Radiofrequency perforation of the right ventricular outflow tract as a palliative strategy for pulmonary atresia with ventricular septal defect

Retrograde Pulmonary Valve Perforation and Stenting through a Major Aorto-Pulmonary Collateral Artery

Management of pulmonary atresia, ventricular septal defect with major aorto-pulmonary collateral arteries, and hypoplastic native pulmonary arteries focuses on growth of the native pulmonary arteries. One strategy to grow the native pulmonary arteries is through pulmonary valve perforation followed by right ventricular outflow tract stenting, if suitable. We present a unique case of retrograde pulmonary valve perforation and stenting of the right ventricular outflow tract through a major aorto-pulmonary collateral artery.

Optimal management of pulmonary atresia with intact ventricular septum in a developing country: the art of pulmonary valve mechanical perforation in the era of CTO hardware

BACKGROUND

Transcatheter valve mechanical perforation (TVMP) in pulmonary atresia with intact ventricular septum (PAIVS) is an acceptable yet challenging alternative to radiofrequency.

AIMS

To evaluate and compare safety, feasibility, and efficiency of two TVMP techniques.

METHODS

Clinical data of neonates with PAIVS who underwent an attempt for TVMP between 2009 and 2019 were retrospectively reviewed. Patients were divided into two groups according to perforation technique: using the stiff end of a percutaneous transluminal coronary angioplasty (PTCA) ordinary 0.014" wire (group A) and subsequently with the floppy tip of a chronic total occlusion (CTO) guidewire (group B). The technical aspects, procedural and discharge outcomes of both groups were compared.

RESULTS

A total of 19 antegrade TVMP procedures (Group A, n=10, and Group B, n=9) were attempted in 18 neonates with an overall success rate of 73.7% and no procedure-related mortality. Groups' analysis showed that the introduction of CTO hardware maximized procedure success rates (P=0.002) with zero failure and misperforations (P=0.022). The significant drop in perforation time (P < 0.001) and irradiation exposure (P=0.006) allowed additional ductal stenting during the same procedure, optimizing patients' clinical outcomes and shortening overall hospital stay. Discharged patients had room air mean oxygen saturation of 91.4% (± 5.5) with no evidence of heart failure.

CONCLUSIONS

In selected cases of PAIVS, TVMP using CTO wires is a safer, highly efficient, and simplified alternative to other mechanical perforation techniques. It substantially revolutionized the management of PAIVS in our center optimizing short-term prognosis.

Hybrid procedure of right ventricle outflow tract stenting in small infants with pulmonary atresia and ventricular septal defect: early and mid-term results from a single centre

IntroductionPulmonary atresia, ventricular septal defect, major aorto-pulmonary collateral arteries, and pulmonary arteries hypoplasia are rare and complex congenital defects that require early interventions to relieve cyanosis and enhance the growth of native pulmonary arteries. The treatment of these patients is still controversial. Surgical techniques require cardiopulmonary bypass which is poorly tolerated by small infants. Percutaneous techniques such as radiofrequency perforation can be challenging. The hybrid technique consists of perventricular stenting of the right ventricle outflow tract through medial sternotomy, to restore native pulmonary flow.

METHODS

We retrospectively reviewed the cardiovascular database of our centre in order to analyse our experience in hybrid procedure. We detected six patients who underwent hybrid first approach between November 2007 and December 2015. We report our early results and mid-term outcomes.

RESULTS

Median age at the procedure was 26 days, median weight was 3150 g, and median Nakata index was 52 mm2/m2. All procedures were successful except for one: this patient underwent a surgical shunt. No immediate and early deaths or major complications occurred and oxygen saturation levels increased in all the patients. Patients were followed up for a period of 12-103 months, and four of them underwent a procedure of unifocalisation at the mean age of 12.5 months.

CONCLUSIONS

We reported data from the largest series of patients who underwent this hybrid procedure. Our experience demonstrated encouraging results to expand the use of this approach to bridge high-risk patients with diminutive pulmonary arteries to a second step of surgical repair.

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.

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.

Transcatheter perforation followed by pulmonary valvuloplasty in neonates with pulmonary atresia and ventricular septal defect

BACKGROUND

The classic management of neonates with pulmonary atresia with ventricular septal defect (PAVSD) and moderately hypoplastic pulmonary arteries is usually a systemic to pulmonary artery shunt or ductus arteriosus stenting. We report our experience of transcatheter treatment of PAVSD by perforation followed by balloon dilation of the valve, as it is performed in pulmonary atresia - intact ventricular septum.

PATIENTS AND METHOD

Three patients were treated at a mean age and weight of 7.5 days (range 7-8) and 2.9kg (range 2.5-3.3), respectively. Two newborns were prenatally diagnosed, with micro deletion 22q11 in one case. The three patients had no other pulmonary blood flow support than the ductus arteriosus and were on prostaglandin E1 infusion. The pulmonary atresia was predominantly valvular without significant muscular obstruction. By echocardiography, the mean size of the pulmonary annulus was 6.5mm (range 6-7). In all cases, the valvular perforation was performed with a 0.014 coronary guidewire, followed by balloon dilation when successfully.

RESULTS

The procedure succeeded in two cases but failed in the third newborn in whom a long subvalvar muscular stenosis was found at surgery. In the two successful cases, the mean postprocedural transpulmonary doppler gradient was 33.5mmHg (range 17-50). One patient experienced a femoral venous thrombosis that was successfully treated by heparin and a transient right bundle branch block occurred in another one. In the two successful cases, the prostaglandin E1 infusion was weaned and the surgical repair was performed at 4 and 12 months, respectively.

CONCLUSION

In selected cases with PAVSD, perforation followed by balloon dilation of the pulmonary valve offers an interesting alternative to other surgical or transcatheter palliative therapies.

Creation of transcatheter aortopulmonary and cavopulmonary shunts using magnetic catheters: feasibility study in swine

Surgical shunts are the basic form of palliation for many types of congenital heart disease. The Glenn shunt (superior cavopulmonary connection) and central shunt (aortopulmonary connection) represent surgical interventions that could potentially be accomplished by transcatheter techniques. We sought to investigate the efficacy of using neodymium iron boron (NdFeB) magnetic catheters to create transcatheter cavopulmonary and aortopulmonary shunts. NdFeB magnets were machined and integrated into catheters. "Target" catheters were placed in the pulmonary arteries (PAs), and radiofrequency "perforation" catheters were placed in either the descending aorta (DAo) for central shunts or the superior vena cava (SVC) for Glenn shunts. The magnet technique or "balloon target" method was used to pass wires from the DAo or the SVC into the PA. Aortopulmonary and cavopulmonary connections were then created using Atrium iCAST covered stents. Magnet catheters were used to perforate the left pulmonary artery from the DAo, thereby establishing a transcatheter central shunt. Given the orientation of the vasculature, magnetic catheters could not be used for SVC-to-PA connections; however, perforation from the SVC to the right pulmonary artery was accomplished with a trans-septal needle and balloon target. Transcatheter Glenn or central shunts were successfully created in four swine.

[Update on pediatric cardiology and congenital heart disease]

The fields of pediatric cardiology and congenital heart disease have experienced considerable progress in the last few years, with advances in new diagnostic and therapeutic techniques that can be applied at all stages of life from the fetus to the adult. This article reviews scientific publications in a number of areas that appeared between August 2007 and September 2008. In developed countries, congenital heart disease is becoming increasingly prevalent in nonpediatric patients, including pregnant women. Actions aimed at preventing coronary heart disease must be started early in infancy and should involve the promotion of a healthy diet and lifestyle. Recent developments in echocardiography include the introduction of three-dimensional echocardiography and of new techniques such as two-dimensional speckle tracking imaging, which can be used for both anatomical and functional investigations in patients with complex heart disease, including a univentricular heart. Progress has also occurred in fetal cardiology, with new data on prognosis and prognostic factors and developments in intrauterine interventions, though indications for these interventions have still to be established. Heart transplantation has become a routine procedure, supplemented in some cases by circulatory support devices. In catheter interventions, new devices have become available for the closure of atrial or ventricular septal defects and patent ductus arteriosus as well as for percutaneous pulmonary valve implantation. Surgery is also advancing, in some cases with hybrid techniques, particularly for the treatment of hypoplastic left heart syndrome. The article ends with a review of publications on cardiomyopathy, myocarditis and the treatment of bacterial endocarditis.

The role of stents in the treatment of congenital heart disease: Current status and future perspectives

Intravascular or intracardiac stenoses occur in many forms of congenital heart disease (CHD). Therefore, the implantation of stents has become an accepted interventional procedure for stenotic lesions in pediatric cardiology. Furthermore, stents are know to be used to exclude vessel aneurysm or to ensure patency of existing or newly created intracardiac communications. With the further refinement of the first generation of devices, a variety of "modern" stents with different design characteristics have evolved. Despite the tremendous technical improvement over the last 20 years, the "ideal stent" has not yet been developed. Therefore, the pediatric interventionalist has to decide which stent is suitable for each lesion. On this basis, currently available stents are discussed in regard to their advantages and disadvantages for common application in CHD. New concepts and designs developed to overcome some of the existing problems, like the failure of adaptation to somatic growth, are presented. Thus, in the future, biodegradable or growth stents might replace the currently used generation of stents. This might truly lead to widening indications for the use of stents in the treatment of CHD.