Cardiac CT or MRI in pediatric practice: Which one to choose?

Image quality and radiation dose of dual source high pitch computed tomography in pediatric congenital heart disease

To explore the image quality and radiation dose of dual source high-pitch cardiac computed tomography with tailored contrast injection protocols for pediatric congenital heart disease patients (CHD). In total, 27 infants with CHD (median age 109 days [IQR 6-199]) were retrospectively analyzed regarding dose length product (DLP) and effective dose (ED) after undergoing cardiothoracic CT imaging. Scan parameters were adjusted on a dual source/detector CT (DSCT) to minimize radiation dose while maintaining adequate quality. Image acquisition was performed at 70% of the R-R interval. Dose reducing measures included prospective electrocardiogram gating, utilizing slow injection velocities and foregoing bolus tracking during contrast injection. Image quality was assessed for artefacts, vessel definition, and noise on a 5-point scale (1 non-diagnostic, 5 excellent). Series were scored on a 0-to-3-point scale regarding answered clinical questions (0 non-diagnostic, 3 all clinical questions could be answered). The median DLP was 5.2 mGy*cm (IQR 3.5-7.8) leading to a median ED of 0.20 mSv (IQR 0.14-0.30). On average the acquired images scored 13.3 ± 2.1 (SD) out of a maximum 15 points with an intraclass correlation coefficient (ICC) of 0.94. All acquired series were able to fully answer all clinical questions scoring maximum points (ICC 1.0). Dual source high pitch CT protocols combined with custom contrast agent injection protocols in pediatric patients with CHD delivered sufficiently high diagnostic imaging quality combined with low submilisievert radiation doses. Prospective high pitch imaging is a reliable method for depiction of cardiac anatomy even in very young pediatric CHD patients with elevated heart rates.

Isolated Coarctation of the Aorta: Current Concepts and Perspectives

Current management of isolated CoA, localized narrowing of the aortic arch in the absence of other congenital heart disease, is a success story with improved prenatal diagnosis, high survival and improved understanding of long-term complication. Isolated CoA has heterogenous presentations, complex etiologic mechanisms, and progressive pathophysiologic changes that influence outcome. End-to-end or extended end-to-end anastomosis are the favored surgical approaches for isolated CoA in infants and transcatheter intervention is favored for children and adults. Primary stent placement is the procedure of choice in larger children and adults. Most adults with treated isolated CoA thrive, have normal daily activities, and undergo successful childbirth. Fetal echocardiography is the cornerstone of prenatal counseling and genetic testing is recommended. Advanced 3D imaging identifies aortic complications and myocardial dysfunction and guides individualized therapies including re-intervention. Adult CHD program enrollment is recommended. Longer follow-up data are needed to determine the frequency and severity of aneurysm formation, myocardial dysfunction, and whether childhood lifestyle modifications reduce late-onset complications.

Utility of cardiac CT in infants with congenital heart disease: Diagnostic performance and impact on management

BACKGROUND

Advances in cardiac CT (CCT) scanner technology allow imaging without anesthesia, and with low radiation dose, making it an attractive technique in infants with congenital heart disease. However, the utility of CCT using a dual-source scanner with respect to diagnostic performance and impact on management has not been systematically studied in this population.

METHODS

Retrospective review of infants who underwent CCT to determine the utility of CCT with respect to the following: answering the primary diagnostic question, providing new diagnostic information, prompting a change in management, and concordance with catheterization or surgical inspection.

RESULTS

A total of 156 infants underwent 172 scans at a median age of 64 days, (IQR 4-188) from Jan 2016-Dec 2019. The most frequent diagnostic question was related to the pulmonary arteries (43%), followed by the aortic arch (30%), pulmonary veins (26%), coronary arteries (17%), patent ductus arteriosus (10%) and others (9%). A high-pitch spiral scan was frequently used (90%). The median effective radiation dose was low (0.66 ​mSv) and general anesthesia was used infrequently (23%). CCT answered the primary diagnostic question in 168/172 (98%) and added to the diagnostic information already available by echocardiography in 161/172 (96%) scans. CCT led to a change in management following 78/172 (53%) scans and had an impact on management following 167/172 (97%) scans. On follow-up, after 107/172 (62%) scans, subjects underwent cardiac surgery, and after 55/172 (32%) scans, they had cardiac catheterization. CCT findings were concordant with catheterization and/or surgical inspection in 156/159 (98%) scans.

CONCLUSIONS

In infants with complex congenital heart disease, CCT was accurate, answered the diagnostic questions in nearly all cases, and frequently added diagnostic information that impacted management. Radiation exposure was low, and anesthesia was needed infrequently.

A Giant Arteriovenous Malformation and Fistula in a Newborn with Parkes Weber Syndrome. Case Report

Parkes Weber syndrome (PWS) is a rare congenital condition characterized by capillary cutaneous malformation, limb hypertrophy and multiple arteriovenous fistulas of the affected extremity. Another feature is a port-wine stain on the affected area. PWS is caused by genetic variations in the RAS p21 protein activator (RASA1) gene which affects the development of the vascular system.

We report a case of a female neonate presenting with dyspnoea and cardiovascular insufficiency at the time of birth.

The left upper extremity (LUE) and shoulder were enlarged (circumference at the midpoint was 17 cm compared to 11 cm on the right arm), edematous, hyperemic with a port-wine stain. Structural changes of the bones of LUE were discovered on X-ray.

Echocardiography revealed right-sided volume overload, a large ductus arteriosus, a possible pathology of the aortic arch and branch arteries. Chest X-rays showed cardiomegaly. Therapy with milrinone and diuretics was started.

A multislice CT angiography scan revealed arteriovenous fistula (AVF) between a. subclavia sin. and v. bra-chiocephalica sin, arteriovenous malformations (AVM) and a dilated a.subclavia sin. of 11 mm, as well as dilatation of other arteries of the LUE. Next generation sequencing revealed a pathogenic variation (c.2245C>T, p.Arg749*) in the RASA1 gene in the heterozygous state.

Four consecutive embolizations of the AVM and AVF were performed in the first 16 months.

Diagnostic Accuracy of Noncontrast Self-navigated Free-breathing MR Angiography versus CT Angiography: A Prospective Study in Pediatric Patients with Suspected Anomalous Coronary Arteries

RATIONALE AND OBJECTIVES

To evaluate the diagnostic accuracy of a prototype noncontrast, free-breathing, self-navigated 3D (SN3D) MR angiography (MRA) technique for the assessment of coronary artery anatomy in children with known or suspected coronary anomalies, using CT angiography (CTA) as the reference standard.

MATERIALS AND METHODS

Twenty-one children (15 male, 12.3 ± 2.6 years) were prospectively enrolled between July 2014 and August 2016 in this IRB-approved, HIPAA-compliant study. Patients underwent same-day unenhanced SN3D-MRA and contrast-enhanced CTA. Two observers rated the visualization of coronary artery segments and diagnostic confidence on a 3-point scale and assessed coronary arteries for anomalous origin, as well as interarterial and intramural course. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of SN3D-MRA for the detection of coronary artery abnormalities were calculated. Interobserver agreement was assessed using Intraclass Correlation Coefficients (ICC).

RESULTS

Fourteen children showed coronary artery abnormalities on CTA. The visualization of coronary segments was rated significantly higher for CTA compared to MRA (p <0.015), except for the left main coronary artery (p = 0.301), with good to excellent interobserver agreement (ICC = 0.62-0.94). Diagnostic confidence was higher for CTA (p = 0.046). Sensitivity, specificity, PPV, and NPV of MRA were 92%, 92%, 96%, and 87% for the detection of coronary artery anomalies, 85%, 85%, 74%, and 92% for high origin, 71%, 92%, 82%, and 87% for interarterial, and 41%, 96%, 87%, and 80% for intramural course.

CONCLUSIONS

Noncontrast SN3D-MRA is highly accurate for the detection of coronary artery anomalies in pediatric patients while diagnostic confidence and coronary artery visualization remain superior with CTA.

Three-dimensional printing models in congenital heart disease education for medical students: a controlled comparative study

BACKGROUND

This study sought to assess, using subjective (self-assessment) and objective (MCQ) methods, the efficacy of using heart models with ventricular septal defect lesions produced with three-dimensional printing technology in a congenital heart disease curriculum for medical students.

METHODS

Three computed tomography datasets of three subtypes of ventricular septal defects (perimembranous, subarterial and muscular, one for each) were obtained and processed for building into and printing out 3D models. Then a total of 63 medical students in one class were randomly allocated to two groups (32 students in the experimental, and 31 the control). The two groups participated in a seminar with or without a 3D heart model, respectively. Assessment of this curriculum was carried out using Likert-type questionnaires as well as an objective multiple choice question test assessing both knowledge acquisition, and structural conceptualization. Open-ended questions were also provided for getting advice and suggestion on 3D model utilization in CHD education.

RESULTS

With these 3D models, feedback shown in the questionnaires from students in experimental group was significantly more positive than their classmates in the control. And the test results also showed a significant difference in structural conceptualization in favor of the experimental group.

CONCLUSION

It is effective to use heart models created using current 3D printing technology for congenital heart disease education. It stimulates students' interest in congenital heart disease and improves the outcomes of medical education.

[Segmental approach to congenital heart diseases: Principles and applications to prenatal imaging]

This pictorial essay will initially present the origin, definitions, objectives and main principles of the segmental approach to congenital heart diseases. Then, through ultrasound scans iconography we will consider its practical applications to prenatal screening. Eventually, through both ultrasound and MRI cases, we will discuss its potential use in fetal diagnostic evaluation.

Multimodality imaging of aortic coarctation: From the fetus to the adolescent

Aortic coarctation is a local narrowing of the aortic lumen, which is located at the level of the isthmus in 95% of patients. Aortic coarctation accounts for 5 to 8% of all congenital heart diseases. It may have an acute presentation in the form of heart failure in the neonate or may be discovered incidentally in adult because of severe treatment-resistant hypertension. Ultrasound may reveal the presence of aortic coarctation during the antenatal period. In this situation, associated abnormalities should be investigated (including karyotype), because they influence prognosis and indicates whether or not the birth should occur in a center with pediatric cardiology expertise. Postnatally, ultrasound and chest radiography are the basic imaging work-up. Computed tomography is often the second line imaging investigation in infants and young children for whom magnetic resonance imaging fails to confirm the diagnosis. Magnetic resonance imaging with cardiac synchronization is the preferred imaging tool in the post-treatment period. Aortic coarctation may be treated surgically or by endovascular techniques. Potential complications should be searched for using ultrasound and magnetic resonance imaging.