Imaging Features of Arrhythmogenic Cardiomyopathies.

Arrhythmogenic cardiomyopathy (ACM) is a genetic disease characterized by replacement of ventricular myocardium with fibrofatty tissue, predisposing the patient to ventricular arrhythmias and/or sudden cardiac death. Most cases of ACM are associated with pathogenic variants in genes that encode desmosomal proteins, an important cell-to-cell adhesion complex present in both the heart and skin tissue. Although ACM was first described as a disease predominantly of the right ventricle, it is now acknowledged that it can also primarily involve the left ventricle or both ventricles. The original right-dominant phenotype is traditionally diagnosed using the 2010 task force criteria, a multifactorial algorithm divided into major and minor criteria consisting of structural criteria based on two-dimensional echocardiographic, cardiac MRI, or right ventricular angiographic findings; tissue characterization based on endomyocardial biopsy results; repolarization and depolarization abnormalities based on electrocardiographic findings; arrhythmic features; and family history. Shortfalls in the task force criteria due to the modern understanding of the disease have led to development of the Padua criteria, which include updated criteria for diagnosis of the right-dominant phenotype and new criteria for diagnosis of the left-predominant and biventricular phenotypes. In addition to incorporating cardiac MRI findings of ventricular dilatation, systolic dysfunction, and regional wall motion abnormalities, the new Padua criteria emphasize late gadolinium enhancement at cardiac MRI as a key feature in diagnosis and imaging-based tissue characterization. Conditions to consider in the differential diagnosis of the right-dominant phenotype include various other causes of right ventricular dilatation such as left-to-right shunts and variants of normal right ventricular anatomy that can be misinterpreted as abnormalities. The left-dominant phenotype can mimic myocarditis at imaging and clinical examination. Additional considerations for the differential diagnosis of ACM, particularly for the left-dominant phenotype, include sarcoidosis and dilated cardiomyopathy. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Epicardial adipose tissue volume is greater in men with severe psoriasis, implying an increased cardiovascular disease risk: A cross-sectional study.

BACKGROUND: Patients with psoriasis have elevated risk of coronary artery disease. OBJECTIVE: Do patients with severe psoriasis have larger epicardial adipose tissue volumes (EAT-V) that are associated with cardiovascular risk? METHODS: For this cross-sectional study, we recruited dermatology patients with severe psoriasis and control patients without psoriasis or rheumatologic disease themselves or in a first-degree relative. Participants aged 34 to 55 years without known coronary artery disease or diabetes mellitus underwent computed tomography (CT); EAT-V was obtained from noncontrast CT heart images. RESULTS: Twenty-five patients with psoriasis (14 men, 11 women) and 16 controls (5 men, 11 women) participated. Groups had no statistical difference in age, body mass index, various cardiovascular risk factors (except high-sensitivity C-reactive protein in men), CT-determined coronary artery calcium scores or plaque, or family history of premature cardiovascular disease. Mean EAT-V was greater in the psoriasis group compared to controls (P = .04). There was no statistically significant difference among women; however, male patients with psoriasis had significantly higher EAT-V than controls (P = .03), even when corrected for elevated high-sensitivity C-reactive protein (P = .05). LIMITATIONS: A single-center convenience sample may not be representative. CONCLUSION: Males with psoriasis without known coronary disease or diabetes had greater EAT-V than controls. EAT-V may be an early identifier of those at increased risk for cardiovascular events.

Understanding Lymphatic Anatomy and Abnormalities at Imaging.

Lymphatic abnormalities encompass a wide range of disorders spanning solitary common cystic lymphatic malformations (LMs) to entities involving multiple organ systems such as lymphangioleiomyomatosis. Many of these disorders are rare, yet some, such as secondary lymphedema from the treatment of malignancy (radiation therapy and/or lymph node dissection), affect millions of patients worldwide. Owing to complex and variable anatomy, the lymphatics are not as well understood as other organ systems. Further complicating this is the variability in the description of lymphatic disease processes and their nomenclature in the medical literature. In recent years, medical imaging has begun to facilitate a deeper understanding of the physiology and pathologic processes that involve the lymphatic system. Radiology is playing an important and growing role in the diagnosis and treatment of many lymphatic conditions. The authors describe both normal and common variant lymphatic anatomy. Various imaging modalities including nuclear medicine lymphoscintigraphy, conventional lymphangiography, and MR lymphangiography used in the diagnosis and treatment of lymphatic disorders are highlighted. The authors discuss imaging many of the common and uncommon lymphatic disorders, including primary LMs described by the International Society for the Study of Vascular Anomalies 2018 classification system (microcystic, mixed, and macrocystic LMs; primary lymphedema). Secondary central lymphatic disorders are also detailed, including secondary lymphedema and chylous leaks, as well as lymphatic disorders not otherwise easily classified. The authors aim to provide the reader with an overview of the anatomy, pathology, imaging findings, and treatment of a wide variety of lymphatic conditions. ©RSNA, 2022.

Lessons Learned from Peer Learning Conference in Cardiothoracic Radiology.

Medical errors may lead to patient harm and may also have a devastating effect on medical providers, who may suffer from guilt and the personal impact of a given error (second victim experience). While it is important to recognize and remedy errors, it should be done in a way that leads to long-standing practice improvement and focuses on systems-level opportunities rather than in a punitive fashion. Traditional peer review systems are score based and have some undesirable attributes. The authors discuss the differences between traditional peer review systems and peer learning approaches and offer practical suggestions for transitioning to peer learning conferences. Peer learning conferences focus on learning opportunities and embrace errors as an opportunity to learn. The authors also discuss various types and sources of errors relevant to the practice of radiology and how discussions in peer learning conferences can lead to widespread system improvement. In the authors' experience, these strategies have resulted in practice improvement not only at a division level in radiology but in a broader multidisciplinary setting as well. The online slide presentation from the RSNA Annual Meeting is available for this article. ©RSNA, 2022.

Myocardial Strain Evaluation with Cardiovascular MRI: Physics, Principles, and Clinical Applications.

Myocardial strain is a measure of myocardial deformation, which is a more sensitive imaging biomarker of myocardial disease than the commonly used ventricular ejection fraction. Although myocardial strain is commonly evaluated by using speckle-tracking echocardiography, cardiovascular MRI (CMR) is increasingly performed for this purpose. The most common CMR technique is feature tracking (FT), which involves postprocessing of routinely acquired cine MR images. Other CMR strain techniques require dedicated sequences, including myocardial tagging, strain-encoded imaging, displacement encoding with stimulated echoes, and tissue phase mapping. The complex systolic motion of the heart can be resolved into longitudinal strain, circumferential strain, radial strain, and torsion. Myocardial strain metrics include strain, strain rate, displacement, velocity, torsion, and torsion rate. Wide variability exists in the reference ranges for strain dependent on the imaging technique, analysis software, operator, patient demographics, and hemodynamic factors. In anticancer therapy cardiotoxicity, CMR myocardial strain can help identify left ventricular dysfunction before the decline of ejection fraction. CMR myocardial strain is also valuable for identifying patients with left ventricle dyssynchrony who will benefit from cardiac resynchronization therapy. CMR myocardial strain is also useful in ischemic heart disease, cardiomyopathies, pulmonary hypertension, and congenital heart disease. The authors review the physics, principles, and clinical applications of CMR strain techniques. Online supplemental material is available for this article. ©RSNA, 2022.

Tracheobronchomalacia and Excessive Dynamic Airway Collapse: Current Concepts and Future Directions.

Tracheobronchomalacia (TBM) and excessive dynamic airway collapse (EDAC) are airway abnormalities that share a common feature of expiratory narrowing but are distinct pathophysiologic entities. Both entities are collectively referred to as expiratory central airway collapse (ECAC). The malacia or weakness of cartilage that supports the tracheobronchial tree may occur only in the trachea (ie, tracheomalacia), in both the trachea and bronchi (TBM), or only in the bronchi (bronchomalacia). On the other hand, EDAC refers to excessive anterior bowing of the posterior membrane into the airway lumen with intact cartilage. Clinical diagnosis is often confounded by comorbidities including asthma, chronic obstructive pulmonary disease, obesity, hypoventilation syndrome, and gastroesophageal reflux disease. Additional challenges include the underrecognition of ECAC at imaging; the interchangeable use of the terms TBM and EDAC in the literature, which leads to confusion; and the lack of clear guidelines for diagnosis and treatment. The use of CT is growing for evaluation of the morphology of the airway, tracheobronchial collapsibility, and extrinsic disease processes that can narrow the trachea. MRI is an alternative tool, although it is not as widely available and is not used as frequently for this indication as is CT. Together, these tools not only enable diagnosis, but also provide a road map to clinicians and surgeons for planning treatment. In addition, CT datasets can be used for 3D printing of personalized medical devices such as stents and splints. An invited commentary by Brixey is available online. Online supplemental material is available for this article. ©RSNA, 2022.

Desmoplakin Cardiomyopathy, a Fibrotic and Inflammatory Form of Cardiomyopathy Distinct From Typical Dilated or Arrhythmogenic Right Ventricular Cardiomyopathy.

BACKGROUND: Mutations in desmoplakin (DSP), the primary force transducer between cardiac desmosomes and intermediate filaments, cause an arrhythmogenic form of cardiomyopathy that has been variably associated with arrhythmogenic right ventricular cardiomyopathy. Clinical correlates of DSP cardiomyopathy have been limited to small case series. METHODS: Clinical and genetic data were collected on 107 patients with pathogenic DSP mutations and 81 patients with pathogenic plakophilin 2 (PKP2) mutations as a comparison cohort. A composite outcome of severe ventricular arrhythmia was assessed. RESULTS: DSP and PKP2 cohorts included similar proportions of probands (41% versus 42%) and patients with truncating mutations (98% versus 100%). Left ventricular (LV) predominant cardiomyopathy was exclusively present among patients with DSP (55% versus 0% for PKP2, P<0.001), whereas right ventricular cardiomyopathy was present in only 14% of patients with DSP versus 40% for PKP2 (P<0.001). Arrhythmogenic right ventricular cardiomyopathy diagnostic criteria had poor sensitivity for DSP cardiomyopathy. LV late gadolinium enhancement was present in a primarily subepicardial distribution in 40% of patients with DSP (23/57 with magnetic resonance images). LV late gadolinium enhancement occurred with normal LV systolic function in 35% (8/23) of patients with DSP. Episodes of acute myocardial injury (chest pain with troponin elevation and normal coronary angiography) occurred in 15% of patients with DSP and were strongly associated with LV late gadolinium enhancement (90%), even in cases of acute myocardial injury with normal ventricular function (4/5, 80% with late gadolinium enhancement). In 4 DSP cases with 18F-fluorodeoxyglucose positron emission tomography scans, acute LV myocardial injury was associated with myocardial inflammation misdiagnosed initially as cardiac sarcoidosis or myocarditis. Left ventricle ejection fraction <55% was strongly associated with severe ventricular arrhythmias for DSP cases (P<0.001, sensitivity 85%, specificity 53%). Right ventricular ejection fraction <45% was associated with severe arrhythmias for PKP2 cases (P<0.001) but was poorly associated for DSP cases (P=0.8). Frequent premature ventricular contractions were common among patients with severe arrhythmias for both DSP (80%) and PKP2 (91%) groups (P=non-significant). CONCLUSIONS: DSP cardiomyopathy is a distinct form of arrhythmogenic cardiomyopathy characterized by episodic myocardial injury, left ventricular fibrosis that precedes systolic dysfunction, and a high incidence of ventricular arrhythmias. A genotype-specific approach for diagnosis and risk stratification should be used.

Multimodality Imaging of Transposition of the Great Arteries.

Transposition of the great arteries (TGA) is a congenital conotruncal abnormality characterized by discordant connections between the ventricles and great arteries, with the aorta originating from the right ventricle (RV), and the pulmonary artery (PA) originating from the left ventricle (LV). The two main types of TGA are complete transposition or dextro-transposition of the great arteries (D-TGA), commonly referred to as d-loop, and congenitally corrected transposition (CCTGA), commonly referred to as l-loop or L-TGA. In D-TGA, the connections between the ventricles and atria are concordant, whereas in CCTGA they are discordant, with the left atrium connected to the RV, and the right atrium connected to the LV. D-TGA manifests during the neonatal period and can be surgically managed by atrial switch operation (AtrSO), arterial switch operation (ASO), Rastelli procedure, or Nikaidoh procedure. Arrhythmia, systemic ventricular dysfunction, baffle stenosis, and baffle leak are the common complications of AtrSO, whereas supravalvular pulmonary or branch PA stenosis, neoaortic dilatation, and coronary artery narrowing are the common complications of ASO. CCTGA may manifest late in life, even in adulthood. Surgeries for associated lesions such as tricuspid regurgitation, subpulmonic stenosis, and ventricular septal defect may be performed. A double-switch operation that includes both the atrial and arterial switch operations constitutes anatomic correction for CCTGA. Imaging plays an important role in the evaluation of TGA, both before and after surgery, for helping define the anatomy, quantify hemodynamics, and evaluate complications. Transthoracic echocardiography is the first-line imaging modality for presurgical planning in children with TGA. MRI provides comprehensive morphologic and functional information, particularly in adults after surgery. CT is performed when MRI is contraindicated or expected to generate artifacts. The authors review the imaging appearances of TGA, with a focus on pre- and postsurgical imaging. Online supplemental material is available for this article. ©RSNA, 2021.

Improving MR Image Quality in Patients with Metallic Implants.

The number of implanted devices such as orthopedic hardware and cardiac implantable devices continues to increase with an increase in the age of the patient population, as well as an increase in the number of indications for specific devices. Many patients with these devices have or will develop clinical conditions that are best depicted at MRI. However, implanted devices containing paramagnetic or ferromagnetic substances can cause significant artifact, which could limit the diagnostic capability of this modality. Performing imaging with MRI when an implant is present may be challenging, and there are numerous techniques the radiologist and technologist can use to help minimize artifacts related to implants. First, knowledge of the presence of an implant before patient arrival is critical to ensure safety of the patient when the device is subjected to a strong magnetic field. Once safety is ensured, the examination should be performed with the MRI system that is expected to provide the best image quality. The selection of the MRI system includes multiple considerations such as the effects of field strength and availability of specific sequences, which can reduce metal artifact. Appropriate patient positioning, attention to MRI parameters (including bandwidth, voxel size, and echo), and appropriate selection of sequences (those with less metal artifact and advanced metal reduction sequences) are critical to improve image quality. Patients with implants can be successfully imaged with MRI with appropriate planning and understanding of how to minimize artifacts. This improves image quality and the diagnostic confidence of the radiologist. ©RSNA, 2021.

Differences in Pulmonary and Systemic Flow Measurements by Cardiac Magnetic Resonance vs Cardiac Catheterization and Relation to Collateral Flow in Single Ventricle Patients.

Both cardiac magnetic resonance (CMR) and cardiac catheterization (cath) may assess patients with single ventricle physiology prior to stage II or Fontan palliation. However, development of significant aortopulmonary collaterals may invalidate assumptions of the Fick method. We compared CMR and cath flow measurements and evaluated the relation to collateral flow. This single-center study included all pre-stage II and pre-Fontan patients between 2010 and 2017 with CMR and cath within 1 month. Pulmonary (Qp) and systemic flow (Qs) by cath were calculated by Fick method. CMR Qp was calculated by total pulmonary venous flow, and Qs by total vena caval flow. Collateral flow by CMR was the difference of pulmonary vein and pulmonary artery flow. In 26 studies (16 pre-stage II and 10 pre-Fontan) in 21 patients, collateral flow was higher in pre-Fontan patients (1.8 ± 0.6 vs 0.9 ± 0.8 L/min/m2, p = 0.01). Overall, CMR and cath had good agreement for Qs and Qp:Qs, with moderate correlation (r = 0.44, p = 0.02 for Qs, r = 0.48, p = 0.02 for Qp:Qs). In pre-Fontan but not in pre-stage II patients, CMR had higher Qp (mean difference - 1.71 L/min/m2) and Qp:Qs (mean difference - 0.36). The underestimation of cath Qp correlated with amount of collateral flow (r = - 0.47, p = 0.02). Neither cath nor CMR flow measurements correlated with outcomes in this small cohort. In conclusion, collaterals lead to systematically higher Qp and Qp:Qs measurements by CMR vs cath in single ventricle patients. Measurements may not be used interchangeably, with potential clinical significance in estimating pulmonary vascular resistance. Further study is necessary to evaluate possible relation to clinical outcomes.

Neo-aortic Root Dilatation, Aortic Stiffness, and Ventricular interactions in Long-Term Follow-Up After the Ross Procedure in Childhood.

Patients after the Ross procedure are at risk for right (RV) and left ventricular (LV) dysfunction due to neo-aortic and pulmonary dysfunction. While neo-aortic root dilatation has been related to LV dysfunction, the potential contributions of aortic stiffness and ventricular interactions have not been evaluated. Patients status post Ross procedure up to age 18 years with cardiac magnetic resonance (CMR) exam from 2007 to 2018 were retrospectively reviewed. Aortic pulse wave velocity (PWV) was calculated from phase contrast and angiogram images. RV and LV peak global longitudinal (GLS) and circumferential strain (GCS) were measured using tissue tracking software. Multivariable regression was performed for variables associated with parameters of LV function. In 58 patients (median age 20.5 years at CMR exam), male gender, longer time since Ross procedure, aortic root dilatation, and lower RV ejection fraction (EF) were associated with decreased LV EF. There was no association with LV late gadolinium enhancement or neo-aortic or conduit regurgitation. LV GCS and GLS also correlated with RV GCS, RV GLS and PWV. In multivariable analysis, the relation of RV and LV systolic function, but not aortic measurements, remained significant. In conclusion, in long-term follow-up after pediatric Ross procedure, RV function rather than aortic root size or aortic stiffness most closely relates to LV function. Ventricular interactions may impact decision-making on timing of conduit intervention, which could differ from established criteria in populations with only aortic or pulmonary valve disease. Further study is warranted to evaluate possible association with clinical outcome.

Role of Radiologists in the Diagnosis of Unsuspected Birt-Hogg-Dubé Syndrome in a Tertiary Clinical Practice.

OBJECTIVE. Birt-Hogg-Dubé (BHD) syndrome is considered rare. Growing evidence indicates that it is underdiagnosed. The purpose of this study is to ascertain the impact of radiology reports that suggest the possibility of BHD syndrome on downstream management and a final diagnosis of BHD syndrome. MATERIALS AND METHODS. In this retrospective study, electronic medical records were searched to identify radiology reports suggesting the possibility of BHD syndrome in patients without a known or suspected diagnosis. Clinical and demographic information, the specialty of the ordering clinician, and imaging findings and confidence conveyed in the radiology report (with BHD syndrome listed as the most likely diagnosis versus one among several possibilities but not as the leading diagnosis) were recorded. The resultant downstream evaluations that were captured included referral for genetic evaluation and subsequent diagnosis of BHD. RESULTS. Between 2004 and 2016, radiologists suggested a diagnosis of BHD syndrome in 87 patients. Of these patients, 15% (13/87) underwent genetic evaluation, and 54% of those patients (7/13) had positive findings. Genetic evaluation was more likely for patients with a history of pneumothorax (p = 0.004) or involvement of the lungs and kidneys (p = 0.003). The urology department referred the highest percentage of patients (31% [4/13]) for genetic evaluation. CONCLUSION. Radiologists have a unique opportunity to suggest BHD syndrome, allowing appropriate genetic testing, screening, and counseling of patients and their families. Clinical presentation, including a history of pneumothorax and involvement of both the lungs and kidneys on imaging, may determine which patients are ultimately referred for genetic evaluation. We hope that increasing awareness that BHD syndrome is not so rare may lead to early diagnosis.

Translation of Quantitative Imaging Biomarkers into Clinical Chest CT.

Quantitative imaging has been proposed as the next frontier in radiology as part of an effort to improve patient care through precision medicine. In 2007, the Radiological Society of North America launched the Quantitative Imaging Biomarkers Alliance (QIBA), an initiative aimed at improving the value and practicality of quantitative imaging biomarkers by reducing variability across devices, sites, patients, and time. Chest CT occupies a strategic position in this initiative because it is one of the most frequently used imaging modalities, anatomically encompassing the leading causes of mortality worldwide. To date, QIBA has worked on profiles focused on the accurate, reproducible, and meaningful use of volumetric measurements of lung lesions in chest CT. However, other quantitative methods are on the verge of translation from research grounds into clinical practice, including (a) assessment of parenchymal and airway changes in patients with chronic obstructive pulmonary disease, (b) analysis of perfusion with dual-energy CT biomarkers, and (c) opportunistic screening for coronary atherosclerosis and low bone mass by using chest CT examinations performed for other indications. The rationale for and the key facts related to the application of these quantitative imaging biomarkers in cardiothoracic chest CT are presented. ©RSNA, 2019 See discussion on this article by Buckler (pp 977-980).

Phase-Contrast Magnetic Resonance Quantification of Aortic Regurgitation in Patients With Turbulent Aortic Flow.

OBJECTIVE: This study aimed to assess variability in measurements and accurately quantify aortic regurgitation in patients with coexisting turbulent aortic flow using phase-contrast magnetic resonance. METHODS: All patients (n = 21) underwent phase-contrast magnetic resonance at 2 or more sites: ascending aorta, sinuses of Valsalva, and left ventricular outflow tract. The net flow/minute (NF), forward flow/minute (FF), regurgitant flow/minute (RF), and regurgitant fraction (RF%) were compared with the sum of superior vena cava and descending aortic flow/minute, left ventricular cardiac output, difference between the 2, and percentage difference, respectively. RESULTS: The NF, FF, and RF were significantly different between each site. The combination of FF in the left ventricular outflow tract and NF from the superior vena cava + descending aorta provided the best reliability of RF and regurgitant fraction (intraclass correlation coefficients, 0.881 [95% confidence interval, 0.882-0.878] and 0.838 [95% confidence interval, 0.837-0.838]). CONCLUSION: Combining flow measurements from more than 1 site provides the most accurate quantification of aortic regurgitation in patients with turbulent aortic flow.

Differential Myocardial Mechanics in Volume and Pressure Loaded Right Ventricles Demonstrated by Cardiac Magnetic Resonance.

In patients with D-looped transposition of the great arteries (D-TGA) status post atrial switch operation, the systemic right ventricle (RV) shifts to predominantly circumferential (CS) rather than longitudinal strain (LS), which may represent adaptation or dysfunction. We aimed to evaluate myocardial mechanics in pressure loaded, volume-loaded, and normal RVs by cardiac magnetic resonance (CMR). Patients with D-TGA post atrial switch operation with CMR from 2008 to 2015 were matched 1:1 for age and RV ejection fraction (EF) with repaired tetralogy of Fallot (TOF) patients (volume-loaded RVs), and 1:1 for age with control patients. RV free wall LS and CS were measured using feature tracking software (TomTec, Unterscleissheim, Germany). A total of 32 D-TGA (median age 32 years, 56% male), 32 TOF, and 32 control patients were included. D-TGA patients had less dilatation than TOF patients (125 ± 35 ml/m2 vs. 149 ± 44 ml/m2, p = 0.02) and lower RVEF than controls (42.9 ± 7.7% vs. 56.3 ± 5.6%, p < 0.0001). RV LS was similar in D-TGA and TOF ( - 13.2 ± 4.5% vs. - 14.5 ± 5.9%, p = 0.32), both decreased compared to controls. However, CS in D-TGA was higher than controls ( - 14.1 ± 4.1% vs. - 11.4 ± 4.4%, p = 0.01), with a higher CS:LS ratio (1.2 ± 0.7 vs. 0.6 ± 0.3, p < 0.0001), while CS in TOF and controls did not differ. RVEF in D-TGA correlated closely with CS (r = - 0.85, p < 0.0001) but not LS (r = 0.10, p = 0.58). I n conclusion, CMR can differentiate strain patterns in pressure- and volume-loaded RVs, with decreased LS in both conditions, while systemic RVs compensate with supra-normal CS. CS may be a more clinically relevant measure of RV function in this population.

Primary cardiac tumors associated with genetic syndromes: a comprehensive review.

Various cardiac tumors occur in the setting of a genetic syndrome such as myxomas in Carney complex and rhabdomyomas in tuberous sclerosis. Tumor biology can be different in syndromic forms, and on imaging children sometimes demonstrate additional manifestations of the underlying syndrome. We discuss the imaging appearance of cardiac tumors occurring in the framework of a genetic syndrome, the findings that suggest an underlying syndrome, and the impact on management.

Anomalous Coronary Arteries That Need Intervention: Review of Pre- and Postoperative Imaging Appearances.

Coronary artery anomalies constitute a diverse group of abnormalities, ranging from anatomic variants to those having hemodynamic consequences. This review focuses on major anomalies that have clinical implications requiring treatment, including anomalous origin of the coronary artery from the opposite sinus with interarterial course specifically with an intramural course, coronary artery origin from the pulmonary artery, and coronary artery fistula. Comprehensive imaging evaluation is necessary to precisely delineate the anatomy as well as pathophysiologic aspects of the anomaly before determining treatment options for a specific patient. Coronary computed tomographic angiography provides elegant depiction of coronary arterial anatomy and the relationship of the vessel to the adjacent structures, with the ability to perform three-dimensional reconstructions. Magnetic resonance (MR) imaging is emerging as an alternative noninvasive imaging strategy, particularly in young individuals, due to the lack of ionizing radiation and avoidance of iodinated contrast agents. This review describes the roles and recent technical advancements in computed tomography and MR imaging pertinent to coronary artery imaging. Additionally, this article will familiarize readers with the cross-sectional imaging appearance of clinically relevant coronary anomalies, hemodynamic considerations, and complex decision making. The different management strategies used for these anomalies, such as coronary unroofing, reimplantation, bypass grafting, Takeuchi repair, and surgical and interventional closure of fistulas, as well as specific posttreatment complications, are also discussed. ©RSNA, 2017.

Predictors of missed appointments in patients referred for congenital or pediatric cardiac magnetic resonance.

BACKGROUND: Congenital cardiac magnetic resonance is a limited resource because of scanner and physician availability. Missed appointments decrease scheduling efficiency, have financial implications and represent missed care opportunities. OBJECTIVE: To characterize the rate of missed appointments and identify modifiable predictors. MATERIALS AND METHODS: This single-center retrospective study included all patients with outpatient congenital or pediatric cardiac MR appointments from Jan. 1, 2014, through Dec. 31, 2015. We identified missed appointments (no-shows or same-day cancellations) from the electronic medical record. We obtained demographic and clinical factors from the medical record and assessed socioeconomic factors by U.S. Census block data by patient ZIP code. Statistically significant variables (P<0.05) were included into a multivariable analysis. RESULTS: Of 795 outpatients (median age 18.5 years, interquartile range 13.4-27.1 years) referred for congenital cardiac MR, a total of 91 patients (11.4%) missed appointments; 28 (3.5%) missed multiple appointments. Reason for missed appointment could be identified in only 38 patients (42%), but of these, 28 (74%) were preventable or could have been identified prior to the appointment. In multivariable analysis, independent predictors of missed appointments were referral by a non-cardiologist (adjusted odds ratio [AOR] 5.8, P=0.0002), referral for research (AOR 3.6, P=0.01), having public insurance (AOR 2.1, P=0.004), and having scheduled cardiac MR from November to April (AOR 1.8, P=0.01). CONCLUSION: Demographic factors can identify patients at higher risk for missing appointments. These data may inform initiatives to limit missed appointments, such as targeted education of referring providers and patients. Further data are needed to evaluate the efficacy of potential interventions.