Growth of the right ventricle after successful transcatheter pulmonary valvotomy in neonates and infants with pulmonary atresia and intact ventricular septum

Fetal Pulmonary Valvuloplasty in Fetuses with Right Ventricular Outflow Tract Obstructive Disease: Experience and Outcome of the First Five Cases in China

The current study was to report our initial experiences of fetal pulmonary valvuloplasty (FPV) for fetuses with pulmonary atresia with intact ventricular septum (PA/IVS) and critical pulmonary stenosis (CPS), including case selection, technical feasibility, and the effects of FPV on utero and postnatal outcome. Two fetuses with PA/IVS and three fetuses with CPS were enrolled between September 2016 and April 2018. All fetuses were with concomitant severe right ventricular dysplasia and growth arrest. Parameters of right cardiac development and hemodynamics, including tricuspid/mitral annulus ratio (TV/MV), right ventricle/left ventricle long-axis ratio (RV/LV), tricuspid valve inflow duration/cardiac cycle ratio (TVI/CC), degree of tricuspid regurgitation (TR), and blood flow direction of arterial duct and ductus venosus, were evaluated using echocardiogram. FPV was performed trans-abdominally under ultrasound guidance. Echocardiogram was performed post-FPV and every 2-4 weeks thereafter until delivery. The median gestational age at the time of FPV was 28 weeks. From technical perspective, pulmonary balloon valvuloplasty was successfully performed and the opening of pulmonary valve was improved in all fetuses in 2-4 weeks. However, progressive restenosis was observed in four fetuses with gestation advancing, and re-atresia occurred in two PA/IVS fetuses at 36th and 37th weeks' gestation, respectively. The growth trajectories of TV/MV, RV/LV, and TVI/CC were improved in the 1st week after FPV and then slowed down along with pulmonary valve restenosis. All fetuses were born alive and underwent postnatal interventions, including pulmonary balloon valvuloplasty in three fetuses and surgical procedures in two fetuses. During follow-up, three fetuses turned to be biventricular, one became one and a half ventricular at 1-year old, and one died of neonatal infection. Although pulmonary valve restenosis might occur as gestation advancing, FPV seems to be a safe and feasible procedure to improve the growth trajectories of right heart for fetuses with PA/IVS and CPS.

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.

Hybrid Approach to Right Ventricle Decompression in Muscular Pulmonary Atresia with Intact Ventricular Septum

Muscular pulmonary atresia with intact ventricular septum (PA/IVS) in neonates is traditionally managed by surgery. We describe hybrid approach to decompress the right ventricle (RV) and establish RV to pulmonary artery connection in a neonate avoiding cardiopulmonary bypass. A 21-gauge access needle was used to perforate the atretic pulmonary valve via periventricular approach followed by stent placement. This case is an example of how patients with congenital heart disease can be palliated in creative ways through thoughtful collaboration between surgical and interventional cardiology teams.

Fetal Cardiac Intervention for Pulmonary Atresia with Intact Ventricular Septum: International Fetal Cardiac Intervention Registry

INTRODUCTION

Invasive fetal cardiac intervention (FCI) for pulmonary atresia with intact ventricular septum (PAIVS) and critical pulmonary stenosis (PS) has been performed with small single-institution series reporting technical and physiological success. We present the first multicenter experience.

OBJECTIVES

Describe fetal and maternal characteristics of those being evaluated for FCI, including pregnancy/neonatal outcome data using the International Fetal Cardiac Intervention Registry (IFCIR).

METHODS

We queried the IFCIR for PAIVS/PS cases evaluated from January 2001 to April 2018 and reviewed maternal/fetal characteristics, procedural details, pregnancy and neonatal outcomes. Data were analyzed using standard descriptive statistics.

RESULTS

Of the 84 maternal/fetal dyads in the registry, 58 underwent pulmonary valvuloplasty at a median gestational age of 26.1 (21.9-31.0) weeks. Characteristics of fetuses undergoing FCI varied in terms of tricuspid valve (TV) size, TV regurgitation, and pulmonary valve patency. There were fetal complications in 55% of cases, including 7 deaths and 2 delayed fetal losses. Among those who underwent successful FCI, the absolute measurement of the TV increased by 0.32 (±0.17) mm/week from intervention to birth. Among 60 liveborn with known outcome, there was a higher percentage having a biventricular circulation following successful FCI (87 vs. 43%).

CONCLUSIONS

Our data suggest a possible benefit to fetal therapy for PAIVS/PS, though rates of technically unsuccessful procedures and procedure-related complications, including fetal loss were substantial. FCI criteria are extremely variable, making direct comparison to nonintervention patients challenging and potentially biased. More uniform FCI criteria for fetuses with PAIVS/PS are needed to avoid unnecessary procedures, expose only fetuses most likely to sustain a benefit, and to enable comparisons to be made with nonintervention patients.

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.

Differences in Right Ventricular Physiologic Response to Chronic Volume Load in Patients with Repaired Pulmonary Atresia Intact Ventricular Septum/Critical Pulmonary Stenosis Versus Tetralogy of Fallot

BACKGROUND

Patients with pulmonary atresia with intact ventricular septum and critical pulmonary stenosis (PAIVS/CPS) have wide variation in right ventricle (RV) size, systolic function, and diastolic function at birth. Establishment of antegrade pulmonary blood flow creates the potential for RV dilation from chronic pulmonary insufficiency. Future surgical decisions are based on RV size and function, largely supported by longitudinal studies of patients with Tetralogy of Fallot (TOF). Given potential differences in RV physiology and lack of similar data in PAIVS/CPS, the objective of this study was to determine differences in RV size, systolic function, and diastolic function between patients with PAIVS/CPS versus TOF.

METHODS

We retrospectively collected cardiovascular magnetic resonance (CMR) data in 27 patients with PAIVS/CPS (ages 13.3 ± 8.8 years) and 78 with TOF (11.4 ± 5.4 years). RV volumes, ejection fraction (EF), regurgitant fraction, end-diastolic forward flow across the pulmonary valve, and right atrial cross-sectional area were calculated.

RESULTS

There was no difference between the groups in RV end-diastolic volume (RVEDVi), RVEF, or pulmonary regurgitation. RVEF tended to decrease in TOF when RVEDVi exceeded 164 ml/m². In PAIVS/CPS, RVEDVi less frequently reached 164 ml/m² and was not associated with RVEF. There was worse RV diastolic dysfunction in PAIVS/CPS, with 1.5 times larger right atrial area and two times higher pulmonary end-diastolic forward flow (p < 0.0001).

CONCLUSIONS

Patients with PAIVS/CPS have similar RV size, systolic function, and pulmonary regurgitation as TOF. However, impaired RV diastolic function may limit extremes of RV dilatation and impact long-term management of PAIVS/CPS.

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.

Echocardiographic parameters associated with biventricular circulation and right ventricular growth following right ventricular decompression in patients with pulmonary atresia and intact ventricular septum: Results from a multicenter study

BACKGROUND

In patients with pulmonary atresia, intact ventricular septum (PA/IVS) following right ventricular (RV) decompression, RV size and morphology drive clinical outcome. Our objectives were to (1) identify baseline and postdecompression echocardiographic parameters associated with 2V circulation, (2) identify echocardiographic parameters associated with RV growth and (3) describe changes in measures of RV size and changes in RV loading conditions.

METHODS

We performed a retrospective analysis of patients who underwent RV decompression for PA/IVS at four centers. We analyzed echocardiograms at baseline, postdecompression, and at follow up (closest to 1-year or prior to Glenn circulation).

RESULTS

Eighty-one patients were included. At last follow-up, 70 (86%) patients had 2V circulations, 7 (9%) had 1.5 ventricle circulations, and 4 (5%) had single ventricle circulations. Follow-up echocardiograms were available in 43 (53%) patients. The majority of patients had improved RV systolic function, less tricuspid regurgitation (TR), and more left-to-right atrial shunting at a median of 350 days after decompression. Multivariable analysis demonstrated that larger baseline tricuspid valve (TV) z-score (P = .017), ≥ moderate baseline TR (P = .045) and smaller baseline RV area (P < .001) were associated with larger increases in RV area. Baseline RV area ≥6 cm² /m² had 93% sensitivity and 80% specificity for identifying patients who ultimately achieved 2V circulation. All patients with RV area ≥8 cm² /m² at follow up achieved 2V circulation. This finding was confirmed in a validation cohort from a separate center (N = 25). Factors associated with achieving RV area ≥8 cm² /m² included larger TV z-score (P = .004), ≥ moderate baseline TR (P = .031), and ≥ moderate postdecompression pulmonary regurgitation (P = .002).

CONCLUSIONS

Patients with PA/IVS and smaller TV annuli are at risk for poor RV growth. Volume-loading conditions signal increased capacity for growth sufficient for 2V circulation.

Immediate effects and outcome of in-utero pulmonary valvuloplasty in fetuses with pulmonary atresia with intact ventricular septum or critical pulmonary stenosis

OBJECTIVE

To assess the immediate effects of fetal pulmonary valvuloplasty on right ventricular (RV) size and function as well as in-utero RV growth and postnatal outcome.

METHODS

Patients with pulmonary atresia with intact ventricular septum (PAIVS) or critical pulmonary stenosis (CPS) who underwent fetal pulmonary valvuloplasty at our center between October 2000 and July 2017 were included. Echocardiographic data obtained before and after the procedure were analyzed retrospectively (median interval after intervention, 1 (range, 1-3) days) for ventricular and valvular dimensions and ratios, RV filling time (duration of tricuspid valve (TV) inflow/cardiac cycle length), TV velocity time integral (TV-VTI) × heart rate (HR) and tricuspid regurgitation (TR) velocity. Longitudinal data were collected from only those fetuses followed up in our center. Outcome was assessed using the scoring system as described by Roman et al. for non-biventricular outcome.

RESULTS

Thirty-five pulmonary valvuloplasties were performed in our institution on 23 fetuses with PAIVS (n = 15) or CPS (n = 8). Median gestational age at intervention was 28 + 4 (range, 23 + 6 to 32 + 1) weeks. No fetal death occurred. Immediately after successful intervention, RV/left ventricular length (RV/LV) ratio (P ≤ 0.0001), TV/mitral valve annular diameter (TV/MV) ratio (P ≤ 0.001), RV filling time (P ≤ 0.00001) and TV-VTI × HR (P ≤ 0.001) increased significantly and TR velocity (P ≤ 0.001) decreased significantly. In fetuses followed longitudinally to delivery (n = 5), RV/LV and TV/MV ratios improved further or remained constant until birth. Fetuses with unsuccessful intervention (n = 2) became univentricular, all others had either a biventricular (n = 15), one-and-a-half ventricular (n = 3) or still undetermined (n = 3) outcome. Five of nine fetuses with a predicted non-biventricular outcome, in which the procedure was successful, became biventricular, while two of nine had an undetermined circulation.

CONCLUSION

In selected fetuses with PAIVS or CPS, in-utero pulmonary valvuloplasty led immediately to larger RV caused by reduced afterload and increased filling, thus improving the likelihood of biventricular outcome even in fetuses with a predicted non-biventricular circulation. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Innovative interventional catheterization techniques for congenital heart disease

Since 1929, when the first cardiac catheterization was safely performed in a human by Dr. Werner Forssmann (on himself), there has been a rapid progression of cardiac catheterization techniques and technologies. Today, these advances allow us to treat a wide variety of patients with congenital heart disease using minimally invasive techniques; from fetus to infants to adults, and from simple to complex congenital cardiac lesions. In this article, we will explore some of the exciting advances in cardiac catheterization for the treatment of congenital heart disease, including transcatheter valve implantation, hybrid procedures, biodegradable technologies, and magnetic resonance imaging (MRI)-guided catheterization. Additionally, we will discuss innovations in imaging in the catheterization laboratory, including 3D rotational angiography (3DRA), fusion imaging, and 3D printing, which help to make innovative interventional approaches possible.

Surgical strategy and outcomes for the delayed diagnosis of pulmonary atresia with intact ventricular septum

BACKGROUND

In the present study, we summarize the experiences and evaluate clinical outcomes for the delayed diagnosis of pulmonary atresia with intact ventricular septum (PAIVS) patients when undergoing an initial visit and diagnosis in our heart center.

METHODS

Fifty-eight cases of delayed diagnosis of PAIVS in patients aged more than 6 months between January 2006 and June 2016 were reviewed in our hospital. The median age at initial diagnosis was 12.2 months (range, 6.1-79.6 months). Forty-five cases eventually reached definitive repair. Survival, risk factors for death, and clinical status after definitive repair were assessed.

RESULTS

Among patients who completed definitive repair, the Fontan procedure was performed in a large proportion of older PAIVS children (42.2%, 19/45), while only a few patients received biventricular repair (22.2%, 10/45). The medium-term (10-year) survival rates of biventricular repair, 1.5-ventricular repair, and univentricular palliation were 100.0%, 93.3%, and 81.2%, respectively. At the latest follow-up, most patients had a good clinical status after definitive repairs, with a low re-operation rate.

CONCLUSIONS

A large proportion of the delayed diagnosis of PAIVS patients had to receive univentricular palliation because of limited potential for right ventricular growth. However, optimal definitive repairs could also have been achieved in these patients with a low mortality rate.

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.

Right Ventricular Outflow Tract Obstruction: Pulmonary Atresia With Intact Ventricular Septum, Pulmonary Stenosis, and Ebstein's Malformation

OBJECTIVES

The objectives of this review are to discuss the anatomy, pathophysiology, clinical course, and current treatment strategies for pulmonary atresia with intact ventricular septum, pulmonary stenosis, and Ebstein's anomaly.

DATA SOURCE

MEDLINE and PubMed.

CONCLUSIONS

Considerable advances have been made in management strategies for these complex congenital heart lesions, which have led to improved outcomes.

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.

Fetal cardiac interventions: rationale, risk and benefit

Fetal congenital heart disease may progress during pregnancy and may lead to irreversible myocardial or pulmonary damage. The rationale of fetal intracardiac interventions is to change fetal hemodynamics, prevent secondary damage and improve long-term outcome at an acceptable risk for mother and fetus. This review focuses on the current experience about patient selection, risks and benefits of this technique.

Balloon valvuloplasty through the right ventricle: another treatment of pulmonary atresia with intact ventricular septum

BACKGROUND

This was a study to evaluate the safety and feasibility of balloon valvuloplasty of the pulmonary valve through the right ventricle (RV) for the treatment of pulmonary atresia with intact ventricular septum (PA-IVS).

METHODS

Ten neonates with PA-IVS, who underwent balloon valvuloplasty of the pulmonary valve through the RV at our institution from January 2008 to May 2010, were enrolled in this study. The oxygen saturation range was 60% to 83% (median 76%). The Z-value range of the tricuspid valve annulus was -2 to 2 (median 0.15), the diameter range of the pulmonary valve annulus was 4.6 to 8.6 mm (median 7.3), and the RV systolic pressure range was 88 to 124 mm Hg (median 106.5). A guidewire was used to perforate the pulmonary valve through the RV, followed by balloon dilation of the valve. The procedure was guided by transesophageal echocardiography.

RESULTS

The procedure was carried out successfully in all patients. The procedure time ranged from 64 to 110 minutes (median 82.5). Mechanical ventilation time ranged from 8 to 36 hours (median 11), and hospital stay ranged from 7 to 13 days (median 9). After the procedure, the median oxygen saturation increased to 89.5%, the median RV systolic pressure decreased to 45 mm Hg, and the gradient across the pulmonary valve ranged from 20 to 45 mm Hg (median 27.5). Minor complications included transient supraventricular tachycardia (n = 1), blood loss requiring transfusion (n = 2), moderate pulmonary regurgitation (n = 1), and mild pulmonary regurgitation (n = 3). There were no cases of cardiac perforation, main pulmonary artery aneurysm, or low output syndrome. Follow-up of patients ranged from 8 to 15 months (median 12.3). All patients remained clinically well.

CONCLUSIONS

Balloon valvuloplasty of the pulmonary valve through the RV is a safe and feasible alternative to surgical valvotomy or percutaneous balloon dilation. Early results are encouraging.

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.

Severe aortic or pulmonary valve stenosis in premature infants

Successful treatment of severe aortic (AS) or pulmonary valve (PS) stenosis by balloon valvuloplasty in term neonates is well-established. Sometimes, AS or PS diagnosed antenatally, progresses to severe left or right ventricular hypoplasia respectively. Successful fetal balloon valvuloplasty cannot be assumed to significantly change the natural history. In this review of premature infants, balloon valvuloplasty was used in extremely small babies. Five with severe AS (32 to 36 weeks, birth weight 1.4 to 1.9 kg) had percutaneous balloon aortic valvuloplasty during the first 10 days of life. Seven infants with severe/critical PS (28 to 36 weeks, birth weight 1.2 to 1.9 kg) had percutaneous balloon pulmonary valvuloplasty during the first 9 days of life. Two with pulmonary atresia (1.9 and 0.85 kg), underwent successful radiofrequency assisted balloon pulmonary valvuloplasty. There were no procedural deaths but one infant developed severe aortic insufficiency.

Impact of prenatal diagnosis on outcome of pulmonary atresia and intact ventricular septum

OBJECTIVES

To determine the impact of fetal echocardiography on the management of pregnancy and of newborns affected by pulmonary atresia and intact ventricular septum (PAIVS) and to evaluate the outcome of infants with and without prenatal diagnosis of PAIVS.

METHODS

We searched our database for cases of PAIVS prenatally and postnatally diagnosed during the period January 1993-December 2009. Postnatal follow-up was available in all cases included in the study. Karyotyping and fluorescent in situ hybridization analysis for the DiGeorge critical region (22q11.2) were performed in all but one case.

RESULTS

The study comprised 60 cases of PAIVS: 36 with (Group A) and 24 without (Group B) prenatal diagnosis. In Group A, there were two intrauterine deaths, six postnatal deaths (five early after birth) and one termination of pregnancy. In this group, radiofrequency (RF) perforation was successfully performed in 25 cases; 20/25 infants had a biventricular (BV) repair, without further operation in 13 of them. No patient of Group B died. In this group, RF perforation was successfully performed in 22 cases; 20/22 had a BV repair without further procedure in 15 of them.

CONCLUSIONS

Prenatal diagnosis of PAIVS allows a reliable prognosis of severity and planning of proper surgical repair strategies. Fetuses that are prenatally diagnosed present a more severe spectrum of the disease; for the cases capable of getting through the neonatal period, the mortality rate and the need for further intervention were not significantly different when compared with babies with only postnatal diagnosis.

Catheter-based therapy for small preterm infants with pulmonary atresia/intact ventricular septum

Catheter-based therapy is the preferred treatment for term infants with pulmonary atresia and intact ventricular septum without right ventricular-dependent coronaries, membranous atresia with patent infundibulum, and acceptable-sized tricuspid valve. However, in smaller preterm infants, it is more difficult to determine the adequacy of the tricuspid valve and right ventricle for two-ventricle repair and there are increased procedural risks. An excellent result in a small preterm infant with pulmonary atresia and intact ventricular septum is described using the following algorithm: determination of the tricuspid/mitral annular ratio, right-sided catheter-based intervention, and a combination of transthoracic echocardiography and angiography.

In utero valvuloplasty for pulmonary atresia with hypoplastic right ventricle: techniques and outcomes

BACKGROUND

Prenatal intervention for fetuses with pulmonary atresia with an intact ventricular septum (PA/IVS) has the potential to alter right heart physiologic features in utero, facilitating right heart growth and improving the prospect of a biventricular outcome after birth.

METHODS

Since 2002, we have considered prenatal intervention for fetal PA/IVS in patients with (1) membranous pulmonary atresia, with identifiable pulmonary valve (PV) leaflets or membrane; (2) an intact or highly restrictive ventricular septum; and (3) right heart hypoplasia, with a tricuspid valve annulus z score of -2 or below and an identifiable but small right ventricle. Intervention was performed through direct cardiac puncture under ultrasound guidance, with percutaneous access or access through a limited laparotomy.

RESULTS

Ten fetuses underwent attempted balloon dilation of the PV in utero. The first 4 procedures were technically unsuccessful, and the most-recent 6 were technically successful. Compared with control fetuses with PA/IVS who did not undergo prenatal intervention and had univentricular outcomes after birth, the tricuspid valve annulus, right ventricle length, and PV annulus grew significantly more from midgestation to late gestation in the 6 fetuses who underwent successful interventions.

CONCLUSIONS

In utero perforation and dilation of the PV in midgestation fetuses with PA/IVS is technically feasible and may be associated with improved right heart growth and postnatal outcomes for fetuses with moderate right heart hypoplasia in midgestation. There is an important learning curve for this procedure, and much remains to be learned about the selection of appropriate fetuses for prenatal intervention.

Potential strategies for myocardial regeneration in pediatric patients

Owing to the heart’s limited ability for self-repair, heart failure is a leading cause of death among all patient populations. Thus, a cell-based regenerative strategy for cardiac repair would be highly attractive. A variety of cell sources have been identified as candidates for myocardial repair, including skeletal myoblasts, various bone marrow stem cells, resident cardiac progenitors and embryonic stem cells. However, nearly all studies geared towards myocardial regeneration, both in animal models and in clinical trials, have focused on adult ischemic disease with regional muscle injury. Pediatric patients suffer from more diverse forms of heart disease, including congenital and acquired cardiomyopathies with global muscle dysfunction, as well as disorders of cardiac development, for example, left ventricular hypoplasia, atrial or ventricular septal defects. In this article, a broad range of cell-based therapies are discussed, emphasizing the rapidly evolving science surrounding these strategies and the outstanding questions before application to pediatric patients. It is probable that many of the cell types and delivery strategies capable of repairing adult myocardial diseases will require additional investigations to take advantage of the unique opportunities and challenges of pediatric patients.

Pulmonary Atresia With Intact Ventricular Septum: Initial Management

BACKGROUND

Outcomes for pulmonary atresia with intact ventricular septum are suboptimal, while initial management remains controversial. This study was undertaken to determine the effect of catheter-based therapy on the need for early surgical intervention.

METHODS

A single-institution retrospective chart review was made of all 25 neonates with pulmonary atresia with intact ventricular septum from 1999 to 2005.

RESULTS

Mean age at first intervention was 3.1 +/- 2.2 days, mean weight 3.3 +/- 0.5 kg. Right ventricular hypoplasia varied: 20% normal, 16% mild, 28% moderate, 28% moderately severe or severe, 8% not classified. Median tricuspid valve z-score was -2.3 +/- 2.6. First intervention was catheter-based therapy in 56% (14 of 25), operative in 36% (9 of 25), and no therapy in 2. Technically adequate valvotomy was achieved in 79% (11 of 14). Serious catheter-related complications occurred in 3 of 14 (21%). Only 5 of 14 (36%) with catheter-based therapy weaned from prostaglandins without surgery. Of these, 2 required surgery for cyanosis at 1 and 3 months. Surgery after catheter-based therapy consisted of right ventricular outflow patch in 36% (4 of 11), systemic to pulmonary shunt in 64% (7 of 11). Median time between catheter-based therapy and surgery was 8.5 days (range, 1 to 89). Only 3 of the 23 treated patients avoided operation during infancy. There was 1 early and 1 late death after operation after initial catheter-based therapy, and 1 late death after primary surgery alone during a mean follow-up of 33 months (range, 1.5 to 79).

CONCLUSIONS

Balloon valvotomy alone for pulmonary atresia with intact ventricular septum rarely obviates the need for an additional source of pulmonary blood flow--either shunt or ductal stenting.

Management algorithm in pulmonary atresia with intact ventricular septum

Pulmonary atresia with intact ventricular septum (PAIVS) is a disease with remarkable morphologic variability, affecting not only the pulmonary valve but also the tricuspid valve, the RV cavity and coronary arteries. With advances in interventional techniques and congenital heart surgery, the management of PAIVS continues to evolve. This review is an attempt at providing a practical approach to the management of this disease. The basis of our approach is morphologic classification as derived from echocardiography and angiography. Group A, patients with good sized RV and membranous atresia, the primary procedure at presentation is radiofrequency (RF) valvotomy. Often it is the only procedure required in this group with the most favourable outcome. Patients with severely hypoplastic RV (Group C) are managed along the lines of hearts with single ventricle physiology. The treatment at presentation is patent ductus arteriosus (PDA) stenting with balloon atrial septostomy or conventional modified Blalock Taussig (BT) shunt. Bidirectional Glenn shunt may be done 6-12 months later followed by Fontan completion after a suitable interval. Patients in Group B, the intermediate group, are those with borderline RV size, usually with attenuated trabecular component but well developed infundibulum. The treatment at presentation is RF valvotomy and PDA stenting +/- balloon atrial septostomy. Surgical re-interventions are not uncommonly required viz. bidirectional Glenn shunt when the RV fails to grow adequately (11/2 - ventricle repair) and right ventricular outflow tract (RVOT) reconstruction for subvalvar obstruction or small pulmonary annulus. Catheter based interventions viz. repeat balloon dilatation or device closure of patent foramen ovale (PFO) may also be required in some patients.

Catheterization in neonates with pulmonary atresia with intact ventricular septum

Cardiac catheterization is infrequently required in babies with pulmonary atresia with intact ventricular septum. The main indications are to decide on the best form of treatment, the options being determined by the right ventricular as well as infundibular morphology and the presence of right-ventricle dependent coronary circulation. In most cases, an interventional approach is appropriate. This can consist of radiofrequency or laser perforation of the atretic pulmonary valve, combined with balloon dilation. In some patients, additional stenting of the arterial duct may be needed.

Progression of fetal heart disease and rationale for fetal intracardiac interventions

The outcome of cardiac disease diagnosed before birth is paradoxically worse than that diagnosed postnatally. In part, this is because fetal screening detects cases that are already showing failure of cardiac growth which are usually progressive with secondary damage to the myocardium, lungs and brain. Fetal valvuloplasty has been proposed for cases of critical aortic and pulmonary stenosis or atresia, and atrial septostomy for a restrictive oval foramen associated with aortic stenosis, hypoplastic left heart syndrome and transposition of the great arteries. The rationale for fetal therapy is to restore forward flow and reduce intraventricular pressure, thus improving coronary perfusion and minimizing ischaemic damage. Successful valvuloplasty has reduced systemic venous pressures and reversed fetal hydrops, thus prolonging pregnancy. It has resulted in improved ventricular growth in some cases and spontaneous opening of a closed oval foramen with normalization of pulmonary venous waveforms. These signs suggest better fetal cardiopulmonary development and improved surgical outcomes.

Assessment of right and left ventricular function by tissue Doppler echocardiography in patients after biventricular repair of pulmonary atresia with intact ventricular septum

BACKGROUND

Survival of patients with PAIVS has improved significantly with adoption of a selective management approach based on RV and coronary arterial anatomy. We sought to determine the right (RV) and left ventricular (LV) function of patients with pulmonary atresia and intact ventricular septum (PAIVS) long-term after biventricular repair.

METHODS

The regional ventricular function of 22 patients (11 males) aged 12.8+/-5.6 years with PAIVS after biventricular repair was assessed by tissue Doppler echocardiography (TDE). The results were compared to those of 22 age-matched controls.

RESULTS

When compared with controls, patients had significantly reduced myocardial tissue velocities, systolic and diastolic strain rate, and peak systolic strain in the basal, mid-, and apical segments of the RV free wall, interventricular septum and LV lateral wall (all with p<0.01). Heterogeneity of systolic and diastolic strain rate was observed in the RV free wall and interventricular septum in patients but not in controls.

CONCLUSION

Impairment of RV and LV regional longitudinal myocardial function occurs in patients with PAIVS late after biventricular repair.

Evolution of the management approach for pulmonary atresia with intact ventricular septum

OBJECTIVE

To review the evolution of the management approach for pulmonary atresia with intact ventricular septum (PAIVS) in the past two decades and to assess its impact on patient outcomes.

DESIGN AND PATIENTS

Retrospective review of the management and outcomes of 94 patients (55 male patients) with PAIVS diagnosed between July 1980 and August 2003.

SETTINGS

Tertiary paediatric cardiac centre.

RESULTS

Seven patients died before interventions. Of the remaining 87 patients who underwent intervention at a median age of 9 days (from 1 day to 2 years), 12 had right ventricular outflow tract reconstruction (RVOTR), 42 had closed pulmonary valvotomy (CPV), and 15 had laser assisted valvotomy with balloon valvoplasty. A systemic-pulmonary shunt was inserted in 18 patients, six of whom had subsequent RVOTR (n = 4) or laser assisted valvotomy (n = 2). Since 1990, catheter intervention accounted for 38% (17 of 45) of the right ventricular outflow procedures. The mean (SEM) freedom from reintervention was 93 (7)%, 71 (12)%, and 57 (13)% after RVOTR, 75 (7)%, 40 (8)%, and 14 (6)% after CPV, and 54 (13)%, 24 (12)%, and 16 (10)% after laser assisted valvotomy at one month, six months, and one year, respectively (RVOTR versus CPV, p < 0.001; RVOTR versus laser assisted valvotomy, p = 0.001). Low cardiac output syndrome was significantly less common after catheter intervention than after RVOTR (0% v 44%, p = 0.003) or CPV (0% v 29%, p = 0.01). The overall mean (SEM) survival was 77 (5)% and 70 (5)% at one and five years, respectively, and the overall mortality was 33% (29 of 87). There were no significant differences in survival between the three groups.

CONCLUSIONS

Multiple interventions are often required in the treatment algorithm of PAIVS. The shift towards increased use of the transcatheter approach has reduced the occurrence of postprocedural low cardiac output syndrome.

Risk factors for augmentation of the flow of blood to the lungs in pulmonary atresia with intact ventricular septum after radiofrequency valvotomy

Some patients with pulmonary atresia with an intact ventricular septum, mild to moderate right ventricular hypoplasia, and a patent infundibulum remain duct dependent on the flow of blood through the arterial duct despite adequate relief of the obstruction within the right ventricular outflow tract. The objective of our study was to review the risk factors for stenting of the patent arterial duct, or construction of a Blalock-Taussig shunt, in the patients with pulmonary atresia and an intact ventricular septum who remain duct-dependent following radiofrequency valvotomy and dilation of the imperforate pulmonary valve. We reviewed the data from 53 patients seen between November 1995 and December 2001. Of the 47 patients who survived, 6 required stenting of the patent arterial duct, while 4 needed construction of a modified Blalock-Taussig shunt to augment the flow of blood to the lungs at a mean of 7 plus or minus 5.7 days following the initial intervention. The remaining 37 patients required no additional procedures. We compared the findings in these two groups. The mean diameter of the tricuspid valve in the patients requiring early reintervention was 8.5 plus or minus 3.7 millimetres, giving a Z-score of -1.1 plus or minus 1.47, whilst those in the group without early reintervention had values of 10.7 plus or minus 2.2 millimetres, giving a Z-score of -0.58 plus or minus 1.18 (p equal to 0.003). No statistically significant differences were found in right ventricular morphology, McGoon ratio, or residual obstruction across the right ventricular outflow tract after decompression of the right ventricle. The diameter of the tricuspid valve, therefore, appears to be the only factor predicting the need for augmentation of flow of blood to the lungs. As just over one-fifth of our survivors required such augmentation, we hypothesize that stenting of the patent arterial duct may be performed as an integral part of primary transcatheter therapy in patients with pulmonary atresia and intact ventricular septum who have moderate right ventricular hypoplasia and a small tricuspid valve.

Surgical management of unbalanced atrioventricular canal defect

Approximately 10% of endocardial cushion defects exhibit unbalance at the atrioventricular inlet. When the atrioventricular valve sits more over one ventricle than the other, the contralateral ventricle is typically hypoplastic. Surgical intervention for unbalanced atrioventricular canal has a much higher morbidity and mortality than for the balanced form of the defect. With unbalanced atrioventricular canal to the right, no universal criteria are in place to choose single versus biventricular repair. In many cases, risk factors have been extrapolated from other lesions with left ventricular hypoplasia. Even if biventricular repair is successful, the reoperation rate is high for this lesion. Little data exist in the literature regarding left unbalanced atrioventricular canal. In general, right ventricular hypoplasia is better tolerated than left ventricular hypoplasia, and biventricular repair is usually possible. If cyanosis or high systemic venous pressure results, the one and one half ventricle repair (biventricular repair with bidirectional Glenn anastomosis) is an option. This article reviews the present understanding of unbalanced atrioventricular canal and discusses diagnostic and surgical strategies for this complex lesion.

Pediatric interventional catheterization: reasonable expectations and outcomes

This article considers the role transcatheter therapy plays in the treatment of each major type of congenital heart lesion. The focus is on the clinical ramifications of the interventions rather than their technical aspects.

Interventional cardiac catheterisation in congenital heart disease

As a result of recent technological advances, more types of congenital heart disease are amenable to treatment in the cardiac catheter laboratory than ever before.1 Improved imaging techniques allow for better selection of patients, and the development of a wide range of devices specifically for use in children means that many patients can avoid surgery altogether, while those with complex congenital heart disease may require fewer or less complex surgical procedures.2 This allows for a quicker recovery and a shorter hospital stay, and gives many patients an improved quality of life in the short to medium term. However, the long term outcome for many of the newer forms of intervention is still unknown.