Recommendations for cardiovascular magnetic resonance and computed tomography in congenital heart disease: a consensus paper from the CMR/CCT Working Group of the Italian Society of Pediatric Cardiology and the Italian College of Cardiac Radiology endorsed by the Italian Society of Medical and Interventional Radiology (Part II)

Cardiovascular magnetic resonance (CMR) and computed tomography (CCT) are advanced imaging modalities that recently revolutionized the conventional diagnostic approach to congenital heart diseases (CHD), supporting echocardiography and often replacing cardiac catheterization. This is the second of two complementary documents, endorsed by experts from the Working Group of the Italian Society of Pediatric Cardiology and the Italian College of Cardiac Radiology of the Italian Society of Medical and Interventional Radiology, aimed at giving updated indications on the appropriate use of CMR and CCT in different clinical CHD settings, in both pediatrics and adults. In this article, support is also given to radiologists, pediatricians, cardiologists, and cardiac surgeons for indications and appropriateness criteria for CMR and CCT in the most referred CHD, following the proposed new criteria presented and discussed in the first document. This second document also examines the impact of devices and prostheses for CMR and CCT in CHD and additionally presents some indications for CMR and CCT exams when sedation or narcosis is needed.

A Case Report of an Uncommon Association of Total Intracardiac Anomalous Pulmonary Venous Return and Tetralogy of Fallot

Total anomalous pulmonary venous return (TAPVR) represents a group of anomalies consisting of a lack of connection between the pulmonary veins and the left atrium. All oxygenated pulmonary venous return flows directly or indirectly into the right atrium. Survival is only possible with a right-to-left atrial shunt. It remains rare, accounting for less than 1% of all congenital heart diseases. Its association with tetralogy of Fallot is much rarer and has been documented in medical literature as isolated cases. Early prenatal diagnosis, rapid surgical repair, and optimal postoperative resuscitation appear to be the best guarantee of a favorable outcome following total repair of a pulmonary venous connection anomaly. Non-obstructed forms present as high-flow shunts with moderate cyanosis. The symptomatology of blocked forms is dominated by the obstruction to venous return; a clinical picture of respiratory distress with intense cyanosis and severe pulmonary arterial hypertension develops from the first days of life. Echocardiography is fundamental in diagnosing TAPVR. If the results are inconclusive, magnetic resonance imaging and computed tomography are appropriate alternatives for establishing a complete and accurate diagnosis. We report a case of a two-month and 22-day-old infant who is a product of a twin pregnancy, presenting with a non-obstructed TAPVR associated with tetralogy of Fallot, and his twin who died on day 20 of life, likely due to a complex cyanotic congenital heart disease.

ACR Appropriateness Criteria® Congenital or Acquired Heart Disease

Pediatric heart disease is a large and diverse field with an overall prevalence estimated at 6 to 13 per 1,000 live births. This document discusses appropriateness of advanced imaging for a broad range of variants. Diseases covered include tetralogy of Fallot, transposition of great arteries, congenital or acquired pediatric coronary artery abnormality, single ventricle, aortopathy, anomalous pulmonary venous return, aortopathy and aortic coarctation, with indications for advanced imaging spanning the entire natural history of the disease in children and adults, including initial diagnosis, treatment planning, treatment monitoring, and early detection of complications. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Evaluation of paediatric pulmonary vein stenosis by cardiac CT angiography: a comparative study with transthoracic echocardiography and catheter angiogram

AIM

To compare prospective electrocardiogram (ECG)-gated cardiac computed tomographic angiography (CCTA) with transthoracic echocardiography (TTE) and cardiac catheter angiography (CCA) for paediatric pulmonary vein (PV) stenosis.

MATERIALS AND METHODS

Retrospective chart review was undertaken of all patients who underwent CCTA for PV evaluation over a 4-year period. Patient demographics, findings of CCTA, TTE, and CCA, as well as interventions performed, were recorded for each PV.

RESULTS

Thirty-five patients were included (23 male patients). All patients had a prior TTE with time interval between TTE and CCTA ranging from 0 to 90 days. CCTA detected 92 abnormalities in 32 patients. TTE missed 16 PV abnormalities (16/92, 17%), detected 37 abnormalities with certainty (37/92, 40%), and was suggestive in 39 abnormalities (39/92, 42%). CCTA was negative for PV abnormalities when TTE was positive or suspicious in three patients. Nineteen patients underwent CCA (18 patients with 52 abnormalities and one patient with normal PV), confirming CCTA findings. Thirty-nine were treated with angioplasty/stenting (39/52,75%). Failed recanalisation occurred in three PVs (3/52, 6%) and no intervention was attempted for the rest as the gradient was not significant (10/52,19%). Nine patients underwent surgical repair (26/92, 28%). Five patients (14/92, 15%) were managed with no intervention based on CCTA findings and poor clinical prognosis.

CONCLUSIONS

CCTA plays an important role in detecting paediatric PV stenosis and identifies additional findings compared to TTE that have direct surgical/interventional implications. CCTA complements TTE in imaging these patients and helps guide management.

Multimodality diagnostic imaging for anomalous pulmonary venous connections: a pictorial essay

Anomalous pulmonary venous connections represent a heterogeneous group of congenital heart diseases in which a part or all pulmonary venous flow drains directly or indirectly into the right atrium. Clinically, anomalous pulmonary venous connections may be silent or have variable consequences, including neonatal cyanosis, volume overload and pulmonary arterial hypertension due to the left-to-right shunt. Anomalous pulmonary venous connections are frequently associated with other congenital cardiac defects and their accurate diagnosis is crucial for treatment planning. Therefore, multimodality diagnostic imaging, comprising a combination (but not all) of echocardiography, cardiac catheterization, cardiothoracic computed tomography and cardiac magnetic resonance imaging, helps identify potential blind spots relevant to each imaging modality before treatment and achieve optimal management and monitoring. For the same reasons, diagnostic imaging evaluation using a multimodality fashion should be used after treatment. Finally, those interpreting the images should be familiar with the various surgical approaches used to repair anomalous pulmonary venous connections and the common postoperative complications.

The so-called absorption process of the pulmonary vein into the left atrium of the heart: a histological study using human embryos and fetuses

BACKGROUND

Embryonic pulmonary veins (PVs) are believed to be absorbed into the left atrium (LA) to provide an adult morphology in which "four" veins drain separately into the atrium.

MATERIALS AND METHODS

Serial histological sections were obtained from 27 human embryos and fetuses.

RESULTS

Between 5 and 6 weeks, the four PVs joined together to form a trunk-like structure (initial spatium pulmonalis) that was larger than the initial LA (two-ostia pattern). The cardiac nerves ran inferiorly along the posterior aspect of the four veins, as well as the spatium. At and until 7 weeks, the cardiac nerves were concentrated to elongate the nerve fold, and the latter separated the left PV trunk from the expanding LA (left spatium). Similarly, the right PV opened to a thick and deep LA recess (right spatium). At 8-12 weeks, depending on the growth of the LA, the opening of the left and right PVs became distant, and the spatium was elongated transversely. The left spatium was enlarged to open widely to the proper left atrium in contrast to the right spatium pushed anteriorly by the right atrium. The three-ostia pattern was transiently observed because of the lost delimitation between the left spatium and proper atrium. The myocardium was thin in the left spatium behind the left atrial nerve fold, whereas the right spatium was tube-like with a thick myocardium.

CONCLUSIONS

The four-ostia pattern seemed to be established at birth due to a drastically increased venous return from the lung, resulting in a flat smooth left atrial posterior wall.

Benefit of stereoscopic volume rendering for the identification of pediatric pulmonary vein stenosis from CT angiography

The use of three-dimensional (3D) technologies in medical practice is increasing; however, its use is largely untested. One 3D technology, stereoscopic volume-rendered 3D display, can improve depth perception. Pulmonary vein stenosis (PVS) is a rare cardiovascular pathology, often diagnosed by computed tomography (CT), where volume rendering may be useful. Depth cues may be lost when volume rendered CT is displayed on regular screens instead of 3D displays. The objective of this study was to determine whether the 3D stereoscopic display of volume-rendered CT improved perception compared to standard monoscopic display, as measured by PVS diagnosis. CT angiograms (CTAs) from 18 pediatric patients aged 3 weeks to 2 years were volume rendered and displayed with and without stereoscopic display. Patients had 0 to 4 pulmonary vein stenoses. Participants viewed the CTAs in 2 groups with half on monoscopic and half on stereoscopic display and the converse a minimum of 2 weeks later, and their diagnoses were recorded. A total of 24 study participants, comprised of experienced staff cardiologists, cardiovascular surgeons and radiologists, and their trainees viewed the CTAs and assessed the presence and location of PVS. Cases were classified as simple (2 or fewer lesions) or complex (3 or more lesions). Overall, there were fewer type 2 errors in diagnosis for stereoscopic display than standard display, an insignificant difference (p = 0.095). There was a significant decrease in type 2 errors for complex multiple lesion cases (≥3) vs simpler cases (p = 0.027) and improvement in localization of pulmonary veins (p = 0.011). Subjectively, 70% of participants stated that stereoscopy was helpful in the identification of PVS. The stereoscopic display did not result in significantly decreased errors in PVS diagnosis but was helpful for more complex cases.

Total Anomalous Pulmonary Venous Return

Supplemental material is available for this article.

Ferumoxytol-Enhanced Cardiac Magnetic Resonance Angiography and 4D Flow: Safety and Utility in Pediatric and Adult Congenital Heart Disease

Cardiac magnetic resonance imaging and angiography have a crucial role in the diagnostic evaluation and follow up of pediatric and adult patients with congenital heart disease. Although much of the information required of advanced imaging studies can be provided by standard gadolinium-enhanced magnetic resonance imaging, the limitations of precise bolus timing, long scan duration, complex imaging protocols, and the need to image small structures limit more widespread use of this modality. Recent experience with off-label diagnostic use of ferumoxytol has helped to mitigate some of these barriers. Approved by the U.S. FDA for intravenous treatment of anemia, ferumoxytol is an ultrasmall superparamagnetic iron oxide nanoparticle that has a long blood pool residence time and high relaxivity. Once metabolized by macrophages, the iron core is incorporated into the reticuloendothelial system. In this work, we aim to summarize the evolution of ferumoxytol-enhanced cardiovascular magnetic resonance imaging and angiography and highlight its many applications for congenital heart disease.

Infra-cardiac TAPVC with an intrahepatic portosystemic shunt: A rare association

Total anomalous pulmonary venous connection (TAPVC) is an uncommonly encountered cyanotic congenital heart disease characterized by anomalous drainage of the pulmonary veins. Concomitant venous anomalies are rarely found in these patients. We present a case of an infra-cardiac TAPVC with an intrahepatic portosystemic shunt, where a vascular channel was seen between the middle hepatic vein and the left branch of the portal vein with fusiform dilatation of the latter, diagnosed on computed tomography angiography.

Case Report: A Huge Calabash Heart: A Rare Case of Supracardiac Total Anomalous Pulmonary Venous Return

A 46-year-old woman was admitted to the cardiovascular department because of a 3-month history of palpitations and exertional dyspnea. She had a history of a successful pregnancy at a very young age. The chest radiograph presented a “calabash” configuration. Echocardiogram discovered a large atrial septal defect with a suspected pulmonary vein abnormality. Cardiac CT revealed supracardiac total anomalous pulmonary venous return, whereby, all the pulmonary veins drain into a vertical vein and, finally, to the superior vena cava. Cardiac catheterization was consistent with anomalous pulmonary venous drainage without pulmonary hypertension. Finally, she underwent a successful surgical repair and appeared asymptomatic before her discharge.

Multimodality imaging in delineation of complex sinus venosus defects and treatment outcomes over the last decade

BACKGROUND

Diagnosis of sinus venosus defects, not infrequently associated with complex anomalous pulmonary venous drainage, may be delayed requiring multimodality imaging.

METHODS

Retrospective review of all patients from February 2008 to January 2019.

RESULTS

Thirty-seven children were diagnosed at a median age of 4.2 years (range 0.5-15.5 years). In 32 of 37 (86%) patients, diagnosis was achieved on transthoracic echocardiography, but five patients (14%) had complex variants (four had high insertion of anomalous vein into the superior caval vein and three had multiple anomalous veins draining to different sites, two of whom had drainage of one vein into the high superior caval vein). In these five patients, the final diagnosis was achieved by multimodality imaging and intra-operative findings. The median age at surgery was 5.2 years (range 1.6-15.8 years). Thirty-one patients underwent double patch repair, four patients a Warden repair, and two patients a single-patch repair. Of the four Warden repairs, two patients had a high insertion of right-sided anomalous pulmonary vein into the superior caval vein, one patient had bilateral superior caval veins, and one patient had right lower pulmonary vein insertion into the right atrium/superior caval vein junction. There was no post-operative mortality, reoperation, residual shunt or pulmonary venous obstruction. One patient developed superior caval vein obstruction and one patient developed atrial flutter.

CONCLUSION

Complementary cardiac imaging modalities improve diagnosis of complex sinus venosus defects associated with a wide variation in the pattern of anomalous pulmonary venous connection. Nonetheless, surgical treatment is associated with excellent outcomes.

Technical Feasibility on the Use of Optical Coherence Tomography in the Evaluation of Pediatric Pulmonary Venous Stenosis

Pulmonary vein stenosis (PVS) in children is a morbid disease and limited progress has been made in improving outcomes for this heterogenous group of patients. Evaluation is currently limited to imaging techniques that fail to provide an adequate overview of the intraluminal and luminal pathology perpetuating our limited understanding of this condition. Optical coherence tomography (OCT) is an imaging modality which provides intraluminal profiling with microstructural detail through optical reflective technology. We sought to evaluate whether its use was technically feasible in pediatric PVS and whether the imaging data provided potentially useful outputs for clinical utility. Eleven patients were prospectively selected from our cardiac catheterization for OCT evaluation of their pulmonary veins (PV) during elective catheterization for PVS. Measurements were taken both pre and post intervention using both manual and automated tools. Stent morphology was characterized. Eleven patients had evaluation of 34 pulmonary veins, with 7 patients having more than one assessment, for a total of 25 overall catheterizations. Most patients were female (75%). Median age at cardiac catheterization was 35 months (range 5-45 months). Median weight of subjects was 10.6 kg (3.7-14.2) with a median BSA documented at 0.505 m² (0.21-0.57). Median number of pulmonary veins involved was 3, (range 1-5 veins) and median contrast volume of 2.9 mL/kg (0.7-3.7) given. Median radiation dose (DAP) was 6095 µGy·cm² (1670-12,400). Median number of previous cardiac catheterizations was 7 (range 1-11). All of the vessels with a diameter < 5 mm were adequately visualized. Of all the OCT images acquired, in 15 vessels (44%) contrast was used to clear the vessels from blood as an angiogram was required at the time, in the other 19 vessels (56%), saline was used with adequate imaging. There were no complications related to OCT. OCT is technically feasible to use in pediatric patients without any directly related complications. It provides intraluminal anatomy in children with both native and treated pulmonary venous stenosis when vessel size is less than 5 mm.

Extremely tortuous vertical vein in supracardiac totally anomalous pulmonary venous connection

We present a case of a 2-month-old boy with supracardiac totally anomalous pulmonary venous connection where computed tomography angiography demonstrated an extremely tortuous course of the vertical vein before its drainage into the left brachiocephalic vein.

Malposition of septum primum in isolated dextrocardia: unique and rare form of anomalous pulmonary venous return in association with partial absence of pericardium-case report

BACKGROUND

Total anomalous pulmonary venous return (TAPVR) refers to an anomaly in which all of the pulmonary veins drain directly or indirectly to the systemic venous circulation. However, unusual types constitute approximately 5% or less of TAPVRs and there may be obstruction or discontinuity of pulmonary vein at various levels.

CASE PRESENTATION

A 3-month-old infant was presented to us with history of poor feeding, respiratory distress and desaturations. The routine echocardiographic investigation initially confirmed the diagnosis of an atrial septal defect with dextrocardia. However, due to disproportionate severity of symptoms and congestive heart failure a cardiac computer tomography angiogram was done that revealed a rare finding of connection of pulmonary veins fused with the posterior atrium, but on the rightward side of the deviated atrial septum. Therefore, pulmonary veins entered a sinus that drains directly into the right atrial superior-posterior wall. During surgical repair, we found an area of absent pericardium in the diaphragmatic surface of the heart. The patient underwent total repair of the TAPVR and patch reconstruction of the pericardial defect. The patient is doing well at 6-month follow up.

CONCLUSIONS

The septum primum malposition defect resulting in TAPVR is a very rare congenital anomaly that can be rarely seen without any heterotaxy. The anomalous features including absent pericardium and dextrocardia were present in this patient have not been described previously with TAPVR. Therefore, we have hypothesized the embryological correlation of absent pericardium and cardiac malposition in such case. Transthoracic echocardiography with Doppler interrogation is a reliable method for diagnosing this condition. In case of suboptimal echocardiographic image due to cardiac position, unclear anatomy or unexplained symptoms, advanced imaging such as computer tomographic angiography or cardiac magnetic resonance imaging can be very helpful. Preoperative proper diagnosis of this anomaly facilitates successful surgical management with excellent outcome.

Pulmonary Vein Stenosis in Children: A Programmatic Approach Employing Primary and Anatomic Therapy

Pulmonary vein stenosis (PVS) is a difficult condition to treat due to recurrence and progression. In 2017, we developed a comprehensive PVS Program at our center to address the multidisciplinary needs of these patients. We discuss the components of our program and our approach to these patients, using a combination of primary (medical) therapy in addition to anatomic therapy to preserve vessel patency. A multidisciplinary approach to treating these challenging patients is critical.

Perioperative Anomalous Pulmonary Venous Return Evaluation With Low-Dose Cardiac Computed Tomography

BACKGROUND

Low-dose multidetector computed tomographic angiography (MDCTA) is playing an increasingly larger role in the diagnosis of anomalous pulmonary venous return (APVR). Despite advances in new computed tomographic (CT) techniques with radiation dose reduction, there are limited studies describing radiation dose parameters to allow routine use of cardiac CT in infants and children with APVR. This study compares cardiac CT findings with intraoperative findings and describes comprehensive radiation exposure parameters.

METHODS

A retrospective analysis of 27 patients compared MDCTA and intraoperative or cardiac catheterization findings of the pulmonary venous anatomy.

RESULTS

A total of 32 MDCTA studies were performed on these 27 patients. Of the 28 studies with subsequent intervention, MDCTA accurately diagnosed the anomalous pulmonary venous anatomy in 27 (96.4%) patients. Narrowing of the pulmonary venous confluence entrance to the coronary sinus was missed on cardiac CT in one patient due to motion artifact, but it was noted intraoperatively. Median estimated effective radiation dose was 0.98 mSv (range: 0.39-3.2 mSv), and mean estimated effective radiation dose was 1.1 ± 0.68 mSv. Median total dose length product (DLP) was 25 mGy cm (range: 10-83 mGy cm), and mean total DLP was 28 ± 18 mGy cm. Median CTDI volume was 3.8 mGy (range: 2.5-14.6 mGy), and mean CTDI volume was 5.0 ± 3.2 mGy.

CONCLUSIONS

We conclude that modern cardiac MDCTA is the best imaging modality to guide management in both preintervention and postintervention APVR patients. In this study, we describe comprehensive radiation exposure parameters in infants and children with APVR.

Optimal timing of contrast-enhanced three-dimensional magnetic resonance left atrial angiography before pulmonary vein ablation

BACKGROUND

To achieve high image quality of cardiovascular magnetic resonance (CMR) pulmonary vein (PV) angiography prior catheter ablation in patients with atrial fibrillation, optimal timing of the angiographic sequence during contrast agent passage is important. The present study identified influential cardiovascular parameters for prediction of contrast agent travel time.

METHODS

One hundred six consecutive patients underwent a CMR examination including three-dimensional (3D) contrast-enhanced PV angiography with real-time bolus tracking prior to catheter ablation. Correct scan timing was characterized by relative signal enhancement measurements in the pulmonary artery, left atrium (LA), and ascending aorta. Furthermore, left- and right-ventricular function, left- and right-atrial dimensions, presence of mitral or tricuspid insufficiencies, and main pulmonary artery diameter were determined.

RESULTS

The highest relative signal enhancement in LA demonstrated optimal scan timing. Contrast agent travel time showed wide variability (range: 12-42 s; mean: 18 ± 4 s). On univariate analysis, most cardiovascular parameters correlated with contrast agent travel time while on multivariate analysis left- and right-ventricular function remained the only independent predictors, but overall a poor fit to the data (adjusted R2, 27.5%) was found.

CONCLUSIONS

Contrast agent travel time was mainly influenced by left- and right-ventricular function but prediction models poorly fitted the data. Thus, 3D PV angiography prior to PV ablation procedures necessitates real-time assessment, with visual determination of individual contrast agent passage time to ensure consistently high CMR image quality.

Non-neoplastic pathology at the crossroads between neck imaging and cardiothoracic imaging

The thoracic inlet is located at the crossroads between imaging of the neck and chest. It represents an important anatomic landmark, serving as the central conducting pathway for many vital structures extending from the neck into the chest and vice versa. Many important body systems are located within this region, including the enteric, respiratory, vascular, lymphatic, neurologic, and endocrine systems. A detailed examination of this region is essential when reviewing neck and thoracic imaging. This article will discuss the normal anatomic boundaries of the thoracic inlet and present an image-rich systematic discussion of the non-neoplastic pathology that can occur in this region. The neoplastic pathology of the thoracic inlet will be covered in a companion article.

Feasibility of 3D black-blood variable refocusing angle fast spin echo cardiovascular magnetic resonance for visualization of the whole heart and great vessels in congenital heart disease

BACKGROUND

Volumetric black-blood cardiovascular magnetic resonance (CMR) has been hampered by long scan times and flow sensitivity. The purpose of this study was to assess the feasibility of black-blood, electrocardiogram (ECG)-triggered and respiratory-navigated 3D fast spin echo (3D FSE) for the visualization of the whole heart and great vessels.

METHODS

The implemented 3D FSE technique used slice-selective excitation and non-selective refocusing pulses with variable flip angles to achieve constant echo signal for tissue with T1 (880 ms) and T2 (40 ms) similar to the vessel wall. Ten healthy subjects and 21 patients with congenital heart disease (CHD) underwent 3D FSE and conventional 3D balanced steady-state free precession (bSSFP). The sequences were compared in terms of ability to perform segmental assessment, local signal-to-noise ratio (SNRl) and local contrast-to-noise ratio (CNRl).

RESULTS

In both healthy subjects and patients with CHD, 3D FSE showed superior pulmonary vein but inferior coronary artery origin visualisation compared to 3D bSFFP. However, in patients with CHD the combination of 3D bSSFP and 3D FSE whole-heart imaging improves the success rate of cardiac morphological diagnosis to 100% compared to either technique in isolation (3D FSE, 23.8% success rate, 3D bSSFP, 5% success rate). In the healthy subjects SNRl for 3D bSSFP was greater than for 3D FSE (30.1 ± 7.3 vs 20.9 ± 5.3; P = 0.002) whereas the CNRl was comparable (17.3 ± 5.6 vs 17.4 ± 4.9; P = 0.91) between the two scans.

CONCLUSIONS

The feasibility of 3D FSE for whole-heart black-blood CMR imaging has been demonstrated. Due to their high success rate for segmental assessment, the combination of 3D bSSFP and 3D FSE may be an attractive alternative to gadolinium contrast enhanced morphological CMR in patients with CHD.

Next-generation sequencing identifies novel genes with rare variants in total anomalous pulmonary venous connection

Background

Total anomalous pulmonary venous connection (TAPVC) is recognized as a rare congenital heart defect (CHD). With a high mortality rate of approximately 80%, the survival rate and outcomes of TAPVC patients are not satisfactory. However, the genetic aetiology and mechanism of TAPVC remain elusive. This study aimed to investigate the underlying genomic risks of TAPVC through next-generation sequencing (NGS).

Methods

Rare variants were identified through whole exome sequencing (WES) of 78 sporadic TAPVC cases and 100 healthy controls using Fisher's exact test and gene-based burden test. We then detected candidate gene expression patterns in cells, pulmonary vein tissues, and embryos. Finally, we validated these genes using target sequencing (TS) in another 100 TAPVC cases.

Findings

We identified 42 rare variants of 7 genes (CLTCL1, CST3, GXYLT1, HMGA2, SNAI1, VAV2, ZDHHC8) in TAPVC cases compared with controls. These genes were highly expressed in human umbilical vein endothelial cells (HUVECs), mouse pulmonary veins and human embryonic hearts. mRNA levels of these genes in human pulmonary vein samples were significantly different between cases and controls. Through network analysis and expression patterns in zebrafish embryos, we revealed that SNAI1, HMGA2 and VAV2 are the most important genes for TAPVC.

Interpretation

Our study identifies novel candidate genes potentially related to TAPVC and elucidates the possible molecular pathogenesis of this rare congenital birth defect. Furthermore, SNAI1, HMGA2 and VAV2 are novel TAPVC candidate genes that have not been reported previously in either humans or animals.

Fund

National Natural Science Foundation of China.

Pictorial review of the pulmonary vasculature: from arteries to veins

Pathology of the pulmonary vasculature involves an impressive array of both congenital and acquired conditions. While some of these disorders are benign, disruption of the pulmonary vasculature is often incompatible with life, making these conditions critical to identify on imaging. Many reviews of pulmonary vascular pathology approach the pulmonary arteries, pulmonary veins and bronchial arteries as individual topics. The goal of this review is to provide an integrated overview of the high-yield features of all major disorders of the pulmonary vasculature. This approach provides a more cohesive and comprehensive conceptualisation of respiratory pathology. In this review, we present both the salient clinical and imaging features of congenital and acquired disorders of the pulmonary vasculature, to assist the radiologist in identifying pathology and forming a robust differential diagnosis tailored to the presenting patient. TEACHING POINTS: • Abnormalities of the pulmonary vasculature are both congenital and acquired. • Pathology of a single pulmonary vascular territory often affects the entire pulmonary vasculature. • Anomalous pulmonary venous flow is named as a function of its location and severity. • Bronchial arteries often undergo dilatation secondary to cardio-respiratory pathology.

Accuracy of echocardiography in diagnosing total anomalous pulmonary venous return

Objective:

Total anomalous pulmonary venous return is an uncommon cyanotic congenital heart defect. Echocardiography is the initial diagnostic tool. Complimentary non-invasive modalities like cardiac computerized tomographic angiography and cardiac magnetic resonance imaging have replaced the need for cardiac catheterization in difficult cases. This study aimed to determine the accuracy of echocardiography in diagnosing total anomalous pulmonary venous return, and to determine the factors that may decrease its sensitivity.

Methods:

This was a cross-sectional study conducted at the Aga Khan University Hospital Karachi, Pakistan from January 2010 to August 2016. All patients who were diagnosed with Total anomalous pulmonary venous return on echocardiography and had subsequent confirmation either on cardiac CT angiography or surgery were included. The diagnostic accuracy of echocardiography was expressed as sensitivity. Previously described taxonomy was used to define diagnostic error. Univariate and multivariate analysis were done by logistic regression OR (95% CI) were reported to identify factors causing the diagnostic error.

Results:

High diagnostic sensitivity (81%) was found in isolated total anomalous pulmonary venous return and low (27%) in heterotaxy and mixed (20%) varieties. Poor acoustic windows and right isomerism were found to be significant factors responsible for the diagnostic error on multivariate analysis.

Conclusion:

Echocardiography can diagnose isolated total anomalous pulmonary venous return with high accuracy. Use of additional modalities may be required for a complete diagnosis in cases with mixed variety, heterotaxy and poor acoustic windows.

Beating the odds: a rare case of supracardiac total anomalous pulmonary venous return (TAPVR) in an adult patient

Total anomalous pulmonary venous return (TAPVR) is a rare congenital heart defect, and patients are usually symptomatic at a very young age. Survival to adulthood without surgical correction is extremely rare. We report a 33-year-old woman with a heart murmur and a history of a successful pregnancy. Echocardiogram revealed a large atrial septal defect with suspicious pulmonary vein anomaly. Chest radiograph demonstrated classical 'snowman' configuration. Cardiac catheterisation was consistent with anomalous pulmonary venous drainage. Cardiac CT confirmed supracardiac TAPVR, whereby all the pulmonary veins drain into the anomalous vein and finally to the superior vena cava. She remained asymptomatic and underwent a successful surgical repair.

A rare variant of intracardiac total anomalous pulmonary venous connection

Total anomalous pulmonary venous connection (TAPVC) with direct connection of the pulmonary veins to the morphologically right atrium is exceedingly rare other than in the setting of isomerism of the right atrial appendages. We present an interesting case of TAPVC in a patient with situs solitus that connected to the right atrium via a broad-mouthed common chamber.

Low-Dose Computed Tomographic Imaging of Partial Anomalous Pulmonary Venous Connection in Children

Background:

In this study, we aimed to determine lobar distribution, drainage sites, and associated cardiovascular anomalies of partial anomalous pulmonary venous connection in pediatric patients using low-dose multidetector computed tomographic angiography.

Methods:

Sixty-one cases (27 female, mean age: 4.7 years) with partial anomalous pulmonary venous connection diagnosed by multidetector computed tomographic angiography were included in this study. In all patients, multidetector computed tomographic angiography examinations were performed using dual-source 256-slice scanner without sedation.

Results:

In 61 patients, 73 anomalous pulmonary veins were detected, 56 (77%) of them were right-sided and 17 (23%) were left-sided. Of 56 right-sided anomalous pulmonary veins in 49 patients, 38 (68%) drained into superior vena cava, eight (14%) into atriocaval junction, six (11%) into inferior vena cava, three (5%) into right atrium, and one (2%) into levoatriocardinal vein. Of 17 left-sided anomalous pulmonary veins in 12 patients, 16 (94%) drained into left innominate vein, and one (6%) into coronary sinus. Only seven (12%) patients had isolated partial anomalous pulmonary venous connection, whereas 54 (88%) patients had additional cardiovascular anomalies. The most common (66%) associated anomaly is atrial septal defect. The overall mean effective radiation dose was 1.12 mSv (range: 0.15-7.41 mSv), and it was 0.58 mSv (range: 0.15-0.73) in the patients younger than one-year old.

Conclusions:

The presence and course of the anomalous pulmonary veins and associated cardiovascular anomalies can be reliably detected by dual-source 256-slice multidetector computed tomographic angiography with low radiation doses.

Total Anomalous Pulmonary Venous Connection in Children: Preoperative Evaluation with Low-Dose Multidetector Computed Tomographic Angiography

We report the results of our retrospective evaluation, from February 2011 through August 2014, of the anatomic features of total anomalous pulmonary venous connection (TAPVC) and its associated cardiovascular anomalies in a pediatric population. In all 43 patients under study (23 female; average age, 9 mo [range, 4 d-7.1 yr]), these examinations had been performed with a dual-source 256-detector scanner. The type of TAPVC, the presence of obstruction, and the association with other cardiovascular anomalies were investigated and recorded. In accordance with the absence or presence of these accompanying anomalies, patients were subdivided into 2 groups: isolated and complex. In the 43 patients, 22 (51%) TAPVCs were supracardiac, 10 (23%) were cardiac, 6 (14%) were infracardiac, and 5 (12%) were mixed. Obstruction was detected in 7 patients. Seventeen patients were in the isolated group and 26 in the complex group. The diagnostic agreements between multidetector computed tomographic angiographic and surgical results were 100% in both the isolated and complex groups. The overall average effective radiation dose was 0.66 mSv (range, 0.15-1.11 mSv); and it was 0.52 mSv (range, 0.12-0.72 mSv) in patients younger than 1 year of age. We conclude that computed tomographic angiography with a dual-source 256-slice multidetector scanner is a reliable imaging method that enables, despite lower radiation doses, the detailed and comprehensive anatomic imaging of TAPVC in neonates and children.

Infracardiac type total anomalous pulmonary venous return with obstruction and dilatation of portal vein

Total anomalous pulmonary venous return (TAPVR), also known as total anomalous pulmonary venous connection, is a congenital cardiovascular malformation that presents itself in the neonatal period, with cyanosis and tachypnea. There are 4 types of TAPVR with the mixed type being the least common. Any type of TAPVR may be associated with obstruction as result of flow redirection through the liver parenchyma before it may return to the heart, but infracardiac is the most common one.

We report a case of a 10-hour-old female, with a mixed (cardiac and infracardiac) TAVPR with obstruction, that showed drainage to the coronary sinus and the portal vein, as the other classic findings in TAVPR, made with computed tomography angiography and echocardiogram. The patient was taken to surgical repair, but unfortunately died during the procedure because of multiple complications.

Multidetector Computed Tomographic Angiography Imaging of Congenital Pulmonary Venous Anomalies: A Pictorial Review

Congenital pulmonary venous anomalies are not uncommon that can occur either in isolation or in association with different forms of congenital heart disease. Clinical presentation of these anomalies may vary from the relatively benign single anomalous partial pulmonary venous return to life-threatening critical obstructed total anomalous pulmonary venous return. Accurate delineation of these anomalies and accompanied cardiovascular anomalies are crucial to guide decision making in these patients. Low-dose high-pitch dual-source 256-detector multidetector computed tomographic angiography is a fast and reliable imaging modality allowing comprehensive noninvasive anatomic imaging in neonates and children with congenital pulmonary venous anomalies with lower radiation doses and should be preferred for these patients after transthoracic echocardiography.

Update on the Role of Cardiac Magnetic Resonance Imaging in Congenital Heart Disease

OPINION STATEMENT

Cardiac magnetic resonance imaging (CMR) is an important imaging modality in the evaluation of congenital heart diseases (CHD). CMR has several strengths including good spatial and temporal resolutions, wide field-of-view, and multi-planar imaging capabilities. CMR provides significant advantages for imaging in CHD through its ability to measure function, flow and vessel sizes, create three-dimensional reconstructions, and perform tissue characterization, all in a single imaging study. Thus, CMR is the most comprehensive imaging modality available today for the evaluation of CHD. Newer MRI sequences and post-processing tools will allow further development of quantitative methods of analysis, and opens the door for risk stratification in CHD. CMR also can interface with computer modeling, 3D printing, and other methods of understanding the complex anatomic and physiologic relationships in CHD.

Sequential segmental classification of feline congenital heart disease

Feline congenital heart disease is less commonly encountered in veterinary medicine than acquired feline heart diseases such as cardiomyopathy. Understanding the wide spectrum of congenital cardiovascular disease demands a familiarity with a variety of lesions, occurring both in isolation and in combination, along with an appreciation of complex nomenclature and variable classification schemes. This review begins with an overview of congenital heart disease in the cat, including proposed etiologies and prevalence, examination approaches, and principles of therapy. Specific congenital defects are presented and organized by a sequential segmental classification with respect to their morphologic lesions. Highlights of diagnosis, treatment options, and prognosis are offered. It is hoped that this review will provide a framework for approaching congenital heart disease in the cat, and more broadly in other animal species based on the sequential segmental approach, which represents an adaptation of the common methodology used in children and adults with congenital heart disease.

Left-Sided Upper Partial Anomalous Pulmonary Venous Return through a Curved Vein Joining the Left Brachiocephalic Vein

The evaluation of pulmonary veins during cross-sectional imaging of the chest and the knowledge of their embryology and anatomy are useful for detecting congenital conditions that may be clinically significant. Moreover, with the spread of cross-sectional imaging it is very frequent to find anatomical variants; therefore the radiologist should easily recognize their appearances. This case report shows a left-side upper partial anomalous pulmonary venous return (PAPVR) through a “curved” vein that joins the left brachiocephalic vein, in a female patient who underwent whole-body computed tomography (CT) for staging endometrial cancer. This was an incidental finding, not related to any symptoms; however, we explain the anatomical aspects of this abnormality within the congenital condition of PAPVR and its possible clinical relevance.

Pediatric Chest MR Imaging: Sedation, Techniques, and Extracardiac Vessels

Thoracic MR imaging in the pediatric population provides unique challenges requiring tailored protocols and a practical approach to pediatric issues, such as patient motion and sedation. Concern regarding the use of ionizing radiation in the pediatric population has continued to advance the use of MR imaging despite these challenges. This article provides a practical approach to thoracic vascular MR imaging with special attention paid to pediatric-specific issues such as sedation. Thoracic vascular anatomy and pathology are discussed with an emphasis on protocols that can facilitate accurate diagnosis.

Partial anomalous pulmonary venous connection with suspected pulmonary hypertension in a cat

Partial anomalous pulmonary venous connection has previously been reported in the dog, but never in a cat. A 14-month-old Devon Rex cat was presented for echocardiography to evaluate a heart murmur noticed during a routine examination. The pertinent finding was right-sided cardiomegaly in the absence of an atrial septal defect or tricuspid regurgitation; pulmonary hypertension was suspected. A thoracic computed tomographic angiography study identified a partial anomalous pulmonary venous connection with the lobar veins of the left caudal, right middle, right caudal and accessory lung lobes draining into the caudal vena cava. The resultant volume overload is an easily overlooked differential diagnosis for right-sided cardiac enlargement. This is the first such report of this anomaly in a cat.

Improved quantification and mapping of anomalous pulmonary venous flow with four-dimensional phase-contrast MRI and interactive streamline rendering

BACKGROUND

Cardiac MRI is routinely performed for quantification of shunt flow in patients with anomalous pulmonary veins, but can be technically-challenging to perform. Four-dimensional phase-contrast (4D-PC) MRI has potential to simplify this exam. We sought to determine whether 4D-PC may be a viable clinical alternative to conventional 2D phase-contrast MR imaging.

METHODS

With institutional review board approval and HIPAA-compliance, we retrospectively identified all patients with anomalous pulmonary veins who underwent cardiac MRI at either 1.5 Tesla (T) or 3T with parallel-imaging compressed-sensing (PI-CS) 4D-PC between April, 2011 and October, 2013. A total of 15 exams were included (10 male, 5 female). Algorithms for interactive streamline visualization were developed and integrated into in-house software. Blood flow was measured at the valves, pulmonary arteries and veins, cavae, and any associated shunts. Pulmonary veins were mapped to their receiving atrial chamber with streamlines. The intraobserver, interobserver, internal consistency of flow measurements, and consistency with conventional MRI were then evaluated with Pearson correlation and Bland-Altman analysis.

RESULTS

Triplicate measurements of blood flow from 4D-PC were highly consistent, particularly at the aortic and pulmonary valves (cv 2-3%). Flow measurements were reproducible by a second observer (ρ = 0.986-0.999). Direct measurements of shunt volume from anomalous veins and intracardiac shunts matched indirect estimates from the outflow valves (ρ = 0.966). Measurements of shunt fraction using 4D-PC using any approach were more consistent with ventricular volumetric displacements than conventional 2D-PC (ρ = 0.972-0.991 versus 0.929).

CONCLUSION

Shunt flow may be reliably quantified with 4D-PC MRI, either indirectly or with detailed delineation of flow from multiple shunts. The 4D-PC may be a more accurate alternative to conventional MRI.

Developmental lung malformations in children: recent advances in imaging techniques, classification system, and imaging findings

Congenital lung anomalies represent a diverse group of developmental malformations of the lung parenchyma, arterial supply, and venous drainage, which may present anywhere from the prenatal period through adulthood. It is imperative for radiologists to be aware of imaging techniques and imaging appearance of these anomalies across the pediatric age range. This review presents the spectrum of these lesions that are often encountered in daily clinical practice. Each anomaly is discussed in terms of underlying etiology, clinical presentation, and imaging characterization with emphasis on the most up-to-date research and treatment. Knowledge of these areas is essential for accurate, timely diagnosis, which aids in optimizing patient outcomes.

Application of prospective ECG-gated high-pitch 128-slice dual-source CT angiography in the diagnosis of congenital extracardiac vascular anomalies in infants and children

PURPOSE

To investigate the value of prospective ECG-gated high-pitch 128-slice dual-source CT (DSCT) angiography in the diagnosis of congenital extracardiac vascular anomalies in infants and children in comparison with transthoracic echocardiography (TTE).

METHODS

Eighty consecutive infants or children clinically diagnosed of congenital heart disease and suspected with extracardiac vascular anomaly were enrolled, and 75 patients were finally included in this prospective study. All patients underwent prospective ECG-gated high-pitch DSCT angiography after TTE with an interval of 1-7 days. The diagnostic accuracy and sensitivity of high-pitch DSCT angiography and TTE were compared according to the surgical/CCA findings. The image quality of DSCT was assessed using a five-point scale. The effective radiation dose (ED) was calculated.

RESULTS

A total of 17 congenital heart diseases and 162 separate extracardiac vascular anomalies were confirmed by surgical/CCA findings in 75 patients. The diagnostic accuracy of high-pitch DSCT angiography and TTE was 99.67% and 97.89%, respectively. The sensitivity of high-pitch DSCT angiography and TTE was 97.53% and 79.62%, respectively. There was significant difference regarding to the diagnostic accuracy and the sensitivity between high-pitch DSCT angiography and TTE (χ2 = 23.561 and 28.013, P<0.05). The agreement on the image quality scoring of DSCT between the two observers was excellent (κ = 0.81), and the mean score of image quality was 4.1±0.7. The mean ED of DSCT was 0.29±0.08 mSv.

CONCLUSIONS

Prospective ECG-gated high-pitch 128-slice DSCT angiography with low radiation dose and high diagnostic accuracy has higher sensitivity compared to TTE in the detection of congenital extracardiac vascular anomalies in infants and children.