Balloon valvuloplasty in the treatment of congenital aortic valve stenosis--a retrospective multicenter survey of more than 1000 patients.

BACKGROUND: The value of balloon valvuloplasty of the aortic valve in childhood is still under debate. OBJECTIVE: To evaluate the results of the procedure in a retrospective multicenter survey of a large cohort over a long time interval. METHODS: Retrospective analysis of 1004 patients with balloon valvuloplasty of the aortic valve performed between 9/1985 and 10/2006 at 20 centers in Germany, Austria and Switzerland. Amongst others, the following parameters were evaluated before and after the procedure as well as at the end of follow-up or before surgery: clinical status, left ventricular function, transaortic pressure gradient, degree of aortic regurgitation, freedom from re-intervention or surgery. PATIENTS: Patients from 1 day to 18 years of age with aortic valve stenosis were divided into four groups: 334 newborns (1-28 days); 249 infants (29-365 days); 211 children (1-10 years), and 210 adolescents (10-18 years). RESULTS: Median follow-up was 32 months (0 days to 17.5 years). After dilatation the pressure gradient decreased from 65 (± 24)mm Hg to 26 (± 16)mm Hg and remained stable during follow-up. The newborns were the most affected patients. Approximately 60% of them had clinical symptoms and impaired left ventricular function before intervention. Complication rate was 15% in newborns, 11% in infants and 6% in older children. Independently of age, 50% of all patients were free from surgery 10 years after intervention. CONCLUSIONS: In this retrospective multicenter study, balloon valvuloplasty of the aortic valve has effectively postponed the need for surgery in infants, children and adolescents up to 18 years of age.

A novel implantation technique for closure of an atypical fenestration connecting the right atrial appendage to an extracardiac conduit by use of a 15 mm Helex device in a patient with total cavopulmonary connection.

We report on a 7-years old patient after total cavopulmonary anastomosis with an extracardiac conduit. An atypical fenestration was created during the operation connecting the right atrial appendage to the extracardiac conduit. Because of arterial desaturation, the fenestration connecting the anterior wall of the extracardiac conduit to the posterior wall of the right atrial appendage was successfully occluded with a 15 mm Helex device by use of a modified implantation technique.

Transcatheter PFO closure with a prominent Eustachian valve.

We report the successful PFO closure in a 57-year old woman with complex atrial anatomy. To avoid the risk of interfering with the occluder device due to a prominent Eustachian valve, a Helex Septal Occluder was implanted. Differential therapeutic considerations and specific device characteristics are outlined.

[Case report: neonatal hypertension]. / Kasuistik: neonatale arterielle Hypertonie.

BACKGROUND: Neonatal arterial hypertension is rare with an incidence between 0.2 - 3 %. Clinical presentation varies widely and is in some cases dramatic. PATIENT: A 4-day old full-term neonate was admitted to the intensive care unit with severe congestive heart failure and metabolic acidosis. Mechanical ventilation was initiated and dobutamine administered because of poor systolic function. Continuous monitoring of blood pressure revealed severe arterial hypertension (30 to 40 mm Hg above the 95th percentile). Ultrasonography showed an echogenic left kidney with normal perfusion. Laboratory examinations revealed a raised peripheral renin activity, thrombocytopenia, slightly raised d-dimers, a microhematuria and mild proteinuria. After resolution of hypertension under therapy with an ACE-inhibitor, a MAG3 renal scan showed complete absence of renal function on the left side. Renal artery stenosis was excluded by venous transcardial angiography. Under therapy with Captopril, the patient was discharged and followed up for 8 months. He is developing normally with normal serum creatinine (0.4 mg/dl), but low renal function (17 %) of the left side as assessed by DMSA-scan and compensatory right kidney hypertrophy are observed. DISCUSSION: Diagnosis and treatment of neonatal hypertension are discussed with respect to the proposed case. After exclusion of other causes we conclude that a perinatal microangiopathic event may have lead to the renal lesions with malignant renovascular hypertension.

Permanent pacemaker implantation in a 1,445 g preterm neonate on the first day of life.

Here, we present a case involving a very low-birthweight baby (1445 g) born prematurely after 30 weeks of gestation with congenital complete heart block and low-output failure. The newborn was successfully treated by implantation of an epimyocardial pacemaker on her first day of life.

[Transcatheter closure of atrial septal defects with the CardioSEAL occluder]. / Katheterinterventioneller Verschluss von Vorhofseptum-Defekten mit dem CardioSEAL-Okkluder.

Data on mid- and long-term follow-up for the recent devices for closure of secundum-type atrial septal defects are limited. The purpose of our retrospective study was to report the effectiveness of transcatheter closure in patients with various morphological types of atrial septal defect other than centrally located defects within the oval fossa using the CardioSEAL and CardioSEAL-Starflex occluder. A total of 91 patients (age 1.5-71 years, median 6 years) underwent transcatheter closure. On the transesophageal echocardiogram, defect size varied from 6 to 18 mm with an estimated stretched diameter of 11 to 24 mm, median 15 mm; the ratio of the stretched diameter to septal length ranged from 0.28 to 0.68. Mean follow-up was 28.7 +/- 11,9 months (range 3-46 months). Isolated secundum-type defects were present in 59 patients (65%), multiple septal defects including patients with perforated atrial septal aneurysms and defects with deficient atrial rim in 32 patients (35%). Occlusion rate using device diameters from 23 to 40 mm increased from 66% (60/91 patients) immediately after implantation to 86% (48/56 patients) 24 months after implantation. Patients with isolated secundum-type defects presented with a significantly higher primary closure rate (45/59 patients, 76%) compared to patients with various defect morphology. Closure rate did not depend on the type of implanted device modification. No thrombus formation, sustained atrial arrhythmia or infective endocarditis occurred. Serial transthoracic echocardiographic findings revealed protrusion of one left-sided arm onto the right atrial aspect in 5 patients; malposition of one right-sided superior arm of the device was observed in 7 patients. Fluoroscopy showed single fatigue fracture in 7 patients (7.7%) within the first 6 months after implantation. These results demonstrate that transcatheter closure with the double umbrella device was effective and safe on medium-term follow-up and could be extended to atrial septal defects of various morphology.

[Infantile hemangioendothelioma of the liver--sonographic diagnosis and follow-up]. / Das infantile Hämangioendotheliom der Leber - sonographische Diagnostik und Verlaufskontrolle.

OBJECTIVE: Hepatic haemangioendothelioma is the most frequently observed hepatic tumour of early infancy. Lesions may cause life-threatening disease due to av-shunt-related cardiac failure, Kasabach-Merritt syndrome or encroachment on surrounding tissue. In this paper, the value of ultrasonography at initial work-up as well as during follow-up under various management strategies is discussed. METHOD: Retrospective analysis of sonographic and clinical data as well as outcome of 14 patients. RESULTS: The tumours may present initially with a typical sonographic pattern of a roundish solitary lesion consisting predominantly of massively perfused, tortuous cavities. In these cases, histological verification of the diagnosis is not mandatory, provided serological tumour markers are negative. Multifocal haemangioendotheliomata with a solid appearance, however, cannot be reliably distinguished from other entities sonographically. Tumour development - with or without therapy - can be followed up precisely using repeated ultrasound evaluations of tumour volume and sono-morphology as well as Doppler examination of tumour perfusion. CONCLUSIONS: Guidelines for the management of these patients are discussed, based on our experience and a review of the literature. Sonography proves to be of outstanding importance.

A novel approach to temporary stenting: degradable cardiovascular stents produced from corrodible metal-results 6-18 months after implantation into New Zealand white rabbits.

OBJECTIVE: To determine whether corrodible materials may be safely used as biodegradable cardiovascular implants. DESIGN: Corrodible iron stents (> 99.8% iron) were produced from pure iron and laser cut with a stent design similar to a commercially available permanent stent (PUVA-AS16). A total of 16 NOR-I stents were implanted into the native descending aorta of 16 New Zealand white rabbits (mean luminal diameter at the implantation site 3.4 mm, balloon diameter to vessel diameter ratio 1.13). RESULTS: No thromboembolic complications and no adverse events occurred during the follow up of 6-18 months. All stents were patent at repeat angiography after 6 (n = 9), 12 (n = 5), and 18 months (n = 2) with no significant neointimal proliferation, no pronounced inflammatory response, and no systemic toxicity. CONCLUSIONS: This initial in vivo experience suggests that degradable iron stents can be safely implanted without significant obstruction of the stented vessel caused by inflammation, neointimal proliferation, or thrombotic events.

[A new combined surgical interventional method for univentricular palliation of congenital heart defects]. / Eine neue kombinierte chirurgisch-interventionelle Methode zur univentrikulären Palliation angeborener Herzfehler.

UNLABELLED: Total cavo-pulmonary anastomosis is frequently performed to palliate patients with a broad variety of congenital heart defects with functionally univentricular hearts precluding biventricular circulation. In patients with risk factors for primary repair a stepwise approach is frequently chosen with initial creation of an aorto-pulmonary shunt followed by a Glenn anastomosis or hemifontan procedure. Finally a total cavo-pulmonary connection is completed surgically. The aim of this feasibility study was to develop a combined surgical-interventional approach for creation of a total cavo-pulmonary anastomosis which reduces the number of surgical interventions, precludes extracorporeal circulation and intracardiac sutures, putting the patients at risk for subsequent rhythm disturbances. METHODS: A Glenn anastomosis was created in 10 sheep without cardio-pulmonary bypass. The superior vena cava was banded superior to the cavo-atrial junction leaving a minimal lumen for subsequent interventional balloon dilatation and implantation of a stent graft. A 15 mm Gore-Tex tube was sutured around the inferior vena cava intrapericardially to provide resistance for subsequent interventional stent implantation. Total cavo-pulmonary anastomosis was completed interventionally by dilating the banded vena cava superior and connection of the inferior vena cava to the superior vena cava by implanting an Aneurx covered stent graft. RESULTS: All animals survived the combined surgical-interventional procedure. Stent deployment was possible without causing obstruction to the hepatic veins. Neither stent dislocation nor rhythm disturbances were encountered. CONCLUSIONS: Total cavo-pulmonary anastomosis can be achieved without intracardiac sutures and cardio-pulmonary bypass by use of a combined surgical-interventional approach using the Aneurx covered stent graft.

Transcatheter recanalization of the left main pulmonary artery after four years of complete occlusion.

A technique for transcatheter "reconstruction" of a completely occluded left pulmonary artery using radiofrequency perforation with subsequent balloon dilation and stent implantation is reported in a 7-year-old child. It is shown that transcatheter radiofrequency perforation can still be effective years after the occlusion of a vessel.

Abbreviated combined anatomical/electrophysiological approach for catheter ablation of atrioventricular nodal reentrant tachycardia in children.

Atrioventricular nodal reentrant tachycardia was proven during electrophysiologic study in 41 children, aged from 3.7 to 16 years, who were referred for catheter ablation of symptomatic supraventricular tachycardia. Using an abbreviated combined anatomical and electrogram-guided approach for selective ablation of the slow pathway, a steerable ablation catheter was placed at the inferior region of the vestibule of the tricuspid valve close to the orifice of the coronary sinus, with the intention of recording a multicomponent local atrial electrogramm during sinus rhythm. If application of radiofrequency current of 500 kHz at 70 degrees C at this site did not result in a slowly accelerated junctional rhythm, at a rate of less than 120 beats per minute, the catheter was stepwise advanced up to a position midway towards the apex of the triangle of Koch for additional applications of energy. Ablation was achieved in 35 of the patients. In 6 patients, the slow pathway was modulated such that the tachycardia could no longer be induced. The number of applications of energy ranged from 1 to 19, with a median of 6 applications. The mean period of fluoroscopy was reduced to 15.6 (4.3 to 39.8) minutes, while the overall duration of the catheterization procedures ranged from 88 to 280 (mean 173.2) minutes. In none of the patients did we observe permanent high grade atrioventricular block. During follow-up over a mean of 4.1 years, two patients had recurrence of tachycardia, corresponding to a 95% rate of success in the midterm. We conclude that selective radiofrequency ablation of the slow pathway using the abbreviated anatomical and electrophysiological approach is a safe and curative therapeutic approach in children with atrioventricular nodal reentrant tachycardia. Periods required for fluoroscopy can be significantly reduced, and mid-term results are excellent.

Transcatheter closure of various types of defects within the oval fossa using the double umbrella device (CardioSEAL)--feasibility and echocardiographic follow-up.

Data on long-term follow-up for closure of so-called secundum type" atrial septal defects within the oval fossa using recently developed devices are limited, and results focused on presence of residual shunting. The purpose of our study was to report the experience from a single center establishing the effectiveness of transcatheter closure in patients with various types of defect other than those located centrally within the oval fossa. A total of 72 patients was included in this study. On transesophageal echocardiography, the size of the defects varied from 6 to 18 mm, with estimation of the stretched diameter from 11 to 21 mm. The ratio of stretched diameter to the extent of the residual septum ranged from 0.28 to 0.54. Mean follow-up was 30.5+7.4 months, with a range from 13 to 42 months. The rate of closure using devices with diameters from 28 to 40 mm increased from 80% immediately after implantation to 93% in the 57 patients examined 24 months after implantation. For further analysis, we compared the 44 patients with a solitary, centrally located, defect to 28 having morphological variations, including superiorly located defects with deficient superior and aortic rims, multifenestrated and aneurysmal defects, or isolated additional defects. There was no incidence of formation of thrombus, sustained atrial arrhythmia, or infective endocarditis. Residual shunting was not influenced by location or morphology of the defects, but increased with size, stretched diameter, and the ratio of pulmonary to systemic flows. Serial transthoracic echocardiographic findings revealed malposition of one right-sided superior arm of the device in 8 patients, while protrusion of one left-sided arm onto the right atrial aspect was observed in 3 patients. Fluoroscopy showed fatigue fracture of a single arm in 7 patients (9.7%) within the first 6 months after implantation. These results demonstrate that transcatheter closure with the non self-centering double umbrella device was effective and safe on medium-term follow-up, and could be extended to defects within the oval fossa having various morphologies. Residual shunting resolved with time, and was not related to either morphology or the position of the device.

Coronary artery stenosis after radiofrequency catheter ablation of accessory atrioventricular pathways in children with Ebstein's malformation.

BACKGROUND: Complications concerning the coronary arteries that are directly related to radiofrequency catheter ablation procedures have not been reported in children. Coronary artery lesions, however, have been demonstrated after the endocardial application of radiofrequency current in young animals. METHODS AND RESULTS: Two boys with Ebstein's anomaly of the tricuspid valve developed clinically asymptomatic coronary artery stenosis after radiofrequency catheter ablation of right-sided accessory atrioventricular pathways with standard catheter technology. CONCLUSIONS: The complication of coronary artery stenosis demonstrates a substantial risk after right atrial free wall radiofrequency current application in children. The risk of late coronary alterations should be considered when the use of catheter ablation procedures to young patients is proposed.

Endovascular stenting as an emergency treatment for neonatal coarctation.

We describe a neonate with critical coarctation of the aorta. Since treatment with Prostaglandin E1 had failed to reopen the arterial duct, and surgery was deemed to be associated with an unacceptably high risk in this unstable neonate, it was decided to perform balloon dilation of the coarctation as a palliative procedure to stabilize the patient. Balloon angioplasty failed to reduce the pressure gradient across the coarctation, so a stent was implanted retrogradely as an emergency procedure. Subsequently, the stented segment was resected surgically and end-to-end anastomosis created without complications at seven months of age.

A novel method for transcatheter closure of atrial septal defect within an aneurysm of the fossa ovalis: double sheath technique.

An aneurysm of the fossa ovalis is frequently associated with an atrial septal defect. Intervention with transcatheter closure of such defects may be difficult since it bears the risk of inadvertent deployment of the device with both umbrellas in the right or left atrium. A novel technique for the closure of such multiperforated aneurysms of the fossa ovalis, which allows central positioning and controlled deployment of the device, is reported.

Transcatheter retrieval and repositioning of an Amplatzer device embolized into the left atrium.

A transcatheter technique is described for stabilization and retrieval of an embolized Amplatzer device, which was inadvertently deployed in the left atrium of a 2-year-old girl with hemodynamically significant atrial septal defect within the fossa ovalis. Since surgery was not available for immediate device retrieval, transcatheter means were chosen to prevent embolization of the device into the mitral valve. After stabilizing the device by creating a guidewire circuit through the wire mesh of the right atrial disk, the Amplatzer device was repositioned through the interatrial defect by snaring the microscrew. No residual shunting and perfect device position was recorded during Doppler echocardiography directly after the procedure as well as 1, 2, and 120 days after the intervention. Cathet. Cardiovasc. Intervent. 51:297-300, 2000.