Atrial septal defect with deficient aortic (antero-superior) rim. Ao – aorta; ASD – atrial septal defect; LA – left atrium; RA – right atrium. 

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... widespread [6]. In the Latvian Centre of Cardiology first percutaneous transcatheter closure of an ASD was performed in 2002 [7]. The Amplatzer septal occluder (ASO) is one of the most versatile and practical devices to use. It is capable of closing defects up to 40 mm in diameter via a relatively low-profile delivery sheath. More importantly, the ASO may be easily withdrawn into the sheath after deployment but prior to release, which is essential in safely closing dif- ficult defects where successful positioning on the initial deployment is not guaranteed. The Amplatzer septal occluder (AGA Medical Corporation, Golden Valley, MN, USA) is a percutaneous, transcatheter, atrial septal defect closure device intended for the occlusion of atrial septal defects in the secundum position (Figure 1). It is a self-expandable, double disc device made from a nickel–titanium (Nitinol wire mesh). The two discs are linked together by a short connecting waist. In order to increase its closing ability, the discs and the waist are filled with polyester fabric. The polyester fabric is securely sewn to each disc by a polyester thread. The device is screwed onto the delivery cable and is delivered through the preformed sheath sized between 6 and 12 F, depending of the size of the device. The devices range in size (measured by central waist diameter) from 4 to 40 mm. The left atrial disc overhangs the waist by 6–8 mm and the right atrial disc – by 4–5 mm depending on the device size. These flanges grip the septum and provide the stability. From February 2002 to November 2005 percutaneous transcatheter ASD closure with an Amplatzer septal occluder was attempted in 42 patients (34 female (80%)) in our centre. The mean age was 41.7 ± 18.8 years (range 1–68 y). The youngest patient was a 1-year-old girl, the oldest – a 68-year-old female patient. The mean weight was 71.4 ± 22.9 kg (range 9–125 kg). One of the patients was a pregnant woman with progressive symptomatic heart failure during pregnancy (20 weeks of pregnancy). Two patients had 2 defects. All patients had 1 or more following indi- cations for the closure: symptomatic heart failure, clinical evidence of right ventricular volume overload (i.e., right ventricular dilatation and/or ratio of pulmonary to systemic flow Qp/Qs of 1.5 or more estimated by Doppler echocardiography), recurrent supraventricular arrhythmias (mostly atrial fibrillation). In 41 adults and adolescents percutaneous ASD closure was performed under local anesthesia and in one small child under general anesthesia using transesophageal echocardiography (TEE) in 34 (81%) patients or transthoracic echocardiography (TTE) in 8 (19%) patients for guidance in cardiac catheterization laboratory. The mean defect diameter measured with tran- soesophageal echocardiography was 16.7 ± 6.4 mm (range 6–30 mm). The mean stretched diameter with a sizing balloon was 23.5 ± 7.0 mm (range 10–34) mm. The mean device size implanted was 25 ± 8 mm (range 10–40 mm). In all patients 1 device was implanted (including 2 patients with 2 defects, which were covered with 1 ASO). Prior to closure all patients with the ASD (with the exception in a small child) were evaluated for suitability for percutaneous closure by TEE. Patients were given heparin 100 IU/kg, cefa- zolin 1.0 i/v for endocarditis prophylaxis and se- dation with midazolam 2.5–5 mg i/v. In a small child the procedure was performed under general anesthesia. Following percutaneous puncture of the right femoral vein catheterization of the left atrium with a multipurpose catheter was performed. The multipurpose catheter in the left atrium was replaced with a 0.35 J-tipped stiff guidewire, the tip of which was preferably located in the left upper pulmonary vein (in some cases – the right upper pulmonary vein). Using an AMPLATZER Sizing Balloon specifi- cally designed for sizing atrial defects the stretched diameter of an ASD was estimated. The ASO device equal or slightly greater (1–2 mm) as the stretched diameter was chosen. If there were deficient antero-superior rims, device greater than 2–4 mm was chosen. The deployment of the device was performed under fluoroscopic and echocardiographic con- trol. Through the delivery sheath the device was delivered into the left atrium and the left atrial disk and the central waist portion was opened. Then both the device and the sheath were withdrawn to the septum as a unit, and once the resis- tance of the septum was encountered, the sheath was further withdrawn to allow the right atrial disk to open fully in the right atrium. Once the ASO has been fully opened, it is important to confirm by TEE or TTE that both atrial disks are flattened and the left atrial disk is entirely in the left atrium and the right atrial disk is entirely in the right atrium. Importantly, there should be no interference to mitral valve function or any ob- struction to caval or pulmonary venous flow. In cases when there is a small or deficient aortic rim (Figure 2), two disks should be gently splayed around the aorta rather than having both disks pointing at the aorta (Figure 3). This requirement is necessary to avoid the possibility of subacute perforation of the aorta. There is usually a small amount of colour flow through the centre of the device, which may persist for a few days until the mesh within the device clots off. A small amount of shunting at the edge of the device is accept- able, particularly in large defects, since this usually completely close over the next few weeks or months as endothelization of and fibrosis around the device occurs [6]. After the procedure the delivery sheath is re- moved immediately and a patient takes bedrest for 6–8 hours. On the next day a chest X-ray and echocardioscopy is performed in all patients. The discharge was on the next 1–2 days. Mean hospital stay was 3 ± 2 days. During follow-up at 1, 3, 6 and 12 months transthoracic echocardiography and routine clinical evaluation were performed. Patients should be treated with aspirin for up to 6 months until endothelization of the device occurs. The appropriate endocarditis prophylaxis for 6 months should be taken. The study conforms to principles outlined in the Declaration of Helsinki. The percutaneous transcatheter closure of the ASD was successful in 40 of 42 patients (95%), which was comparable with other reported series [8–11]. 2 patients had unsuccessful closure due to large defects (27 and 30 mm, respectively) and the lack of optimal rims. In one of these patients successful surgical closure of the defect was performed. Another patient has been scheduled for a second percutaneous attempt. One patient had a small hemodynamically in- significant (Qp/Os < 1.5) rest shunt due to the misdiagnosed second small defect by transthoracic echocardiography during the procedure. 39 other patients had no rest shunt during the mean follow-up period of 17 ± 29 months (range 1–42 months). No major complications (device or procedure related death, device embolization or dislodge- ment [13], subacute aortic perforation [14], atrial perforation, pericardial effusion with tamponade [15], thromboembolic events [16], major bleed- ing, groin hematoma) were observed. In 4 patients (9.5%) paroxysmal atrial fibrillation in the first month after the closure was detected and successfully treated. One patient had small pericardial effusion 1 month after the closure, which disappeared without symptoms within the next month. Atrial septal defects that result in right atrial and ventricular volume overload should be closed if diagnosed in children and adults. The possibility of future arrhythmic events is lessened and paradoxical emboli across the septum eliminated. With closure of the atrial septal defect, the left-to-right shunt is eliminated, e.g., the volume loading of the right heart, the excessive pulmonary blood flow and the total cardiac work- load are reduced. The conventional surgical approach is associated with pain, risk of wound infection, postoper- ative immobilization and a permanent scar [12]. Recently percutaneous transcatheter techniques have been available. Most of the secundum type ASDs are suitable for percutaneous closure with Amplatzer occluder less than 40 mm in diameter, and with rims greater then 5 mm from the mitral valve, orifices of venae cavae , coronary sinus and the right upper pulmonary vein. In the absence of aortic (antero-superior) rim, the ASO, if correctly sized, is sufficiently flexible to mould itself around the aortic wall with minimal risk of perforation. The presence of multiple defects does not ex- clude the possibility of a successful percutaneous catheter closure. In addition, it is possible in special clinical circumstances, e.g., during pregnancy, or, if the patients deny surgery. The assessment of suitability for percuatneous closure is done by transthoracic and transesophageal echocardiography. During the procedure, guidance with transesophageal or intracardiac echocardiography is preferable even in patients with good transthoracic echocadiographic win- dow, as additional defects can be misdiagnosed. Interventional atrial septal closure with an Amplatzer septal occluder device is a safe and effective method in patients with appropriate defect anatomy estimated by transesophagel echocardiography. No major complications occurred during the procedure and the short-term and middle- term follow-up period. Percutaneous transcatheter closure of the hemodynamically significant secundum-type atrial septal defects should be the first line treatment in experienced ...