Catheter conversion of classic Glenn to bidirectional Glenn with closure of left central shunt years after surgical attempts.

Bidirectional Glenn shunt is usually performed in patients with single ventricle in preparation for a total cavo-pulmonary connection. We present a patient born with complex congenital heart disease consisting of single ventricle, pulmonary atresia, non confluent pulmonary arteries, and anomalous pulmonary venous return in whom surgical bidirectional Glenn was attempted. After multiple surgical attempts she was converted to a Classic Glenn and a central ascending aorta to left pulmonary artery shunt. Several years later by the aid of radiofrequency wire the occluded pulmonary artery segment was canalized establishing continuity between the two pulmonary artery branches with stenting of the intervening segment. The central shunt to the left pulmonary artery was subsequently embolized. Thus this patient was converted in the catheterization laboratory from the physiology of a classic Glenn to the more preferred bidirectional Glenn physiology.

Closure of external tunnel Fontan fenestration: a novel use of the Amplatzer vascular plug.

BACKGROUND: Newer modifications of the Fontan operation include the external tunnel conduit with placement of an elongated type of fenestration. Atrial septal defect closure devices used traditionally to close fenestrations have short connecting waists with retention discs on each side. These may not be suitable for this type of Fontan fenestration. The length of the fenestration may not allow proper expansion of the retention discs on these devices. The Amplatzer vascular plug, a new occlusion device without a centering waist or retention discs designed to close vascular malformation, can be placed entirely within an elongated tube or vessel. METHODS: A retrospective review was used to study patients who underwent catheter closure of Fontan fenestration in our institution. Only patients whose procedure was performed after the commercial release of the Amplatzer vascular plug were included in the study. RESULTS: The vascular plug was implanted in 4 of 10 patients who underwent fenestration closure. The plug was successfully placed in all four patients without protrusion into either the systemic or pulmonary venous side of the baffle. There were no incidences of embolization, hemolysis, or infective endocarditis. All the patients experienced significant improvement in oxygen saturation. The technical aspects of this device are discussed as well as its safe and effective use. The satisfactory follow-up evaluation also is reported. CONCLUSIONS: This study outlines a novel use of the Amplatzer vascular plug for successful closure of selected Fontan fenestrations.

Transhepatic closure of atrial septal defect and assisted closure of modified Blalock/Taussig shunt.

The details of transhepatic closure of moderate - large size atrial septal defect as well as assisted closure of a modified Blalock Taussig shunt in a 2 1/2 year old patient with occluded femoral vessels are discussed. The technical variations as well as the potential advantages of this route are outlined.

Catheter management of occluded superior baffle after atrial switch procedures for transposition of great vessels.

We present successful catheter intervention in 4 patients with total occlusion of the superior baffle after an atrial switch procedure. A transseptal needle (in addition to the transhepatic route in 1 patient with known occluded femoral veins) was used to open the occluded segments and place stents. Additionally, we report the regression of multiple systemic-to-pulmonary venous fistulas that developed as a result of the occluded baffle.

Catheter closure of accessory pulmonary blood flow after bidirectional Glenn anastomosis using Amplatzer duct occluder.

Additional source of pulmonary blood flow in patients with bidirectional cavopulmonary anastomosis (Glenn shunt) may cause elevation of the pulmonary artery pressure precluding safe completion of the Fontan operation. A case is presented with single-ventricle bidirectional cavopulmonary anastomosis and additional flow from the ventricle to the pulmonary artery resulting in elevated Glenn pressure. The communication was successfully occluded using Amplatzer duct occluder with satisfactory reduction in the Glenn pressure.

The evaluation and management of syncope in children

Syncope or reversible loss of consciousness is common in children, experienced by about 20 percent of the paediatric population at least once, and accounts for about 6 percent of hospital admissions. The evaluation of these patients may be expensive and unrewarding. Their symptom complex arouse extremes anxiety, for the most part unwarranted, in family, friends, teachers and physicians, resulting in restriction in activity. The most common cause of syncope in this population is neurally medicated, a benign condition which can often be easily treated by reassurance, situational avoidance and simple medication to augment cardiac output and/or to blunt the responsible neural reflex. Occasionally, syncope may be a manifestation of a serious or life threatening cardiac disorder, which requires more in depth evaluation and treatment to reduce the symptoms and the risk of sudden death. A stepwise approach to evaluation can categorize these patients to avoid unnecessary expense and anxiety while at the same time recognising the more serious cardiac disorders. A careful history of the episodes, family history and physical examination, together with a 12 lead electrocardiogram, may be all that is necessary to evaluate a simple faint. With more complex symptoms, especially with recurrence, a head up tilt examination is useful. More detailed evaluation can be reserved for those for whom there is a high index of suspicion based on their previous results. This common sense approach to the evaluation of syncope could allay anxiety and reduce physical activity restrictions and costs in an already economically exhausted care system.(AU)

Supraventricular tachycardia: recent advances in children

Supraventricular tachycardia (SVT) is the most common arrhythmia in children, occurring in about 1/1000 live births. Symptoms may begin in utero or early infancy when there is a significant risk of death. In older children symptoms vary from mild to severely debilitating with a small risk for sudden death in patients with Wolfe-Parkinson-White Syndrome. A better understanding of pathophysiology and cellular mechanisms provided the basis of the new therapeutic strategies. New classes of antiarrhythmic drugs, both for acute termination of SVT (eg. adenosine) and control of recurrence (eg. amiodarone and flecainide), added to older medications such as digoxin and propranolol, resulted in better control in both fetus and child. The greatest innovation in therapy, however, is electrical mapping of atrio-ventricular bypass tracts and their permanent interruption by radio frequency energy catheter ablation. This form of therapy provides a complete cure with 95 percent success and a 1 percent risk for complications in older children and adults. The risk is significantly higher in infants. A thorough knowledge of cardiac anatomy, electrophysiology and natural history is necessary to select appropriate therapy for individual patients to achieve maximum efficacy with minimum complications.(AU)