Pulmonary atresia with intact ventricular septum: Strategy based on right ventricular morphology

Pulmonary Atresia with Intact Ventricular Septum: Correlation of Preoperative Computed Tomography-Derived Parameters with Echocardiographic Tricuspid Valve Z-Score and Surgical Outcomes

The role of preoperative cardiac computed tomography (CT) in neonates with pulmonary atresia and intact ventricular septum (PA-IVS) remains unclear. This study was aimed to elaborate the role of preoperative CT-derived anatomical and functional findings in planning treatment strategies in neonates with PA-IVS. The presence of ventriculocoronary arterial connections was evaluated by CT. CT-derived ventricular volumetric parameters were compared and correlated with echocardiographic tricuspid valve (TV) z-score in 12 neonates with PA-IVS. Cardiac CT and echocardiographic findings were compared between definite surgical types (median follow-up, 4 years). Ventriculocoronary arterial connections were identified with CT in 58.3% of cases (7/12) and associated with higher incidence of Fontan procedure (42.9%, 3/7) and high mortality (28.6%, 2/7). The CT-derived and echocardiographic TV z-scores exhibited a high correlation (R = 0.924, p < 0.001). The CT-derived right ventricle (RV) volume and RV-left ventricle volume ratio also displayed high correlations (R = 0.875 and 0.867, respectively; p < 0.001) with echocardiographic TV z-score. More positive echocardiographic TV z-score, high CT-derived RV end-diastolic volume and RV-left ventricle volume ratio, and low CT-derived left ventricular end-diastolic volume were observed in biventricular surgery group (N = 2), compared to Fontan operation (N = 3) and 1.5 ventricular surgery (N = 3) groups, and mortality cases (N = 3). Preoperative CT-derived coronary artery anatomy and ventricular volumetric parameters may supplement treatment planning in neonates with PA-IVS especially when multifactorial decision including echocardiographic TV z-score is in a gray zone.W.

Borderline Ventricles: From Evaluation to Treatment

A heart with a borderline ventricle refers to a situation where there is uncertainty about whether the left or right underdeveloped ventricle can effectively support the systemic or pulmonary circulation with appropriate filling pressures and sufficient physiological reserve. Pediatric cardiologists often deal with congenital heart diseases (CHDs) associated with various degrees of hypoplasia of the left or right ventricles. To date, no specific guidelines exist, and surgical management may be extremely variable in different centers and sometimes even in the same center at different times. Thus, the choice between the single-ventricle or biventricular approach is always controversial. The aim of this review is to better define when "small is too small and large is large enough" in order to help clinicians make the decision that could potentially affect the patient's entire life.

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.

The Use of Chronic Total Occlusion (CTO) Wires for Perforation of Atretic Pulmonary Valve; Two Centers Experience

Pulmonary valve atresia with intact ventricular septum (PA-IVS) can be treated either surgically or transcatheterly for eligible patients. Perforation of pulmonary valves using chronic total occlusion (CTO) guidewires has been reported as an alternative to radiofrequency (RF) perforation. We sought to report our experience with CTO guidewires for perforation of atretic pulmonary valves and subsequent balloon dilatation (with or without patent ductus arteriosus stenting) in patients with PA-IVS from two centers. A retrospective study was carried out on PA-IVS patients who underwent intervention between March 2014 and September 2019, in which CTO guidewire was employed for pulmonary valve perforation. A total of 26 patients were identified. The median age and weight of the patients were 5.2 days (range 1-21 days) and 3.1 kg (range 2.2-3.8 kg), respectively. All patients were situs solitus, except one patient with left atrial isomerism. The right ventricle (RV) morphology was bipartite in 22/26 patients and tripartite in 4/26 patients. Before the procedure, the mean saturation was 76% (range 70-86%) while the patients were under prostaglandin infusion. The pulmonary valve perforation attempt was performed with the Asahi Conquest Pro 9 CTO wire (n = 6) or Asahi Pro 12 CTO wire (n = 18) and/or Asahi Miracle CTO wire (n = 2). The procedure was successful in 20/26 (77%) patients using CTO wires. We analyzed the efficiency of CTO wire based on the subtypes: Conquest Pro 9 in 6/6 (100%) patients, Conquest Pro 12 in 12/18 (67%) patients, and Miracle in 2/2 (100%) patients. Before CTO wire usage in 3 patients, radiofrequency (RF) perforation was unsuccessful. Among these 3 patients, pulmonary valve perforation was successful in 2 patients with CTO wire; hence, in the remaining patient, perforation was also unsuccessful with CTO wire. After CTO wire perforation was unsuccessful in 6 patients, RF perforation was attempted in 3 patients (2 successful attempts and 1 unsuccessful attempts), and one patient as referred to surgery. Desaturation was persistent in 19 cases, which necessitated ductus arteriosus stenting. Early procedural complication was observed in 3/26 (11%) patients. Two of these patients had vascular complications due to the sheath, which was treated with heparin infusion and streptokinase, and the remaining patient had sudden bradycardia and cardiac arrest during the procedure and did not respond to cardiac resuscitation. CTO wires should be keep in mind for atretic pulmonary valve perforation as a first choice or when RF perforation is unsuccessful.

Prediction of biventricular repair by echocardiography in borderline ventricle

Objective:

In recent years, attempting the biventricular pathway or biventricular conversions in patients with borderline ventricle has become a hot topic. However, inappropriate pursuit of biventricular repair in borderline candidates will lead to adverse clinical outcomes. Therefore, it is important to accurately assess the degree of ventricular development before operation and whether it can tolerate biventricular repair. This review evaluated ventricular development using echocardiography for a better prediction of biventricular repair in borderline ventricle.

Data sources:

Articles from January 1, 1990 to April 1, 2019 on biventricular repair in borderline ventricle were accessed from PubMed, using keywords including “borderline ventricle,” “congenital heart disease,” “CHD,” “echocardiography,” and “biventricular repair.”

Study selection:

Original articles and critical reviews relevant to the review's theme were selected.

Results:

Borderline left ventricle (LV): (1) Critical aortic stenosis: the Rhodes score, Congenital Heart Surgeons Society regression equation and another new scoring system was proposed to predict the feasibility of biventricular repair. (2) Aortic arch hypoplasia: the LV size and the diameter of aortic and mitral valve (MV) annulus should be taken into considerations for biventricular repair. (3) Right-dominant unbalanced atrioventricular septal defect (AVSD): atrioventricular valve index (AVVI), left ventricular inflow index (LVII), and right ventricle (RV)/LV inflow angle were the echocardiographic indices for biventricular repair. Borderline RV: (1) pulmonary atresia/intact ventricular septum (PA/IVS): the diameter z-score of tricuspid valve (TV) annulus, ratio of TV to MV diameter, RV inlet length z-score, RV area z-score, RV development index, and RV-TV index, etc. Less objective but more practical description is to classify the RV as tripartite, bipartite, and unipartite. The presence or absence of RV sinusoids, RV dependent coronary circulation, and the degree of tricuspid regurgitation should also be noted. (2) Left-dominant unbalanced AVSD: AVVI, LV, and RV volumes, whether apex forming ventricles were the echocardiographic indices for biventricular repair.

Conclusions:

Although the evaluation of echocardiography cannot guarantee the success of biventricular repair surgery, echocardiography can still provide relatively valuable basis for surgical decision making.

Myocardial strain abnormalities in fetuses with pulmonary atresia and intact ventricular septum

OBJECTIVES

Global and regional myocardial deformation have not been well described in fetuses with pulmonary atresia and intact ventricular septum (PA/IVS). Speckle-tracking echocardiography (STE), an angle-independent technique for assessing global and regional strain, may be a more sensitive way of determining ventricular systolic dysfunction compared with traditional 2D echocardiography. The aim of this study was to assess myocardial deformation in fetuses with PA/IVS compared with control fetuses and to determine if, in fetuses with PA/IVS, strain differs between those with and those without right ventricle-dependent coronary circulation (RVDCC).

METHODS

This was a retrospective analysis of fetuses with PA/IVS examined at two medical centers between June 2005 and October 2017. Left ventricular (LV) and right ventricular (RV) regional and global longitudinal strain (GLS) and strain rate were obtained using STE, and comparisons were made between fetuses with PA/IVS and gestational age (GA)-matched controls. Postnatal outcome was assessed, including the presence of RVDCC.

RESULTS

Fifty-seven fetuses with PA/IVS and 57 controls were analyzed at a mean GA of 26.5 ± 5 weeks. LV-GLS was significantly decreased in fetuses with PA/IVS compared with controls (-17.4 ± 1.7% vs -23.7 ± 2.0%, P < 0.001). LV strain rate was also significantly decreased (-1.01 ± 0.21/s vs -1.42 ± 0.20/s, P < 0.001). Fetuses with PA/IVS had decreased strain in all segments. Similarly, RV strain was significantly decreased in fetuses with PA/IVS (-11.6 ± 3.8% vs -24.6 ± 2.5%, P < 0.0001). Thirty-six patients had postnatal cardiac catheterization performed to define coronary anatomy; 10 fetuses had RVDCC. Fetuses with RVDCC had decreased LV strain compared with those without (-15.8 ± 1.2% vs -17.9 ± 1.7%, P = 0.009). RV strain was also decreased in fetuses with RVDCC vs those without (-7.0 ± 2.9% vs -12.1 ± 3.2%, P = 0.0004).

CONCLUSIONS

Fetuses with PA/IVS have decreased global and regional LV and RV strain compared with controls. The finding of decreased LV strain may be due to altered ventricular mechanics in the context of a hypertensive right ventricle and/or abnormal coronary perfusion. Moreover, fetuses that were found to have RVDCC postnatally had decreased LV and RV strain compared with those that did not. These results encourage further investigation to assess whether fetal ventricular strain could be a prenatal predictor of RVDCC. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Pulmonary Atresia With Intact Ventricular Septum With Borderline Tricuspid Valve: How Small Is Too Small

PA/IVS is a rare, heterogenous congenital heart defect anatomically defined by complete obstruction to the right ventricular outflow tract with varying degrees of hypoplasia of the right ventricle and tricuspid valve. This lesion can have associated coronary artery anomalies and, in some cases, right ventricular-dependent coronary circulation. Due to the wide spectrum of presenting anatomic and clinical features, the treatment options are often dictated by the degree of development of the tricuspid valve and right ventricle. The purpose of this review is to discuss the spectrum of pulmonary atresia with intact ventricular septum morphologies and to evaluate the surgical decision-making process and approaches to surgical repair with respect to the impact of hypoplastic right-sided cardiac features.

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.

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.

Predictors of Mortality in Children with Pulmonary Atresia with Intact Ventricular Septum

Pulmonary atresia with intact ventricular septum (PA/IVS) is a rare cardiac congenital lesion characterized by imperforate pulmonary valve, intact ventricular septum, and atrial level shunt. Although different management strategies to establish a source of non-ductal dependent pulmonary blood flow have been described, studies have not assessed the relationship between the therapeutic approach, patient characteristics, and outcomes. The purpose of this study was to identify predictors of mortality for patients with PA/IVS. Neonates and children with PA/IVS were identified through analysis of the 2012 Kids' Inpatient Database of the Healthcare Cost and Utilization Project. Hospital admissions that included a cardiac catheterization and/or surgical procedure were analyzed to identify demographics, co-morbidities, and outcomes. We identified 508 patients with PA/IVS with hospital admissions that included cardiac catheterization (n = 165), surgical procedures (n = 273), or both (n = 70). The incidence of mortality in this cohort was 6.69% (34/508). Univariable analysis demonstrated that age less than 12 months (p < 0.001), non-elective admission (p < 0.001), AKI (p = 0.001), sepsis (p = 0.002), and the use of ECMO (p < 0.001) were associated with an increased risk of mortality, while no difference was observed for the type of therapeutic approach (p = 0.498). These variables were used in a multivariable logistic regression analysis to develop the predictive model for mortality. Age less than 12 months, non-elective admission, and the use of ECMO in children with PA/IVS were predictors for mortality. Interestingly, the type of therapeutic approach did not influence mortality, which suggests that patient characteristics other than the method chosen to provide pulmonary blood flow determine mortality.

Right ventricular centripetal plication: an aggressive right ventricular exclusion technique

In patients with a functional single ventricle such as neonatal Ebstein's anomaly or pulmonary atresia with intact ventricular septum, the right ventricle can compress the left ventricle and decrease its performance due to the volume or pressure overload of the right ventricle. We have performed right ventricular centripetal plication from the inside to exclude the right ventricle and to minimize the adverse effect on the left ventricle and the results have been satisfactory.

Biventricular repair of pulmonary atresia with intact ventricular septum and severely hypoplastic right ventricle: a case report of a minimum intervention surgical approach

Background

In patients who have pulmonary atresia with an intact ventricular septum and severe right ventricular hypoplasia, biventricular repair is considered to be impossible and multiple interventions are generally required for definitive repair.

Case presentation

An initial palliative procedure was performed in a 1-month-old boy to promote right ventricular development by pulmonary valvectomy without disrupting the annulus, and appropriate oxygenation was achieved with a central funnel shunt. The retained annulus caused functional stenosis and prevented unfavorable right ventricular dilatation due to regurgitation. Thirteen years later, without any other intervention, reconstruction of the right ventricular outflow tract was successfully performed for definitive biventricular repair by using a new expanded polytetrafluoroethylene bulging valved conduit with extended longevity.

Conclusions

The successful outcome in this case suggests that our minimal palliation strategy could be one option for management of these patients.

Biventricular repair versus uni-ventricular repair for pulmonary atresia with intact ventrical septum: A systematic review

The management of pulmonary atresia with intact ventricular septum (PA/IVS) remains controversial. The goal of separating systematic and pulmonary circulation can be achieved by biventricular or uni-ventricular (Fontan or one and a half ventricle repair) strategies. Although outcomes have been improved, these surgical procedures are still associated with high mortality and morbidity. An optimal strategy for definitive repair has yet to be defined. We searched databases for genetically randomized controlled trials (RCTs) comparing biventricular with uni-ventricular repair for patient with PA/IVS. Data extraction and quality assessment were performed following the guidelines of the Cochrane Collaboration. Primary outcome measures were overall survival, and secondary criteria included exercise function, arrhythmia-free survival and treatment-related mortality. A total number of 669 primary citations were screened for relevant studies. Detailed analysis revealed that no RCTs were found to adequately address the research question and no systematic meta-analysis would have been carried out. Nevertheless, several retrospective analyses and case series addressed the question of finding right balance between biventricular and uni-ventricular repair for patient with PA/IVS. In this review, we will discuss the currently available data.

Pulmonary valvuloplasty for pulmonary atresia-restrictive ventricular septal defect

Pulmonary atresia with restrictive ventricular septal defect is a rare congenital cardiac anomaly. A Blalock-Taussig shunt and surgical perforation of the atretic pulmonary valve is often performed as the initial palliation. We present our experience of utilizing both transesophageal and epicardial echocardiography during surgical pulmonary valvuloplasty in a 22-day-old neonate with pulmonary atresia with restrictive ventricular septal defect. The atretic pulmonary valve was perforated using a sheath introduced through the pulmonary artery.

A rare case of biventricular outflow obstruction with intact ventricular septum

We report a case of pulmonary atresia with intact ventricular septum and aortic valve stenosis in a neonate. This combination is extremely rare. Cardiac catheterization was performed at 2 days of age, which confirmed the prenatal echocardiographic diagnosis and identified associated moderate aortic valve stenosis. Soon after the examination, an urgent surgical intervention was required due to uncontrollable circulatory instability. The baby underwent a successful Fontan-type repair achieved by surgical management only.

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.

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.

Late clinical features of patients with pulmonary atresia or critical pulmonary stenosis with intact ventricular septum after biventricular repair

BACKGROUND

We aimed to reveal late clinical features of patients with pulmonary atresia with intact ventricular septum (PA/IVS) or critical pulmonary stenosis (cPS) after biventricular repair (BVR) based on preoperative right ventricular (RV) end-diastolic volume (RVEDV) findings.

METHODS

Since 1985, 23 of 73 patients with PA/IVS (n=22) or cPS (n=1) with a tripartite RV and without major sinusoidal communication underwent BVR with a hybrid approach. The mean age and weight at BVR were 1.4±2.1 years and 6.9±5.9 kg, respectively. Mean follow-up was 10.1±6.4 years (range, 1.1 to 24.6 years).

RESULTS

Overall survival, reintervention-free, and arrhythmia-free rates at 20 years were 90.6%, 75.4%, and 50.4%, respectively. In 19 patients with preoperative RVEDV of 60% to 120% of normal, echocardiography at 10 years after BVR showed well-maintained RV systolic function. However, RV volume was quantitatively dilated in 16 (88.9%) due to moderate or greater tricuspid regurgitation in 8 (44.4%), pulmonary regurgitation in 12 (66.7%), or both, which caused arrhythmia in 3 patients more than 10 years after BVR. Two patients with preoperative RVEDV of greater than 120% of normal required tricuspid valve replacement after BVR, after which refractory atrial tachyarrhythmia developed in both patients. Furthermore, 2 patients with preoperative RVEDV of less than 60% of normal showed a cardiac index value within 2.5 L/min/m2 at 1 year after BVR, which did not improve.

CONCLUSIONS

Patients with PA/IVS or cPS and adequately sized RV showed good late clinical features after BVR. However, long-term follow-up examinations are necessary for RV dilatation and late-onset arrhythmia.

Mechanical loading of stem cells for improvement of transplantation outcome in a model of acute myocardial infarction: the role of loading history

Stem cell therapy for tissue repair is a rapidly evolving field and the factors that dictate the physiological responsiveness of stem cells remain under intense investigation. In this study we hypothesized that the mechanical loading history of muscle-derived stem cells (MDSCs) would significantly impact MDSC survival, host tissue angiogenesis, and myocardial function after MDSC transplantation into acutely infarcted myocardium. Mice with acute myocardial infarction by permanent left coronary artery ligation were injected with either nonstimulated (NS) or mechanically stimulated (MS) MDSCs. Mechanical stimulation consisted of stretching the cells with equibiaxial stretch with a magnitude of 10% and frequency of 0.5 Hz. MS cell-transplanted hearts showed improved cardiac contractility, increased numbers of host CD31+ cells, and decreased fibrosis, in the peri-infarct region, compared to the hearts treated with NS MDSCs. MS MDSCs displayed higher vascular endothelial growth factor expression than NS cells in vitro. These findings highlight an important role for cyclic mechanical loading preconditioning of donor MDSCs in optimizing MDSC transplantation for myocardial repair.

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.

[Pulmonary stenosis and atresia with intact ventricular septum]

Pulmonary atresia and critical pulmonary stenosis with intact ventricular septum includes a wide spectrum of cardiopathies with great morphological heterogeneity. The pulmonary valve may be completely atretic or may contain a puncture hole if stenosis is present. The obstruction may be membranous and/or muscular. All components of the right ventricle can be affected, even the coronary circulation with ventriculocoronary connections and stenosis or atresia of the pulmonary arteries. Prenatal diagnosis is made when the right ventricle is hypoplastic and hypertrophic. The pulmonary valve is thickened and the pulmonary artery is perfused retrogradely through the ductus arteriosus. Right ventriculocoronary connections may sometimes be seen with fetal echocardiography. Postnatal survival depends on the patency of the ductus arteriosus, requiring prostaglandin E1 infusion. When hypoplastic right ventricle and/or ventricle-dependent coronary circulation exists, biventricular circulation is not possible. In these cases, surgical treatment is palliative. In cases with well-developed right ventricle, transcatheter therapy is usually provided with perforation and balloon dilation of the pulmonary valve. In cases of muscular obstruction of the right ventricle outflow tract, surgery may be considered as first-line therapy. In case of prenatal diagnosis, the medical termination of pregnancy is possible when severe right ventricular hypoplasia exists, precluding biventricular circulation. Postnatally, the prognosis of the patients is highly variable, mainly related to the size of the right cavities and the presence of coronary anomalies.

Right ventricular stiffness constant as a predictor of postoperative hemodynamics in patients with hypoplastic right ventricle: a theoretical analysis

One and a half ventricle repair (1.5VR) is a surgical option for hypoplastic right ventricle (RV). The benefits of this procedure compared to biventricular repair (2VR) or Fontan operation remain unsettled. To compare postoperative hemodynamics, we performed a theoretical analysis using a computational model based on lumped-parameter state-variable equations. We varied the RV stiffness constant (B (RV)) to simulate the various RV hypoplasia, and estimated hemodynamics for a given B (RV). With B (RV) < 150% of normal, cardiac output was the largest in 2VR. With B (RV) > 150%, cardiac output became larger in 1.5VR than in 2VR. With B (RV) > 250%, RV end-diastolic volume was almost the same between 1.5VR and 2VR, and a rapid increase in atrial pressure precluded the use of 1.5VR. These results indicate that the beneficial effect of 1.5VR depends on the RV stiffness constant. Determination of management strategy should not only be based on the morphologic parameters but also on the physiological properties of RV.

Fetal tricuspid valve size and growth as predictors of outcome in pulmonary atresia with intact ventricular septum

OBJECTIVE

Pulmonary atresia with intact ventricular septum is a complex congenital cardiovascular anomaly that frequently requires single ventricle palliation. Fetal diagnosis of pulmonary atresia with intact ventricular septum is common, but the natural history of pulmonary atresia with intact ventricular septum diagnosed in midgestation, predictors of neonatal anatomy, and predictors of biventricular repair have not been determined. The objective of this study was to determine whether the size and rate of growth of the fetal tricuspid valve predict neonatal anatomy and biventricular repair.

DESIGN AND RESULTS

Twenty-three fetuses diagnosed with pulmonary atresia with intact ventricular septum between 1990 and 2004 were studied. Of 13 fetuses with a midgestation fetal tricuspid valve z score < or = -3, 1 achieved biventricular repair, compared with 5 of 5 with a tricuspid valve z score > -3. Of 13 fetuses with a midgestation fetal tricuspid valve z score < or = -3, 8 were diagnosed postnatally with a right ventricular dependent coronary circulation, compared with none with a tricuspid valve z score > -3. Midgestation and late gestation fetal tricuspid valve z scores correlated with neonatal tricuspid valve z score. The average rate of tricuspid valve growth between mid- and late fetal echocardiograms was significantly lower in patients who did not achieve biventricular repair than in those who did (0.012 +/- 0.008 cm per week vs 0.028 +/- 0.014 cm per week).

CONCLUSIONS

Fetal tricuspid valve z score and rate of growth predict postnatal outcome in pulmonary atresia with intact ventricular septum. These findings may have important implications for prenatal counseling and selection of patients for fetal pulmonary valve dilation.

Changes in tissue Doppler characteristics in a patient with pulmonary atresia and intact ventricular septum

Tissue Doppler measurements of the right and left lateral ventricular walls were made before and after perforation of the pulmonary valve using radiofrequency energy in a patient with pulmonary atresia and intact ventricular septum. The ratio of peak tissue velocity during rapid ventricular filling to atrial contraction increased for both atrioventricular valves after perforation of the pulmonary valve, and the patient was able to be weaned off prostaglandins without further intervention. Such measurements made using tissue Doppler may aid in the management of patients with pulmonary atresia and intact ventricular septum by predicting improvements in right ventricular relaxation.

Pulmonary atresia, intact ventricular septum, right ventricle-dependent coronary artery circulation, and systemic collateral arteries supplying the left coronary artery

We present a 14-day-old with pulmonary artery atresia with intact ventricular septum, right ventricle-dependent coronary circulation, a single aortic root coronary ostia (left), congenital collateral arterial supply to the left coronary artery from the left internal mammary artery, and bilateral paravertebral arteries, with obstructive coronary artery lesions.

Pulmonary atresia with intact ventricular septum: Predictors of early and medium-term outcome in a population-based study

OBJECTIVES

Pulmonary atresia with intact ventricular septum is a form of congenital heart disease usually associated with right-heart hypoplasia, with considerable morphologic heterogeneity and often poor outlook. Ascertainment of risk factors for poor outcome is an important step if an improvement in outcome is to be achieved.

METHODS

The UK and Ireland Collaborative study of Pulmonary Atresia with Intact Ventricular Septum is an ongoing population-based study of all patients born with this disease from 1991 through 1995. All available clinical, morphologic, and investigative variables were directly reviewed, and risk factor analysis was performed for poor outcome.

RESULTS

One hundred eighty-three patients presented with pulmonary atresia with intact ventricular septum. Fifteen underwent no procedure, and all died. Of the remainder, 67 underwent a right ventricular outflow tract procedure (catheter or surgical), 18 underwent an outflow tract procedure with shunt, and 81 underwent a systemic-to-pulmonary shunt alone. One- and 5-year survival was 70.8% and 63.8%, respectively. Results from Cox proportional hazards model analysis showed that low birth weight (P = .024), unipartite right ventricular morphology (P = .001), and the presence of a dilated right ventricle (P < .001) were independent risk factors for death. The presence of coronary artery fistulae, right ventricular dependence, or the tricuspid valvar z score did not prove to be risk factors for death. After up to 9 years of follow-up, 29% have achieved a biventricular repair, 3% a so-called one-and-a-half ventricular repair, and 10.5% a univentricular repair, with 16.5% still having a mixed circulation (41% died).

CONCLUSIONS

This population-based study has shown which features at presentation place an infant in a high-risk group. This is important information for counseling in fetal life and for surgical strategy after birth.

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.

Left ventricular performance of pulmonary atresia with intact ventricular septum after right heart bypass surgery

OBJECTIVE

The left ventricular performance in patients with pulmonary atresia with intact ventricular septum who were Fontan candidates before and after the bidirectional Glenn procedure and a staged total cavopulmonary connection was compared with that in patients with tricuspid atresia.

METHODS

Contractility (end-systolic elastance), afterload (effective arterial elastance), and ventricular efficiency (ventriculoarterial coupling, arterial elastance/end-systolic elastance ratio), and the ratio of stroke work and pressure-volume area were approximated on the basis of cardiac catheterization data before the bidirectional Glenn procedure, before and after staged total cavopulmonary connection, and approximately 1 year after the completion of total cavopulmonary connection in 20 patients with pulmonary atresia with intact ventricular septum and 21 patients with tricuspid atresia.

RESULTS

The end-systolic elastance of the pulmonary atresia with intact ventricular septum group was significantly inferior to that of the tricuspid atresia group after bidirectional Glenn procedure and total cavopulmonary connection (1 year after total cavopulmonary connection 1.85 +/- 0.51 mm Hg . m 2 . mL -1 vs 2.84 +/- 0.96 mm Hg . m 2 . mL -1 , P < .01). The arterial elastance was not different between groups throughout the assessment period and tended to increase in a stepwise fashion after bidirectional Glenn procedure and total cavopulmonary connection. The arterial elastance/end-systolic elastance ratio and ratio of stroke work and pressure-volume area of the pulmonary atresia with intact ventricular septum group tended to worsen, whereas those of the tricuspid atresia group tended to improve. The difference reached statistical significance 1 year after total cavopulmonary connection (1.15 +/- 0.35 vs 0.82 +/- 0.23 and 64.2% +/- 6.7% vs 71.3% +/- 5.7%, respectively, P < .05 and P < .05, respectively).

CONCLUSION

The contractility and ventricular efficiency of patients with pulmonary atresia with intact ventricular septum are inferior to those of patients with tricuspid atresia after bidirectional Glenn procedure and total cavopulmonary connection. A high-pressure residual right ventricle may impair the left ventricular performance of patients with pulmonary atresia with intact ventricular septum after bidirectional Glenn procedure and total cavopulmonary connection.