = 0.06); therefore, analysis of covariance (ANCOVA) was conducted that confirmed significantly lower dose measures in Group 2. This degree of dose reduction was similar when Group 2 data (Kerma 28 mGy, DAP 199 µGy m(2)) was compared to published benchmarks for PDA closure (Kerma 76 mGy, DAP 500 µGy m(2)). This is the first clinical study documenting the radiation reduction capabilities of a next-generation pediatric imaging platform. The true benefit of this dose reduction will be seen in patients requiring complex and often recurrent catheterizations.

Estimation of Organ and Effective Doses for Neonate and Infant Diagnostic Cardiac Catheterizations

OBJECTIVE

Radiation exposure to neonates and infants during cardiac catheterizations is an important issue. Smaller patient size and higher heart rate in these patients result in a greater need for magnification modes and higher frame rates, all of which contribute to a significant increase in radiation doses. The aims of our study were to evaluate organ and effective doses for neonates and infants during diagnostic cardiac catheterizations on the basis of in-phantom dosimetry and conversion factors from dose-area product (DAP) to the effective dose.

MATERIALS AND METHODS

Organ doses for 0- and 1-year-old children during diagnostic cardiac catheterizations were measured by radiophotoluminescence glass dosimeters implanted in neonate and infant anthropomorphic phantoms. The effective doses were evaluated according to recommendations of the International Commission on Radiologic Protection (ICRP) publication 103.

RESULTS

The mean effective doses evaluated according to ICRP 103 were 7.7 mSv (range, 0.1-18.4 mSv) for a neonate and 7.3 mSv (range, 1.9-18.6 mSv) for an infant. Conversion factors from DAP to the effective dose were 2.2 and 4.0 in posteroanterior and lateral cine angiography, respectively, for a neonate and 1.4 and 2.7 in posteroanterior and lateral cine angiography, respectively, for an infant.

CONCLUSION

The dose data and conversion factors evaluated in this study could be useful for the estimation of radiation exposure in neonates and infants during diagnostic cardiac catheterization.

Dual-source computed tomography for evaluating pulmonary artery in pediatric patients with cyanotic congenital heart disease: Comparison with transthoracic echocardiography

PURPOSE

To evaluate the quantitative accuracy of dual-source computed tomography (DSCT) on measurements of pulmonary artery in pediatric patients with cyanotic congenital heart diseases (CCHDs) when compared with transthoracic echocardiography (TTE).

METHODS

Thirty-five patients (mean age: 27.88 ± 28.27 months) with CCHDs underwent DSCT and TTE for evaluating the diameter of the main pulmonary artery (MPA), right pulmonary artery (RPA), and left pulmonary artery (LPA). Surgical measurements were obtained and served as the reference standard. The agreement was tested by linear regression analysis, Pearson's correlation coefficient, and Bland-Altman analysis. The intra- and extracardiac malformations were also observed.

RESULTS

There was a markedly positive correlation between DSCT and surgical measurements of the MPA, RPA, and LPA (r=0.95-0.97; all p<0.001), although the overestimation of the measurements of MPA, RPA, and LPA (bias 0.15 ± 0.95, 0.31 ± 0.63 and 0.35 ± 0.68 mm, respectively) was observed. However, there was a moderate correlation between TTE and surgical measurements of MPA, RPA, and LPA (r=0.61-0.84; all p<0.001), and the underestimation of the measurements of MPA, RPA, and LPA (bias-1.20 ± 1.69, -1.80 ± 1.77, and -1.50 ± 2.30 mm, respectively) was observed. In addition, DSCT was more efficient in finding associated malformations than TTE (40/40 vs. 33/40).

CONCLUSIONS

As a reliable, noninvasive and radiation-save imaging modality, DSCT can provide more accurate pulmonary artery measurements than TTE in cardiac surgical procedures.

Long-term burden of care and radiation exposure in survivors of esophageal atresia

BACKGROUND

Patients with esophageal atresia with or without tracheoesophageal fistula (EA/TEF) historically have had a high risk of neonatal mortality but the majority of patients are now expected to live into adulthood. However, the long-term burden of care among recent EA/TEF survivors has not been documented.

METHODS

A single-institution retrospective review of newborns with EA/TEF treated from 2001-2005 was conducted, including initial and total hospitalization length of stay, and number of clinic visits and procedures requiring general anesthesia in the first three years of life. Exposure to and number of radiological studies involving ionizing radiation (IR) were recorded.

RESULTS

Seventy-one of 78 (91%) patients survived to discharge and 69 were included for analysis. Mean length of initial hospital stay was 51.3 (range 9-390) days. By age 3 years, patients required 4.5 (mean, range 1-23) procedures performed under general anesthesia, attended 13.5 (mean, range 3-40) outpatient visits and were exposed to 17.4 mSv (mean, range 3.0-59.9) of IR from 40 (mean, range 5-165) radiological studies.

CONCLUSION

Patients with EA/TEF need complex and frequent hospital-based care from infancy to early childhood. Opportunities to critically review clinical services and imaging needs should be explored to improve the experience of patients and their families.

Local patient dose diagnostic reference levels in pediatric interventional cardiology in Chile using age bands and patient weight values

PURPOSE

To present the results of a patient dose evaluation program in pediatric cardiology and propose local diagnostic reference levels (DRLs) for different types of procedure and age range, in addition to suggesting approaches to correlate patient dose values with patient weight. This study was the first conducted in Latin America for pediatric interventional cardiology under the auspices of the International Atomic Energy Agency.

METHODS

Over three years, the following data regarding demographic and patient dose values were collected: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time (FT), and two dosimetric quantities, dose-area product (DAP) and cumulative dose (CD), at the patient entrance reference point. The third quartile values for FT, DAP, CD, number of cine series, and the DAP/body weight ratio were proposed as the set of quantities to use as local DRLs.

RESULTS

Five hundred and seventeen patients were divided into four age groups. Sample sizes by age group were 120 for <1 yr; 213 for 1 to <5 yr; 82 for 5 to <10 yr; and 102 for 10 to <16 yr. The third quartile values obtained for DAP by diagnostic and therapeutic procedures and age range were 1.17 and 1.11 Gy cm2 for <1 yr; 1.74 and 1.90 Gy cm2 for 1 to <5 yr; 2.83 and 3.22 Gy cm2 for 5 to <10 yr; and 7.34 and 8.68 Gy cm2 for 10 to <16 yr, respectively. The third quartile value obtained for the DAP/body weight ratio for the full sample of procedures was 0.17 (Gy cm2/kg) for diagnostic and therapeutic procedures.

CONCLUSIONS

The data presented in this paper are an initial attempt at establishing local DRLs in pediatric interventional cardiology, from a large sample of procedures for the standard age bands used in Europe, complemented with the values of the ratio between DAP and patient weight. This permits a rough estimate of DRLs for different patient weights and the refining of these values for the age bands when there may be large differences in child size. These DRLs were obtained at the largest pediatric hospital in Chile, with an active optimization program, and could be used by other hospitals in the Latin America region to compare their current patient dose values and determine whether corrective action is appropriate.

A review of the safety aspects of radio frequency ablation

In light of recent reports showing high incidence of silent cerebral infarcts and organized atrial arrhythmias following radiofrequency (RF) atrial fibrillation (AF) ablation, a review of its safety aspects is timely. Serious complications do occur during supraventricular tachycardia (SVT) ablations and knowledge of their incidence is important when deciding whether to proceed with ablation. Evidence is emerging for the probable role of prophylactic ischemic scar ablation to prevent VT. This might increase the number of procedures performed. Here we look at the various complications of RF ablation and also the methods to minimize them. Electronic database was searched for relevant articles from 1990 to 2015. With better awareness and technological advancements in RF ablation the incidence of complications has improved considerably. In AF ablation it has decreased from 6% to less than 4% comprising of vascular complications, cardiac tamponade, stroke, phrenic nerve injury, pulmonary vein stenosis, atrio-esophageal fistula (AEF) and death. Safety of SVT ablation has also improved with less than 1% incidence of AV node injury in AVNRT ablation. In VT ablation the incidence of major complications was 5-11%, up to 3.4%, up to 1.8% and 4.1-8.8% in patients with structural heart disease, without structural heart disease, prophylactic ablations and epicardial ablations respectively. Vascular and pericardial complications dominated endocardial and epicardial VT ablations respectively. Up to 3% mortality and similar rates of tamponade were reported in endocardial VT ablation. Recent reports about the high incidence of asymptomatic cerebral embolism during AF ablation are concerning, warranting more research into its etiology and prevention.

Transcatheter closure of ruptured sinus of Valsalva aneurysm in a pregnant woman

Sinus of Valsalva aneurysm (SVA) is a rare cardiac anomaly that is usually congenital, but may be acquired. They are usually asymptomatic unless they compress adjacent structures, develop thrombosis, or rupture. A ruptured SVA (RSVA) can lead to rapid hemodynamic deterioration and often needs to be addressed emergently. Surgical correction has traditionally been the treatment of choice for RSVA; however, lately they have been successfully closed percutaneously using various transcatheter devices. Few cases of RSVA during pregnancy have been reported which were conservatively or surgically managed. There is no documented case of transcatheter closure of RSVA during pregnancy. We report the first case of successful percutaneous device closure of RSVA using an Amplatzer duct occluder in a pregnant woman presenting with heart failure due to RSVA at 26 weeks of gestation. <Learning objective: Ruptured sinus of Valsalva aneurysm (RSVA) is traditionally repaired by surgery but more recently amenable to percutaneous intervention. Management of RSVA during pregnancy is complex and has been managed by surgery in the past incurring significant risk to fetus due to effects of cardiopulmonary bypass. We report a case of RSVA in pregnancy that was closed by transcatheter closure for the first time, thereby significantly reducing maternal and fetal risks. While risks are present during pregnancy, emergently indicated life-saving invasive cardiac procedures should not be denied solely on the pregnant state.>.

Total anomalous pulmonary venous connection in a neonate characterised by low-dose, high-pitch cardiac CT

We describe the use of low-dose dual-source cardiac for the evaluation of a neonate with suspected total anomalous pulmonary venous connection. This novel technique obviates the need for sedation or breathholding. Radiation dose-reduction strategies result in sub-mSv-estimated effective doses, substantially lower than annual background radiation dose. Low-dose, high-pitch cardiac CT should be considered as an alternative to MRI or diagnostic cardiac catheterisation in neonates with complex CHD, requiring definitive anatomic evaluation.

Indications for cardiovascular magnetic resonance in children with congenital and acquired heart disease: an expert consensus paper of the Imaging Working Group of the AEPC and the Cardiovascular Magnetic Resonance Section of the EACVI

This article provides expert opinion on the use of cardiovascular magnetic resonance (CMR) in young patients with congenital heart disease (CHD) and in specific clinical situations. As peculiar challenges apply to imaging children, paediatric aspects are repeatedly discussed. The first section of the paper addresses settings and techniques, including the basic sequences used in paediatric CMR, safety, and sedation. In the second section, the indication, application, and clinical relevance of CMR in the most frequent CHD are discussed in detail. In the current era of multimodality imaging, the strengths of CMR are compared with other imaging modalities. At the end of each chapter, a brief summary with expert consensus key points is provided. The recommendations provided are strongly clinically oriented. The paper addresses not only imagers performing CMR, but also clinical cardiologists who want to know which information can be obtained by CMR and how to integrate it in clinical decision-making.

The lateral plane delivers higher dose than the frontal plane in biplane cardiac catheterization systems

The objective of the study is to compare radiation dose between the frontal and lateral planes in a biplane cardiac catheterization laboratory. Tube angulation progressively increases patient and operator radiation dose in single-plane cardiac catheterization laboratories. This retrospective study captured biplane radiation dose in a pediatric cardiac catheterization laboratory between April 2010 and January 2014. Raw and time-indexed fluoroscopic, cineangiographic and total (fluoroscopic + cineangiographic) air kerma (AK, mGy) and kerma area product (PKA, µGym(2)/Kg) for each plane were compared. Data for 716 patients were analyzed: 408 (56.98 %) were male, the median age was 4.86 years, and the median weight was 17.35 kg. Although median beam-on time (minutes) was 4.2 times greater in the frontal plane, there was no difference in raw median total PKA between the two planes. However, when indexed to beam-on time, the lateral plane had a higher median-indexed fluoroscopic (0.75 vs. 1.70), cineangiographic (16.03 vs. 24.92), and total (1.43 vs. 5.15) PKA (p < 0.0001). The median time-indexed total PKA in the lateral plane is 3.6 times the frontal plane. This is the first report showing that the lateral plane delivers a higher dose than the frontal plane per unit time. Operators should consciously reduce the lateral plane beam-on time and incorporate this practice in radiation reduction protocols.

Radiation dose benchmarks during cardiac catheterization for congenital heart disease in the United States

OBJECTIVES

The aim of this study was to define age-stratified, procedure-specific benchmark radiation dose levels during interventional catheterization for congenital heart disease.

BACKGROUND

There is a paucity of published literature with regard to radiation dose levels during catheterization for congenital heart disease. Obtaining benchmark radiation data is essential for assessing the impact of quality improvement initiatives for radiation safety.

METHODS

Data were obtained retrospectively from 7 laboratories participating in the Congenital Cardiac Catheterization Project on Outcomes collaborative. Total air kerma, dose area product, and total fluoroscopy time were obtained for the following procedures: 1) patent ductus arteriosus closure; 2) atrial septal defect closure; 3) pulmonary valvuloplasty; 4) aortic valvuloplasty; 5) treatment of coarctation of aorta; and 6) transcatheter pulmonary valve placement.

RESULTS

Between January 2009 and July 2013, 2,713 cases were identified. Radiation dose benchmarks are presented including median, 75th percentile, and 95th percentile. Radiation doses varied widely between age groups and procedure types. Radiation exposure was lowest in patent ductus arteriosus closure and highest in transcatheter pulmonary valve placement. Total fluoroscopy time was a poor marker of radiation exposure and did not correlate well with total air kerma and dose area product.

CONCLUSIONS

This study presents age-stratified radiation dose values for 6 common congenital heart interventional catheterization procedures. Fluoroscopy time alone is not an adequate measure for monitoring radiation exposure. These values will be used as baseline for measuring the effectiveness of future quality improvement activities by the Congenital Cardiac Catheterization Project on Outcomes collaborative.

Cardiovascular magnetic resonance catheterization derived pulmonary vascular resistance and medium-term outcomes in congenital heart disease

BACKGROUND

Selection of patients with congenital heart disease for surgical septation in biventricular repair or surgical palliation in functionally single ventricles requires low pulmonary vascular resistance (PVR). Where there is uncertainty, PVR can be assessed using hybrid cardiovascular magnetic resonance (CMR) and fluoroscopic (X-Ray) guided cardiac catheterizations (XMR). CMR/XMR catheterization is a validated technique for accurate assessment of pulmonary vascular resistance. However, data concerning its application in clinical practice is lacking.

METHODS

PVR assessments were performed in 167 studies in 149 congenital heart disease patients by CMR/XMR catheterization. Data was collated on patient demographics, procedural data, complications and outcomes. Institutional ethics approval was obtained.

RESULTS

Median age was 3.6 years (6 days-67 years) and weight 13.8 kg (2.3-122 kg). One hundred and eight studies were in biventricular circulations and 59 in functionally single ventricles. Median radiation dose was 0.72 mSv. A baseline Qp:Qs ≤2.75 in biventricular circulations with left-to-right shunts predicted a PVR ≥6 WU x m(2) with 100% sensitivity and 48% specificity. Median follow up until death or last review was 4.2 years (4 days-11 years). Eighty-four patients had a surgical or catheter intervention based on CMR/XMR catheterization findings at a median of 94 days after the study. This included successful biventricular repair at resting PVR values ≤6 WU x m(2) and Fontan completion at  ≤4 WU x m(2).

CONCLUSION

PVR measured by CMR/XMR catheterization allows accurate stratification for intervention in patients with congenital heart disease in both, biventricular and univentricular circulations.

A comparison of radiation dose between standard and 3D angiography in congenital heart disease

Background

The use of three-dimensional rotational angiography (3D-RA) to assess patients with congenital heart diseases appears to be a promising technique despite the scarce literature available.

Objectives

The objective of this study was to describe our initial experience with 3D-RA and to compare its radiation dose to that of standard two-dimensional angiography (2D-SA).

Methods

Between September 2011 and April 2012, 18 patients underwent simultaneous 3D-RA and 2D-SA during diagnostic cardiac catheterization. Radiation dose was assessed using the dose-area-product (DAP).

Results

The median patient age and weight were 12.5 years and 47.5 Kg, respectively. The median DAP of each 3D-RA acquisition was 1093µGy.m² and 190µGy.m² for each 2D-SA acquisition (p<0.01). In patients weighing more than 45Kg (n=7), this difference was attenuated but still significant (1525 µGy.m² vs.413µGy.m², p=0.01). No difference was found between one 3D-RA and three 2D-SA (1525µGy.m² vs.1238 µGy.m², p = 0.575) in this population. This difference was significantly higher in patients weighing less than 45Kg (n=9) (713µGy.m² vs.81µGy.m², P = 0.008), even when comparing one 3D-RA with three 2D-SA (242µGy.m², respectively, p<0.008). 3D-RA was extremely useful for the assessment of conduits of univentricular hearts, tortuous branches of the pulmonary artery, and aorta relative to 2D-SA acquisitions.

Conclusions

The radiation dose of 3D-RA used in our institution was higher than those previously reported in the literature and this difference was more evident in children. This type of assessment is of paramount importance when starting to perform 3D-RA.

Radiation doses from fluoroscopically guided cardiac catheterization procedures in children and young adults in the United Kingdom: a multicentre study

OBJECTIVE

To gather data on radiation doses from fluoroscopically guided cardiac catheterization procedures in patients aged under 22 years at multiple centres and over a prolonged period in the UK. To evaluate and explain variation in doses. To estimate patient-specific organ doses and allow for possible future epidemiological analysis of associated cancer risks.

METHODS

Patient-specific data including kerma area product and screening times from 10,257 procedures carried out on 7726 patients at 3 UK hospitals from 1994 until 2013 were collected. Organ doses were estimated from these data using a dedicated dosimetry system based on Monte Carlo computer simulations.

RESULTS

Radiation doses from these procedures have fallen significantly over the past two decades. The organs receiving the highest doses per procedure were the lungs (median across whole cohort, 20.5 mSv), heart (19.7 mSv) and breasts (13.1 mSv). Median cumulative doses, taking into account multiple procedures, were 23.2, 22.2 and 16.7 mSv for these organs, respectively. Bone marrow doses were relatively low (median per procedure, 3.2 mSv; cumulative, 3.6 mSv).

CONCLUSION

Most modern cardiac catheterizations in children are moderately low-dose procedures. Technological advances appear to be the single most important factor in the fall in doses. Patients undergoing heart transplants undergo the most procedures. An epidemiological assessment of cancer risks following these procedures may be possible, especially using older data when doses were higher.

ADVANCES IN KNOWLEDGE

This is the first large-scale, patient-specific assessment of organ doses from these procedures in a young population.

Novel X-ray imaging technology enables significant patient dose reduction in interventional cardiology while maintaining diagnostic image quality

Objectives

The purpose of this study was to quantify the reduction in patient radiation dose during coronary angiography (CA) by a new X‐ray technology, and to assess its impact on diagnostic image quality.

Background

Recently, a novel X‐ray imaging technology has become available for interventional cardiology, using advanced image processing and an optimized acquisition chain for radiation dose reduction.

Methods

70 adult patients were randomly assigned to a reference X‐ray system or the novel X‐ray system. Patient demographics were registered and exposure parameters were recorded for each radiation event. Clinical image quality was assessed for both patient groups.

Results

With the same angiographic technique and a comparable patient population, the new imaging technology was associated with a 75% reduction in total kerma‐area product (KAP) value (decrease from 47 Gycm² to 12 Gycm², P < 0.001). Clinical image quality showed an equivalent detail and contrast for both imaging systems. On the other hand, the subjective appreciation of noise was more apparent in images of the new image processing system, acquired at lower doses, compared to the reference system. However, the higher noise content did not affect the overall image quality score, which was adequate for diagnosis in both systems.

Conclusions

For the first time, we present a new X‐ray imaging technology, combining advanced noise reduction algorithms and an optimized acquisition chain, which reduces patient radiation dose in CA drastically (75%), while maintaining diagnostic image quality. Use of this technology may further improve the radiation safety of cardiac angiography and interventions. © 2015 Wiley Periodicals, Inc.

ECG-synchronized CT angiography in 324 consecutive pediatric patients: spectrum of indications and trends in radiation dose

The aim of the study is to describe the spectrum of indications for pediatric ECG-synchronized CT angiography (CTA), the main determinants of radiation exposure, and trends in radiation dose over time at a single, tertiary referral center. The study was IRB approved and HIPAA compliant with informed consent waived. Between 2005 and 2013, 324 pediatric patients underwent ECG-synchronized CTA to evaluate known or suspected cardiovascular abnormalities (109 female, median age 8.1 years). The effective dose (ED) was calculated using age-specific correction factors. Univariate and multivariate regression analyses were performed to identify predictors of radiation dose. The most common primary indications for the CTA examinations included known or suspected coronary pathologies (n = 166), complex congenital heart disease (n = 73), and aortic pathologies (n = 41). Median radiation exposure decreased from 12 mSv for patients examined in the years 2005-2007 to 1.2 mSv for patients examined in the years 2011-2013 (p < 0.001). Patients scanned using a tube potential of 80 kV (n = 259) had a significantly lower median radiation dose (1.4 mSv) compared to patients who were scanned at 100 kV (n = 46, median 6.3 mSv) or 120 kV (n = 19, median 19 mSv, p < 0.001). Tube voltage, followed by tube current and the method of ECG-synchronization were the strongest independent predictors of radiation dose. Growing experience with dose-saving techniques and CTA protocols tailored to the pediatric population have led to a tenfold reduction in radiation dose over recent years and now allow routinely performing ECG-synchronized CTA in children with a radiation dose on the order of 1 mSv.

Patient doses in paediatric interventional cardiology: impact of 3D rotational angiography

The aim of this study was to calculate the contribution of 3D rotational angiography to radiation doses received by paediatric patients in a cardiac catheterisation laboratory. The percentage increase in the median value of air kerma-area product due to cone beam CT was 33 and 16% for diagnostic and therapeutic procedures, respectively. Results are presented separately for five age groups and ten weight groups. Several methods for reducing radiation from 3D rotational angiography are suggested and patient doses are compared with previously published values.

Indications for cardiovascular magnetic resonance in children with congenital and acquired heart disease: an expert consensus paper of the Imaging Working Group of the AEPC and the Cardiovascular Magnetic Resonance Section of the EACVI

This article provides expert opinion on the use of cardiovascular magnetic resonance (CMR) in young patients with congenital heart disease (CHD) and in specific clinical situations. As peculiar challenges apply to imaging children, paediatric aspects are repeatedly discussed. The first section of the paper addresses settings and techniques, including the basic sequences used in paediatric CMR, safety, and sedation. In the second section, the indication, application, and clinical relevance of CMR in the most frequent CHD are discussed in detail. In the current era of multimodality imaging, the strengths of CMR are compared with other imaging modalities. At the end of each chapter, a brief summary with expert consensus key points is provided. The recommendations provided are strongly clinically oriented. The paper addresses not only imagers performing CMR, but also clinical cardiologists who want to know which information can be obtained by CMR and how to integrate it in clinical decision-making.

Anesthesia and the pediatric cardiac catheterization suite: a review

Advances in technology over the last couple of decades have caused a shift in pediatric cardiac catheterization from a primary focus on diagnostics to innovative therapeutic interventions. These improvements allow patients a wider range of nonsurgical options for treatment of congenital heart disease. However, these therapeutic modalities can entail higher risk in an already complex patient population, compounded by the added challenges inherent to the environment of the cardiac catheterization suite. Anesthesiologists caring for children with congenital heart disease must understand not only the pathophysiology of the disease but also the effects the anesthetics and interventions have on the patient in order to provide a safe perioperative course. It is the aim of this article to review the latest catheterization modalities offered to patients with congenital heart disease, describe the unique challenges presented in the cardiac catheterization suite, list the most common complications encountered during catheterization and finally, to review the literature regarding different anesthetic drugs used in the catheterization lab.

Cumulative radiation exposure in pediatric patients with congenital heart disease

Certain pediatric patients undergoing surgery for the most severe forms of congenital heart disease are exposed to high doses of ionizing radiation. The amount of cumulative radiation exposure from all modalities has not yet been evaluated. The purpose of our study was to evaluate the cumulative radiation exposure in a contemporary cohort of patients with congenital heart disease undergoing single-ventricle palliation. This is a single-center, retrospective study of pediatric patients undergoing Fontan completion between May 2005 and May 2010. Radiation exposure from all procedures including cardiac catheterizations, computed tomography (CT) scans, plain film radiography, and nuclear medicine scans was evaluated. Radiation dose was calculated as the dose area product (μGy m(2)) and was measured in all cardiac catheterizations, CT scans, and other imaging modalities. Seventy patients who underwent Fontan completion at a mean age of 3.6 ± 1.5 years (range 1.4-8 years) were included in the study. Mean number of chest X-rays was 32 ± 8 (range 10-285) with a mean cumulative total exposure of 1,320 μGy m(2) (range 480-12,960) per patient. Mean number of cardiac catheterizations was 2.45 ± 1.3 (range 1-8), and mean fluoroscopy and cine angiography exposures per case were 1,103 ± 245 and 1,412 ± 273 μGy m(2) giving a mean cumulative exposure of 9,054 μGy m(2) (range 2,515-201,200) per patient for all catheterizations. Mean number of CT scans performed was 0.44 ± 0.4 (0-11), and the mean exposure was 352 μGy m(2), giving a mean cumulative total of 154 μGy m(2) (range 0-3,872) per person. A total of five lung perfusion scans were carried out. Radiation exposure in patients with congenital heart disease undergoing single-ventricle palliation is quite variable. Most of the exposure to ionizing radiation occurs during cardiac catheterization. Strategies to utilize other imaging modalities such as MRI would decrease exposure in this particular group of patients who may be particularly vulnerable to its side effects.