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Notes: Zusammenfassung Der operative Verschluß eines Vorhofseptumdefekts (ASD) kann heutzutage ohne präoperative Katheteruntersuchung durchgeführt werden. Für den interventionellen Verschluß unter Durchleuchtung ist jedoch eine Strahlenexposition unvermeidbar. Wir berichten über einen interventionellen ASD-Verschluß allein unter transösophagealer Ultraschallkontrolle. Ein neun Jahre altes Mädchen mit einem 11 mm großen ASD vom Secundum-Typ wurde zum interventionellen ASD-Verschluß vorgestellt. Das Shuntvolumen über den Defekt wurde Doppler-echokardiographisch mit Qp/Qs=1,7:1 und oxymetrisch mit Qp/Qs=1,6:1 bestimmt. Unter Sedierung mit Midazolam und Propofol wurde sowohl die Katheterdiagnostik als auch die Intervention ohne Durchleuchtung durchgeführt. Die Defektgröße wurde unter transösophagealer Echokardiographie mit einem 5F Ballonkatheter ermittelt: Der Defekt war 11 mm groß, der Abstand zu den rechten Lungenvenen betrug 10 mm, zum Koronarsinus und zur Mitralklappe jeweils 8 mm. Unter transösophagealer Echokardiographie konnte komplikationslos ein 11 mm großer Amplatzer Septal Occluder in den Defekt plaziert werden. Es bestand kein Restshunt. Der hier berichtete Fall demonstriert, daß die Technik des interventionellen ASD-Verschlusses inzwischen so ausgereift ist, daß sowohl Diagnostik, Sizing als auch Implantation eines transvenös eingebrachten Amplatzer Septal Occluders ganz ohne Röntgenstrahlung möglich ist.

Notes: BOOK REVIEWS

Notes: BOOK REVIEWS

Notes: Summary Over the last few years, various devices for the interventional closure of atrial septal defects (ASD) up to a diameter of 20mm have been developed. We report our clinical experience in closing ASD with a diameter larger than 20mm diameter with the Amplatzer Septal Occluder (ASO).¶   Method: The stretched diameter of the ASD was measured by inflating a sizing balloon within the defect until an indentation in the circumference in the balloon could be observed. An ASO with a stent diameter 2–4mm larger than the indentation in the circumference of the balloon was chosen and implanted via 9–12 French sheaths. In contrast to the closure of smaller defects, pullback of the device onto the atrial septum was only performed when the connecting stent of the ASO was completely deployed in order to achieve maximal centering characteristics and optimal support of the retention skirt of the left atrial disc on the edges of the defect. Only then was the right atrial disc deployed and actively configured by advancing the sheath and the delivery cable against the atrial septum. Implantation was only attempted if the atrial septal rims (except the anterior rim around the aorta) measured more than 7mm by echocardiography to avoid injury or disturbance of sensitive intracardiac structures. After placement, the fixation of the device and the mechanical stability was proven by an extensive “Minnesota wiggle”. The ASO was released only when TEE showed no or a trivial residual color flow through the connecting stent; otherwise repositioning was performed.¶   Results: Out of 352 patients (P) with successful closure of interatrial defects, 70 P (age: 1.1–77.3 years) had stretched defects larger than 20mm diameter (median 22mm diameter (20–36), 25/75% quartiles=20/26mm). Mean shunt size was Qp:Qs 2.1:1 (0.7–3.9:1), mean fluoroscopy time 10.9min (0–63). Complete closure could be achieved in 85.7/93.1/100% after 3 months, ¶1 and 2 years, respectively. Besides 3P with persistent atrial fibrillation, only 5 P showed transient atrial tachyarrhythmias, 2 only periprocedural and 3 within the first 3months after implantation were treated with β-blocker. In one patient, an acute embolization of the device occurred because a diminished posterior rim was not visualized by a monoplane TEE probe necessitating surgical explantation and defect occlusion. Despite oversizing the device, no “mushrooming” misconfiguration were observed.¶   Conclusion: Transcatheter closure of large atrial septal defects with the Amplatzer Septal Occluder is feasible, safe and effective. Risk of complications do not seem to occur more frequently than after closure of smaller defects if one adheres to certain sizing and implantation measures. The incidence of transient atrial tachyarrhythmias seems to be low.

Notes: Summary Background: Pediatricians and neonatologists are still reluctant to consider invasive cardiological or cardiosurgical treatment in low body weight infants because it is believed to considerably increase the risk. The aim of this study was to assess the results and complications of percutaneous transcatheter interventions in infants with a weight below 2.5 kilograms. ¶   Methods: Retrospective analysis was undertaken for all patients with a weight below 2.5 kilograms who underwent cardiac catheterization from 01/1994 to 04/1999. During this time 42 diagnostic catheterizations in 29 patients and 27 transcatheter interventions in 24 patients were performed. ¶   Results: Surgery was replaced or effectively postponed in 9 (33%) out of 27 transcatheter interventions. This was possible for pulmonary stenosis, valvular aortic stenosis and aortic coarctation. A stabilization of the hemodynamic situation was possible in 14 patients. An antegrade pulmonary flow was established in 5, an effective interatrial shunt created in 5 and the arterial duct stented in 3 patients. Only 3 patients had no benefit from the intervention; however, there were no deaths nor hemodynamic complications. Arrhythmias occurred in 9% of all catheterizations and interventions but were transient in all cases. Femoral arterial complications were observed in 30% of all arterial catheterizations. ¶   Conclusion: Diagnostic cardiac catheterization and percutaneous transcatheter interventions can be performed with low mortality and acceptable morbidity in low weight infants. Transcatheter interventions can replace surgery, postpone the necessity for surgery or stabilize the hemodynamic situation prior to surgery.

Notes: Summary In recent years many different systems for transcatheter closure of an atrial septal defect (ASD) have been developed and tested. However, all systems presently available have some special disadvantages. The recently introduced Amplatzer Septal Occluder (ASO), though, appears promising. It is a self-expanding and self-centering double disc made from a Nitinol mesh, which is tightly woven to give mechanical strength. Both discs are separated by a connecting cylindrical portion. Its diameter may be chosen, so that it corresponds to that of the ASD. Discs of polyester patches are sewn into the retention discs as well as into the cylindrical portion of the device in order to augment thrombogenicity. After measuring the diameter of the ASD with a balloon, an appropriate ASO is selected and advanced into the left atrium through a 7 or 8 French sheath. Then the distal disc and part of the connecting cylindrical portion is developed in the left atrium and pulled against the atrium septum, so that the cylindrical portion is occluding the ASD. Thereafter, proximal disc is deployed and the delivery cable disconnected. As long as the cable is connected to the device repositioning is easily achieved by pulling the device back into the sheath. Within a time period of 4 month in 29 out of 31 patients (median age: 12.1 years, median weight: 45.0 kg) complete closure of the ASD with a mean diameter of 11.0 mm (6–20 mm) was achieved without complications, the average fluoroscopy time being 8.3 min (2.9–21.5 min). Mean Qp:Qs was 1.5 (0.9–2.2). During a mean follow-up period of 2.1 months post implantation fixed seating of the ASO without residual shunt, arrhythmias, thrombembolic events and impairment of A–V valves was observed in all patients. Conclusion: The Amplatzer septal occluder allows quick, safe and complete closure of atrial septal defects without complications if one adheres to strict implantation criteria. For a final judgement, however, long-term follow-up studies are necessary.