New approaches to reduce radiation exposure

Zero-fluoro atrioventricular-nodal reentrant tachycardia ablation

BACKGROUND

Atrioventricular-nodal reentrant tachycardia (AVNRT) is a common supraventricular tachycardia, particularly in younger patients. The treatment of choice is radiofrequency catheter ablation (RFCA), traditionally necessitating ionizing radiation for catheter guidance.

OBJECTIVE

The authors aimed to demonstrate the feasibility and safety of zero-fluoroscopy RFCA of AVNRT using EnSite™ NavX™ as a three-dimensional (3D) electroanatomical mapping system (EAM).

METHODS

The authors retrospectively analyzed 68 patients that underwent AVNRT-RFCA. One group was a priori allocated to conventional fluoroscopy mapping (convFluoro, n = 30). In 38 cases, the electrophysiologist chose to use 3D-EAM for ablation. Of these patients, 20 could be ablated without fluoroscopy use (zeroFluoro). In 18 cases that were initially intended as 3D-EAM, additional fluoroscopy use was necessary due to difficult anatomic conditions (convertedFluoro). Procedure duration, fluoroscopy duration and dose, as well as complications were analyzed.

RESULTS

Procedure duration was similar for the convFluoro and zeroFluoro groups (74 ± 24 min vs. 80 ± 26 min, p = ns). The convertedFluoro group showed longer procedure duration compared to the convFluoro group (94 ± 30 min vs. 74 ± 24 min, p < 0.05). The use of 3D-EAM significantly reduced fluoroscopy duration comparing the convFluoro with the convertedFluoro group (12 ± 9 min vs. 7 ± 6 min, p < 0.05). The difference in fluoroscopy dose between convFluoro and convertedFluoro did not reach significance (169 ± 166 cGycm2 vs. 134 ± 137 cGycm2, p = ns). In zeroFluoro cases, no radiation was used at all. 3D-EAM-guided RFCA was primarily successful in all patients. Overall, there were only few minor complications in the different groups. No major complications occurred.

CONCLUSION

Zero-fluoro RFCA in patients with AVNRT is feasible and safe. 3D-EAM can reduce radiation exposure in the majority of patients without prolonging procedure duration or increasing complications.

Radioprotective effect of Ginkgolide B on brain: the mediating role of DCC/MST1 signaling

PURPOSE

The risk of brain exposure to ionizing radiation increases gradually due to the extensive application of nuclear technology in medical, industrial, and aerospace fields. Radiation-induced brain injury (RBI) is highly likely to cause a wide range of neurological complications, including schizophrenia, Alzheimer's disease (AD), depression. Ginkgolide B (GB) is one of the effective active components extracted from ginkgo biloba leaves, exerts protective effects on CNS, which is involved in the regulation of the Hippo signaling pathway. MST1, as one of the core kinases of the Hippo pathway, participated in regulating cell proliferation, differentiation, and apoptosis. However, it remains unclear whether GB attenuates radiation brain injury (RBI) and whether the radioprotective effect of GB refers to MST1 signaling. Hence, our study aimed to explore the radiation protection effect and the potential mechanism of GB.

MATERIALS AND METHODS

C57BL/6 mice were stimulated with an X-ray (20 Gy) to establish an RBI model. Then, morris water maze test (MWM) and step-down passive avoidance test (SDPAT) were used to assess the learning and memory function of mice. The open field test (OFT), tail suspension test (TST), and forced swimming test (FST) were used to assess changes in locomotor activity and hopelessness. Besides, X-ray-stimulated SH-SY5Y cells were used to verify the radioprotective effect of GB. Immunofluorescence double staining, Dihydroethidium (DHE), western blot, and flow cytometry were used to explore the role of DCC/MST1 signaling in RBI.

RESULTS

In this study, X-ray-treated mice exhibited cognitive impairment and depression-like behavior, which was ameliorated by GB treatment. GB also reduced the ROS production and the number of TUNEL-positive cells in the hippocampus. Moreover, GB increased the protein levels of p-AKT and Bcl2, while decreased the protein levels of MST1, p-p38, p-JNK, cleaved-caspase-3 and Bax both in vivo and in vitro. Additionally, exogenous Netrin-1 alleviated X-ray-induced ROS production and apoptosis, whereas knockout of Netrin-1 receptor DCC abolished the protective effect of GB.

CONCLUSION

Oxidative stress and MST1-mediated neuronal apoptosis participated in radiation-induced cognitive impairment and depression-like behaviors, and modulation of DCC by GB was an effective intervention against RBI.

Role of Machine Learning-Based CT Body Composition in Risk Prediction and Prognostication: Current State and Future Directions

CT body composition analysis has been shown to play an important role in predicting health and has the potential to improve patient outcomes if implemented clinically. Recent advances in artificial intelligence and machine learning have led to high speed and accuracy for extracting body composition metrics from CT scans. These may inform preoperative interventions and guide treatment planning. This review aims to discuss the clinical applications of CT body composition in clinical practice, as it moves towards widespread clinical implementation.

Identification of a potential diagnostic signature for postmenopausal osteoporosis via transcriptome analysis

Purpose: We aimed to establish the transcriptome diagnostic signature of postmenopausal osteoporosis (PMOP) to identify diagnostic biomarkers and score patient risk to prevent and treat PMOP.

Methods: Peripheral blood mononuclear cell (PBMC) expression data from PMOP patients were retrieved from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were screened using the “limma” package. The “WGCNA” package was used for a weighted gene co-expression network analysis to identify the gene modules associated with bone mineral density (BMD). Least absolute shrinkage and selection operator (LASSO) regression was used to construct a diagnostic signature, and its predictive ability was verified in the discovery cohort. The diagnostic values of potential biomarkers were evaluated by receiver operating characteristic curve (ROC) and coefficient analysis. Network pharmacology was used to predict the candidate therapeutic molecules. PBMCs from 14 postmenopausal women with normal BMD and 14 with low BMD were collected, and RNA was extracted for RT-qPCR validation.

Results: We screened 2420 differentially expressed genes (DEGs) from the pilot cohort, and WGCNA showed that the blue module was most closely related to BMD. Based on the genes in the blue module, we constructed a diagnostic signature with 15 genes, and its ability to predict the risk of osteoporosis was verified in the discovery cohort. RT-qPCR verified the expression of potential biomarkers and showed a strong correlation with BMD. The functional annotation results of the DEGs showed that the diagnostic signature might affect the occurrence and development of PMOP through multiple biological pathways. In addition, 5 candidate molecules related to diagnostic signatures were screened out.

Conclusion: Our diagnostic signature can effectively predict the risk of PMOP, with potential application for clinical decisions and drug candidate selection.

First clinical experience using a visualized sheath for atrial fibrillation ablation

INTRODUCTION

Recently, a novel steerable sheath allowing its real-time visualization within a 3D-mapping system was introduced to facilitate atrial fibrillation (AF) ablation.

AIM

This study aimed to assess safety and efficacy of AF ablation using the visualized sheath and to compare its performance with a matched control group of patients who received ablation with conventional and non-visualized sheaths.

METHODS

The study included consecutive patients between 09/2019 and 02/2021 who underwent routine AF ablation using the visualized sheath. Patients were regularly followed-up in our outpatient's clinic. Arrhythmia recurrence was defined as any atrial fibrillation (AF)/ atrial tachycardia (AT) episode lasting > 30 s after a blanking period of 3 months.

RESULTS

A total number of 100 patients undergoing ablation using the visualized sheath were compared to a group of 99 matched patients. No major complications were observed. Total procedure duration (108 ± 22 min vs. 112 ± 12 min; p = 0.045), fluoroscopy time (7 ± 3 min vs. 10 ± 5 min; p < 0.001) and -dose (507 ± 501 cGy*cm² vs. 783 ± 433 cGy*cm² ; p < 0.001) were significantly lower using the visualized sheath. The benefit in terms of procedure duration was mainly driven by a shortened left atrial dwell time (73 ± 13 min vs. 79 ± 12 min; p = 0.001). During a mean follow-up of 12 months, the overall procedural success was 85% in the visualized sheath group versus 83% in the control group (p = 0.948).

CONCLUSION

AF ablation using the novel visualized sheath is safe and effective and leads to a measurable decrease of procedure duration and radiation exposure. The integration of the novel sheath might help to further improve safety and efficacy of AF ablation.

Occupational Radiation Exposure Among General Surgery Residents: Should We Be Concerned?

BACKGROUND

Low-dose ionizing radiation exposure is associated with development of solid organ tumors as well as increased risk of cataract formation in a linear-dose response. While occupational radiation exposure has been studied across subspecialties with regular fluoroscopy exposure such as interventional radiology and urology, the contribution of increasing endovascular case volume to occupational radiation exposure among general surgery residents remains largely unreported. In this study, we sought to determine typical occupational radiation exposure among a pool of general surgery residents as part of a formal radiation safety curriculum.

METHODS

A radiation safety program was introduced to a group of 28 general surgery residents who rotate on a vascular surgery service with a high endovascular volume in a hybrid room setting. All residents received training in proper use of a radiation dosimeter and minimizing exposure during fluoroscopy times in the operating room. Data was collected from radiation film dosimetry badges distributed to general surgery residents on a bimonthly basis throughout the year, and radiation exposure in mRem was compared between residents rotating on vascular and nonvascular surgical services during 4-week rotations.

RESULTS

A total of 14 months of data were collected. Resident compliance was 84% with regular use and return of dosimeters at the end of each bimonthly cycle. The radiation exposure among residents rotating on vascular surgery was significantly higher compared to those on nonvascular rotations (mean = 71 mRem vs 3.13 mRem, p = 0.02). Exposure among senior residents was not statistically different than that of attending vascular surgeons (mean = 212 mRem vs 164 mRem, p = 0.20). All exposures were significantly lower than institutional ALARA dose limits for radiation exposure (5000 mRem/year).

CONCLUSION

General surgery residents are routinely exposed to measurable occupational radiation levels, especially while participating in endovascular procedures during their training. However, data from our study suggests that these levels are below ALARA dose limits and senior surgical residents are not at greater risk than vascular surgery attending surgeons while on their vascular rotation. The results of this study will be used to help guide resident education on radiation safety and identify institution-specific practices which can minimize exposure and improve radiation safety adherence.

Analysis of causes of death in patients with implanted defibrillators

AIMS

Implantable cardioverter defibrillators (ICDs) are used for primary or secondary prevention of sudden cardiac death. We sought to clarify prognosis and causes of death after ICD implantation.

METHODS AND RESULTS

A total of 2743 patients with ICDs implanted during 1990-2020 were analyzed. Median age was 68.5 (59.6-74.6) years; 21% women, median left ventricular ejection fraction (LVEF) was 30 (23-35), 52% had an ischemic etiology and 77% had a primary preventive indication. Mortality rate after 10 years was 22, 44, 55, and 72% in the 1st, 2nd, 3rd, and 4^th age quartile, respectively. The calculated median sex and age adjusted loss of life years compared to the average German population was 9.7 (6.1-14.0) years. Prognosis was independently related to sex, age, LVEF, and glomerular filtration rate. 713 out of 852 deaths could be classified to a specific cause. Congestive heart failure (CHF) accounted for death in 214 (30%) and sudden death (SD) for 144 patients (20%). Postmortem interrogation of devices in 74 patients revealed VT/VF in 39 and no episodes in 35 patients. Cancer was identified as the cause of death in 121 patients (17% of cases), of which 36 were bronchial carcinomas. 73 (10%) of patients died due to infection. 67 patients (9%) died within 24 h of procedures. Compared to other causes, significantly more life years were lost associated with procedures and SD: 9.3 (5.7-12.9) versus 12.1 (7.4-15.2) and 11.9 (7.6-17.8) years.

CONCLUSION

Life expectancy of ICD patients is lower than for the general population. Mortality is predominantly due to CHF, but there is still a considerable rate of SD. The occurrence of cancers, most importantly bronchial carcinomas, and infections, warrants protective measures. Some deaths during procedures are possibly preventable. Patients with ICDs comprise a vulnerable cohort, and treatment has to be optimized in many directions to improve prognosis.

Zero-fluoroscopy catheter ablation for atrial fibrillation: a transitional period experience

BACKGROUND

Radiofrequency catheter ablation for atrial fibrillation (AF) without using fluoroscopy has been getting popular. In this study, we reported the transition period experience of the zero-fluoroscopy procedure by an experienced operator and shared our zero-fluoroscopy protocol.

METHOD

A total of consecutive 30 AF ablation cases attempted to be treated without fluoroscopy were investigated. Ten serial cases were grouped as fluoroscopy-guided period, and period 1-3 in chronological order. All zero-fluoroscopy attempted cases were assisted with an intracardiac echocardiography device with a three-dimensional electroanatomical system.

RESULTS

Complete zero-fluoroscopy procedure was achieved at the 6th case during the transitional period. During the first period, the total procedure time slightly increased in, but afterward, procedure time was continuously decreased, and it became significantly shorter in the third period than the previous fluoroscopy-guided period. Any additional use of fluoroscopy during the transitional period was mainly for transseptal puncture and diagnostic catheter placement into the coronary sinus. Pulmonary vein isolation was achieved in all patients, and there was one case of hemodynamically insignificant moderate amount pericardial effusion.

CONCLUSION

For an experienced operator, complete zero-fluoroscopy AF ablation might be achieved safely and feasibly within 5-10 cases. Fluoroscopy equipment backup might be useful during the learning period for beginners in the zero-fluoroscopy procedure.

The hidden risk of ionizing radiation in the operating room: a survey among 258 orthopaedic surgeons in Brazil

Background

This study aims to assess orthopaedic surgeon knowledge in Brazil about ionizing radiation and its health implications on surgical teams and patients.

Methods

A 15-question survey on theoretical and practical concepts of ionizing radiation was administered during the 23rd Brazilian Orthopaedic Trauma Association annual meeting. The survey addressed issues within orthopedic surgery, such as radiation safety concepts, protection, exposure, as well as the participant gender. Participants were either orthopedic surgeons or orthopedic surgery residents working at institutions in Brazil.

Results

One thousand surveys were distributed at the moment of the meeting registration, and 258 were answered completely (25.8% response rate). Only 5.8% of participants used basic radiation protection equipment; 47.3% used a dosimeter; 2.7% reached the annual maximum permissible radiation dose; 10.5% knew the period of increased risk to fetal gestation; 5.8% knew the maximum permissible radiation dose during pregnancy; 58.5% knew that the hands, eyes, and thyroid are the most exposed areas and at greater risk of radiation-related lesions; 25.2% knew the safe distance from a radiation-emitting tube is 3 m or more; 44.2% knew the safest positioning of the radiation-emitting tube; 25.2% knew that smaller tubes emit greater radiation at the entrance dose to magnify the image; and 55.4% knew that the surgery team receives more scattered radiation in surgical procedures performed on obese patients.

Conclusion

This study revealed inadequate theoretical and practical knowledge about radiation exposure among orthopaedic surgeons in Brazil. Only a minority of orthopaedic surgeons used basic radiation protection equipment. No significant differences in knowledge were found when comparing all orthopedic surgery specialties. Our findings indicate an urgent need for education to increase knowledge among orthopaedic surgeons about the hazards of ionizing radiation. Personal protection and implementation of the ALARA (as low as reasonably achievable) protocol in daily practice are important behaviors to prevent the harmful effects of ionizing radiation.

Zero-fluoroscopy approach for ablation of supraventricular tachycardia using the Ensite NavX system: a multicenter experience

BACKGROUND

Three-dimensional electroanatomic mapping systems have demonstrated a significant reduction in radiation exposure during radiofrequency catheter ablation procedures. We aimed to investigate the safety, feasibility and efficacy of a completely zero-fluoroscopy approach for catheter ablation of supraventricular tachycardia using the Ensite NavX navigation system compared with a conventional fluoroscopy approach.

METHODS

A multicenter prospective non-randomized registry study was performed in seven centers from January 2013 to February 2018. Consecutive patients referred for catheter ablation of supraventricular tachycardia were assigned either to a completely zero-fluoroscopic approach (ZF) or conventional fluoroscopy approach (CF) according to the operator's preference. Patients with atrial tachycardia were excluded.

RESULTS

Totally, 1020 patients were enrolled in ZF group; 2040 patients ablated by CF approach were selected for controls. There was no significant difference between the zero-fluoroscopy group and conventional fluoroscopy group as to procedure time (60.3 ± 20.3 vs. 59.7 ± 22.6 min, P = 0.90), immediate success rate of procedure (98.8% vs. 99.2%, P = 0.22), arrhythmia recurrence (0.4% vs. 0.5%, P = 0.85), total success rate of procedure (98.4% vs. 98.8%, P = 0.39) or complications (1.1% vs. 1.5%, P = 0.41). Compared with the conventional fluoroscopy approach, the zero-fluoroscopy approach provided similar outcomes without compromising the safety or efficacy of the procedure.

CONCLUSION

The completely zero-fluoroscopy approach demonstrated safety and efficacy comparable to a conventional fluoroscopy approach for catheter ablation of supraventricular tachycardia, and mitigated radiation exposure to both patients and operators.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT03042078; first registered February 3, 2017; retrospectively registered.

Follow-Up Recommendations after Curative Resection of Well-Differentiated Neuroendocrine Tumours: Review of Current Evidence and Clinical Practice

The incidence of neuroendocrine neoplasms (NENs) is increasing, especially for patients with early stages and grade 1 tumours. Current evidence also shows increased prevalence, probably reflecting earlier stage diagnosis and improvement of treatment options. Definition of adequate postsurgical follow-up for NENs is a current challenge. There are limited guidelines, and heterogeneity in adherence to those available is notable. Unfortunately, the population of patients at greatest risk of recurrence has not been defined clearly. Some studies support that for patients with pancreatic neuroendocrine tumours (PanNETs), factors such as primary tumour (T), stage, grade (Ki-67), tumour size, and lymph node metastases (N) are of relevance. For bronchial neuroendocrine tumours (LungNETs) and small intestinal neuroendocrine tumours (siNETs), similar factors have been identified. This review summarises the evidence supporting the rationale behind follow-up after curative resection in well-differentiated PanNETs, siNETs, and LungNETS. Published evidence informing relapse rate, disease-free survival, and relapse patterns are discussed, together with an overview of current guidelines informing postsurgical investigations and duration of follow-up.

Reducing radiation dose in paediatric interventional cardiac catheterisation

OBJECTIVE

Radiation exposure during paediatric cardiac catheterisation procedures should be minimised to "as low as reasonably achievable". The aim of this study was to evaluate the effectiveness of a modified radiation safety protocol in reducing patient dose during paediatric interventional cardiac catheterisation.

METHODS

Radiation dose data were retrospectively extracted from January 2014 to December 2015 (Standard group) and prospectively collected from January 2016 to December 2017 (Low-dose group) after implementation of a modified radiation safety protocol. Both groups included five most common procedures: atrial septal defect closure, patent ductus arteriosus closure, perimembranous ventricular septal defect closure, pulmonary valvuloplasty, and supraventricular tachycardia ablation.

RESULTS

Median air Kerma was 48.4, 50.5, 29.75, 149, 218, and 12.9 mGy for atrial septal defect closure, pulmonary valvuloplasty, patent ductus arteriosus closure <20 kg, ventricular septal defect closure <20 kg, ventricular septal defect closure ≧20 kg, and supraventricular tachycardia ablation in Standard group, respectively, which significantly decreased to 18.75, 20.7, 11.5, 41.9, 117, and 3.3 mGy in Low-dose group (p < 0.05). This represents a reduction in dose to each patient between 46 and 74%. Among five procedural types in Low-dose group, dose of ventricular septal defect closure was the highest with median air Kerma of 62.5 mGy, dose area product of 364.7 μGy.m2, and dose area product per body weight of 21.5 μGy.m2/kg, respectively, along with the longest fluoroscopy time of 9.9 minutes.

CONCLUSION

We provided a feasible radiation safety protocol with specific settings on a case-by-case basis. Increasing awareness and adequate training of a practical radiation dose reduction program are essential to improve radiation protection for children.

Strategies for Minimizing Occupational Radiation Exposure in Cardiac Imaging

PURPOSE OF REVIEW

Radiation safety has been at the center of interest of both researchers and healthcare institutions. This review will summarize and shed light on the various techniques adapted to reduce staff exposure to ionizing radiation (IR) in the field of cardiac imaging.

RECENT FINDINGS

In the last years, with the advance of awareness and the development of new technologies, there have been several tools and techniques adapted. The breakthrough of several technologies to lower radiation dose and shorten the duration of diagnostic tests associated with IR, the use of protection devices by staff members, and mostly the awareness of exposure to IR are the hallmark of these advances. Using all these measures has led to a significant decrease in staff exposure to IR. Reducing staff exposure to meet the "As Low As Reasonably Achievable" principle is feasible. This review introduces the most important strategies applied in cardiac imaging.

Contemporary Cardiac SPECT Imaging-Innovations and Best Practices: An Information Statement from the American Society of Nuclear Cardiology

This information statement from the American Society of Nuclear Cardiology highlights advances in cardiac SPECT imaging and supports the incorporation of new technology and techniques in laboratories performing nuclear cardiology procedures. The document focuses on the application of the latest imaging protocols and the utilization of newer hardware and software options to perform high quality, state-of-the-art SPECT nuclear cardiology procedures. Recommendations for best practices of cardiac SPECT imaging are discussed, highlighting what imaging laboratories should be doing as the standard of care in 2018 to achieve optimal results (based on the ASNC 2018 SPECT guideline [Dorbala et al., J Nucl Cardiol. 2018. https://doi.org/10.1007/s12350-018-1283-y ]).

Spontaneous Coronary Artery Dissection: Current State of the Science: A Scientific Statement From the American Heart Association

Spontaneous coronary artery dissection (SCAD) has emerged as an important cause of acute coronary syndrome, myocardial infarction, and sudden death, particularly among young women and individuals with few conventional atherosclerotic risk factors. Patient-initiated research has spurred increased awareness of SCAD, and improved diagnostic capabilities and findings from large case series have led to changes in approaches to initial and long-term management and increasing evidence that SCAD not only is more common than previously believed but also must be evaluated and treated differently from atherosclerotic myocardial infarction. High rates of recurrent SCAD; its association with female sex, pregnancy, and physical and emotional stress triggers; and concurrent systemic arteriopathies, particularly fibromuscular dysplasia, highlight the differences in clinical characteristics of SCAD compared with atherosclerotic disease. Recent insights into the causes of, clinical course of, treatment options for, outcomes of, and associated conditions of SCAD and the many persistent knowledge gaps are presented.

Reducing radiation exposure during procedures performed in the electrophysiology laboratory

INTRODUCTION

Expert societies recently published strong recommendations to reduce the exposure of patients and staff to ionizing radiation (IR) during interventional and electrophysiology (EP) procedures. However, adherence to these guidelines remains difficult and the impact of implementing such recommendations is poorly characterized.

METHODS AND RESULTS

We conducted a single-center cohort study to quantify radiation exposure over time in three EP laboratories at the Montreal Heart Institute during 5,546 consecutive procedures from 2012 to 2015 by 11 primary operators. Overall, 2,618 (47.2%) procedures were catheter-based and 2,928 (52.8%) were device interventions. Interventions to reduce radiation exposure included educational initiatives to raise awareness (i.e., limiting cine acquisition, patient position, table height), slower frame rate, lower radiation dose per pulse, collimation, and integration with 3-D mapping systems and/or MediGuide technology. An 85% reduction in IR exposure was observed from 2012 to 2015, with the mean dose-area-product (DAP) decreasing from 7.65 ± 0.05 Gy·cm² to 1.15 ± 0.04 Gy·cm² (P < 0.001). This was true for catheter-based procedures (mean DAP 16.99 ± 0.08 to 2.00 ± 0.06 Gy·cm² , P < 0.001) and device interventions (mean DAP 4.18 ± 0.06 to 0.64 ± 0.05 Gy·cm² , P < 0.001). The median effective dose of IR recorded per quarter by 282 cervical dosimeters on EP staff decreased from 0.57 (IQR 0.18, 1.03) mSv in 2012 to 0.00 (IQR 0.00, 0.19) mSv in 2015, P < 0.001.

CONCLUSION

Enforcing good clinical practices with simple measures and low-dose fluoroscopy settings are highly effective in reducing IR exposure in the EP lab. These promising results should encourage other EP labs to adopt similar protective measures.

Cardiac Computed Tomography: Before and After Cardiac Surgery

Cardiac computed tomography angiography (CCTA) is a noninvasive imaging technique that has been rapidly adopted into clinical practice. Over the past decade, technological advances have improved CCTA accuracy, and there is an increasing amount of data supporting its prognostic value in the assessment of coronary artery disease. Recently, "appropriate use criteria" has been used as a tool to minimize inappropriate testing and reduce patient exposure to unnecessary risk and inconclusive studies. This review will summarize the appropriate uses of CCTA in patients before and after cardiac surgery. Although the most common indication for CCTA is assessment of patency of native coronary arteries, other potential perioperative uses (eg, assessment of congenital heart disease, valvular heart disease, pericardial disease, myocardial disease, cardiac anatomy, bypass grafts, aortic disease, and cardiac masses) will be reviewed.

Status of cardiovascular PET radiation exposure and strategies for reduction: An Information Statement from the Cardiovascular PET Task Force

Cardiovascular positron emission tomography (PET) imaging provides high-quality visual and quantitative myocardial perfusion and function images. In addition, cardiovascular PET can assess myocardial viability, myocardial inflammatory disorders such as cardiac sarcoid, and infections of implanted devices including pacemakers, ventricular assist devices, and prosthetic heart valves. As with all nuclear cardiology procedures, the benefits need to be considered in relation to the risks of exposure to radiation. When performed properly, these assessments can be obtained while simultaneously minimizing radiation exposure. The purpose of this information statement is to present current concepts to minimize patient and staff radiation exposure while ensuring high image quality.

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.