Echocardiographic estimation of balloon-stretched diameter of secundum atrial septal defect for transcatheter occlusion.

Stretched diameter of the atrial septal defect (ASD), determined by balloon sizing at cardiac catheterization, is commonly used to select the sizes of the devices used for transcatheter closure of the secundum ASD. We have previously evaluated the utility of pulmonary/systemic flow ratio and angiographic and echocardiographic (echo) sizes of the ASD in estimating stretched ASD diameter in a group of 16 patients and determined that echo diameter had the best correlation with stretched diameter (r = 0.82; p less than 0.001). The stretched diameter can be estimated: 1.05 x echo diameter in millimeters + 5.49. In this study we have prospectively evaluated this formula in estimating the stretched ASD diameter by two-dimensional echo measurements obtained in two (long and short-axis) subcostal views in another group of 21 patients aged 2.5 to 29 years (median 4.5 years). The echo size of the ASD was 9.7 +/- 3.0 mm, whereas the measured stretched diameter was 15.3 +/- 4.0 mm. The predicted stretched ASD diameter was calculated according to the above formula and was 15.7 +/- 3.1 mm, not significantly different (p greater than 0.1) from the measured stretched diameter. The correlation between predicted and measured stretched ASD sizes was excellent (r = 0.9; p less than 0.001). The mean squared error was 2.4. The differences between measured and predicted values were within 2 mm in all but three patients. It is concluded that stretched ASD diameter can be estimated accurately by two-dimensional subcostal echo measurements, which in turn could be used for selection of device size for occlusion of the ASD.     

Role of "buttoned" double-disc device in the management of atrial septal defects.

Sixteen patients seen over a 9-month period ending in August 1990 were offered transcatheter closure of their ASD with a custom-made "buttoned" double-disc device. The study was approved by the Institutional Review Board and informed consent was obtained in each case. The device consists of an occluder, a counteroccluder, and a loading wire and is delivered to the ASD site via an 8F sheath. Parents of two children elected surgical closure. In five children the stretched diameter of the ASD was too large (greater than 20 mm) and transcatheter closure was not attempted. These seven children underwent elective surgical closure without incident. In one child the defect measured 5 mm and the Qp:Qs was 1.4:1 and therefore ASD closure was not recommended. In the remaining eight children transcatheter closure was attempted. In two of the children the occluder pulled through the ASD and was successfully retrieved and the children later underwent uneventful elective surgical closure. The device was implanted across the ASD in six children. In one child the device dislodged from the ASD site within minutes after implantation and the child was sent to emergency surgery, where the device was removed and the ASD was closed. In the remaining five patients, aged 7 months to 45 years (weight 3.6 to 50 kg), with a Qp:Qs range of 1.3 to 2.3 and a stretched diameter of 10 to 19 mm, the ASD closure was successful with 25 to 40 mm size devices. Repeat echo-Doppler studies 2 weeks and 3 months after the procedure in all patients and 6 months later in two children did not reveal any residual shunt. It is concluded that (1) the custom-made "buttoned" double-disc device can be implanted across the ASD safely and effectively via an 8F sheath, thus making transcatheter ASD closure feasible even in very young infants; (2) measurement of stretched diameter of the ASD in the catheterization laboratory is a useful guide for selection of an appropriate-sized device; and (3) additional clinical trials are warranted to confirm the efficacy and safety of the device.     

Determinants of cardiopulmonary functional improvement after transcatheter atrial septal defect closure in asymptomatic adults

OBJECTIVES: We sought to evaluate the course of cardiopulmonary function after transcatheter atrial septal defect (ASD) closure and to identify the physiopathologic mechanisms leading to this change. BACKGROUND: Conflicting reports exist on cardiopulmonary functional improvement in asymptomatic adults after transcatheter closure of a secundum ASD. METHODS: Thirty-two consecutive adults (13 males; age 42.6 +/- 16.7 years) underwent maximal cardiopulmonary exercise testing and transthoracic echocardiography both on the day before and six months after transcatheter ASD closure. Mean pulmonary artery pressure, pulmonary to systemic flow ratio (Qp/Qs), and ASD diameter were measured before closure. RESULTS: Peak oxygen uptake (Vo(2)) (p < 0.001), peak oxygen pulse (p = 0.0027), and vital capacity (p = 0.0086) improved after ASD closure, although peak heart rate did not. A significant correlation was found between peak Vo(2) improvements and Qp/Qs (p = 0.0013). Left ventricular ejection fraction (LVEF) (p < 0.0001) and left ventricular end-diastolic diameter (LVEDD) (p < 0.0001) significantly increased after six months, although left ventricular end-systolic diameter did not. Right ventricular long- and short-axis dimensions decreased (both p < 0.0001). Peak Vo(2) and of peak oxygen pulse improvements correlated to both LVEF (p = 0.0009 and 0.0019, respectively) and LVEDD (p < 0.0001 and 0.032, respectively) increments. The decrease of both long- and short-axis right ventricular dimensions positively correlated to both LVEF and LVEDD improvements. The improvement in LVEF correlated to Qp/Qs (p = 0.0026). CONCLUSIONS: Transcatheter ASD closure leads to a significant improvement in cardiopulmonary function within six months, via an increase in peak oxygen pulse. An increase in both left ventricular stroke volume and cardiac output due to a positive ventricular interaction is the mechanism leading to improved peak Vo(2).     

Diagnostic catheterization and balloon sizing of atrial septal defects by echocardiographic guidance without fluoroscopy

To avoid x-ray exposure prior to interventional closure of atrial septal defects (ASDs), we recently developed a technique for diagnostic catheterization and balloon sizing of the defect by echocardiographic guidance without fluoroscopy. We report on our first experiences with this technique. Fourteen patients with atrial septal perforations (mean age, 23 years; range, 1-66 years) underwent diagnostic catheterization and balloon sizing prior to possible interventional defect closure. Mean size of the defects was 16 mm (7-29 mm). Mean left-to-right shunt was Qp/Qs = 2.0 (range, 1.0-4.0). Without fluoroscopy, the procedures were performed in two children by transthoracic echocardiography (TTE) and in 12 patients by both TTE and transesophageal echocardiography (TEE). Mean procedure time was 59 minutes (range, 35-90 minutes). We conclude that oxymetry, pressure recordings, and the estimation of the balloon-stretched size of atrial septal perforations can be performed safely by echocardiographic guidance without fluoroscopy. The x-ray exposure for patient selection prior to a transcatheter closure of an ASD can be avoided with this technique.     

Transcatheter closure of interatrial communications with Amplatzer device: results, unfulfilled attempts and special considerations in children and adolescents.

OBJECTIVE: We report our clinical experience with the Amplatzer device in transcatheter closure of 80 atrial septal defects (ASD) in children. METHODS: Among 99 patients (mean age: 7.2+/-3.8 years) with ASD selected by transthoracic echocardiography, procedures were performed in 80 patients under general anesthesia with fluoroscopic and transesophageal echocardiographic (TEE) guidance. Optimal device size was selected after stretched balloon sizing of the ASD's. The patients were discharged at 24 hours after an evaluation with X-ray, electrocardiography and echocardiography. RESULTS: The mean follow-up period (FUP) was 38+/-14 months. Mean ASD size was 11.5+/-3.7 mm at TEE (stretched size: 17.6+/-3.9 mm). The mean size of the device was 18.6+/-4.0 mm. Procedure and fluoroscopy time were 52.1+/-17.8 minutes and 11.0+/-4.9 minutes, respectively. Immediately after the procedure 35 patients (43.8%) had residual shunts. Trivial shunt remained in only 2 of them (2.5%) after FUP. None of the patients had major complications. Minor and transient rhythm abnormalities were observed in 5 patients and trivial mitral regurgitation was seen in 6 patients. CONCLUSION: Amplatzer is an effective and safe device for transcatheter closure of ASD especially in pediatric patients.     

Assessment of atrial septal defect size with 3D-transesophageal echocardiography: comparison with balloon method

BACKGROUND: Transcatheter closure of atrial septal defect (ASD) is an alternative approach to surgery in selected patients. Balloon stretched diameter (BSD) is considered as the standard way of measuring ASD size. Three-dimensional transesophageal echocardiography (3D-TEE) provides views of the ASD allowing its measurement and identifying its spatial relation with neighboring structures. Our aim was to compare the BSD and 3D-TEE methods to measure the ASD size before transcatheter closure. METHODS AND RESULTS: Seventy-six consecutive patients were enrolled for ASD device closure. Three-dimensional transesophageal echocardiography and balloon sizing were adequately performed in 70 patients before the defect closure. The mean maximal diameter measured by 3D-TEE was 20 +/- 15 mm (range 10-28) while the mean BSD was 22 +/- 4.8 mm (range 9-31). When comparing the 3D-TEE and transcatheter measurements, there was a good correlation between the two methods (y = 3.15 + 0.77x; r = 0.8). The defect as viewed by 3D-TEE was unique in 54 patients and multiple in 16 patients. In patients with a single defect, the correlation between the two methods was high (y = 1.74 + 0.84x; r = 0.85) while patients with multiple ASDs, the correlation was poor (y = 12.4 + 0.4x; r = 0.45). Transcatheter closure was performed successfully in 86%. The mean size of the Amplatzer device was 23 +/- 4.8 mm (range 4-32). The reference to choose the size of the device was the BSD in single defects and the 3D-TEE maximal diameter in multiple defects. CONCLUSION: Three-dimensional transesophageal echocardiography and transcatheter methods are two complementary techniques for the success of transcatheter ASDs closure.     

Transcatheter closure of atrial septal defects with the Amplatzer septal occluder--a Japanese clinical trial.

This study reports the results of a Japanese clinical trial of transcatheter closure of atrial septal defects (ASD) using the Amplatzer septal occluder (ASO). Thirty-five patients with secundum ASD underwent transcatheter closure using the ASO at a median age of 12.9 years (range, 3.2-29.2 years) and a median weight of 39.2kg (range, 11.6-65.1 kg). The ASO was successfully implanted in 34 patients. The mean ASD diameter of the 34 patients measured by transesophageal echocardiography was 11.7 +/- 4.2mm (range, 5.0-20.8mm) and the mean balloon stretched diameter was 16.8 +/- 4.2 mm (range, 9-25 mm). The mean ASO size was 16.9 +/- 4.3 mm (range, 9-26mm). Complete closure rate at 1 day and 1 year after closure was 91% and 97%, respectively. One patient developed a transient second-degree atrioventricular block during the implantation procedure. No other complications occurred. Transcatheter closure of ASD using the ASO is effective and safe.     

经胸超声心动图在Amplatzer封堵器治疗成人巨大房间隔缺损中的应用

目的　评价经胸超声心动图监测 (TTE)Amplatzer封堵器介入治疗巨大房间隔缺损(ASD)的安全性和可行性。方法　 2 1例住院患者 ,男 12例 ,女 9例 ;年龄 17～ 4 5岁 ;均经临床及超声心动图证实的继发孔型ASD ,以充盈球囊最大伸展直径加 2～ 4mm为原则选择封堵器型号 ,TTE监测下放置Amplatzer封堵器。随访有无残余分流及是否影响周围瓣膜和静脉功能 ,记录临床事件 (血栓栓塞、心功能不全、心律失常等 )。结果　 2 1例全部封堵成功 ,TTE监测放置Amplatzer封堵成功 ,手术成功率 10 0 % ;术后即刻及 1天、3天、3个月、6个月、1年复查TTE观察无明显残余分流及影响周围瓣膜功能 ,也无腔、肺静脉狭窄 ,无血栓栓塞事件发生 ,无封堵器移位和脱落 ,心功能有不同程度的好转。1例发生频发房性心律失常 ,经心律平 4 5 0mg d治疗 1个月后消失 ,无其他并发症发生。结论　Amp latzer封堵器介入治疗成人巨大ASD是一种安全、有效的治疗方法 ,TTE监测ASD介入封堵治疗整个过程 ,可以提高一次释放成功率     

Transcatheter atrial septal defect closure: modified balloon sizing technique to avoid overstretching the defect and oversizing the Amplatzer septal occluder.

The objective of this study was to evaluate a new technique of sizing atrial septal defects (ASDs) for transcatheter device closure. ASD closure using the Amplatzer septal occluder (ASO) device is commonly performed. Complications, including arrhythmias, pericardial effusions, and perforations, may be related to oversizing ASDs and choosing larger devices. Two methods were used to size ASDs using a compliant balloon. In some patients, the balloon was inflated until a waist was visible [(+)waist]; in others, only until no shunting was demonstrable by echocardiogram [echo; (-)waist]. The device was selected and implanted using standard procedure and echo guidance. One hundred seventeen patients underwent secundum ASD closure with an ASO device. There were 43 patients in the (-)waist group and 74 in the (+)waist group. All devices were implanted successfully. The initial echo ASD diameter was larger in the (-)waist group compared to the (+)waist group (P = 0.01). There was a smaller difference between the initial echo and balloon-sized ASD diameters in the (-)waist group (P < 0.02). ASO device size implanted (in mm greater than echo ASD diameter) was smaller in the (-)waist group (P < 0.01). There were 0/43 complications in the (-)waist group and 5/74 in the (+)waist group. The complete closure rate was the same in both groups. Sizing an ASD by inflating a compliant balloon just until shunting is eliminated, and not until a waist is visible, results in less overstretching of the ASD and selection of a smaller ASO device, achieving similar closure rates and potentially fewer complications.     

Sizing of atrial septal defects in adults

In a retrospective study of 51 consecutive patients undergoing transcatheter closure of secundum type atrial septal defects (ASDs), we examined the reliability of transesophageal echocardiography (TEE) prior to catheterization and compared the diameter with that obtained by balloon measurement during catheterization. The TEE diameter was 16.3+/-4.6 mm compared with 22.5+/-6.0 mm for the stretched diameter obtained during catheterization (p<0.001). There was no gender difference. The degree of left-to-right shunting correlated poorly with the size of the defect. We conclude that although TEE is accurate for diagnosis of an ASD, the measurement of its size to determine the size of the closure device is at best inaccurate.     

Interventional occlusion of atrial septum defects larter than 20 mm in diameter

Over the last few years, various devices for the interventional closure of atrial septal defects (ASD) up to a diameter of 20 mm have been developed. We report our clinical experience in closing ASD with a diameter larger than 20 mm 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 2-4 mm 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 7 mm 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 20 mm diameter (median 22 mm diameter (20-36), 25/75% quartiles = 20/26 mm). Mean shunt size was Qp:Qs 2.1:1 (0.7-3.9:1), mean fluoroscopy time 10.9 min (0-63). Complete closure could be achieved in 85.7/93.1/100% after 3 months, 1 and 2 years, respectively. Besides 3 P with persistent atrial fibrillation, only 5 P showed transient atrial tachyarrhythmias, 2 only periprocedural and 3 within the first 3 months after implantation were treated with beta-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.     

Usefulness of live three-dimensional transthoracic echocardiography in the characterization of atrial septal defects in adults

In this report we present 12 adult patients in whom surgical or percutaneous intervention was considered for repair of atrial septal defect (ASD). Location, size, and surrounding atrial anatomy of the ASD were assessed prior to intervention in all patients with standard and live three-dimensional transthoracic echocardiography (3D TTE). In the four patients in whom intraoperative three-dimensional transesophageal echocardiographic reconstruction (3D TEE) was done, 3D TTE measurements of maximum dimension, maximum circumference, and maximum area of ASD agreed well with 3D TEE. In the seven patients who underwent transcatheter closure device insertion, live 3D TTE measurements of maximum dimension, maximum circumference, and maximum area of ASD agreed well with the sizing balloon. Additionally, since the sizing balloon measures a stretched diameter and area, a live 3D TTE stretched ASD diameter and area (derived from the actual live 3D TTE maximum circumference) were calculated and demonstrated improved agreement with the sizing balloon measurements. In all patients, > or =5 mm of atrial tissue was visualized surrounding the ASD. Further, with the addition of contrast enhancement, characterization of a small patent foramen ovale (<5 mm) was possible in one patient. Live 3D TTE accurately defined ASD location, size, and surrounding atrial anatomy in all patients studied by us. ASD characterization by live 3D TTE agreed well with 3D TEE and sizing balloon measurements.     

Choice of device size and results of transcatheter closure of atrial septal defect using the amplatzer septal occluder

The impact of device size choice on closure results was analyzed in 138 (101 females, 37 males; age 0.5-84.0 years) consecutive patients who underwent transcatheter closure of the secundum atrial septal defect (ASD) using the Amplatzer septal occluder (ASO). The balloon stretched diameter (SD) of ASD was 19.5 +/- 7.2 mm in 123 patients with single defects, and 20.4 +/- 6.6 mm for the largest defects in 15 patients with multiple ASDs. The difference (delta) between ASO size chosen for closure and the stretched diameter of the defect was calculated and divided into groups: A (delta < -2 mm); B (delta -2.0 to -0.1 mm); C (delta = 0); D (delta 0.1-2.0 mm) and E (delta > 2 mm). The results demonstrated that immediate and 24-hour complete closure rates were significantly higher in patients in groups C and D (P < 0.001). However, at 6-month follow-up, the complete closure rates were similar in patients of groups A-D, while patients of group E had a lower closure rate of 75%. The complication rates were similar in all groups. In conclusion, a choice of a device size identical to or within 2 mm larger than the SD of the defect should be used to maximize the closure rates of ASD using the ASO.     

Transcatheter closure of atrial septal defect without balloon sizing

Objective: To evaluate the safety and feasibility of transcatheter closure of atrial septal defect (ASD) without balloon sizing. Methods: A total of 243 patients (group I), aged 2.1–76 years (median 22 years), underwent transcatheter closure of ASD without balloon sizing. The maximal diameter of the defect was measured on transesophageal echocardiographic (TEE) images. The size of device selected was generally 4–6 mm and 5–8 mm larger than the maximal diameter, if the defect was <14 mm and ≥14 mm, respectively. The results of ASD closure in group I were compared with those of 271 patients (group II, median age 11 years) who underwent ASD closure with balloon sizing prior to the study period. Results: Of the 243 patients in group I, the maximal defect diameter ranged from 5.2 to 37 mm (mean 17.5 ± 6.6 mm, median 17 mm). A total of 247 Amplatzer septal occluders were deployed in 240 patients. Two patients were found to develop distal embolization of a device the next day. Therefore, failure occurred in five patients. Comparing the results between group I and group II, there was no significant difference in success rate (238/243 vs. 263/271), incidence of embolization (2/243 vs. 2/271) and complete closure rate at 3‐month follow‐up (94.1% vs. 95.8%). There is significant difference in mean age (26.6 ± 20.2 vs. 19.1 ± 17.6), maximal defect diameter (17.5 ± 6.6 vs. 14.1 ± 5.9 mm) and Q_p/Q_s ratio (2.77 ± 1.11 vs. 2.48 ± 0.97) between group I and II. The mean diameter of device used was significantly larger in group I than in group II (23.1 ± 8.1 vs. 19.6 ± 7 mm, P < 0.001). Conclusions: Balloon sizing may not be necessary in transcatheter closure of ASD. © 2008 Wiley‐Liss, Inc.     

房间隔缺损经导管封堵术对心率变异性的影响及意义

目的探讨房间隔缺损(ASD)经导管封堵术对心率变异性(HRV)的影响及意义。方法选择成功接受介入治疗的ASD患者118例为研究对象(ASD组),分别于术前1天及术后第4天记录24h动态心电图,由电脑自动分析并经心电专业人员校正,得出HRV的各项时域指标;另按术前心脏超声测得的肺循环血流量/体循环血流量(Qp/Qs)分为Ⅰ组(Qp/Qs<1.5)与Ⅱ组(Qp/Qs≥1.5),分析两亚组患者HRV,并行Qp/Qs与HRV的相关性分析。结果与对照组比较,ASD组封堵术前后24hRR间期标准差(SDNN)及24h内每5min节段RR间期均值标准差(SDANN)均显著降低(P<0.01或0.05);Ⅱ组降低更明显。ASD组封堵术后RR间期、SDNN及SDANN均较术前增加(P<0.05);Ⅱ组介入治疗术后的SDNN、ASDNN较Ⅰ组术后明显减小(P<0.05)。ASD患者术前SDNN及SDANN与Qp/Qs呈负相关(r值分别为-0.528、-0.644,P<0.01)。结论ASD封堵术后HRV水平明显恢复;Qp/Qs越大的ASD患者不仅术前HRV水平降低更显著,术后的恢复也越慢。     

New echocardiographic diameter for Amplatzer sizing in adult patients with secundum atrial septal defect: preliminary results.

Anatomical atrial septal defect (ASD) diameter measured by transesophageal echocardiography (TEE) underestimates the Amplatzer septal occluder (ASO) size for ASD closure. The aim of this study is to investigate whether a new echocardiographic diameter (procedural ASD diameter) may enable precise measurements of ASO device size. Fifty adult patients with secundum ASD were evaluated by TEE for percutaneous closure. The procedural ASD diameter was measured using the steadier rim borders where thickness was 2.5 mm. Out of the 50 patients, 12 were considered unsuitable for Amplatzer device closure. The other 38 patients underwent percutaneous closure. The mean anatomical ASD diameter was 14.8 +/- 7.0 mm, the mean procedural ASD diameter measured 19.5 +/- 8.1 mm, and the mean stretched balloon diameter (SBD) was 20.0 +/- 8.0 mm. ASO device size was 20.1 +/- 8.0 mm. At linear regression analysis, a high correlation (r = 0.99) was found between procedural ASD diameter and SBD. Procedural ASD diameter correlates with SBD and may allow reliable prediction of Amplatzer device in an adult population undergoing percutaneous ASD closure.     

Pulmonary blood flow alters nitric oxide production in patients undergoing device closure of atrial septal defects

OBJECTIVE: To determine the effect of pulmonary blood flow (Qp) on nitric oxide (NO) production in patients with increased Qp due to an atrial septal defect (ASD). BACKGROUND: Alterations in pulmonary vascular NO production have been implicated in the development of pulmonary hypertension secondary to increased Qp. In vitro, acute changes in flow or shear stress alter NO production. However, the effect of Qp on lung NO production in vivo is unclear. METHODS: Nineteen patients (2.4-61 years of age, median 17) with secundum ASD undergoing device closure were studied. Before, and 30 min after ASD closure, exhaled NO and plasma nitrate concentration were measured by chemiluminescence (NOA 280, Sievers, Boulder, Colorado). RESULTS: Before ASD closure, all patients had increased Qp (Qp: systemic blood flow [Qs] of 2.0 +/- 0.7) and normal mean pulmonary arterial pressure (13.4 +/- 3.1 mm Hg). Atrial septal defect device closure decreased Qp from 6.0 +/- 2.5 to 3.6 +/- 1.3 L/min/m2 (p < 0.05). Mean pulmonary arterial pressure was unchanged. Associated with the decrease in Qp, both exhaled NO (-22.1%, p < 0.05) and plasma nitrate concentrations (-17.9%, p < 0.05) decreased. CONCLUSIONS: These data represent the first demonstration that acute changes in Qp alter pulmonary NO production in vivo in humans. Exhaled NO determinations may provide a noninvasive assessment of pulmonary vascular NO production in patients with congenital heart disease. Potential correlations between exhaled NO, pulmonary vascular reactivity and pulmonary hypertension warrant further study.     

Role of intracardiac echocardiographic guidance in transcatheter closure of atrial septal defects and patent foramen ovale using the Amplatzer device

Transesophageal echocardiography (TEE) has been successfully used for guiding transcatheter device closure of secundum atrial septal defect (ASD) and patent foramen ovale (PFO). However, the use of TEE for device closure requires general anesthesia. Experience with intracardiac echocardiographic (ICE) guidance to close ASD and PFO is limited. One hundred eleven patients (76 female/35 male) with secundum ASD (82 patients) and PFO (29 patients) associated with a stroke underwent an attempt of transcatheter closure of their defects under ICE guidance using the new AcuNav catheter. The median age of patients was 40 years (range 2.5-80.7) and the median weight was 66 kg (range 12.7-128 kg). The median two-dimensional size of secundum defects as measured by ICE was 17 mm (range 3-32 mm). The median balloon stretched diameter of the ASDs was 22 mm (range 4-36 mm). Five patients had more than one defect that required placement of two devices to close the defects. The median Qp/QS ratio for patients with secundum ASD was 2.1 (range 1-18). ICE provided adequate views of the defects and surrounding structures and the various stages of device deployment. All patients had successful device placement, including the patients who received simultaneous two devices with immediate complete closure of the defects in 100 patients, whereas four and seven patients had trivial and small residual shunt, respectively. The median fluoroscopy time was 10.2 minutes (range 3.7-38.4 minutes) and the median total procedure time was 60 minutes (range 28-180 minutes). There were no complications related to the use of the AcuNav catheter. We conclude that ICE provided unique images of the atrial communications and facilitated device closure of secundum ASD and PFO in children and adults. We believe ICE should replace TEE as a guiding imaging tool for ASD and PFO device closure, thus eliminating the need for general anesthesia.     

Noninvasive evaluation of the ratio of pulmonary to systemic flow in atrial septal defect by duplex Doppler echocardiography

The ratio of pulmonary to systemic flow (Qp/Qs) was noninvasively evaluated by duplex Doppler echocardiography in 22 patients with atrial septal defects (ASDs). Right and left ventricular stroke volumes (RSV, LSV) were determined from the recordings of ejection blood flow velocity and diameter at the level of the pulmonary and aortic orifices in each ventricular outflow tract. The ratio RSV/LSV, determined by the duplex Doppler echocardiography, was compared with Qp/Qs by oximetry. The RSV/LSV for 10 normal subjects was 0.99 +/- 0.05 (mean +/- SD), whereas the RSV/LSV for patients with ASD, 2.26 +/- 0.63, was significantly higher than that for normal subjects (p less than .01). In patients with ASD, a fairly good correlation was found between RSV/LSV and Qp/Qs (r = .92, p less than .01; y = 1.11x - 0.30), and this high correlation was found even in patients with complications such as pulmonary hypertension, mitral and tricuspid regurgitation, Eisenmenger complex, and ventricular septal defect. We also found that semilunar valve regurgitation modified the value of RSV/LSV in accordance with the degree of regurgitation. These findings indicate that, with a few limitations, the Doppler index RSV/LSV is clinically useful in the estimation of the magnitude of the shunt flow in patients with ASD and that the limitations could be overcome by additional Doppler examination.     

Transcatheter closure of atrial septal defects in children & adults using the Amplatzer Septal Occluder

We are reporting the worldwide experience in closing atrial septal defects (ASDs) in children and adults using the Amplatzer Septal Occluder (ASO) as of July 2000. The outcome measures were safety and efficacy with special emphasis on: (1) immediate success of the ASD closure as measured by transesophageal echocardiography (TEE), (2) short- and medium-term follow-up at 24 hours and 1 and 3 months and long-term follow-up at 1, 2, and 3 years as assessed by transthoracic echocardiography (TTE); and (3) the incidence of complications. In all, 3580 procedures were performed in 3535 patients. In 75 patients, the device was not implanted for variety of reasons; 3460 patients received a single ASO device and 45 received two devices for multiple ASDs. The median age of the patients was 12.1 year, (range, 10 days-88 years, the median weight was 41.0 kg (range, 2.4-137 kg) and the median Qp/Qs ratio was 2 (range, 0.3-10). The median size of ASD by TEE was 14 mm (range, 1-38 mm) and the median stretched diameter was 18 mm (range, 4-44 mm). The median size of device implanted was 18 mm (range, 4-40 mm). The median fluoroscopy time was 17.1 minutes (range, 0.0-194.0 minutes). The immediate success rate including those patients with complete closure, trivial residual shunt, or with small residual shunt was 97.4%. This increased to 99.2% and 100% at 3 months and 3 years, respectively. Minor complications were encountered in 2.8% of procedures, while serious complications occurred in less than 0.3% of the cases. There were no device related deaths. We conclude that the ASO is a safe and effective device for catheter closure of small to large ASDs up to a stretched diameter of 40 mm in children and adults with very high short-, medium, and long-term success rates.