Michael Weidenbach

Simulation of congenital heart defects: a novel way of training in echocardiography

Background: Echocardiography is one of the most important diagnostic imaging modalities in paediatric cardiology. Owing to the large number of lesions, achieving expertise often requires years of training. Echocardiography is still taught using the apprenticeship model, which is time- and personnel consuming. Objectives: To extend the echocardiography simulator EchoCom to enable simulation of congenital heart lesions and validate it for training in paediatric echocardiography. Methods: The simulator consists of a life-size manikin, a dummy transducer with attached three-dimensional (3D) tracking system and a computer application. Transthoracic real-time (RT) 3D echocardiographic datasets were collected and embedded into the simulator. Two-dimensional images were calculated and resliced from these datasets according to the position of the tracking sensor. Ten RT 3D datasets of congenital heart lesions were selected for validation. Datasets were blinded and without additional information presented to 43 participants who were stratified according to their expertise (12 experts, 16 intermediates, 15 beginners). Participants were asked to list the relevant findings and make a diagnosis. Construct validation was tested comparing diagnostic performance for each group. Face and content validation were tested using a standardised questionnaire. Results: Participants judged the simulator as realistic and useful. The main drawback was the adult size of the manikin. The diagnostic performance of each group differed significantly proving construct validity. Conclusions: According to this validation the prototype simulator could make a significant contribution to training in the use of echocardiography in congenital heart disease.

Catheter interventional treatment of Sano shunt obstruction in patients following modified Norwood palliation for hypoplastic left heart syndrome.

Shunts placed between the right ventricle and the pulmonary arteries, called Sano shunts, recently modified Norwood surgery for hypoplastic left heart syndrome. Patients with Sano shunts tend to be more stable thus reducing the interstage mortality of this still challenging complex cardiac anomaly. However, Sano shunt stenosis may develop and is a life threatening complication. We report on our experience in patients with Sano shunt obstruction.PatientsEight infants presenting with decreasing transcutaneous oxygen saturations (43–63%, median 58%) following modified Norwood procedures were shown to have relevant Sano shunt stenosis. None was suited for early stage two surgery (cavopulmonary Glenn anastomosis). Catheterization was performed at the age of 21 to 112 (median 85) days. Weight was 3.9 to 6.0 (median 4.8) kg.TechniqueFemoral 5F venous access. Long sheaths were not used. The shunt was entered with a 4F right Judkins catheter and a selective angiography was performed. The stenosis was localized proximal in 5, distal in 1 and proximal and distal in 2 patients. Ten coronary stents were implanted.ResultsThere were no procedure related complications. Oxygen saturation increased immediately to 75–86% (median 80%) and remained above 70% during follow-up in all. Seven patients had successful stage two surgery 61–288 (median 134) days after stent implantation, one is awaiting this.ConclusionsSano shunt obstruction can be treated safely and effectively by stent implantation. Early in-stent restenosis does not seem to be a problem.

Effectiveness of simulator-based echocardiography training of noncardiologists in congenital heart diseases.

Congenital heart diseases (CHD) are responsible for substantial morbidity and mortality in neonates. The preliminary diagnosis often is made by noncardiologists. For this reason, there is a huge demand of training in echocardiography of CHD. This is difficult to achieve due to limited resources of specialized centers.

Giant Cell Myocarditis Mimicking Idiopathic Fascicular Ventricular Tachycardia

We report an adolescent with giant cell myocarditis (GCM) mimicking tachycardia-induced cardiomyopathy. His electrocardiogram (ECG) was typical for an incessant form of fascicular ventricular tachycardia. The patient rapidly deteriorated and required support using extracorporeal membrane oxygenation (ECMO). Biopsy revealed GCM with massive myocyte necrosis. He was successfully heart transplanted 6 days after admission.

Oral Everolimus for Treatment of a Giant Left Ventricular Rhabdomyoma in a Neonate-Rapid Tumor Regression Documented by Real Time 3D Echocardiography.

The presented case reports on successful treatment with everolimus in a neonate with left ventricular giant rhabdomyoma. The authors used a different dosage regime compared to literature and documented rapid tumor regression by 3D echocardiography.

Hypoplastic left heart syndrome with intact atrial septum : Attempt of an interventional palliation by ductal and interatrial stent implantation

SummaryIn patients with hypoplastic left heart syndrome (HLHS) and intact atrial septum, the blood entering the left atrium cannot egress. Emergency treatment interventionally or surgically is mandatory immediately after birth. We describe a patient with HLHS and intact atrial septum who underwent successful transvenous atrial septostomy immediately after birth. When the interatrial communication became restrictive, stent implantation into the arterial duct and into the atrial septum was performed on the 7th day of life. Despite good hemodymanic response, the lung damage was severe and persistent, rendering staged surgical correction impossible. The child died on the 23rd day of life. Autopsy showed patent and correct placed stents in the duct and the atrial septum. There was severe dilatation of pulmonary lymphatic and venous vessels, suggestive of long–standing pulmonary venous hypertension. In conclusion, this form of HLHS has a poor prognosis despite early and aggressive interventional treatment.

The blue child - amiodarone-induced blue-gray skin syndrome and pulmonary mass in a child.

Adverse effects of amiodarone are rarely seen in pediatric patients, but may occur if amiodarone is applied for long‐term treatment. Two rather rare phenomena are blue‐gray skin pigmentation and pulmonary mass. They represent important differential diagnoses from more common clinical complications like pneumonia and drug‐induced toxic skin lesions.

Smart nature. Aortico-left ventricular tunnel bypassing congenital critical aortic stenosis.

Case: A neonate was transferred to our unit because of a 3/6 systolic-diastolic heart murmur. The patient was asymptomatic with normal vital signs. Echocardiography (GE Vivid 7 and Echo Pac PC. version 7.1.1, GE Vingmed Ultrasound A/S, Horten, Norway) revealed a dysplastic and severely stenotic aortic valve. The ALVT consisted of an aneurysmatic, extracardiac component measuring 1.3 9 1.8 cm, with an aortic insertion of the tunnel just above the right coronary sinus. (Figs. 1–3 and movie clip S1) The ascending aorta was significantly dilated and the left ventricle was mildly enlarged without endocardial fibroelastosis. The child underwent successful Ross operation and resection of the ALVT on the 9th day of life and was discharged 14 days thereafter. The 6-month follow-up showed normal left ventricular (LV) function and no AS.

Interruption of the Ascending Aorta: A Hitherto Undescribed Lesion

We are describing a most unusual variant of aortic arch interruption. The ascending aorta was atretic above the sinutubular junction forming a blind-ending pouch. The coronary arteries were the only vessels arising from the aortic trunk. All the brachiocephalic vessels were perfused in retrograde fashion through the arterial duct. The aortic valve itself was dysplastic, stenotic, and permitted severe regurgitation. There was no subaortic obstruction. A modified first stage Norwood palliation was performed. Due to myocardial insufficiency transthoracic extracorporeal membrane oxygenation had to be commenced at the end of surgery. Unfortunately the child died due to severe intracranial hemorrhage.

Intracardiac thrombus causing systemic embolism in a child with idiopathic ventricular tachycardia and heterozygous activated protein C resistance

Abstract:  Systemic embolism in childhood is rare but often disastrous. Most often the concomitant occurrence of more than one prothrombotic factor is responsible for the acute event. We report on a child in whom an intracardiac thrombus embolized into the descending aorta resulting in subtotal occlusion. Causative for thrombus formation was an idiopathic ventricular tachycardia and a heterozygous activated protein C resistance, both previously unknown. Immediate surgical thrombectomy was successful without sequelae. Antithrombotic and antiarrhythmispioproptylactic treatment was started afterwards. We suggest that in cases of longstanding or repeated tachycardia and in children after thromboembolic events diagnostic work‐up for thrombophilia should be undertaken.