Accuracy of Cardiac Magnetic Resonance Imaging in Diagnosing Pediatric Cardiac Masses: A Multicenter Study.

BACKGROUND: After diagnosis of a cardiac mass, clinicians must weigh the benefits and risks of ascertaining a tissue diagnosis. Limited data are available on the accuracy of previously developed noninvasive pediatric cardiac magnetic resonance (CMR)-based diagnostic criteria. OBJECTIVES: The goals of this study were to: 1) evaluate the CMR characteristics of pediatric cardiac masses from a large international cohort; 2) test the accuracy of previously developed CMR-based diagnostic criteria; and 3) expand diagnostic criteria using new information. METHODS: CMR studies (children 0-18 years of age) with confirmatory histological and/or genetic diagnosis were analyzed by 2 reviewers, without knowledge of prior diagnosis. Diagnostic accuracy was graded as: 1) single correct diagnosis; 2) correct diagnosis among a differential; or 3) incorrect diagnosis. RESULTS: Of 213 cases, 174 (82%) had diagnoses that were represented in the previously published diagnostic criteria. In 70% of 174 cases, both reviewers achieved a single correct diagnosis (94% of fibromas, 71% of rhabdomyomas, and 50% of myxomas). When ≤2 differential diagnoses were included, both reviewers reached a correct diagnosis in 86% of cases. Of 29 malignant tumors, both reviewers indicated malignancy as a single diagnosis in 52% of cases. Including ≤2 differential diagnoses, both reviewers indicated malignancy in 83% of cases. Of 6 CMR sequences examined, acquisition of first-pass perfusion and late gadolinium enhancement were independently associated with a higher likelihood of a single correct diagnosis. CONCLUSIONS: CMR of cardiac masses in children leads to an accurate diagnosis in most cases. A comprehensive imaging protocol is associated with higher diagnostic accuracy.

Aorto-Right Ventricular Tunnel: An Uncommon Problem with a Common Solution.

Aorto-ventricular tunnel is a rare congenital malformation, and aorto-right ventricular tunnel (ARVT) is an even less common entity. Here, we report the case of a 3-month-old female who underwent successful surgical closure of ARVT. The origin of the right coronary artery was proximal to the ostium of the tunnel.

Right ventricular myxoma in a patient with tetralogy of Fallot.

INTRODUCTION: Cardiac myxoma is the most common primary cardiac tumour in adulthood and may present in the context of Carney's complex. PRESENTATION OF CASE: A 32-year-old male with a history of repaired tetralogy of Fallot in childhood was admitted with severe pulmonary valve regurgitation and a mobile mass in the right ventricle. The patient underwent pulmonary valve replacement and mass excision. Pathology examination showed myxoma. DISCUSSION: In the majority of cases myxomas originate in the atria, nevertheless they can also be found in a ventricular cavity. Myxoma is a prevalent feature of Carney's complex, an inherited, autosomal disease, characterised by multiple tumours in several organs. Tetralogy of Fallot has also been described in association with Carney's complex. CONCLUSION: Coexistence of tetralogy of Fallot with a cardiac ventricular myxoma in a patient not affected from Carney's complex or other familial syndrome.

Saw-tooth cardiomyopathy.

We present an unusual case of cardiomyopathy in a two month old male infant with a grade-I systolic murmur. Echocardiographic examination disclosed left ventricular (LV), dysplasia with saw-tooth like inwards myocardial projections extending from the lateral walls towards the LV cavity. There was mild LV systolic dysfunction with apical hypokinesia. Cardiovascular magnetic resonance demonstrated in detail these cross bridging muscular projections originating from the inferior interventricular septum and lateral LV wall, along with areas of hypokinesis at the LV septum and apex in a noncoronary distribution, without any late gadolinium enhancement. We have termed this condition saw-tooth cardiomyopathy because of the very characteristic appearance.

Fatal cardiac arrest due to an unusual fibroma of the pulmonary valve.

Fibroma, the second most common tumor in childhood, usually is a large solitary mass involving the ventricular septum or the left and rarely the right free ventricular wall. An unusual case of a 5.2-year-old boy with a large mass originating from the pulmonary valve is reported. The patient presented for evaluation of a murmur. Echocardiography and cardiac magnetic resonance imaging showed a large tumor extending from the distal right ventricular outflow tract through the pulmonary valve and into the main pulmonary artery causing moderate obstruction. The patient had a fatal cardiac arrest while awaiting surgery. The postmortem examination proved the tumor to be a fibroma.

Transcatheter closure of coronary arterial fistulas using the new Amplatzer vascular plug.

We report our initial experience in using the Amplatzer vascular plug for closure of coronary arterial fistulas. The self-expanding, cylindrical, device is made from Nitinol wire mesh, and is available from 4 to 16 millimetres in diameter. We have now used the device to close fistulas in 3 patients, aged from 3 to 14 years, who presented with ratios of pulmonary-to-systemic flow from 1.5 to 3. In 2 patients, fistulas arising from the proximal right and left coronary arteries, with maximal diameters of 9 and 10 millimetres, respectively, had their narrowest diameter, of 6 millimetres, proximal to the entrance into the right atrium via a saccular aneurysm. The third fistula, with a maximal diameter of 16 millimetres, and with its origin from the circumflex coronary artery, entered the right atrium with nearly unrestricted flow, its narrowest diameter being 8 millimetres. For interventional closure, we chose plugs twice the diameter of the narrowest segment of the fistula, thus using 2 devices of 12 millimetres and one of 16 millimetres diameter. An arteriovenous loop was established through the fistula by snaring an exchange guide wire. Using a 7 or 8 French guide catheter inserted through the femoral vein, all plugs were placed at the narrowest segment of the fistula, leading to immediate complete closure of 2 fistulas. The third patient, with a fistula of the circumflex coronary artery, who received the largest plug initially had residual flow, but the fistula was found to be completely occluded at 12 months follow-up examination. We have demonstrated, therefore, safe and effective usage of the new vascular plug for transcatheter closure of moderate- to large-sized coronary arterial fistulas. The plug offers an alternative to cardiac surgery, or occlusion using coils.

Nonfluoroscopic catheter navigation for radiofrequency catheter ablation of supraventricular tachycardia in children.

BACKGROUND: Radiofrequency catheter ablation (RCA) of supraventricular tachycardia (SVT) in children is highly successful but requires exposure to radiation. Nonfluoroscopic mapping systems may significantly reduce fluoroscopy time. METHODS: Forty consecutive pediatric patients who underwent RCA for accessory pathways (AP) or AV nodal reentrant tachycardia (AVNRT) with use of a nonfluoroscopic navigation system (Ensite NavX) (group A) were compared retrospectively to 40 consecutive patients with similar diagnoses who underwent RCA with fluoroscopic guidance only (group B). RESULTS: Group A (mean age 12.1+/-2.9 years, mean weight 47+/-13.9 kg) consisted of 11 patients (27.7%) with AVNRT and 29 (72.5%) with AP. Group B (mean age 10.9+/-3.1 years, mean weight 47.1+/-17.1 kg) consisted of 7 patients (17.5%) with AVNRT and 33 (82.5%) with AP. There were no significant differences in AP location, patients with congenital heart disease, and number of radiofrequency lesions. Fluoroscopy time was significantly shorter in group A than in group B (10.4+/-6.1, range 3.1-28.8 minutes, vs 24.9+/-16.0, range 4.4-82.0 minutes, P<0.0001). Procedure duration was also significantly shorter in group A than in group B (170+/-68.5, range 90-420 minutes, vs 218+/-69.3, range 90-360 minutes, P<0.0001). Initial success was 95% in group A and 100% in group B. Tachycardia recurrences occurred in two patients in group A (5%) and six patients in group B (15%). Final success, including repeat ablations for recurrences or failures, was 100% in both groups. CONCLUSIONS: The use of a nonfluoroscopic system for catheter navigation significantly reduced fluoroscopy exposure and total procedure duration of RCA of common SVT substrates in children.