John B. Mawson

Pediatric primary benign cardiac tumors: A 15-year review

An increase in the incidence of primary cardiac tumors has been reported since the development or enhancement of noninvasive imaging modalities. We identified 56 children with primary cardiac tumors. Forty-four (78%) children had rhabdomyomas, 6 (11%) fibromas, 1 (2%) pericardial teratoma, 1 (2%) epicardial lipoma, 1 (2%) multicystic hamartoma, and 3 (5%) unspecified tumors. The mean age at diagnosis was 19 +/- 35 months (median 4.7 months, range 0.03 to 204 months), excluding 12 patients who were given the diagnosis before birth. Among 27,640 patients assessed for cardiac disease, the incidence of tumors was 0.06% (1980 to 1984), 0.22% (1985 to 1989), and 0.32% (1990 to 1995). Diagnosis was made in 55 of 56 patients by echocardiography. Catheterization was performed in five patients and magnetic resonance imaging in nine. No tumor-related deaths occurred. Nine patients had surgery because of hemodynamically significant obstruction or arrhythmias. Partial or complete regression occurred in 24 (54%) of 44 patients with rhabdomyomas. Overall, the prognosis was excellent. Individualized surgery allowed early safe treatment of symptomatic tumors.

MR imaging of arrhythmogenic right ventricular cardiomyopathy: Morphologic findings and interobserver reliability

Background: Magnetic resonance (MR) imaging is frequently used to diagnose arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D). However, the reliability of various MR imaging features for diagnosing ARVC/D is unknown. The purpose of this study was to determine which morphologic MR imaging features have the greatest interobserver reliability for diagnosing ARVC/D. Methods: Forty-five sets of films of cardiac MR images were sent to 8 radiologists and 5 cardiologists with experience in this field. There were 7 cases of definite ARVC/D as defined by the Task Force criteria. Six cases were controls. The remaining 32 cases had MR imaging because of clinical suspicion of ARVC/D. Readers evaluated the images for the presence of (a) right ventricle (RV) enlargement, (b) RV abnormal morphology, (c) left ventricle enlargement, (d) presence of high T1 signal (fat) in the myocardium, and (e) location of high T1 signal (fat) on a Likert scale with formatted responses. Results: Readers indicated that the Task Force ARVC/D cases had significantly more (χ2 = 119.93, d.f. = 10, p < 0.0001) RV chamber size enlargement (58%) than either the suspected ARVC/D (12%) or no ARVC/D (14%) cases. When readers reported the RV chamber size as enlarged they were significantly more likely to report the case as ARVC/D present (χ2= 33.98, d.f. = 1, p < 0.0001). When readers reported the morphology as abnormal they were more likely to diagnose the case as ARVC/D present (χ2 = 78.4, d.f. = 1, p < 0.0001), and the Task Force ARVC/D (47%) cases received significantly more abnormal reports than either suspected ARVC/D (20%) or non-ARVC/D (15%) cases. There was no significant difference between patient groups in the reported presence of high signal intensity (fat) in the RV (χ2 = 0.9, d.f. = 2, p > 0.05). Conclusions: Reviewers found that the size and shape of abnormalities in the RV are key MR imaging discriminates of ARVD. Subsequent protocol development and multicenter trials need to address these parameters. Essential steps in improving accuracy and reducing variability include a standardized acquisition protocol and standardized analysis with dynamic cine review of regional RV function and quantification of RV and left ventricle volumes.

Fluoroscopic landmark for SVC-RA junction for central venous catheter placement in children.

Background. Vascular access devices are commonly placed under image guidance. The usual aim is to place the tip at the superior vena cava-right atrial juntion (SVC-RA).¶Objective. To identify a radiographic landmark for the SVC-RA junction that would be useful for accurate central venous catheter tip placement in children.¶Materials and methods. Images from 56 children undergoing contrast studies of their upper limb venous systems were examined for location of the SVC-RA in relation to a radiographic landmark.¶Results. Most patients (92.5 %) showed the SVC-RA junction to lie at the sixth thoracic vertebral level or the interspace above or below. The SVC-RA junction lay lower than the right main bronchus and the notch on the right cardiomediastinal contour.¶Conclusion. The vertebral body provides a useful and radiographically visible landmark for accurate central catheter tip placement.

Utilization of ultrasound for the detection of pneumothorax in the neonatal special-care nursery

Pneumothorax is a potentially life-threatening condition in the setting of the neonatal special-care nursery (SCN) that may result in rapid deterioration and death. The familiar appearances associated with pneumothorax on AP supine chest radiograph are highly specific, but limited in sensitivity. In this case report, we describe the theory and technique of thoracic ultrasound for detection of pneumothorax in the SCN, providing a viable alternative to the cross-table lateral radiograph without ionising radiation, with highly accurate results, and with minimal patient positioning.

Repair in infancy of right aortic arch with aberrant left brachiocephalic artery in the setting of a variant of the hypoplastic left heart syndrome.

A right aortic arch, with a retroesophageal transverse arch and an aberrant left brachiocephalic artery, is a rare anomaly by itself. When combined with severe mitral stenosis and hypoplasia of the left ventricle, it is rarer still. We describe the diagnosis and treatment of this rare anomaly in an infant using a modification of the Norwood operation.

Interrupted right aortic arch and origin of the left pulmonary artery from the aorta in DiGeorge syndrome.

We describe a neonate with DiGeorge syndrome undergoing diagnosis and successful repair of interrupted right aortic arch and origin of the left pulmonary artery from the aorta. We discuss a link between this lesion and persistence of a left fifth arch.

Coronary Arteriovenous Fistula: Direct Connection of the Proximal Circumflex Artery to the Coronary Sinus

There exists an extensive literature describing the clinical and morphologic characteristics of coronary artery fistulas [1, 2]. The angiographic and echocardiographic appearances of the two cases in the reports that follow highlight the confusion in the current literature with regard to differentiating coronary arteriovenous fistulas and the entity known as the aorto-right atrial tunnel [3, 4]. The aorto-right atrial tunnel is a very rare anatomic condition in which the communication arises directly from the aorta, with dilation of the corresponding sinus of Valsalva [4]. The ‘‘tunnel’’ consists of a dilated and tortuous vessel originating from either the left, or noncoronary, sinus with variable entry to the right atrium. The coronary arteries arise independently of the aorto-right atrial tunnel, and no branching vessels (coronary artery) arise from the tunnel itself. Two-dimensional echo cardiography can differentiate a coronary arteriovenous fistula by visualizing both coronary origins separately away from the tunnel. They manifest as a dilated main coronary artery with proximal and distal branches that distribute into the myocardium [4, 5]. The sinus of Valsalva has normal morphology.

Imaging of a Carotid Aneurysm in Two Patients Following Extracorporeal Membrane Oxygenation Therapy

Following extracorporeal membrane oxygenation (ECMO), two patients subsequently developed carotid aneurysms at the site of cannulation. Given the invasive nature of ECMO, vascular ultrasound and/or computerized tomographic imaging should be considered to rule out cannulation-site complications post-ECMO.

Diagnosis of Van den Ende-Gupta syndrome: Approach to the Marden-Walker-like spectrum of disorders.

Marden–Walker syndrome is challenging to diagnose, as there is significant overlap with other multi‐system congenital contracture syndromes including Beals congenital contractural arachnodactyly, D4ST1‐Deficient Ehlers–Danlos syndrome (adducted thumb‐clubfoot syndrome), Schwartz–Jampel syndrome, Freeman–Sheldon syndrome, Cerebro‐oculo‐facio‐skeletal syndrome, and Van den Ende–Gupta syndrome. We discuss this differential diagnosis in the context of a boy from a consanguineous union with Van den Ende–Gupta syndrome, a diagnosis initially confused by the atypical presence of intellectual disability. SNP microarray and whole exome sequencing identified a homozygous frameshift mutation (p.L870V) in SCARF2 and predicted damaging mutations in several genes, most notably DGCR2 (p.P75L) and NCAM2 (p.S147G), both possible candidates for this childs intellectual disability. We review distinguishing features for each Marden–Walker‐like syndrome and propose a clinical algorithm for diagnosis among this spectrum of disorders.