Catheter closure of atrial septal defects using the Cocoon septal occluder: preliminary results of a European multicenter study.

Despite its simplicity, device closure of atrial septal defects is still associated with rare but potentially lethal complications. In this prospective non-randomized multicenter study we investigated the safety and efficacy of the Cocoon septal occluder (CSO) for closure of atrial septal defects (ASDs) in 92 patients. Median age of the patients was 10.5 years (range 3-61 years) and median weight was 25 kg (range 13-65 kg). The device is an improved new generation double disc design made of Nitinol wire mesh that is coated with platinum using NanoFusion technology. The discs are connected by a waist with diameter ranging from 6mm to 40 mm with 2mm increments. All patients completed a 3-month follow-up. Mean ASD diameter was 21 ± 7 mm (range 10-35 mm), while the mean device diameter was 24 ± 8 mm (range 14-40 mm). The CSO was permanently implanted in all 92 patients. Complete echocardiographic closure of the defect immediately after the procedure or at the one month follow-up, was observed in all 92 patients (100%). No device-related complications were observed during the procedure or at short-term follow-up (range 3-12 months). Our preliminary results indicate that CSO is a promising device for transcatheter closure of ASDs. Further studies are required to document its efficacy, safety and long-term results in a larger patient population.

Transcatheter closure of large atrial septal defects with deficient aortic or posterior rims using the "Greek maneuver". A multicenter study.

OBJECTIVES: We report a modification ("Greek maneuver") of the standard atrial septal defect (ASD) closure technique using the Amplatzer septal occluder (ASO) to facilitate closure of large ASDs with deficient aortic or posterior rims. METHODS: 185 patients (median 10.8, range 3 to 52 years) with large ASDs (mean diameter 26±7 mm, range 20-40 mm) with a deficient aortic (134 patients) or posterior (51 patients) rim underwent catheter closure with the ASO using the "Greek maneuver" under transesophageal guidance. The Greek maneuver is applied when protrusion of the aortic edge of the deployed left disk of the device in to the right atrium is detected by echo. To circumvent this left disk is recaptured and the whole delivery system is pushed inward and leftward into the left atrium where the left disk and the 2/3 of right disk are simultaneously released. This maneuver forces the left disk to become parallel to the septum preventing the protrusion of the device into the right atrium. RESULTS: The ASO was successfully implanted and was associated with complete closure in 175/185 (95%) of the patients. There were no early or late complications related to the procedure during a follow-up period ranging from 6 months to 7 years. CONCLUSIONS: The "Greek maneuver" is a simple quite useful trick that facilitates closure of large ASDs associated with or without deficient aortic or posterior rims.

Initial and six-year results of stent implantation for aortic coarctation in children.

Although stenting has been used as a treatment option for aortic coarctation (CoA) at increasingly younger ages, limited information is available on the long-term follow-up of stent implantation for CoA in pediatric patients. A total of 74 patients with CoA (mean age 8 ± 3 years) underwent stent implantation; 42 were treated for isolated native CoA and 32 for recurrent CoA. A total of 87 stents were implanted (bare metal stents in 71 patients and covered stents in 3 patients). Redilation of a previously implanted stent was performed in 32 patients. Immediately after stenting, the peak systolic pressure gradient decreased from 68 ± 16 mm Hg to 8 ± 5 mm Hg (p <0.05), and the CoA diameter increased from 5 ± 3 mm to 16 ± 3 mm (p <0.05). The most important procedural complication was aneurysm formation in 1 patient that was successfully treated with implantation of a covered stent. No early or late deaths occurred and no evidence was found of late aneurysm formation during a follow-up period of 6 years. Late stent fracture was observed in 3 patients. At the end of follow-up, no cases of recoarctation were identified on multislice computed tomography or magnetic resonance imaging, and 67 (85%) of the 74 patients were normotensive, receiving no medications. In conclusion, stent implantation is an effective and safe treatment alternative to conventional surgical management for the treatment of CoA in selected pediatric patients.

Usefulness of stenting in aortic coarctation in patients with the Turner syndrome.

We report our experience with stent implantation for treatment of aortic coarctation in patients with Turner syndrome. Ten consecutive patients with Turner syndrome and aortic coarctation (median age 12 years, range 9 to 24) underwent coarctation stenting. Of these, 6 patients were treated for isolated coarctation and 4 for recurrent coarctation (3 after balloon dilation and 1 after balloon dilation and surgical repair). Bare metal stents were implanted in 7 patients and covered stents in 3. Immediately after stent implantation, peak systolic gradient decreased from 46.1 ± 24.3 to 1.9 ± 2.1 mm Hg (p <0.001). Aortic diameter at coarctation site increased from 5.1 ± 3.2 to 15.3 ± 2.0 mm after stenting (p <0.001). There were no deaths or procedure-related complications. During a median follow-up of 30.5 months, no patient developed restenosis. Two patients developed late aortic aneurysms at the coarctation site. In conclusion, stent implantation for aortic coarctation in patients with Turner syndrome appears to be a safe and effective alternative to surgical repair. Larger cohorts and longer-term follow-up are required to determine the effects of the procedure on the aortic wall.

Severe hemolysis complicating transcatheter occlusion of a patent ductus arteriosus: the importance of elimination of residual flow.

Transcatheter closure of a patent ductus arteriosus (PDA) is an established technique that may rarely be complicated by severe intravascular hemolysis due to residual shunt. Although conservative management has been reported, the usual approach is to invasively eliminate the residual shunt. We report a case where misjudgment of PDA size and subsequent attempted closure with only one coil led to incomplete closure and residual shunt, which was complicated by severe intramuscular hemolysis. Effectively closing the PDA with an Amplatzer Duct Occluder resulted in immediate resolution of the hemolysis.

Assessment of patient radiation doses during transcatheter closure of ventricular and atrial septal defects with Amplatzer devices.

The purpose of this study was to estimate the radiation dose to which children are exposed during cardiac catheterizations for the treatment of ventricular and atrial septal defects. Radiation doses were estimated for 46 children aged 1-18 years. These children were treated for secundum atrial septal defects (ASD group) for perimembranous ventricular septal defects (VSD group) or underwent a routine diagnostic catheterization (diagnostic group). Thermoluminescent dosimeters (TLDs) were attached in locations, representing the lateral entrance dose, the posterior entrance dose, the thyroid dose, and the gonad dose, respectively. A dose area product (DAP) meter was also attached externally on the posterior-anterior (PA) tube to give a direct value in cGy cm(2) for each procedure. The patient's entrance dose from the PA field ranged from 1.5 to 185.0 mGy for all patients, while the lateral entrance dose varied from 0.9 to 204 mGy. Radiation exposure to the thyroid and the gonads was found to vary from 0.4 to 8.3 and 0.1 to 2.1 mGy, respectively. The DAP meter recorded DAP values for the posterior tube, between 46 and 3,700 cGy cm(2). The mean effective dose was found to be 7.7, 16.2, and 33.3 mSv for the diagnostic, the ASD, and the VSD group, respectively. Very strong correlation was found between the DAP values and the entrance radiation dose measured with TLDs. The mean entrance dose received from therapeutic cardiac catheterizations using the Amplatzer devices was found approximately twice the dose received from a diagnostic one. Even for the most complex procedures, the maximum entrance dose was at least 10 times lower than the threshold, associated with skin erythema.

Catheter closure of congenital/acquired muscular VSDs and perimembranous VSDs using the Amplatzer devices.

Over the past 10 years a variety of occluding devices has been used for transcatheter closure of ventricular septal defects (VSDs), but none has gained wide acceptance. This article presents the experience of transcatheter closure of muscular and perimembranous VSDs in 22 and 13 patients, respectively, with the new Amplatzer VSD occluders. Overall total occlusion was achieved in 95% and 92.3% of patients with muscular and perimembranous VSDs, respectively. The main complication was embolization of the device in 1/13 (7.6%) patients with perimembranous VSDs. Transcatheter closure of VSDs using the Amplatzer VSD occluders appears to be a safe and effective alternative to the standard surgical treatment.

Initial human experience with the Amplatzer perimembranous ventricular septal occluder device.

Transcatheter closure of perimembranous ventricular septal defects with coils or devices designed to close other lesions may be complicated by embolization or aortic insufficiency. A new asymmetric Amplatzer perimembranous ventricular septal occluder and delivery system was specifically designed for perimembranous defects. This report describes the first use of this device in 27 patients. Implantation was successful in 25 (93%), with 1 removed for device-related aortic insufficiency and inability to position the delivery sheath in another. Device orientation was excellent when the device was initially advanced through a standard delivery sheath positioned in the left ventricular apex. Twenty-three had complete occlusion within 1 week (92%), with a tiny (< 2 mm) residual shunt in the other two. In the 25 subjects with the device left in place, device-related aortic or tricuspid insufficiency, arrhythmias, and embolization were not observed. These excellent acute results need to be confirmed by long-term follow-up.