Catheter therapy of Swiss cheese ventricular septal defects using the Amplatzer muscular VSD occluder

Transfemoral Perimembranous Ventricular Septal Defect Device Closure in Infants Weighing ≤ 10 kg

Transcatheter closure of Perimembranous VSDs (PMVSD) remains challenging particularly in infants. The aim of this study is to evaluate the efficacy and safety of transfemoral PMVSD device closure in infants weighing ≤ 10 kg in a single centre. Retrospective review of departmental databases and medical charts to define patient cohort and collect demographic, procedural and follow-up data. Between July 2014 and March 2021, 16 patients underwent attempted transfemoral PMVSD device closure (12 retrograde) at a median age of 11 months (interquartile range [IQR] 9-15.5) and a median weight of 8.3 kg (IQR 7.2-9.5). All patients were either symptomatic, had progressive left heart dilation or had VSD associated valve regurgitation. Median defect size on pre-procedural transoesophageal echocardiography was 6.8 mm (IQR 6-8.5). Median device waist size was 6 mm (IQR 4.5-8). Successful device placement was achieved in 14 patients (88%). One patient developed moderate aortic and tricuspid valve regurgitation upon retrograde and antegrade device deployment, respectively, and subsequently underwent surgical closure. The second patient developed progressive aortic regurgitation (AR) 2 days post procedure, and also underwent surgical removal with no residual AR. There was no cases of device embolization and no femoral arterial compromise. On median follow-up of 40.5 months (IQR 25-64), none of the patients developed complete heart block. Three patients (18.75%) had small residual shunts at latest follow-up which have not required any further intervention. Device closure of PMVSD's in children weighing ≤ 10 kg is feasible and safe with good procedural success rates. Use of both the antegrade and retrograde approaches may be necessary depending on anatomical variances.

A review of the therapeutic management of multiple ventricular septal defects

BACKGROUND AND AIM

We showed in our anatomical review, ventricular septal defects existing as multiple entities can be considered in terms of three major subsets. We address here the diagnostic challenges, associated anomalies, the role and techniques of surgical instead of interventional closure, and the outcomes, including reinterventions, for each subset.

METHODS

We reviewed 80 published investigations, noting radiographic findings, and the results of clinical imaging elucidating the location, number, size of septal defects, associated anomalies, and the effect of severe pulmonary hypertension.

RESULTS

Overall, perioperative mortality for treatment of residual multiple defects has been cited to be between 0% and 14.2%, with morbidity estimated between 6% and 13%. Perioperative mortality is twice as high for perimembranous compared to muscular defects, with the need for reoperation being over four times higher. Perventricular hybrid approaches are useful for the closure of high anterior or apical defects. Overall, the results have been unsatisfactory. Pooled data reveals incidences between 2.8% and 45% for device-related adverse events. Currently, however, outcomes cannot be assessed on the basis of the different anatomical subsets.

CONCLUSIONS

We have addressed the approaches, and the results, of therapeutic treatment in terms of coexisting discrete defects, the Swiss-cheese septum, and the arrangement in which a solitary apical muscular defect gives the impression of multiple defects when viewed from the right ventricular aspect. Treatment should vary according to the specific combination of defects.

Percutaneous Ventricular Septal Defect Closure in Patients Under 1 Year of Age

Untreated ventricular septal defect (VSD) is an important cause of congestive heart failure in early infancy. Growth is impaired in this population, and surgical closure is challenging because of congestion in the lungs, making infants prone to respiratory infection, and because of their poor nutritional status. The aim of this study is to share our experience with percutaneous VSD closure in patients under 1 year of age. Patients with hemodynamically significant left-to-right shunt, less than 1 year of age, and with VSD diameter ≤ 6 mm were retrospectively included in the study between December 2014 and January 2017. The median length of follow-up was 8.5 (4-14.2) months. Twelve patients from 2 to 12 months of age, with a median weight of 6.75 (5.4-8) kg, were included. The mean VSD diameter as measured by angiography from the left ventricle side was 4.7 ± 0.25 mm, and from the right ventricle side was 3.4 ± 1.1 mm. All were of a perimembranous type except three, which were muscular. All defects were closed with the Amplatzer Duct Occluder II (ADO II) or the ADO II-additional size. The mean fluoroscopy duration and total radiation dose were 22.6 ± 18.7 min and 1674 ± 851 cGy/min, respectively. No aortic regurgitation associated with device closure was seen in any of the patients. Complete atrioventricular block occurred in one patient 6 months after the procedure, and was treated with a permanent pacemaker. VSD closure is challenging, regardless of whether a surgical or percutaneous procedure is used. The risks are higher for children younger than 1 year with low body weight. Percutaneous closure, which carries similar risks but is less invasive than surgery, may be the preferred alternative in early infancy.

Recent advances in managing septal defects: ventricular septal defects and atrioventricular septal defects

This review discusses the management of ventricular septal defects (VSDs) and atrioventricular septal defects (AVSDs). There are several types of VSDs: perimembranous, supracristal, atrioventricular septal, and muscular. The indications for closure are moderate to large VSDs with enlarged left atrium and left ventricle or elevated pulmonary artery pressure (or both) and a pulmonary-to-systemic flow ratio greater than 2:1. Surgical closure is recommended for large perimembranous VSDs, supracristal VSDs, and VSDs with aortic valve prolapse. Large muscular VSDs may be closed by percutaneous techniques. A large number of devices have been used in the past for VSD occlusion, but currently Amplatzer Muscular VSD Occluder is the only device approved by the US Food and Drug Administration for clinical use. A hybrid approach may be used for large muscular VSDs in small babies. Timely intervention to prevent pulmonary vascular obstructive disease (PVOD) is germane in the management of these babies. There are several types of AVSDs: partial, transitional, intermediate, and complete. Complete AVSDs are also classified as balanced and unbalanced. All intermediate and complete balanced AVSDs require surgical correction, and early repair is needed to prevent the onset of PVOD. Surgical correction with closure of atrial septal defect and VSD, along with repair and reconstruction of atrioventricular valves, is recommended. Palliative pulmonary artery banding may be considered in babies weighing less than 5 kg and those with significant co-morbidities. The management of unbalanced AVSDs is more complex, and staged single-ventricle palliation is the common management strategy. However, recent data suggest that achieving two-ventricle repair may be a better option in patients with suitable anatomy, particularly in patients in whom outcomes of single-ventricle palliation are less than optimal. The majority of treatment modes in the management of VSDs and AVSDs are safe and effective and prevent the development of PVOD and cardiac dysfunction.

Landmark lecture on interventional cardiology: interventional cardiac catheterisation for CHD: the past, present, and the future

CHD affects millions of patients worldwide. Interventional therapies for CHD goes back to the mid-1960s when Bill Rashkind performed balloon atrial septostomy on a cyanotic baby with transposition of the great vessels. This was followed by development of balloon catheters to perform balloon valvuloplasties and angioplasties in the early to late 1980s. Although King and Mills performed the first transcatheter closure of secundum atrial septal defect in the mid-1970s, this procedure was better realised in the mid-1990s. More intracardiac defect closures were performed in the late 1990s and early 2000. This brings us to the current era of percutaneous valve implantation as developed by Bonhoeffer. In this paper, we will discuss the past, present, and future of interventional cardiac catheterisation for CHD patients.

MicroRNAs in congenital heart disease

Congenital heart disease (CHD) is a broad term which encompasses a spectrum of pathology, the most common phenotypes include atrial septal defects (ASDs), ventricular septal defects (VSDs), patent ductus arteriosus (PAD) and tetralogy of Fallot (TOF). The impact of CHD is profound and it is estimated to be responsible for over 40% of prenatal deaths. MicroRNAs (miRs) are small, highly conserved, non-coding RNAs which have complex roles in a variety of pathophysiological states. miRs are post-transcriptional negative regulators of gene expression. Individual miRs are known to exert effects in multiple target genes, therefore the altered expression of a single miR could influence an entire gene network resulting in complex pathological states. Recent evidences suggest a role in the dysregulation of miRs in CHD. Mouse knock out models have contributed to our knowledge base revealing specific patterns of miR expression in cardiovascular physiology and pathological states. Specific miRs necessary for embryonic cardiac development have been revealed. Dysregulation of these miRs has been shown to cause structural abnormalities in the heart and vasculature, thus furthering our understanding of the processes which result in CHD. These advances have provided new insight into the signalling pathways responsible for CHD. Furthermore, this new appreciation for miRs in the development of CHD has uncovered their potential for new therapeutic targets where modulated miR activity may reduce the burden of disease. Here, we summarize current knowledge of the cause-effect relationships of miRs in CHD and consider their potential as a therapeutic targets and biomarkers in this clinical setting.

Transcatheter closure of perimembranous ventricular septal defects

The isolated perimembranous ventricular septal defect is one of the most common congenital cardiac malformations. Although surgery has been performed and has a low associated risk, it still involves morbidity due to factors such as residual leaks, atrioventricular block, postpericardiotomy syndrome and arrhythmias. It has been speculated that percutaneous closure of these defects could minimize such complications. Recently, a device designed specifically for perimembranous ventricular septal defect closure, the Amplatzer membranous ventricular septal defect occluder, has been developed. Initial clinical experience with this device has been very encouraging with results showing a high rate of complete closure and a low incidence of complications at mid-term follow-up. In this article, the authors review their own and others' experience with this device.

State of the art catheter interventions in adults with congenital heart disease

Catheter interventions in adults with congenital heart disease have rapidly advanced. Transcatheter valve repair and replacement techniques have been added to the existing spectrum of well-established procedures. This review summarizes current transcatheter management strategies for congenital cardiac anomalies seen in the adult population.

Percutaneous closure of ventricular septal defects

Isolated ventricular septal defect is the most common form of congenital heart disease. Surgery has been performed for many years and is considered the gold standard for the treatment of ventricular septal defects. However, it is associated with morbidity and mortality. Less invasive techniques have been developed and currently percutaneous closure of muscular and perimembranous ventricular septal defects has to be considered a possible alternative to the standard surgical approach.

Hybrid approach for closure of muscular ventricular septal defects

BACKGROUND

The complexity of ventricular septal defects in early infancy led to development of new mini-invasive techniques based on collaboration of cardiac surgeons with interventional cardiologists, called hybrid procedures. Hybrid therapies aim to combine the advantages of surgical and interventional techniques in an effort to reduce the invasiveness. The aim of this study was to present our approach with mVSD patients and initial results in the development of a mini-invasive hybrid procedure in the Gdansk Hybrid Heartlink Programme (GHHP) at the Department of Pediatric Cardiac Surgery, Pomeranian Centre of Traumatology in Gdansk, Poland.

MATERIAL AND METHODS

The group of 11 children with mVSDs was enrolled in GHHP and 6 were finally qualified to hybrid trans-ventricular mVSD device closure. Mean age at time of hybrid procedure was 8.22 months (range: from 2.7 to 17.8 months, SD=5.1) and mean body weight was 6.3 kg (range: from 3.4 to 7.5 kg, SD=1.5).

RESULTS

The implants of choice were Amplatzer VSD Occluder and Amplatzer Duct Occluder II (AGA Med. Corp, USA). The position of the implants was checked carefully before releasing the device with both transesophageal echocardiography and epicardial echocardiography. All patients survived and their general condition improved. No complications occurred. The closure of mVSD was complete in all children.

CONCLUSIONS

Hybrid procedures of periventricular muscular VSD closure appear feasible and effective for patients with septal defects with morphology unsuitable for classic surgical or interventional procedures. The modern strategy of joint cardiac surgical and interventional techniques provides the benefits of close cooperation between cardiac surgeon and interventional cardiologist for selected patients in difficult clinical settings.

Long-term complications following surgical patch closure of multiple muscular ventricular septal defects

BACKGROUND

Multiple muscular ventricular septal defects (VSDs) in children can be difficult to treat and a range of techniques has been advocated. These include pulmonary artery banding, interventional catheter closure, and a variety of surgical approaches. When there are apical muscular defects and associated coarse trabeculations in the right ventricle (RV) producing a "Swiss cheese" pattern, a large patch extending on to the RV free wall and excluding part of the apex has been used.

METHODS

We assessed four adult patients who had surgery 22 to 45 years ago to treat muscular VSD by patches which excluded the RV apex.

RESULTS

Ages ranged from 22 to 50 years. Re-presentations were for polycythemia, cyanosis, syncope, and atrial flutter. Echocardiography showed bidirectional flow from left ventricle to apex of RV, no pulmonary hypertension, small-sized RV with diastolic dysfunction, enlarged right atria, reopening of patent foramen ovale (PFO) in three, and positive bubble studies with right to left shunting in two. Catheterization confirmed elevated right atrial and RV end diastolic pressures. Two patients had evidence of hepatic cirrhosis. One woman had device closure of PFO, but has right heart failure. One man had redo surgical closure of VSD and PFO. Another patient is being considered for a Glenn shunt to take some load off RV.

CONCLUSIONS

Surgical closure of muscular VSD by large patch with RV apical exclusion gives good early results. However, long term in adult life, the reduced size of RV, and diastolic dysfunction cause problems. These include reopening of PFO with cyanosis, right heart failure, cirrhosis, and arrhythmias.

Roles of miR-1-1 and miR-181c in ventricular septal defects

BACKGROUND

MicroRNAs (miRNAs) are endogenous noncoding RNAs of approximately 22 nucleotides in length that mediate post-transcriptional gene silencing by annealing to sequences in the 3'-untranslated region of target mRNAs.

METHODS

In this study, we analyzed 25 candidate miRNAs selected based on microarray data for cardiac tissue from individuals with congenital heart defects (CHDs) and from healthy control tissue.

RESULTS

This study identified specific changes in the miR-1-1 and miR-181c levels in human cardiac samples from individuals with ventricular septal defects (VSDs) relative to the levels in healthy control tissue. Increased levels of GJA1 and SOX9 were associated with the decreased expression of miR-1-1 in VSD patients, and increased miR-181c expression was correlated with downregulated BMPR2 levels. In addition, the results revealed that miR-1-1 and miR-181c directly regulate the expression of these predicted targets.

CONCLUSIONS

miR-1-1 and miR-181c are associated with the pathogenesis of VSDs.

Perventricular device closure of isolated muscular ventricular septal defect in infants: a single centre experience

OBJECTIVES

To evaluate prospective single centre experience of mid-term safety and efficacy of perventricular device closure of isolated large muscular ventricular septal defect (mVSD) in high-risk infants.

BACKGROUND

Surgical closures of large mVSD in infants represent a challenge with significant morbidity.

METHODS

Between August 2008-2010, perventricular closure was attempted in 24 infants of 6.01 ± 2.37 months age and 4.27 ± 0.56 kg weight under TEE guidance.

RESULTS

The device was successfully deployed in 21/24 infants. Size of mVSD was 8.42 ± 1.46 mm (6.1-12 mm). Mean procedure time was 28.8 ± 11.7 min. The closure rate was 84% immediately and 100% at 6 months. Four patients suffered major complications: 2-died, 1-esophageal perforation, 1-persistent CHB. At 26.23 ± 6.63 months follow-up two patients were symptomatic: 1-required device retrieval, 1-died of severe gastroenteritis.

CONCLUSION

Perventricular device closure of isolated mVSD appears feasible option at mid-term follow-up and may either substitute or complement the conventional surgical technique in selected cases depending on institutional paediatric cardiac surgery performance.

Left ventricular function after left ventriculotomy for surgical treatment of multiple muscular ventricular septal defects

BACKGROUND

Optimal management of muscular ventricular septal defects (MVSD) is still not determined in the current era. Moreover, long-term left ventricular function after closure of MVSD is not well known. Thus, we investigated surgical outcomes including long-term left ventricular function after closure of MVSD through left ventriculotomy.

METHODS

We conducted a retrospective review of medical records of 20 children who underwent MVSD closure between March 1993 and August 2010. There were 10 boys (50%) and 10 girls (50%). Patient age ranged from 1.6 to 103.4 months (median, 26.4 months), and body weight from 2.8 to 31.5 kg (median, 11.9 kg). Electrocardiogram results were normal sinus rhythm in all except 1 patient with congenital complete atrioventricular block. There were 16 patients who previously had palliative pulmonary artery banding procedures before closure of MVSD. There were 13 patients (65%) with Swiss-cheese type VSD.

RESULTS

There was 1 hospital death of a patient with congenital complete atrioventricular block with pacemaker malfunction (5%). There was 1 late death of a patient with del 22q with adenoviral pneumonia. There was no reoperation. Median follow-up duration was 85.9 months (range, 4.7 to 166.7). The location of MVSD was apical portion in 10 patients (50%) and midtrabecular portion in 9 patients (45%). There were 6 Dacron patch closures and 13 direct closures of MVSD through left ventriculotomy. There was no complete atrioventricular block. Last follow-up echocardiographic data showed normal ejection fraction with 65.2% ± 8.2% after closure of MVSDs. There was no leakage in 8 patients; 11 patients had insignificant leakage, which disappeared spontaneously in 4 patients 17.9 months (median value) after operation.

CONCLUSIONS

Our acceptable long-term results of left ventricular function after left ventriculotomy proved that this technique might be a viable option in the management of MVSD.

Intracoronary transplantation of genetically modified mesenchymal stem cells, a novel method to close muscular ventricular septal defects

Muscular ventricular septal defects remain a challenge despite the progress in surgical and interventional closure of ventricular septal defects. Our hypothesis was inspired by the fact that more than two thirds of children with muscular ventricular septal defects experienced spontaneous closure. Therefore, we intend to induce the spontaneous closure of muscular ventricular septal defects by means of targeted intracoronary injection of mesenchymal stem cells which are genetically modified to enhance myocardial hypertrophy. The transplantation of bone marrow derived cells has been observed to be effective in improving tissue recovery and ameliorating cardiac function in patients and animal models with ischemic heart disease, acute myocarditis and dilated cardiomyopathy. We expect that the targeted intracoronary transplantation of genetically modified mesenchymal stem cells could enhance the tissue generation and myocardial hypertrophy simultaneously, which may lead to the closure of muscular ventricular septal defects in a way that imitate the spontaneous closure of ventricular septal defects.

Novel method for delivering the Amplatzer muscular VSD occluder in a patient with double outlet right ventricle after bidirectional Glenn procedure and pulmonary artery band

We report the first use of bilateral femoral venovenous rail creation for the delivery of an Amplatzer Muscular Ventricular Septal Defect Occluder in a patient with a large mid-to-apical muscular ventricular septal defect before Rastelli operation. The presence of a right-sided bidirectional Glenn shunt, a banded main pulmonary artery, and double outlet right ventricle anatomy precluded the use of standard delivery techniques. The patient underwent successful transcatheter device placement followed by Rastelli operation on the following day.

Percutaneous Closure of Perimembranous Ventricular Septal Defect with Amplatzer Device

BACKGROUND

The Amplatzer perimembranous ventricular septal occluder is an innovative device for percutaneous closure of perimembranous ventricular septal defects (PMVSD). In appropriately selected cases this procedure is safe and effective.

METHODS

Fourteen patients with the mean age 10.53 years (range 18 months to 55 years) and mean body weight 20.64 kg (range 6 to 52 kg) underwent PMVSD closure.

RESULT

The PMVSD mean diameter was 5.28 mm (range from 4 to 9 mm). Implantation was successful in 92% of the cases and all patients had complete occlusion of the shunt within three months.

CONCLUSION

Device orientation was excellent in all cases. Device-related aortic insufficiency, tricuspid insufficiency or left ventricular dysfunction was not observed. One patient had embolisation of the device and another had complete heart block which required a permanent pacemaker implantation. The excellent short term results need to be confirmed over long-term follow-up.

Percutaneous closure of ventricular septal defects. State of the art

Ventricular septal defect (VSD) is the most common congenital heart disease. Surgery has been performed for many years and is considered to be the gold standard for the treatment of VSD. However, it is associated with morbidity and mortality. Percutaneous closure of VSDs is performed under general anesthesia and with fluoroscopic and transesophageal echocardiographic guidance. Two devices of the Amplatzer family are currently used to close percutaneously muscular and perimembranous VSD with a closure rate of 97% (incidence of major complication 2.2%) and 97.5% (major acute complications in 1.2%), respectively. Occurrence of complete atrioventricular block is reported in 1% of subjects. Acquired VSD can occur as post-surgical residual leak, as a traumatic event or as consequence of a myocardial infarction. There are few data about percutaneous closure of post-surgical residual VSD and of traumatic VSD. As for the surgical approach, in patients with post-myocardial infarction VSD success rate of percutaneous closure is around 88% with a mortality of 22%. The currently available data show that, in experienced hands, percutaneous closure is a safe and effective procedure. Device closure of muscular and perimembranous VSD is a real alternative to the standard surgical approach with the advantage of a significantly reduced rate of mortality and complications.

Septal defects: surgeons do it better

Until the recent availability of percutaneous devices, the role of the septal defect occluder was played by surgeons. In this paper the pros and cons of the two techniques in the approach to the atrial and ventricular septal defects are analyzed. Although the reported results are rather interesting, it seems clear that one of the crucial aspects to guarantee good results is the selection of patients for the transcatheter approach. Surgery is not confined by the constraints of defect anatomy, and good results may be achieved without regard to patient selection or an otherwise unfavorable anatomy of the defect. Up to now, the follow-up of transcatheter closure has been relatively short and cannot be compared with that of surgery. Therefore, caution should be exercised when proposing the transcatheter approach to septal defects as the true alternative to conventional surgery.

Cardiac conduction disturbances seen after transcatheter device closure of muscular ventricular septal defects with the Amplatzer occluder

This study examined the incidence of cardiac conduction abnormalities and ventricular arrhythmias after the transcatheter closure of muscular ventricular septal defects (MVSDs) using the Amplatzer device occluder. From the records of 27 patients who underwent 33 consecutive MVSD device closures, a low incidence of permanent and transient cardiac conduction disturbances was observed. Heart rate variability was less after the closure of multiple MVSDs compared with single MVSDs.

Percutaneous closure of postoperative ventricular septal defects with the amplatzer device

The objective of this study was to look at the procedure, the results, and the follow-up of patients who underwent percutaneous closure of a residual ventricular septal defect (VSD) following a surgical closure using the Amplatzer VSD device. Four patients had an original diagnosis of tetralogy of Fallot, two patients had a patch leak following a surgical repair of a VSD, and three patients had a VSD not repaired at the time of surgery. All patients fulfilled the currently accepted surgical criterion for reoperation (Qp/Qs>1.5). The mean Qp/Qs was 1.8+/-0.3 (1.5-2.3). Four patients underwent VSD closure using an Amplatzer perimembranous VSD device and in five patients an Amplatzer muscular VSD device was implanted. We performed percutaneous closure in nine patients. The size of the residual shunt ranged from 6 to 14 mm and the size of device used ranged from 8 to 16 mm. The arteriovenous loop needed to be recreated in two patients because of failure to advance the delivery sheath. There was complete closure of the defect in six cases, and a small residual shunt remained in three cases. Percutaneous closure of postoperative VSDs appears to be an effective way to resolve a hemodynamically significant residual shunt. There were no difficulties encountered with implantation of the devices. These promising short-term results need reinforcement with additional long-term data.

Transcatheter device versus surgical closure of ventricular septal defects: A clinical decision analysis

OBJECTIVES

To compare transcatheter device versus surgical closure of ventricular septal defects (VSDs).

METHODS

A clinical decision analysis was performed using standard gamble interviews.

RESULTS

Device was initially preferred in 39 respondents (89%) and surgery in 5 (11%). The inherent difference in value between a perfect surgery and a perfect device (disutility of surgery) was equal to a mean risk of death of (1.2 +/- 2.2)%. Final values from decision analysis were initially equivalent. Values adjusted for estimated mortality, however, favored device (mean: 0.979 +/- 0.032) versus surgery (mean: 0.971 +/- 0.032), P = 0.052. When values were further adjusted for disutilities, device was significantly preferred (0.978 +/- 0.032) versus surgery (0.961 +/- 0.044), P < 0.005. Surgery would be preferred if the probability of major complications decreased below 5% or minor complications below 6%.

CONCLUSIONS

When outcomes and their values are considered in a systematic manner, transcatheter device closure of suitable VSDs is favored over surgical repair.

Transcatheter closure of congenital ventricular septal defect with Amplatzer septal occluders

This study reports on experience with transcatheter closure of congenital ventricular septal defects (VSDs) with Amplatzer septal occluders. From January 2000 to April 2005, transcatheter Amplatzer device implantation was attempted in 122 patients with congenital VSD (30 with muscular, 87 with perimembranous, and 5 with residual postsurgical repair of conotruncal malformations). Patient mean age was 15 years (range, 6 months to 64 years), and mean weight was 35 kg (range, 5.8 to 102 kg). The VSD mean size was 7 mm (range, 4 to 16 mm), mean Qp/Qs was 2.1 (range, 1.3 to 4), and mean fluoroscopy time was 32 minutes (range, 5 to 129 minutes). All procedures were performed with the patient under general anesthesia and guided by fluoroscopy and transesophageal echocardiography. The device size chosen was usually 1- to 2-mm larger than the maximum defect size as assessed by either the echocardiographic or angiographic views that were judged most reliable. Amplatzer muscular devices were placed in 47 patients, and the membranous devices were placed in 72 patients. The procedure was not performed in 3 patients with perimembranous VSD because of the impossibility of achieving an adequate long sheath position in 1 patient, onset of complete atrioventricular (AV) block during catheter manipulation in 1 patient, and the presence of aortic valve prolapse preventing a safe device placement in 1 patient. Satisfactory device implantation was achieved in 119 of 122 patients (97.5%): a tiny smoke-like residual flow through the device was often seen immediately after the procedure (50%); residual shunting was detectable in 19% after 24 hours and in only 4% at 6 months. The following additional catheter interventions were performed simultaneously: balloon pulmonary valvuloplasty in 3 patients, device closure of atrial septal defects in 2 patients, coil occlusion of the arterial duct in 1 patient, stenting coarctation in 1 patient, and stenting of the right pulmonary artery in 1 patient. Minimal aortic regurgitation developed in 3 patients, and minimal tricuspid regurgitation in 3 patients; no patient required additional treatment. Device embolization occurred in 3 patients (1 patient with muscular VSD, 2 with perimembranous VSD); catheter retrieval and implantation of a second device was successfully performed in all patients. Transient left bundle branch block occurred in 2 patients, and transient first-degree AV block in 1 patient. Among the perimembranous VSD cases, complete AV block occurred acutely (within 48 hours) in 3 patients, requiring a pacemaker in 1 patient; complete heart block occurred in the other 2 patients after 5 and 12 months, requiring pacemakers. There was no mortality. Transcatheter closure of muscular and perimembranous VSDs offers encouraging results: 96% complete closure at midterm follow-up. Complications are limited; the most relevant appears to be device-related complete heart block in perimembranous VSD. Greater experience and long-term follow-up are required to assess the safety and effectiveness of this procedure as an alternative to conventional surgery.

Hybrid pediatric cardiac surgery

Minimally invasive strategies can be expanded by combining standard surgical and interventional techniques. We performed a longitudinal prospective study of all pediatric patients who have undergone hybrid cardiac surgery at the University of Chicago Children's Hospital. Hybrid cardiac surgery was defined as combined catheter-based and surgical interventions in either one setting or in a planned sequential fashion within 24 hours. Between June 2000 and June 2003, 25 patients were treated with hybrid approaches. Seventeen patients with muscular ventricular septal defects (mVSDs) (mean age, 4 months; range, 2 weeks-4 years) underwent either sequential Amplatzer device closure in the catheterization laboratory followed by surgical completion (group 1A, n = 9) or one-stage intraoperative off-pump device closure (group IB, n = 8) with subsequent repair of any concomitant heart lesions. Eight patients with branch pulmonary artery (PA) stenoses (group 2) underwent intraoperative PA stenting or stent balloon dilatation along with concomitant surgical procedures. All patients survived hospitalization. Complications from the hybrid approach were mostly confined to groups 1A and 2. At a mean follow-up of 18 months, 2 group 1A patients died suddenly several months after discharge. All other patients are doing well. Hybrid pediatric cardiac surgery performed in tandem by surgeons and cardiologists is safe and effective in reducing or eliminating cardiopulmonary bypass. Patients with mVSDs who are small, have poor vascular access, or have concomitant cardiac lesions are currently treated in one setting with the perventricular approach.

Outcome of transcatheter closure of muscular ventricular septal defects with the Amplatzer ventricular septal defect occluder

OBJECTIVES

To present further experience and intermediate term outcome in 30 patients with single muscular ventricular septal defects (MVSDs) who underwent transcatheter closure with the Amplatzer ventricular septal defect occluder (AVSDO).

PATIENTS AND DESIGN

Thirty patients, aged 4 months to 16 years, with MVSDs underwent transcatheter closure with the AVSDO. The device consists of two low profile disks made of Nitinol wire mesh with a 7 mm connecting waist. The prosthesis size (waist diameter) was selected to be equal to the balloon "stretched" diameter of the defect. A 7-9 French sheath was used to deliver the AVSDO. Fluoroscopy and transoesophageal echocardiography guided the procedure.

RESULTS

The stretched diameter of the defects ranged from 6-14 mm. The communication was completely occluded in 28 of 30 patients (93% closure rate). One patient (a 4 month old infant) with sustained complete left bundle branch block after the procedure went on to develop complete heart block one year later. No other complications were observed during a mean follow up of 2.2 years (range 0.25-4.5 years).

CONCLUSIONS

The AVSDO is an efficient prosthesis that can be safely used in the majority of patients with a single MVSD. Further studies are required to establish long term results in a larger patient population.

Multicenter experience with perventricular device closure of muscular ventricular septal defects

Hybrid procedures are becoming increasingly important, especially in the management of congenital heart lesions for which there are no ideal surgical or interventional options. This report describes a multicenter experience with perventricular muscular venticular septal defect (VSD) device closure. Three groups of patients (n = 12) were identified: infants with isolated muscular VSDs (n = 2), neonates with aortic coarctation and muscular VSDs (n = 3) or patients with muscular VSDs and other complex cardiac lesions (n = 2), and patients with muscular VSDs and pulmonary artery bands (n = 5). Via a sternotomy or a subxyphoid approach, the right ventricle (RV) free wall was punctured under transesophageal echocardiography guidance. A guidewire was introduced across the largest defect. A short delivery sheath was positioned in the left ventricle cavity. An Amplatzer muscular VSD occluding device was deployed across the VSD. Cardiopulmonary bypass was needed only for repair of concomitant lesions, such as double-outlet right ventricle, aortic coarctation, or pulmonary artery band removal. No complications were encountered using this technique. Discharge echocardiograms showed either mild or no significant shunting across the ventricular septum. At a median follow-up of 12 months, all patients were asymptomatic and 2 patients had mild residual ventricular level shunts. Perventricular closure of muscular VSDs is safe and effective for a variety of patients with muscular VSDs.

Hybrid procedures in pediatric cardiac surgery

Hybrid pediatric cardiac surgery is an emerging field that combines skills and techniques used by pediatric cardiac surgeons and interventional pediatric cardiologists. This article describes the emerging indications and techniques in hybrid pediatric cardiac surgery and discusses potential future applications. It focuses on peratrial and perventricular septal defect closure, intraoperative stenting, hybrid stage I palliation for hypoplastic left heart syndrome, and percutaneous valve implantation.

Device closure of muscular ventricular septal defects using the Amplatzer muscular ventricular septal defect occluder

OBJECTIVES

We sought to report the results of a U.S. registry of device closure of congenital muscular ventricular septal defects (VSDs) using the new Amplatzer mVSD occluder (AGA Medical Corp., Golden Valley, Minnesota).

BACKGROUND

Muscular VSDs pose a significant surgical challenge with increased morbidity and mortality.

METHODS

Data were prospectively collected from 83 procedures involving 75 patients who underwent an attempt of percutaneous (70 [93.3%] of 75) and/or perventricular (surgical) (6 [8.0%] of 75) device closure of hemodynamically significant muscular VSDs. The patients' median age was 1.4 years (range 0.1 to 54.1 years). Outcome parameters were procedural success, evidence of residual shunts on echocardiography, and occurrence of procedure-related complications. The median follow-up was 211 days (range 1 to 859 days).

RESULTS

The median size of the primary VSD was 7 mm (range 3 to 16 mm) and in 34 of 78 (43.6%) procedures, patients had multiple VSDs (range 2 to 7). The device was implanted successfully in 72 of 83 (86.7%) procedures. In 17 of 83 (20.5%) procedures, multiple devices were implanted (range 2 to 3). Procedure-related major complications occurred in 8 of 75 (10.7%) patients. Device embolization occurred in two patients and cardiac perforation in one patient. There were two (2.7%) procedure-related deaths. The 24-h postprocedural complete closure rate was 47.2% (34 of 72 patients), increasing to 69.6% (32 of 46 patients) at 6 months and 92.3% (24 of 26 patients) at 12 months. Six patients underwent successful closure using the perventricular surgical (beating heart) approach, with complete closure at day 1 in three patients and trivial/small residual shunts in the remainder of the patients.

CONCLUSIONS

The Amplatzer mVSD device (AGA Medical Corp.) offers excellent closure rates and low mortality when used to close congenital muscular VSDs. The device appears to be safe and effective.

Perventricular device closure of muscular ventricular septal defects on the beating heart: technique and results

OBJECTIVE

Both surgical management and percutaneous device closure of muscular ventricular septal defects have drawbacks and limitations. This report describes our initial experience with intraoperative device closure of muscular ventricular septal defects without cardiopulmonary bypass in 6 consecutive patients.

METHODS

A median sternotomy or a subxiphoid minimally invasive incision was performed. Under continuous transesophageal echocardiographic guidance, the right ventricle free wall was punctured, and a wire was introduced across the largest defect. The Amplatzer (AGA Medical Corporation, Golden Valley, Minn) muscular ventricular septal defect occluding device (a self-expandable double-disk device) was used. An introducer sheath was fed over the wire, with the sheath tip positioned in the left ventricle cavity. The device was then advanced inside the sheath and deployed by retracting the sheath. Associated cardiac lesions, if any, can then be repaired during cardiopulmonary bypass. A similar technique can also be applied for periatrial closure of complex atrial septal defects.

RESULTS

The initial 6 patients are presented. Cardiopulmonary bypass was not needed in any patient for placement of the device and needed in 4 patients for repair of concomitant malformations only (double-outlet right ventricle, aortic arch hypoplasia, pulmonary artery band removal). No complications from using this technique occurred. Discharge echocardiograms showed no significant shunting across the ventricular septum.

CONCLUSIONS

Perventricular closure of multiple muscular ventricular septal defects is safe and effective. We believe that this could become the treatment of choice for any infant with muscular ventricular septal defects or any child with muscular ventricular septal defect and associated cardiac defects.

Catheter Closure of Atrial Septal and Ventricular Septal defects Using The Amplatzer Devices

The Amplatzer Septal Occluder (ASO) is a device that combines the advantages of being a double-disc with a self-centering mechanism. It is the first and only device to ever receive full approval for clinical use in children and adults with secundum atrial septal defects (AD) from the United States Food and Drug Administration. It has been used successfully to close secundum ASDs, patent foramen avale and Fontan fenestrations. The first patient to undergo closure with the ASO was approximately 6 years ago. So far the mid-term results are very encouraging with no long-term complications for the presence of the device. Complications encountered with the use of the Amplatzer septal occluder are rare and most may be managed in the catheter laboratory. Most of the complications occur in the immediate period post-implantation. The Amplatzer muscular and membranous ventricular septal defect devices are still undergoing clinical trials in the United States; however, they are fully approved in many countries. Long-term results about safety and efficacy, as well as results involving larger defects are being collected.

Catheter closure of perimembranous ventricular septal defects using the new Amplatzer membranous VSD occluder: initial clinical experience

The surgical closure of membranous ventricular septal defects (VSDs) is associated with morbidity and low mortality. Six patients with VSDs located in the membranous part of the ventricular septum underwent an attempt of catheter closure using a new device specifically designed for the membranous septum. Patients ranged in age from 3.5 to 19 years (median, 10.5 years) and in weight from 15 to 45 kg (median, 29 kg). One patient with associated pulmonary valve stenosis had shortness of breath. The median Qp/Qs ratio was 1.6 (range, 1.1-3) and the median left ventricle end-diastolic dimension (LVEDD) was 44 mm (range, 38-52 mm). The devices were deployed via the femoral vein using 7-8 Fr sheaths. There was immediate complete closure in all patients. One patient developed trivial aortic regurgitation. There were no other complications. The median fluoroscopy time was 15.5 min (range, 10.3-53.4 min). At 24 hr, all patients were doing well. The median LVEDD decreased to 38 mm (range, 34-47 mm). One patient continued to have trace aortic regurgitation. All patients were discharged home after 24 hr. Transcatheter occlusion of membranous VSDs is safe and effective. Further clinical trials are underway to assess the long-term safety and results.