Percutaneous balloon valvotomy in pulmonary atresia with intact ventricular septum: impact on patient care

Novel Uses of the SwiftNinja Steerable Microcatheter for Pediatric Cardiovascular Interventions

In the present era, the intricacy of procedures undertaken by a pediatric interventional cardiologist has increased, primarily attributed to dealing with smaller, younger patients with more complex anatomies. To adapt to these smaller and more complex patients, we must adapt our interventions and our equipment to perform these procedures. This article outlines various innovative applications of the SwiftNinja steerable microcatheter within the pediatric cardiac catheterization laboratory.

Current status of transcatheter intervention for complex right ventricular outflow tract abnormalities

Various transcatheter interventions for the right ventricular outflow tract (RVOT) have been introduced and developed in recent decades. Transcatheter pulmonary valve perforation was first introduced in the 1990s. Radiofrequency wire perforation has been the approach of choice for membranous pulmonary atresia in newborns, with high success rates, although complication rates remain relatively common. Stenting of the RVOT is a novel palliative treatment that may improve hemodynamics in neonatal patients with reduced pulmonary blood flow and RVOT obstruction. Whether this option is superior to other surgical palliative strategies or early primary repair of tetralogy of Fallot remains unclear. Transcatheter pulmonary valve replacement has been one of the biggest innovations in the last two decades. With the success of the Melody and SAPIEN valves, this technique has evolved into the gold standard therapy for RVOT abnormalities with excellent procedural safety and efficacy. Challenges remain in managing the wide heterogeneity of postoperative lesions seen in RVOT, and various technical modifications, such as pre-stenting, valve ring modification, or development of self-expanding systems, have been made. Recent large studies have revealed outcomes comparable to those of surgery, with less morbidity. Further experience and multicenter studies and registries to compare the outcomes of various strategies are necessary, with the ultimate goal of a single-step, minimally invasive approach offering the best longer-term anatomical and physiological results.

Application of Foley balloon catheter in palliative surgery for pulmonary atresia with an intact ventricular septem, with additional cases of pulmonary atresia with ventricular septal defect and tetralogy of Fallot

BACKGROUND

Pulmonary atresia and tetralogy of Fallot can require palliative surgery in the neonatal period due to severe hypoxia; however, limitations of established techniques include high failure rate and need for cardiopulmonary bypass. Herein, right ventricular outflow tract reconstruction on a beating heart using a Foley balloon catheter is described.

METHODS

A retrospective review of patients who underwent right ventricular outflow tract reconstruction on a beating heart using a Foley balloon catheter at our institution between September 2018 and March 2022 was completed. During the procedure, a Foley balloon catheter was used to occlude the blood from the right ventricular inflow tract.

RESULTS

Eight patients with pulmonary atresia and intact ventricular septum underwent an off-pump right ventricular outflow tract reconstruction. One patient with pulmonary atresia and ventricular septal defect, and two patients with tetralogy of Fallot underwent an on-pump right ventricular outflow tract reconstruction on a beating heart. The procedures were successful in all patients. Patent ductus arteriosus ligation without modified Blalock-Taussig shunt placement was performed in three patients with pulmonary atresia with intact ventricular septum and two patients with tetralogy of Fallot, ductus arteriosus was left open in four patients with pulmonary atresia with intact ventricular septum. All patients remained clinically well without serious complications.

CONCLUSIONS

Right ventricular outflow tract reconstruction on a beating heart using a Foley balloon catheter for pulmonary atresia and tetralogy of Fallot is a feasible alternative to catheter-based interventions or traditional surgical treatment, especially in patients with muscular infundibular stenosis or hypoplastic pulmonary annulus. Further studies with more cases are needed to verify feasibility and superiority of this approach.

A retrograde approach for transcatheter valvotomy procedure in infants with pulmonary atresia intact ventricular septum (PA-IVS): retrograde versus antegrade approach

INTRODUCTION

This study evaluates the retrograde approach compared to the antegrade approach in infants with PA-IVS who underwent transcatheter pulmonary valvotomy procedure at National Cardiovascular Center Harapan Kita, Jakarta, Indonesia.

MATERIAL AND METHOD

This is a single-centre retrospective study conducted from January 2017 to June 2019 consisting of infants undergoing transcatheter pulmonary valvotomy procedures from our centre.

RESULTS

Among 3733 records of cardiac catheter procedure in paediatric patients during the last 3 years, there were 12 subjects with PA-IVS, where five subjects were done by antegrade approach and seven by retrograde approach. The retrograde approach is shown to excel the antegrade approach in terms of procedural time by 58.64 minutes (CI 95 % 32.97-84.29, p = 0.008) and PA-RV crossing time by 27 minutes (CI 95 % 14.01-39.99, p = 0.02). There was no significant difference in contrast used (120.23 ± 25.77 versus 150.27 ± 39.26 ml/BSA, p = 0.518), and right ventricle to pulmonary artery systolic pressure gradient after valvotomy (39.571 ± 5.814 versus 53.52 ± 29.15, p = 0.329) between the retrograde and the antegrade approach.

CONCLUSION

The retrograde approach offered shorter procedural time and comparably satisfying results than the antegrade approach. The shorter procedural time was preferred due to the shorter duration of general anaesthesia, which may decrease the risk of neurodevelopmental deficits in the patient.

An Up-to-Date Narrative Review on Congenital Heart Disease Percutaneous Treatment in Children Using Contemporary Devices

Background: Congenital heart pathology has a significant burden regarding morbidity and mortality in the pediatric population. Several transcatheter interventions and devices have been designed as an alternative to surgical repair. Percutaneous interventions have been proven to yield good results in most cases but with less stress and trauma than that attributed to surgical treatment, especially in frail pediatric patients. We aimed to review the literature and to investigate the feasibility and efficacy of transcatheter interventions and implantable devices for congenital heart disease management in children. Methods: We performed a search in Scopus and MEDLINE databases using prespecified keywords to retrieve clinical studies published between 2000 and 2021. Results: This article provides an up-to-date review regarding the applicability of interventional techniques in simple inter-atrial or inter-ventricular defects, and in challenging congenital defects, such as hypoplastic left heart syndrome, tetralogy of Fallot, or coronary artery fistula. Furthermore, we reviewed recent indications for defibrillator and cardiac resynchronization therapy, and new and promising devices currently being tested. Conclusion: Transcatheter treatment represents a feasible and efficient alternative to surgical repair of congenital heart defects. Novel devices could extend the indications and possibilities of percutaneous interventions in pediatric patients with congenital heart diseases.

Long-Term Outcomes After an Individualized Strategy in Patients with Pulmonary Atresia and Intact Ventricular Septum

This retrospective cohort study aimed to explore the long-term outcomes of an individualized strategy in patients with pulmonary atresia and intact ventricular septum (PAIVS). We analyzed survival and reintervention rates and identified risk factors for outcomes in patients with PAIVS treated based on individual right heart structures between 1979 and 2019. Ninety-five patients were included in this study. The z-scores of the pulmonary annulus, tricuspid annulus, and right ventricular end-diastolic volume were - 3.30 (- 15.15 to 1.83), - 0.70 (- 4.65 to 2.33), and - 1.51 (- 6.35 to 1.18), respectively. Right ventricular-dependent coronary circulation occurred in 15% of the patients. Among the 63 patients attempting biventricular strategy at first, 55 patients achieved biventricular circulation, 3 patients had one-and-a-half circulation, and 4 patients died perioperatively. Among the 33 patients attempting univentricular strategy at first, 10 patients died before the completion of Fontan operation, 17 patients (48%) accomplished Fontan operation, and 5 patients waited for Fontan operation. In one patient, conversion to biventricular circulation occurred. During the follow-up period of 720 person-years, the 20-year survival rate was significantly higher in patients with biventricular circulation than in those patients with univentricular circulation (93% vs. 67%, P < 0.001). Freedom from reintervention rates at 20 years was significantly lower in patients with biventricular circulation than in those patients with univentricular circulation (29% vs. 72%, P < 0.001). The pulmonary annulus z-score was an independent risk factor for reintervention in patients with biventricular circulation. Patients with biventricular circulation had an acceptable survival rate, but a high reintervention rate. Meanwhile, patients with univentricular circulation had high mortality before the completion of Fontan operation, although the reintervention rate was relatively low.

Application of Vessel Navigator™ fusion imaging software in a complex transcatheter palliation of Tetralogy of Fallot with pulmonary atresia

Extreme pulmonary artery hypoplasia in cyanotic malformations precludes palliative surgeries. When aortopulmonary collaterals (APC) in such patients are also hypoplastic, their unifocalization to create a neopulmonary vasculature is also hampered. Stent angioplasty of the outflow or collateral arteries may reduce hypoxia but is challenging in tortuous and atretic tracts. Fusion imaging overlays anatomical data from computed tomography during adult structural interventions, but its use is not often reported in young children with complex cyanotic malformations. This report shows utility of fusion imaging in pulmonary atresia with extremely hypoplastic pulmonary arteries and stenotic APC to guide stenting of outflow tract and collaterals.

Increasing Use of Neonatal Catheter Intervention for Pulmonary Atresia With Intact Ventricular Septum: Management Trends From a Single Centre

BACKGROUND

There is increasing use of catheter-based therapy as part of the neonatal treatment algorithm for pulmonary atresia with an intact ventricular septum (PAIVS). The management strategies utilised and outcomes of patients with PAIVS at our centre have not been examined.

METHODS

A retrospective case series was undertaken including all infants with PAIVS born January 2009 to July 2019 (follow-up to January 2020) managed at The Children's Hospital at Westmead, New South Wales. Demographic features, anatomical substrate, management pathway and subsequent clinical outcomes were examined.

RESULTS

Fifty-two (52) infants were included (male n=28, 53.8%). The right ventricular morphology was classified as normal, mildly, moderately and severely hypoplastic in 3 (5.8%), 13 (25.0%), 19 (36.5%) and 17 (32.7%) patients respectively. Thirty-seven (37) patients underwent an initial aortopulmonary (AP) shunt (surgical shunt or patent ductus arteriosus [PDA] stent). The remaining 15 patients underwent an initial intervention to decompress the right ventricle. Twenty (20) patients underwent a neonatal catheter-based intervention. An initial catheter-based intervention was more likely in the second half of the period. Sixteen (16) patients had an attempted pulmonary valve perforation, 12 as their initial procedure. Median follow-up was 62 months (range 3-119 months). Final circulation status was known in 37 patients; biventricular n=14 (37.8%), "1.5 ventricles" n=4 (10.8%), single n=19 (51.4%). There were five deaths during the period (9.6%), including two during the initial procedural admission attributed to tamponade requiring extracorporeal membrane oxygenation (ECMO) at the time of percutaneous pulmonary valve perforation.

CONCLUSION

There has been an overall trend towards including catheter-based strategies in the neonatal period as part of management at our centre. Given the risk of bleeding and ECMO related to this, consideration should be given to the availability of multidisciplinary support when planning the timing of these procedures.

Percutaneous Balloon Pulmonary Valvuloplasty of Critical Pulmonary Stenosis and severe pulmonary stenosis in Neonates and Early Infancy: A Challenge in the Cyanotic

Introduction: Pulmonary stenosis with an intact ventricular septum (PS-IVS) is one of the common causes of cyanotic heart disease in neonates with diverse morphologies as well as management and treatment protocols. The aim of this study was to evaluate short and midterm results of balloon pulmonary valvuloplasty (BPV) for this disorder.

Methods: Between 2012 and 2016, Totally 45 neonates and infants under 6 months old were evaluated.The patients had a minimum right-to-left ventricular pressure ratio of 1, right-to-left shunting at the patent foramen ovale or atrial septal defect level, and tricuspid valve Z-scores higher than -4.

Results: Immediately after the procedure, the right ventricular pressure dropped to the normal values in 8 (20%) patients. The immediate procedural success rate was seen in 42 (93.3%) cases: the right-to-left ventricular pressure ratio dropped to below 50% or the level of O2 saturation rose above 75%. Of three cases unresponsive to BPV, two of them underwent patent ductus arteriosus (PDA) stenting and one procedural death occurred. At 6 months’ follow-up, of 42 patients, this pressure was still with in the normal range in 36 (80%) infants, while it had returned to high values in 9 (20%) patients and necessitated repeat valvuloplasty. After BPV, severe pulmonary valve regurgitation was observed in14.2% patients; the condition was more common when high-profile noncompliant balloons were used.

Conclusion: Balloon pulmonary valvuloplasty in infants with PS-IVS confers acceptable results insofar as it improves echocardiographic parameters and hemodynamic changes at short- and midterm followups.Balloon selection with sizes more than 1.2 of the diameter of the pulmonary valve annulus and the use of noncompliant high-pressure balloons results in higher degrees of pulmonary regurgitation.

Late adverse events in patients with pulmonary atresia intact ventricular septum after valvuloplasty

BACKGROUND

We aimed to explore the relationship between temporal right heart growth and long-term outcomes in patients with pulmonary atresia with intact ventricular septum (PA/IVS) who underwent balloon pulmonary valvulopalsty (BPV).

METHODS

Echocardiography was performed to measure the pulmonary valve diameter (PVD), the right atrial end-systolic area (RAA), and the right ventricular end-diastolic area (RVA) before BPV, 1 and 5 years after BPV. The primary and secondary endpoints were to explore temporal changes in the right heart structures and to determine echocardiographic parameters related to late adverse events (LAEs).

RESULTS

In 31 patients, PVD significantly increased after BPV, whereas TVD remained unchanged throughout the follow-up period of 9.1 (5.7-12.0) years. After BPV, RAA temporally decreased, whereas RVA significantly increased. There were six LAEs (19%); arrhythmias in two, heart failure in one, reintervention of the right ventricular outflow tract in one, and reintervention for residual cyanosis in two. The rate of freedom from LAEs at 5 and 10 years were 92% and 82%, respectively. RAA temporally decreased in patients without LAEs (P<0.01); however, RAA remained unchanged throughout the period in patients with LAEs (P=0.16). Moderate or severe pulmonary regurgitation (PR) (hazard ratio [HR], 23.0; 95% confidence interval [CI], 1.3-385; P=0.03) and the ratio of RVA /RAA at 1 year after BPV (HR, 6.3×10^-11; 95%CI, 2.1×10^-20-0.19; P=0.03) were independent risk factors for LAEs.

CONCLUSIONS

Disproportional right heart growth was observed in patients with PA/IVS after BPV. PR and increased RAA are crucial in identifying the burden of LAEs among them.

Is there a transcatheter solution for a sick neonate with hypoplastic right heart syndrome?: Pulmonary valve perforation in a neonate with hypoplastic right ventricle with pulmonary atresia, restrictive VSD-a case report

BACKGROUND

Hypoplastic right heart syndrome with pulmonary atresia is a rare cyanotic heart disease with poor prognosis requiring urgent intervention to establish the pulmonary blood flow. Pulmonary blood flow is achieved by BT shunt or percutaneous techniques like PDA stenting or pulmonary valve perforation. Various series have shown that early surgical intervention causes high mortality in these patients. Pulmonary valve perforation is a suitable, physiological alternative to surgical techniques in selected patients.

CASE PRESENTATION

We report a case of hypoplastic right heart syndrome with pulmonary atresia and restrictive VSD presenting with cyanosis from birth and underwent pulmonary valve perforation successfully.

CONCLUSION

Duct-dependent pulmonary circulation is a pediatric emergency, palliative procedure for establishing adequate pulmonary blood flow is essential early in the life. In the management of duct-dependent pulmonary circulation, RVOT perforation is an effective and safe option in suitable high-risk subgroups. The induced pulmonary regurgitation along with established physiological antegrade flow would be beneficial in the remodeling of tripartite/hypertrophied small RV.

Transcatheter radiofrequency pulmonary valve perforation in newborns with pulmonary atresia/intact ventricular septum: Echocardiographic predictors of biventricular circulation

OBJECTIVE

We report a single-institute experience of neonatal transvenous radiofrequency pulmonary valve perforation for pulmonary atresia/intact ventricular septum, with echocardiographic predictors of biventricular circulation.

METHODS

Data were reviewed retrospectively for all neonates who underwent primary transvenous pulmonary valve perforation for pulmonary atresia/intact ventricular septum between January 2008 and November 2018 at our institution. We compared patients who need systemic-to-pulmonary shunt or ductal stenting with patients who did not need.

RESULTS

During the study period, 31 patients with pulmonary atresia/intact ventricular septum underwent successful radiofrequency pulmonary valve perforation and balloon dilation of the pulmonary valve. There was no procedure-related mortality. Sixteen patients (52%) needed systemic-to-pulmonary shunt or ductal stenting after initial procedure. Among the survivors (follow-up time of 1 to 11.5 years), 15 patients had a biventricular circulation and 6 patients had 1 and 1⁄2 ventricular circulation. Two patients are awaiting for Fontan operation. Both the TV/MV annulus ratio (>0.85) and tricuspid valve z-score (>-1) were found to be a good predictor of a biventricular outcome in our cohort.

CONCLUSIONS

Percutaneous radiofrequency pulmonary valve perforation and balloon valvotomy is an effective and safe primary treatment strategy for neonates with pulmonary atresia/intact ventricular septum. Ductal stenting or systemic-to-pulmonary shunt may be required in the majority of patients who had smaller right heart components. Preselection of patients according to tricuspid valve z-score and TV/MV annulus ratio allows predicting biventricular circulation.

An Overview of Contemporary Outcomes in Fetal Cardiac Intervention: A Case for High-Volume Superspecialization?

Fetal cardiac interventions (FCI) offer the opportunity to rescue a fetus at risk of intrauterine death, or more ambitiously to alter disease progression. Most of these fetuses require multiple additional postnatal procedures, and it is difficult to disentangle the effect of the fetal procedure from that of the postnatal management sequence. The true clinical impact of FCI may only be discernible in large-volume institutions that can commit to a standardized postnatal approach and have sufficient case volume to overcome their FCI learning curve.

Transcatheter pulmonary valvuloplasty in neonates with pulmonary atresia and intact ventricular septum

BACKGROUND

Transcatheter pulmonary valvuloplasty in neonates with pulmonary atresia and intact ventricular septum (PA-IVS) or duct-dependent pulmonary valve stenosis (DD-PVS) has become a reasonable alternative to surgical right ventricle decompression.

AIM

To investigate mid-term outcomes following pulmonary valvuloplasty.

METHODS

Sixty-five neonates with PA-IVS (n=29) or DD-PVS (n=36) (median age 4 days; mean weight 3.0kg) undergoing pulmonary valvuloplasty were reviewed retrospectively. Procedural data and clinical outcomes were assessed.

RESULTS

Pulmonary valvuloplasty was successful in 59 patients (90.8%). Preterm birth, larger tricuspid valve annulus diameter and PA-IVS correlated with procedural failure. Eleven patients (18.6%) required a Blalock-Taussig shunt during early follow-up, despite valvuloplasty. These neonates had smaller tricuspid and pulmonary valve annulus Z-scores (-1.9 vs. -0.8 [p=0.04] and -2.5 vs. -0.9 [P=0.005], respectively) and a higher incidence of "bipartite" right ventricle (P=0.02). Mean follow-up was 5.4±3.3 years. Mortality after successful valvuloplasty was 8.5% (n=5). Among the 54 survivors, biventricular repair was achieved in 52 patients (96.3%), including nine with a previous Blalock-Taussig shunt. The cumulative rate of subsequent surgery (excluding Blalock-Taussig shunt) was 13.7% (95% confidence interval 6.8-26.7%) and 16.4% (95% confidence interval 8.5-30.4%) at 2 and 4 years, respectively. Secondary surgery was significantly more frequent in PA-IVS compared with DD-PVS, and in neonates with a Blalock-Taussig shunt (P=0.003 and 0.01, respectively).

CONCLUSIONS

Selected neonates with DD-PVS or PA-IVS managed by transcatheter pulmonary valvuloplasty had a good mid-term outcome. In neonates with a borderline small right ventricle, a hybrid strategy with a supplementary source of pulmonary blood flow can be efficient to achieve biventricular repair.

Technical factors are associated with complications and repeat intervention in neonates undergoing transcatheter right ventricular decompression for pulmonary atresia and intact ventricular septum: results from the congenital catheterisation research collaborative

BACKGROUND

Transcatheter right ventricle decompression in neonates with pulmonary atresia and intact ventricular septum is technically challenging, with risk of cardiac perforation and death. Further, despite successful right ventricle decompression, re-intervention on the pulmonary valve is common. The association between technical factors during right ventricle decompression and the risks of complications and re-intervention are not well described.

METHODS

This is a multicentre retrospective study among the participating centres of the Congenital Catheterization Research Collaborative. Between 2005 and 2015, all neonates with pulmonary atresia and intact ventricular septum and attempted transcatheter right ventricle decompression were included. Technical factors evaluated included the use and characteristics of radiofrequency energy, maximal balloon-to-pulmonary valve annulus ratio, infundibular diameter, and right ventricle systolic pressure pre- and post-valvuloplasty (BPV). The primary end point was cardiac perforation or death; the secondary end point was re-intervention.

RESULTS

A total of 99 neonates underwent transcatheter right ventricle decompression at a median of 3 days (IQR 2-5) of age, including 63 patients by radiofrequency and 32 by wire perforation of the pulmonary valve. There were 32 complications including 10 (10.5%) cardiac perforations, of which two resulted in death. Cardiac perforation was associated with the use of radiofrequency (p=0.047), longer radiofrequency duration (3.5 versus 2.0 seconds, p=0.02), and higher maximal radiofrequency energy (7.5 versus 5.0 J, p<0.01) but not with patient weight (p=0.09), pulmonary valve diameter (p=0.23), or infundibular diameter (p=0.57). Re-intervention was performed in 36 patients and was associated with higher post-intervention right ventricle pressure (median 60 versus 50 mmHg, p=0.041) and residual valve gradient (median 15 versus 10 mmHg, p=0.046), but not with balloon-to-pulmonary valve annulus ratio, atmospheric pressure used during BPV, or the presence of a residual balloon waist during BPV. Re-intervention was not associated with any right ventricle anatomic characteristics, including pulmonary valve diameter.

CONCLUSION

Technical factors surrounding transcatheter right ventricle decompression in pulmonary atresia and intact ventricular septum influence the risk of procedural complications but not the risk of future re-intervention. Cardiac perforation is associated with the use of radiofrequency energy, as well as radiofrequency application characteristics. Re-intervention after right ventricle decompression for pulmonary atresia and intact ventricular septum is common and relates to haemodynamic measures surrounding initial BPV.

Transcatheter perforation of atretic pulmonary valve by the stiff end of a coronary wire in neonates with pulmonary atresia with intact ventricular septum: A solution in developing countries

Objectives

To evaluate the safety of using the stiff end of a coronary wire to perforate an atretic pulmonary valve (PV) in patients with pulmonary atresia with intact ventricular septum (PAIVS).

Background

Radiofrequency perforation is an accepted modality to perforate the PV in patients PAIVS. However, the high cost precludes its widespread use.

Patients and methods

This is a single-center experience that spanned from March 2013 to January 2016 and involved 13 neonates who were severely cyanotic with PAIVS and with ductal-dependent pulmonary circulation. The stiff end of a coronary wire was used to perforate the atretic PV anterogradely, followed by balloon pulmonary valvuloplasty.

Results

The mean age of patients was 3.9 ± 2.7 days and their mean weight was 2.8 ± 0.19 kg. The mean oxygen saturation was 77.1 ± 3.2%. All had membranous pulmonary atresia, with patent infundibulum and tripartite right ventricle. The valve was successfully perforated in 11 out of 13 patients. Death occurred in two patients (15.4%) owing to heart failure and sepsis. Patent ductus arteriosus stenting was performed 2 days after the procedure in one patient because of cyanosis followed by one and half ventricle repair at of age 5 months. Two patients (15.4%) had one and a half ventricle repair at age of 5 months and 6 months owing to insufficient anterograde pulmonary flow. Two patients (15.4%) underwent second intervention with balloon dilatation of the valve. The remaining seven patients (53.8%) had no further intervention. Two cases (15.4%) had femoral artery thrombosis treated with streptokinase. The mean duration of follow-up was 13.17 ± 7 months. There was significant improvement in the degree of tricuspid incompetence. There was a significant growth in the tricuspid valve annulus during the follow-up (the mean Z score increased from −0.8 ± 0.9 to 0.1 ± 0.9) (p = 0.003). There was also a significant increase in the tricuspid valve annulus/mitral valve annulus ratio as its mean increased from 0.73 ± 0.10 to 0.86 ± 0.11 during follow-up (p < 0.001).

Conclusion

Perforation of the atretic PV in selected cases with membranous atresia and patent infundibulum using the stiff end of a coronary wire is an effective alternative to using radiofrequency perforation.

Perforation and right ventricular outflow tract stenting: Alternative palliation for infants with pulmonary atresia/ventricular septal defect

BACKGROUND

Right ventricular outflow tract (RVOT) stents have been used as palliation in patients with severe tetralogy of Fallot (TOF). Radiofrequency perforation of the RVOT has also been described in patients with pulmonary atresia (PA)/ventricular septal defect (VSD). However, RVOT stenting in conjunction with radiofrequency perforation as a means for establishing reliable pulmonary blood flow in patients with PA/VSD has not previously been reported.

OBJECTIVES

Our aim is to report our experience with using perforation of plate-like pulmonary valve atresia combined with stenting of RVOT as an alternative and equally efficacious intervention for infants with PA/VSD, as compared to a surgical pulmonary artery shunt (SPS).

METHODS

A retrospective review of patients with PA/VSD at our institution from Jan 2006 to October 2015 was performed.

RESULTS

Twenty-seven patients received palliation for PA/VSD. Five (median 2.5 kg, 2.1-4.1 kg) underwent RVOT stenting and 22 (3.5 kg, 2.1-4.6 kg) underwent surgical SPS. Of the patients who received an RVOT stent, 3 underwent guidewire perforation and balloon dilation of the plate-like pulmonary valve, and 2 underwent radiofrequency perforation of the pulmonary plate, followed by balloon dilation. Postprocedure saturations averaged 93% in the stent group and 89% in the shunt group. One of the patients who underwent RVOT stenting required additional stenting of the PDA for isolation of the LPA, but none required re-intervention. Four patients in the SPS cohort required re-intervention (18%). Two required stenting of the shunt, and 2 required surgical revision of the shunt. There was one death in the stent group, however this was secondary to withdrawal of support given an underlying genetic diagnosis (trisomy 13). There was one fatality in the SPS cohort prior to hospital discharge.

CONCLUSIONS

Perforation followed by RVOT stenting may be a safe and effective alternative to surgical SPS in infants with PA/VSD.

Transthoracic Balloon Pulmonary Valvuloplasty for Treatment of Congenial Pulmonary Atresia Patients with Intact Ventricular Septum

Background

To summarize our clinical experience in performing transthoracic balloon pulmonary valvuloplasty for the treatment of patients suffering from congenial pulmonary atresia with intact ventricular septum (PA/IVS).

Material/Methods

Between April 2009 and April 2016, 38 patients with PA/IVS underwent transthoracic balloon pulmonary valvuloplasty in our hospital. All of them were combined with patent ductus arteriosus, tricuspid insufficiency, and atrial septal defect or patent foramen ovale. The valvuloplasty was performed from the right ventricular outflow tract through a median sternotomy incision under TEE guidance for all cases.

Result

Thirty-five patients were successfully discharged, and 3 patients died after the operation. The 35 surviving patients were followed up. Spo2 in the 35 patients was 88–96% after the operation. The transpulmonary valvular gradient pressure was less than or equal to 30 mmHg in 31 patients and between 36 and 52 mmHg in the other 4 patients. After the surgery, tricuspid regurgitation was significantly reduced. We found only 4 patients with moderate regurgitation, 5 patients with mild to moderate regurgitation, and mild regurgitation in the remaining 26 patients. Five patients underwent a second-stage operation, including biventricular repair in 4 patients and ligation of ductus arteriosus in 1 patient.

Conclusions

The application of transthoracic balloon pulmonary valvuloplasty for the treatment of PA/IVS is minimally invasive and safe, which has great significance for improving the curative effect for this condition and reducing operation mortality.

Radiofrequency perforation of the pulmonary valve: an efficient low cost solution

Objective The aim of the study was to assess the feasibility of using commonly available catheterization laboratory equipment for radiofrequency perforation of the pulmonary valve in patients with pulmonary atresia and intact ventricular septum. Methods The system (off-label use for all items) is made up of a co-axial telescopic arrangement consisting of a 0.014" PT 2 ™ coronary guidewire, for insulation inside a 2.7-F microcatheter which has an inner lumen of 0.021". The microcatheter was passed via a standard 4-F right coronary catheter to just below the atretic pulmonary valve. Radiofrequency (RF) energy was delivered using a standard electrosurgical system. In vitro testing had been performed and indicated that 5-10 W for 2-5 s would be sufficient for valve perforation. Results Radiofrequency perforation was successfully performed in all (n = 5, 100%) patients at a median age of 3 days (range: 1-36) and weight 2.7 kg (range 2.3-3.0). In one patient the pericardium was entered during the initial attempt; the generator was put on coagulation mode during retrieval of the guidewire and no haemopericardium occurred. The pulmonary valve was dilated in all; in three patients (n = 3) the ductus arteriosus was stented during the same session. Conclusion Results of the study show that it is feasible to perforate the pulmonary valve safely using this system. Availability, simplicity and cost are noteworthy benefits.

Outcomes After Decompression of the Right Ventricle in Infants With Pulmonary Atresia With Intact Ventricular Septum Are Associated With Degree of Tricuspid Regurgitation

Background—

Outcomes after right ventricle (RV) decompression in infants with pulmonary atresia with intact ventricular septum vary widely. Descriptions of outcomes are limited to small single-center studies.

Methods and Results—

Neonates undergoing RV decompression for pulmonary atresia with intact ventricular septum were included from 4 pediatric centers. Primary end point was reintervention post-RV decompression; secondary end points included circulation type at latest follow-up. Ninety-nine patients (71 with pulmonary atresia with intact ventricular septum and 28 with virtual atresia) underwent RV decompression at median 3 (25th–75th, 2–5) days of age. Seventy-one patients (72%) underwent at least 1 reintervention after decompression. Median duration of follow-up was 3 years (range, 1–10). Freedom from reintervention was 51% at 1 month and 23% at 3 years. In multivariable analysis, reintervention was associated with virtual atresia (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.28–091; P =0.027), smaller RV length (HR, 0.94; 95% CI, 0.89–0.99; P =0.027), and ≤mild tricuspid regurgitation (TR; HR, 3.58; 95% CI, 2.04–6.30; P <0.001). Patients undergoing surgical shunt or ductal stent were less likely to have virtual atresia (HR, 0.36; 95% CI, 0.15–0.85; P =0.02) and more likely to have higher RV end-diastolic pressure (HR, 1.07; 95% CI, 1.00–1.15; P =0.057) and ≤mild TR (HR, 3.50; 95% CI, 1.75–7.0; P <0.001). Number of reinterventions was associated with ≤mild TR (rate ratio, 1.87; 95% CI, 1.23–2.87; P =0.0037). Multivariable analysis indicated that <2-ventricle circulation status was associated with ≤mild TR (odds ratio, 18.6; 95% CI, 5.3–65.2; P <0.001) and lower RV area (odds ratio, 0.81; 95% CI, 0.72–0.91; P <0.001).

Conclusions—

Patients with pulmonary atresia with intact ventricular septum deemed suitable for RV decompression have a high reintervention burden although most achieve 2-ventricle circulation. TR ≤mild at baseline is strongly associated with reintervention and <2-ventricle circulation at medium-term follow-up. Degree of baseline TR may be an important marker of long-term outcomes in this population.

Outcomes of Radiofrequency Perforation for Pulmonary Atresia and Intact Ventricular Septum: A Single-Centre Experience

Percutaneous radiofrequency perforation (RFP) of the pulmonary valve is used as a primary therapy in neonates with pulmonary atresia and intact ventricular septum (PAIVS). We sought to determine the safety and efficacy of RFP for PAIVS in a single center and assess the pre-intervention anatomical parameters associated with a biventricular outcome. We retrospectively reviewed all cases of PAIVS treated with RFP at a single center from 1999 through 2012. We collected baseline imaging data, technical aspects of the procedure, adverse events and outcomes. RFP was attempted in 18 patients with 17 successful procedures. There was no mortality; one patient had an acute complication requiring surgical intervention. All were alive at the most recent follow-up (median 4.9 years; IQR = 2.0-6.8 years), 12/17 (71%) had a biventricular circulation, 2/17 (12%) had a 1½ ventricle repair, 2/17 (12%) had a univentricular repair and 1/17 was lost to follow-up. A biventricular outcome in patients with PAIVS was associated with the pre-intervention tricuspid valve/mitral valve (TV/MV) ratio and tricuspid valve (TV) z-score. The median TV/MV ratio for patients who underwent a biventricular repair and a non-biventricular repair was 0.82 (IQR = 0.71-0.90) and 0.59 (IQR = 0.39-0.76), P = 0.036, respectively. The median TV z-scores were -3.2 [(-4.9 to -2.6), and -6.8 (-9.7 to -4.8] P = 0.036 for the biventricular and non-biventricular groups, respectively. RFP is a safe primary therapy for PAIVS. With appropriate patient selection, RFP will often result in a biventricular circulation. Both the TV/MV and TV z-score were found to be a predictor of a biventricular outcome in our cohort.

Intervention in Patients with Critical Pulmonary Stenosis in the Ductal Stenting Era

We aimed to assess early and midterm outcomes of balloon valvuloplasty (BVP) procedure in patients with critical pulmonary stenosis (CPS) and to describe the predictors of the need for additional pulmonary flow and reintervention in this subgroup of patients. From 2005 to 2014, 56 neonates were diagnosed with CPS and were included in this study. All echocardiographic, catheterization and angiographic data obtained prior to the initial BVP and at follow-up were reviewed. BVP was successful in 55 neonates (98 %). Twenty-one neonates needed pulmonary blood flow augmentation after BVP (38 %). Ductal stenting (DS) was performed in 20. The patients' mean tricuspid valve (TV) annulus diameter was 10.4 ± 2 mm, and the Z score was -1.29 ± 1 (-3.7 to 0.78). The mean pulmonary valve (PV) annulus diameter was 6 ± 0.9 mm, and the Z score was -1.74 ± 1 (-4.34 to 0.05). A transcatheter or surgical reintervention was performed in 11 patients. A TV Z score < -1.93 SD predicted the need for pulmonary blood flow augmentation after a successful BVP, with a sensitivity of 63.2% and a specificity of 84.4%. A PV Z score < -1.69 SD predicted the need for pulmonary flow augmentation, with a sensitivity of 74 %. The presence of bipartite RV was found to be a significant predictor of the need for reintervention (odds ratio 9.6). Our study showed the excellent immediate outcomes of BPV and DS in a pure cohort of patients with CPS. Prophylactic DS in selected cases seems reasonable and safe.

Transjugular Balloon Pulmonary Valvuloplasty Through a Bidirectional Glenn Shunt for Dysplastic Pulmonary Valve Stenosis in an 8.7-Year-Old Boy with Inaccessible Femoral Veins

An 8.7-year-old boy was affected by exertional dyspnea with cyanosis of the lip at 6 years old. Oxygen saturation (SpO2) was 66%. A bidirectional Glenn shunt (BGS) was constructed to successfully elevate SpO2 to 88%. Unfortunately, he again experienced exertional dyspnea with flagrant cyanosis of the lip at 8.5 years old. SpO2 decreased to 65%. Echocardiography revealed a dysplastic pulmonary valve with severe stenosis. Considering the potential growth of the right ventricle and the branch pulmonary arteries, transjugular balloon pulmonary valvuloplasty (BPV) through a BGS was performed as a palliative treatment for cyanosis in this boy because of inaccessible femoral veins. After gradational BPV, the opening of the pulmonary valve was dilated from 2.59 mm to 6.65 mm, the pressure gradient decreased from 60 mmHg to 25 mmHg, and the SpO2 increased to 85%. He became physically active and was free of exertional dyspnea at the 12-month follow-up. BGS is irrefutably an alternative vascular access through which transjugular BPV could be performed to ameliorate cyanosis due to dysplastic pulmonary valve stenosis in patients with inaccessible femoral vessels.

Radiofrequency applications in congenital heart disease

The relatively recent application of radiofrequency technologies in the treatment of congenital heart defects has provided a safe and effective alternative to conventional therapies in establishing endovascular patency for a variety of lesions. Radiofrequency, with typically used frequencies of approximately 500 kHz, does not cause pain and is unlikely to induce atrial or ventricular fibrillation. It can be used either to ablate (higher power (35-50 W); longer duration of application (90-120 sec); lower voltage (30-50 V)) or to perforate (lower power (5-10 W) shorter duration of application (1-5 sec), higher voltage (150-280 V)). In the past, perforating radiofrequency has been applied to establish right ventricular outflow tract patency in pulmonary atresia with intact septum and with ventricular septal defect. More recently radiofrequency has been shown to be effective at recanalizing central and peripheral vasculature and has also been applied in establishing percutaneous left heart access. A new radiofrequency catheter, dedicated to transseptal left atrial cannulation, has been demonstrated to be safe and effective in an animal model and is now ready for clinical trials.

Outcomes and predictors of reintervention in patients with pulmonary atresia and intact ventricular septum treated with radiofrequency perforation and balloon pulmonary valvuloplasty

Radiofrequency perforation and valvuloplasty (RFV) is an effective initial treatment in patients with pulmonary atresia and intact ventricular septum (PA-IVS) and mild to moderate right ventricle and tricuspid valve hypoplasia. Outcomes and risk factors for the need for additional interventions in these patients are poorly defined. All patients with PA-IVS who underwent RFV at our center between January 2000 and July 2011 were reviewed. Twenty-three patients met the inclusion criteria. All patients underwent successful valvuloplasty with no procedural deaths and one major complication. Excluding two patients with limited follow-up, 6 (29 %) patients underwent no subsequent interventions, whereas 9 (42 %) patients underwent surgical right-ventricular outflow tract augmentation. All except one patient with adequate follow-up have a biventricular circulation with saturation >92 %. Patients who did not undergo any right-ventricular outflow tract intervention after valvuloplasty had a significantly lower gradient across the pulmonary valve after valvuloplasty (9.9 mmHg ± 8.4 vs. 19.1 mmHg ± 10.4, p = 0.05). Significantly more patients who received a supplemental source of pulmonary blood flow had a tricuspid valve z-score <-0.7 compared with patients who did not receive supplemental blood flow [2 (15 %) vs. 7 (70 %), p = 0.008]. In our cohort of patients with PA-IVS, radiofrequency perforation with valvuloplasty was an effective and safe first step in establishing a biventricular circulation. Postvalvuloplasty pulmonary valve gradient may be predictive of subsequent outflow tract intervention, and tricuspid hypoplasia may be predictive of the need for a supplemental source of pulmonary blood flow.

Transcatheter management of neonates with pulmonary atresia with intact ventricular septum: a single center experience from Turkey

Pulmonary atresia with intact ventricular septum (PAIVS) is characterized by a broad spectrum of heterogeneous morphologies. Perforation of the atretic valve, balloon dilatation, and stenting of the patent ductus arteriosus are the percutaneous techniques that are used with increasing frequency in our clinic as well. They have some advantages over surgery, including short hospital stay and short intensive care unit stay. The main goal of the primary interventional approach is to avoid surgery. However, a group of patients with PAIVS still need surgery due to poor right ventricular growth. Therefore, the final achievement of the initial percutaneous treatment strategies is still debatable. In this article, we present the early- and mid-term results of the percutaneous approach utilized at our clinic in order to investigate the final effects of interventional therapy according to initial morphology. Between May 2010 and May 2012, 15 neonates diagnosed with PAIVS underwent transcatheter intervention. Detailed echocardiographic examination focused on right ventricle size, and tricuspid valve morphology and coronary sinusoids were performed in all the patients before the intervention. Nine of the patients were boys and six were girls. The mean age was 11.40 ± 12.87 days and mean weight was 3.34 ± 0.46 kg. Only one procedure-related mortality occurred. The mean follow-up period was 10.05 ± 3.42 months (1-26 months). The mean duration of intensive care was 7.19 ± 5.14 days. The mean follow-up time was 10.05 ± 3.42 months. After this period, survival rate was 66% (10/15). Two of the patients achieved biventricular physiology after pulmonary valve perforation. Two patients still have univentricular physiology. Six patients have been followed as a one and half ventricle repair candidate. Five out of 15 patients had stent patency during 6 months of follow-up, while restenosis developed in one patient (1/5, 20%), who had undergone the Glenn operation at 5 months of age. Transcatheter management for PAIVS is a feasible, safe, and effective primary palliative treatment in newborns. Shunt surgery may be considered in cases where cyanosis occurs despite transcatheter intervention. Right ventricular size determines the type of intervention. The early outcomes can be comparable with surgical palliation. However, a group of PAIVS, particularly with severe right ventricular hypoplasia, needs surgery even after a successful primary percutaneous intervention.

Catheter-based treatment in patients with critical pulmonary stenosis or pulmonary atresia with intact ventricular septum: a single institute experience with comparison between patients with and without additional procedure for pulmonary flow

OBJECTIVES

We report a single institute experience of transcatheter pulmonary valvotomy using the soft end of a guidewire followed or not by a systemic-pulmonary shunt in patients with pulmonary atresia with intact ventricular septum (PAIVS) or critical pulmonary stenosis (CPS). In addition, we compare patients with or without an additional source of flow to support the pulmonary circulation after successful pulmonary valvotomy.

METHODS

All neonates with PAIVS or CPS who underwent primary transcatheter pulmonary valvotomy between January 2004 and December 2010 were reviewed retrospectively. Some of them needed an additional source of flow to support the pulmonary circulation. We performed a comparison between those who required an additional source of pulmonary flow and those who did not.

RESULTS

The initial procedure was successful in 20 out of 22 patients (seven of nine with PAIVS; all of 13 with CPS), but 10 of them needed an additional source of flow to support the pulmonary circulation: nine had arterial duct stenting and one had surgical Blalock-Taussig shunt. There were no deaths or major acute complications, except for femoral artery occlusion in three patients. The bipartite right ventricular morphology, the tricuspid z-score of ≤-0.74, the tricuspid to mitral valve ratio of ≤ 0.9, and the z-score of the diastolic interventricular septal thickness ≥ 2.37 in preprocedural examination showed more tendency of needing shunt placement.

CONCLUSION

Transcatheter pulmonary valvotomy using the soft end of a guidewire followed or not by the arterial duct stent implantation was an effective approach in those patients. The angiographic distinction between CPS and PAIVS did not affect anything in this study including the procedural method, success, and odds for reintervention. The degree of right ventricle cavity hypoplasia provided the main restriction to forward flow after pulmonary valvotomy.

Pulmonary atresia with intact septum: the use of Conquest Pro coronary guidewire for perforation of atretic valve and subsequent interventions

OBJECTIVE

To determine the feasibility and safety of the Conquest Pro wire as an alternative to radiofrequency wire for perforation of atretic pulmonary valve and subsequent balloon dilatation and patent ductus arteriosus stenting in patients with pulmonary atresia with intact ventricular septum.

BACKGROUND

Radiofrequency valvotomy and balloon dilatation has become the standard of care for pulmonary atresia with intact ventricular septum in many institutions today.

METHODS

We report eight consecutive patients in whom we used the Conquest Pro coronary guidewire, a stiff wire normally reserved for revascularisation of coronary lesions with chronic total occlusion, for perforation of atretic pulmonary valve and subsequent balloon dilatation, and stenting of the patent ductus arteriosus.

RESULTS

Perforation of atretic pulmonary valve was successful in seven out of eight cases. Radiofrequency valvotomy was employed after failure of perforation by the Conquest Pro wire in one case where the right ventricular outflow tract was broad based and tapered towards the pulmonary valve, and was heavily trabeculated. Failure of the Conquest Pro wire to perforate the pulmonary valve plate was mainly attributed by the failure to engage the wire at the correct position.

CONCLUSION

The Conquest Pro wire for perforation and subsequent interventions in the more straightforward cases of pulmonary atresia with intact ventricular septum is effective and safe, simplifying the entire procedure. However, the radiofrequency generator and wires remain essential tools in the paediatric interventional catheter laboratory.

Stenting of Lesions in Patent Ductus Arteriosus with Duct-Dependent Pulmonary Blood Flow: Focus on Case Selection, Techniques and Outcome

Stenting of patent ductus arteriosus (PDA) is an attractive alternative to the surgical aortopulmonary shunt in the palliation of cyanotic congenital heart disease. However, the diverse morphology of PDA in this setting limits its role, as stenting an overly tortuous duct may not be feasible, and in a significant number of patients, ductus-related pulmonary artery stenosis contraindicates this procedure. The major acute complications are stent migration, thrombosis, and cardiac failure. Early failure of palliation caused by in-stent stenosis is another limitation of this procedure.

Decreased incidence of right-ventricular outflow tract complications using a retrograde snare technique for radiofrequency pulmonary valve perforation

Perforation of the atretic pulmonary valve with balloon dilation in infants with pulmonary atresia with intact ventricular septum (PA-IVS) is standard initial therapy for right-ventricular (RV) decompression. This procedure often results in adequate pulmonary blood flow, thus eliminating the need for neonatal surgery. Nonetheless, the incidence of RV outflow-tract complications and mortality for this intervention is significant. We report our experience with retrograde snare-guided radiofrequency (RF) perforation in an attempt to improve accuracy and decrease procedural complications. Medical records were reviewed for the period between March 2007 and May 2010 for all patients with PA-IVS who presented to the catheterization laboratory for attempted RF perforation in infancy. Specific details reviewed included demographics, preprocedural echocardiographic (echo) data, procedural technique and complications, pre- and post-RV pressures and pulmonary valve gradients, need for surgical intervention in the neonatal period, and short- to medium-term follow-up. Eleven neonates with PA-IVS underwent RF perforation using a retrograde snare-guided technique during the study period. The pulmonary valve was successfully perforated and the wire snared in all 11 patients. Six of 11 atretic valves were crossed on the first attempt with low energy (5 W × 2 s). No episodes of tamponade or RV/PA perforation occurred as confirmed by echocardiogram performed immediately after the procedure. There was no ductal spasm with retrograde catheter manipulations. Sequential dilation of the perforated valve was not necessary. RV pressures decreased from 169 % systemic before dilation to 93 % after dilation (p < 0.001) with a residual pulmonary valve gradient of 16 ± 6 mm Hg. Eight of 11 patients (73 %) were discharged without surgery at an average 16 days after the intervention. Three patients required Blalock-Taussig shunts to augment pulmonary blood flow. Femoral artery thrombus occurred in 4 of 11 patients treated with anticoagulation, and 2 patients had atrial arrhythmias during the procedure. No other complications occurred. No preprocedural echo parameters predicted requirement for surgical shunt before hospital discharge. Retrograde snare-guided pulmonary valve perforation in infants with PA-IVS is safe and may decrease the incidence of significant procedural complications.

Outcomes of transcatheter approach for initial treatment of pulmonary atresia with intact ventricular septum

OBJECTIVE

To review the short and medium term outcome of transcatheter pulmonary valve perforation (PVP) in patients with pulmonary atresia-intact ventricular septum and non-right ventricular dependant coronary circulation (PA/IVS non-RVDCC).

BACKGROUND

PVP in patients with PA/IVS non-RVDCC has become more common in the past two decades. However, data on outcomes with this strategy are mixed.

METHODS

Data were reviewed retrospectively for all patients with PA/IVS non-RVDCC treated from 1996- 2010 at our institution. Patients who had severe neonatal Ebstein malformation, or initial interventional management at another institution were excluded.

RESULTS

PVP was attempted in 30 of 50 patients (60%); 26 (87%) of these had a successful procedure. Twenty-four patients (48%) had surgery without PVP. There were no deaths in the cohort. Complications of PVP included 5 (17%) myocardial perforations. Of those with successful PVP, 10 (38%) did not have surgery (PVP-NS) and 16 (62%) had surgery (PVP-S) prior to discharge. Tricuspid valve (TV) Z-score was larger in the PVP-NS than in PVP-S patients, with median TV diameter Z-scores of +0.7 (-0.9, 1.7) and -1.1 (-2.8, 2), respectively (P = 0.01). Time from PVP to either hospital discharge (PVP-NS group) or surgery (PVP-S group) was significantly different between groups: 15 (7, 22) and 8 days (0, 46), respectively (P = 0.01). There were no differences in the number of trials or lowest arterial PaO2 off prostaglandins between groups. All patients in the PVP-NS group had a biventricular circulation at a median follow-up of 4.3 years.

CONCLUSIONS

The results of a collaborative approach to treating neonates with PA/IVS non-RVDCC are excellent. Smaller TV size is associated with greater likelihood of surgery prior to discharge, and may serve as a surrogate for early RV inadequacy.

Fetal intervention in right outflow tract obstructive disease: selection of candidates and results

Objectives. To describe the process of selection of candidates for fetal cardiac intervention (FCI) in fetuses diagnosed with pulmonary atresia-critical stenosis with intact ventricular septum (PA/CS-IVS) and report our own experience with FCI for such disease. Methods. We searched our database for cases of PA/CS-IVS prenatally diagnosed in 2003–2012. Data of 38 fetuses were retrieved and analyzed. FCI were offered to 6 patients (2 refused). In the remaining it was not offered due to the presence of either favourable prognostic echocardiographic markers (n = 20) or poor prognostic indicators (n = 12). Results. The outcome of fetuses with PA/CS-IVS was accurately predicted with multiparametric scoring systems. Pulmonary valvuloplasty was technically successful in all 4 fetuses. The growth of the fetal right heart and hemodynamic parameters showed a Gaussian-like behaviour with an improvement in the first weeks and slow worsening as pregnancy advanced, probably indicating a restenosis. Conclusions. The most likely type of circulation after birth may be predicted in the second trimester of pregnancy by means of combining cardiac dimensions and functional parameters. Fetal pulmonary valvuloplasty in midgestation is technically feasible and in well-selected cases may improve right heart growth, fetal hemodynamics, and postnatal outcome.

Stenting the patent ductus arteriosus in duct-dependent pulmonary circulation: techniques, complications and follow-up issues

Maintaining ductal patency in duct-dependent congenital heart lesions by implantation of coronary stents is an alternative to systemic pulmonary shunt in selected cases and lesions with suitable anatomy. This article focuses on the procedure as the initial palliation in duct-dependent pulmonary circulation, its associated pitfalls and complications. A good understanding of the diverse duct morphology is paramount prior to stenting of the ductus. Long tortuous duct, insufficiently constricted ductus at the pulmonary end and ductus with associated branch pulmonary artery stenosis at the site of insertion are not suitable for stenting. Durability of palliation is generally inferior to a surgical shunt and this may dictate earlier definitive surgical repair. Acceleration of branch pulmonary artery stenosis in certain ductal morphology limits its general applicability. Bioabsorbable and biodegradable stents may offer some solution to this problem.

A new endovascular radiofrequency device for dilatation of vascular stenosis in a rabbit model

PURPOSE

To investigate the use of a new endovascular radiofrequency (RF) device, the Habib™ VesCoag™ Catheter, to induce vascular remodeling and dilatation of arterial stenosis in a rabbit model.

MATERIALS AND METHODS

RF was used to induce arterial stenosis in 10 rabbits and this was confirmed by angiography and color Doppler ultrasound. Two groups of five animals were then subjected to (1) balloon dilatation of the stenosis (intervention group), (2) no intervention (control group). Two rabbits from each group were sacrificed following the procedures to investigate vessel histopathology. At six weeks, the remaining six rabbits underwent follow-up angiogram and color Doppler ultrasound to assess vessel patency. They were then sacrificed and the vessels prepared for histopathological analysis. Three-dimensional images with confocal microscopy of the arterial lumen were also acquired.

RESULTS

In the intervention group, stenosis was reversed and patency confirmed by angiography and color Doppler ultrasound six weeks later in all surviving rabbits. Histopathology revealed degenerative changes of elastic fibers, focal losses of elastica lamella, disorganization of myocytes and extensive hyalinization of the tunica adventitia. Focal elastin changes of the arterial elastic lamella were also shown by three-dimensional confocal microscopy images.

CONCLUSION

We have developed a novel endovascular RF catheter that can be safely and effectively used to induce vascular remodeling and dilatation of arterial stenosis in an experimental rabbit model.

Restrictive right ventricular physiology and right ventricular fibrosis as assessed by cardiac magnetic resonance and exercise capacity after biventricular repair of pulmonary atresia and intact ventricular septum

BACKGROUND

The hypertrophic myocardium, myocardial fiber disarray, and endocardial fibroelastosis in pulmonary atresia and intact ventricular septum (PAIVS) may provide anatomic substrates for restrictive filling of the right ventricle.

HYPOTHESIS

Restrictive right ventricle (RV) physiology is related to RV fibrosis and exercise capacity in patients after biventricular repair of PAIVS.

METHODS

A total of 27 patients, age 16.5 +/- 5.6 years, were recruited after biventricular repair of PAIVS. Restrictive RV physiology was defined by the presence of antegrade diastolic pulmonary flow and RV fibrosis assessed by late gadolinium enhancement (LGE) cardiac magnetic resonance. Their RV function was compared with that of 27 healthy controls and related to RV LGE score and exercise capacity.

RESULTS

Compared with controls, PAIVS patients had lower tricuspid annular systolic and early diastolic velocities, RV global longitudinal systolic strain, systolic strain rate, and early and late diastolic strain rates (all P < 0.05). A total of 22 (81%, 95% confidence interval: 62%-94%) PAIVS patients demonstrated restrictive RV physiology. Compared to those without restrictive RV physiology (n = 5), these 22 patients had lower RV global systolic strain, lower RV systolic and early diastolic strain rates, higher RV LGE score, and a greater percent of predicted maximum oxygen consumption (all P < 0.05).

CONCLUSION

Restrictive RV physiology reflects RV diastolic dysfunction and is associated with more severe RV fibrosis but better exercise capacity in patients after biventricular repair of PAIVS.

Critical care outcomes in pulmonary atresia and intact ventricular septum undergoing single-ventricle palliation

OBJECTIVE

To examine early outcomes for pulmonary atresia with intact ventricular septum undergoing single-ventricle palliation and to determine risk factors for mortality.

DESIGN

Retrospective observational study.

SETTING

Tertiary paediatric critical care unit.

INTERVENTION

Risk factors for mortality were sought for infants after the primary intervention whether surgical shunt or ductal stent.

MEASUREMENTS AND MAIN RESULTS

We reviewed outcomes of 19 infants with pulmonary atresia with intact ventricular septum undergoing single-ventricle palliation between July, 2000 and July, 2008. Echocardiograms, cardiac catheterisation findings, anaesthesia, and critical care management, as well as autopsy reports were reviewed. We modelled survival after surgery and looked for predictors of early mortality. A total of 19 infants underwent single-ventricle palliation and seven of these died. The risk of death was increased by a lower arterial pH at induction of anaesthesia (p = 0.01), a lower systolic blood pressure (p = 0.01), and technical problems during surgery (p = 0.03). On admission to the critical care unit, a lower mixed venous saturation (p = 0.02) and presence of tachyarrhythmia (p = 0.02) were associated with the need for mechanical support within the first 48 hours.

CONCLUSIONS

There is a high early mortality for those who undergo single-ventricle palliation. It is higher for those who are haemodynamically compromised before surgery; technical problems, and haemodynamic instability during surgery also increase mortality.