Right ventricular volume determinations in 18 patients with pulmonary atresia and intact ventricular septum. Analysis of factors influencing right ventricular growth

Staged Percutaneous Management of Pulmonary Atresia and Intact Interventricular Septum: Stretching the Limits

Aims

Pulmonary atresia with intact ventricular septum (PA/IVS) can be treated by catheter-based interventions and complemented by various surgical procedures. We aim to determine a long-term treatment strategy to enable patients to be surgery free, depending solely on percutaneous interventions.

Methods and Results

We selected five patients from among a cohort of patients with PA/IVS treated at birth with radiofrequency perforation and dilatation of the pulmonary valve. Patients had reached a pulmonary valve annulus of 20 mm or larger on their biannual echocardiographic follow-up, with right ventricular dilatation. The findings, together with the right ventricular outflow tract and pulmonary arterial tree, were confirmed by multislice computerised tomography. Based on the angiographic size of the pulmonary valve annulus, all patients were successfully implanted with either Melody® or Edwards® pulmonary valves percutaneously, regardless of their small weights and ages. No complications were encountered.

Conclusion

We managed to stretch the age and weight limitations for performing percutaneous pulmonary valve implantation (PPVI): interventions were attempted whenever a pulmonary annulus size of >20 mm was reached, which was rationalised by the prevention of progressive right ventricular outflow tract dilatation and accommodating valves between 24 and 26 mm, which is enough to sustain a normal pulmonary flow in adulthood.

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.

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.

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.

Perforation of the atretic pulmonary valve. Long-term follow-up

OBJECTIVES

We evaluated the long-term results of perforation of the pulmonary valve in patients with pulmonary atresia with an intact ventricular septum (PA-IVS).

BACKGROUND

Interventional perforation of the pulmonary valve is considered the elective first stage treatment for PA-IVS, particularly in patients with a tripartite right ventricle (RV) and normal coronary circulation. However, the long-term results of this procedure are lacking.

METHODS

Between January 1991 and December 2001, 39 newborns with a favorable form of PA-IVS underwent attempted perforation of the pulmonary valve. We evaluated the early and long-term outcomes.

RESULTS

Median tricuspid and pulmonary z values were -1.2 and -2.4, respectively. Perforation was successful in 33 patients. Among them, 17 needed neonatal surgery, 13 did not need any surgery, and 3 had elective surgery after the first month of life. There were two procedure-related deaths, seven nonfatal procedural complications, and four postsurgical deaths. Compared with patients needing neonatal surgery, those having no or elective surgery had a higher incidence of a tripartite RV and a higher median tricuspid z value (92% vs. 53%, p = 0.04 and -1.7 vs. -0.5, p = 0.03). At a median follow-up of 5.5 years (range 0.5 to 11.5), survival was 85% and freedom from surgery was 35%. Five patients, four of whom had neonatal surgery, underwent a partial cavo-pulmonary connection.

CONCLUSIONS

Our results show that this technique, although burdened by non-negligible mortality and morbidity, is effective in selected patients with a normal-sized RV. Preselection of patients allows interventional or surgical biventricular correction in the majority of cases.

The outcome of children born with pulmonary atresia and intact ventricular septum in Sweden from 1980 to 1999

OBJECTIVE

To study the outcome of all children born with pulmonary atresia and intact ventricular septum in Sweden between 1980 and 1999.

DESIGN

Retrospective study of medical records with review of the initial, preoperative angiocardiographic and echocardiographic examinations.

RESULTS

A total of 84 children were born with pulmonary atresia and intact ventricular septum, giving an incidence of 4.2 per 100,000 live births. In all, 77 were operated on with a 1-year survival rate of 75%. Thirty-six children had ventriculocoronary communications, with a 1-year survival rate of 50%. At the end of the study period, 52 children were alive, 32 with biventricular repair, and 19 with univentricular repair. Follow-up time was 14 days-20 years (median, 6 years). Statistical analysis of incremental risk factors for death showed statistical significance for low birth weight, male sex, muscular pulmonary atresia, and having a systemic-to-pulmonary shunt as the sole initial intervention.

CONCLUSION

Complete national data of all patients born with pulmonary atresia and intact ventricular septum during 1980-1999 in Sweden revealed a total mortality in accordance with previous reports for results for surgery. Further improvements demand a thorough preoperative investigation of the cardiac anatomy, particularly of the ventriculocoronary communications, to enable right ventricular decompression whenever possible.

Staged biventricular repair of pulmonary atresia or stenosis with intact ventricular septum

BACKGROUND

Since 1991 we have performed a multistage palliative approach to biventricular repair of pulmonary atresia or critical pulmonary stenosis with intact ventricular septum in infants with a detectable right ventricular infundibulum.

METHODS

A total of 25 patients (19 pulmonary atresia and 6 critical pulmonary stenosis) underwent initial palliation consisting of a transarterial pulmonary valvotomy and a polytetrafluoroethylene shunt between the left subclavian artery and pulmonary trunk. Among the 23 survivors, 15 underwent balloon valvotomy. Six of these patients later required additional palliative surgery that consisted of repeat pulmonary valvotomy, adjustment of an atrial communication, and resection of the hypertrophied muscles in the right ventricle.

RESULTS

Of the 25 patients, 23 (92%) survived. In all, 20 patients underwent definitive operations: 18 (90%) biventricular repair (12 pulmonary atresia, and 6 critical pulmonary stenosis), one bidirectional Glenn, and one Fontan procedure. The actuarial probability of achieving a biventricular repair at 36 months of age was 69%. In 18 patients right ventricular end-diastolic volume significantly increased but tricuspid valve diameter did not change.

CONCLUSIONS

The multistage palliation procedure to promote right ventricular growth makes a definitive biventricular repair of pulmonary atresia or critical pulmonary stenosis with intact ventricular septum possible in the majority of infants with a patent infundibulum.

Long-term outcome for right heart function after biventricular repair of pulmonary atresia and intact ventricular septum

OBJECTIVES

The right heart function of the patients with pulmonary atresia and intact ventricular septum was assessed periodically during the process of staged biventricular repair, and the implications for its long-term outcome were analyzed.

SUBJECTS AND METHODS

During the period from 1971 to 1990, 21 neonates or infants with pulmonary atresia and intact ventricular septum had undergone initial palliative surgery. There were seven early postoperative deaths and one late death. Of the 13 survivors, 10 patients underwent subsequent biventricular repair and form the basis of this study. Their clinical records of roentgenography, electrocardiography, and catheterization studies at each staged period were reviewed retrospectively.

RESULTS

Arrhythmia occurred late in 2 patients, one of whom died by arrhythmia at 11 years after definitive surgical repair. Therefore the actuarial survival rate was 85.7% at 14 years. The catheterization study after the definitive biventricular repair revealed a significant fall in the right heart pressure (p = 0.0005) and significant improvement in the right ventricular ejection fraction (p = 0.0004). In angiocardiography, dilatation of the right atrium was noted in all patients and was more marked in those who developed arrhythmia in conjunction with rapid growth of the right ventricle. Moreover, the serial repeated electrocardiography disclosed progressive and significant prolongation of both PQ interval (p = 0.003) and QRS duration (p = 0.021).

CONCLUSIONS

Although biventricular repair for pulmonary atresia and intact ventricular septum proved to attain a satisfactory long-term result, it failed to resolve right heart dysfunction. Postoperative arrhythmia was prone to precipitate progressive dilatation of the right atrium.

Pulmonary atresia with intact ventricular septum percutaneous radiofrequency-assisted valvotomy and balloon dilation versus surgical valvotomy and Blalock Taussig shunt

OBJECTIVE

We compared the result of radiofrequency (RF)-assisted valvotomy and balloon dilation with closed surgical valvotomy and Blalock Taussig (BT) shunt as primary treatment in selected patients with pulmonary atresia and intact ventricular septum (PA-IVS).

BACKGROUND

Patients with PA-IVS who have mild to moderate hypoplasia of the right ventricle (RV) and patent infundibulum have the greatest potential for complete biventricular circulation. The use of RF or laser wires to perforate the atretic valve followed by balloon dilation provides an alternative to surgery.

METHODS

Between May 1990 and March 1998, 33 selected patients underwent either percutaneous RF valvotomy and balloon dilation (group 1, n = 21; two crossed over to group 2) or surgical valvotomy with concomitant BT shunt (group 2, n = 14). Second RV decompression by balloon dilation or right ventricular outflow tract (RVOT) reconstruction were performed if necessary. Patients who remained cyanosed were subjected to transcatheter trial closure of the interatrial communication. Partial biventricular repair was offered to those with inadequate growth of the RV.

RESULTS

The primary procedure was successful in 19 patients in group 1. There was one in-hospital death and two late deaths. Of the remaining 16 survivors, 12 achieved complete biventricular circulation, 7 of whom required no further interventions. Two patients required repeat balloon dilation, 1 RVOT reconstruction and 2 transcatheter closure of interatrial communication. Two patients underwent partial biventricular repair. In group 2, there were 3 in-hospital deaths after the primary procedure and 1 patient died four months later. All survivors (n = 10) required a second RV decompression, 8 by balloon dilation and 2 by RVOT reconstruction, after which, two patients died. Of the final 8 survivors, 7 achieved complete biventricular circulation, 5 after coil occlusion of the BT shunt and 2 after closure of interatrial communication.

CONCLUSIONS

Radiofrequency valvotomy and balloon dilation is more efficacious and safe compared with closed pulmonary valvotomy and BT shunt in selected patients with PA-IVS.

Evaluation and management of pulmonary atresia with intact ventricular septum

Pulmonary atresia with intact ventricular septum (PA/IVS) is a spectrum of diseases with varying severity of right ventricle hypoplasia and potential for biventricular, univentricular, or hybrid repairs. Pessimistic outcome measures for PA/IVS may give way to optimism with the refinement of early diagnosis and early intervention to encourage right ventricle flow and optimize growth. To this end, PA/IVS has become a focus of innovative interventions (e.g., fetal surgery) and new catheter-based and surgical techniques.

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

OBJECTIVES

Since 1990, transcatheter pulmonary valvotomy has become an alternative to surgical valvotomy in the management of neonates and infants with pulmonary atresia and intact ventricular septum. We sought to determine whether right ventricular growth after transcatheter pulmonary valvotomy is commensurate with body growth.

METHODS

Laser or radiofrequency-assisted balloon valvotomy was attempted in 12 neonates and infants with pulmonary atresia and intact ventricular septum. Tricuspid and mitral valve dimensions were measured retrospectively on the cross-sectional echocardiograms performed before the procedure and during follow-up. Z-values were used to standardize tricuspid valve dimensions with body size.

RESULTS

The atretic pulmonary valve was successfully perforated and dilated in nine of 12 patients. Five of these nine patients required additional transcatheter or surgical procedures to augment the pulmonary blood flow. Of six survivors, five are regularly followed up with a median follow-up of 60 months (range 37 to 68 months). All five have two-ventricle circulation, two of the five patients requiring surgical enlargement of the right ventricular outflow tract with or without closure of the atrial septal defect. Echocardiographic tricuspid valve dimensions and Z-values before transcatheter valvotomy tended to be smaller in the patients who died than in the survivors. In the survivors, the absolute tricuspid valve dimensions increased after valvotomy but the Z-values tended to decrease or stayed constant.

CONCLUSIONS

Transcatheter valvotomy is a good alternative to surgical valvotomy in patients with pulmonary atresia and intact ventricular septum. Two-ventricle circulation can be achieved despite subnormal right ventricular growth.

Bidirectional cavopulmonary anastomosis with intracardiac repair

BACKGROUND

Patients with hypoplasia of the right ventricle and tricuspid valve have historically undergone a total cavopulmonary connection or a two-ventricle repair with atrial fenestration.

METHODS

We reviewed our experience with 9 patients with hypoplasia of the right ventricle and tricuspid valve who underwent a bidirectional cavopulmonary anastomosis with intracardiac repair. Patient diagnoses included pulmonary atresia with intact ventricular septum (n = 3); hypoplastic right ventricle and tricuspid valve with atrial septal defect, ventricular septal defect, and right ventricular outflow tract obstruction (n = 3); unbalanced atrioventricular canal defect (n = 1); inlet ventricular septal defect with coarctation (n = 1); and tricuspid stenosis with atrial septal defect (n = 1).

RESULTS

The median age at operation was 36 months. There was hypoplasia of the right ventricle and tricuspid valve in all patients. The tricuspid valve measured 56.5% of normal (range, 43.6% to 70.4%) by echocardiography, and the median ratio of the tricuspid valve to the mitral valve was 0.67 (range, 0.54 to 0.82). At operation, the median tricuspid valve annulus diameter was 65.6% of published autopsy normals (range, 57.8% to 78.5%) with a median Z value of -3.8 (range, -6.6 to -2.1). All patients survived operation. At a median follow-up of 16 months, 5 patients are asymptomatic, and 2 have occasional early-morning periorbital edema. Two patients are on a regimen of diuretics, 1 of whom is also taking an unloading agent. The patient with unbalanced atrioventricular canal died suddenly at home 6 months postoperatively.

CONCLUSIONS

Bidirectional cavopulmonary anastomosis with intracardiac repair may avoid the long-term complications associated with the Fontan modifications and eliminates the need of atrial fenestration in most instances. This operation should be considered for select patients with hypoplasia of the right ventricle and tricuspid valve.

Pulmonary atresia with intact ventricular septum: results of the Fontan procedure

BACKGROUND

Children with pulmonary atresia and an intact ventricular septum show a heterogeneous spectrum of cardiac anomalies. A biventricular repair is attainable in some; a Fontan procedure or a one-and-a-half ventricle is the only possible repair for others. Children with right ventricle-to-coronary artery connections, with or without right ventricle-dependent coronary artery blood flow, are a high-risk group.

METHODS

Between May 1980 and December 1994, 22 children underwent a Fontan operation for the treatment of pulmonary atresia with an intact ventricular septum at The Hospital for Sick Children, Toronto. The mean age was 5.8 years (median, 4.9 years). All children had had at least one pre-Fontan palliative procedure; 19 had two, and 7 of these had three or more. Right ventricle-to-coronary artery connections were present in 15 children, including 5 with right ventricle-dependent coronary artery blood flow. Thromboexclusion of the right ventricle was done in 10 children, with 7 undergoing it before and 3 at the time of the Fontan procedure.

RESULTS

There were three early deaths (13.6%) and one late death. The actuarial survival at 10 years after the Fontan operation was 80%. Early postoperative complications occurred in 4 children. Follow-up was completed in all children at a mean of 4 years (range, 1 to 12.5 years) after the Fontan operation. Atrial arrhythmia occurred in 3 children, and permanent pacemakers were required in 4.

CONCLUSIONS

Results of the Fontan operation for the treatment of pulmonary atresia with an intact ventricular septum are satisfactory. Thromboexclusion of the right ventricle is indicated in the presence of right ventricle-to-coronary artery connections without right ventricle-dependent coronary artery blood flow. The right ventricle should not be decompressed or thromboexcluded in children with right ventricle-dependent coronary artery blood flow, and at the Fontan operation, saturated blood must enter the right ventricle.

Quantitation of the effective right ventricular output in patients with pulmonary atresia and intact ventricular septum after placement of a right ventricular outflow patch and an aorticopulmonary shunt

A mathematical derivation is presented of an equation that allows quantitation, in the cardiac catheterization laboratory, of the effective output of the right ventricle (QRV) in patients with pulmonary atresia and intact ventricular septum (PA/IVS) after palliation with a right ventricular outflow patch and an aorticopulmonary shunt. This derivation is based on the Fick principle and accounts for that portion of the right-to-left atrial shunt that flows through the aorticopulmonary shunt to the lungs and thus contributes to the effective pulmonary blood flow (Qep). This equation relates QRV to pulmonary blood flow (Qp), systemic cardiac output (Qs), and Qep by QRV = Qp + Qs - (Qp)(Qs)/Qep. By providing an assessment of right ventricular function, this equation may be helpful in determining the suitability of the right ventricle to support biventricular repair.

Influence of right heart size on outcome in pulmonary atresia with intact ventricular septum

BACKGROUND

Neonates with pulmonary atresia and intact ventricular septum (PA-IVS) are frequently born with hypoplastic right heart structures that must grow after right ventricular decompression (RVD) procedures for a complete two-ventricle physiology to be achieved. Previous authors have asserted that neonatal right heart size or morphology will predict right heart growth potential. Since 1983, our bias has favored early RVD regardless of initial right heart size. In 1986, we recognized a subset of patients with coronary artery abnormalities associated with poor outcome after RVD and have defined these patients as having a right ventricular-dependent coronary circulation (RVDCC).

METHODS AND RESULTS

To assess the influence of right heart size on outcome independent of the presence of RVDCC, we measured echocardiographic right ventricular (RV) dimensions in 37 neonates with adequate studies presenting between 1983 and 1990. Coronary artery anatomy was adequately assessed by angiography in 36. RV volume and tricuspid valve (TV) diameter were significantly smaller in patients with RVDCC than in those without. However, there was no statistically significant association between RV volume or TV diameter and survival among patients with or without RVDCC: Among 29 patients without RVDCC, 23 of 24 (95.8%) who achieved RVD are alive compared with 1 of 5 (20%) who did not achieve RVD (P = .001). Twenty-one of the 23 survivors have a complete two-ventricle physiology with low right atrial pressure. Among 7 patients with RVDCC, 2 patients who underwent RVD died early of left ventricular failure, whereas 4 of 5 who did not undergo RVD have survived single ventricular palliation.

CONCLUSIONS

Small right heart size is associated with RVDCC but is not associated with survival in PA-IVS. Patients without RVDCC have improved survival after RVD regardless of neonatal right heart size.

Pulmonary atresia with intact ventricular septum: surgical management based on right ventricular infundibulum

The optimal management of infants with pulmonary atresia with intact ventricular septum (PA.IVS) remains a controversy. Attempts have been made to base the surgical approach on various geometrical or morphological characteristics of the right ventricle (RV). However, the overall results remain poor when compared to other complex congenital heart defects. Forty-eight neonates with PA.IVS were admitted to our unit between 1980 and 1992. The management plan has evolved to be based entirely on the echocardiographic assessment of the state of development of the infundibulum of the RV. In neonates with a well-formed infundibulum (n = 31), the initial palliation consisted mainly of pulmonary valvotomy (without cardiopulmonary bypass) and PTFE shunt from the left subclavian artery to the main pulmonary artery. There was one death from initial palliation in this subgroup. If necessary, the RV cavity was later enlarged by excision of the hypertrophic muscle of both the trabecular and infundibular portions, before finally attempting biventricular repair. The actuarial probability of achieving a biventricular repair at 40 months of age was 60% (95% CL = 39.5% to 71.3%). Thirteen patients have undergone biventricular repairs with one late death over a total follow-up of 1,720 patient months. In one patient, the RV failed to grow satisfactorily, necessitating a Fontan procedure. Seventeen patients without a well-formed infundibulum were approached with a Fontan procedure in mind. The initial palliation in these patients consisted of a modified Blalock-Taussig shunt only. Ten have undergone a Fontan procedure so far and five are awaiting such repairs. In this group there were four operative deaths: two after initial palliation, and two after Fontan procedures. In patients with a well-developed infundibulum, the actuarial survival probability was 93% (95% CL = 74% to 98%) at 8 months with no further late deaths over 120 months follow-up, whereas in patients without a well-formed infundibulum it was 75% at 40 months (95% CL = 46% to 89%). The overall survival probability at 104 months was 77% (95% CL = 51% to 90%).

Diagnosis and management of right ventricle-dependent coronary circulation in pulmonary atresia with intact ventricular septum

BACKGROUND

Coronary artery anomalies including 1) right ventricle (RV)-to-coronary artery fistulas, 2) coronary artery stenoses, and 3) coronary occlusions occur in patients with pulmonary atresia with intact ventricular septum (PA-IVS). In some, a large part of the coronary blood supply may depend on the RV. This RV-dependent coronary circulation may determine survival after right ventricular decompression (RVD): RVD may cause RV "steal" in the presence of fistulas alone and ischemia, coronary isolation, or myocardial infarction in the presence of coronary stenoses.

METHODS AND RESULTS

Eighty-two patients with PA-IVS who presented between January 1979 and January 1990 were reviewed; 26 (32%) had RV-to-coronary artery fistulas. Of these 26, 23 had adequate preoperative coronary angiograms for analysis. RVD was achieved in 16. Seven of 16 had fistulas only; each survived RVD. Six of 16 had stenosis of a single coronary artery [left anterior descending coronary artery (LAD), four; right coronary artery (RCA), two]; four of six survived RVD. Three of 16 had stenoses and/or occlusion of both the RCA and LAD; all three died shortly after RVD of acute left ventricular dysfunction.

CONCLUSIONS

1) Potential RV steal alone does not preclude successful RVD. 2) Fistulas with stenoses to a single coronary artery may not preclude successful RVD. 3) RVD appears to be contraindicated in the presence of stenoses and/or occlusion involving both the right and left coronary systems. Nonsurvival after RVD seems to depend on the amount of the left ventricular myocardium at risk, i.e., that which is distal to coronary artery stenoses, especially when involvement of both coronary arteries limits effective collateralization. Precise definition of coronary arterial anatomy is mandatory in neonates with PA-IVS.

Changes of right ventricular size and function in neonates after valvotomy for pulmonary atresia or critical pulmonary stenosis and intact ventricular septum

Right ventricular end-diastolic and stroke volumes were calculated from orthogonal subcostal echocardiographic images in 24 neonates (mean weight +/- SD 3.4 +/- 0.4 kg) with pulmonary atresia (n = 18) or critical pulmonary stenosis (n = 6) and intact ventricular septum before and at an average of 5 days and then 19 days after pulmonary valvotomy. The preoperative echocardiographic volume determinations were compared with the respective angiographic determinations. In addition, the endocardial area outlines of the left and right ventricles were obtained by planimetry from an end-diastolic frame taken in the apical four-chamber view. End-diastolic and stroke volumes calculated by the echocardiographic method (y) correlated closely with those calculated by the angiographic method (x); the regression equations were y = 1.02 x -0.13 (r = 0.95, SEE +/- 0.45 ml) and y = 1.16 x -0.15 (r = 0.89, SEE +/- 0.38 ml), respectively. All except one infant had right ventricular hypoplasia before valvotomy with an end-diastolic volume of 16.6 +/- 6.4 ml/m2 (44.5 +/- 17.3% of normal). Right to left ventricular area ratio was 0.56 +/- 0.09 (normal 0.95). Five days after valvotomy, right ventricular end-diastolic volume decreased to 10.6 +/- 4.6 ml/m2 (p less than 0.05) and stroke volume decreased from 8.3 +/- 3.5 to 5.5 +/- 2.8 ml/m2 (p less than 0.05). Nineteen days after valvotomy, right ventricular end-diastolic volume and right to left ventricular area ratio had increased to their respective preoperative values; right ventricular stroke volume had increased further to 10.4 +/- 3.9 ml/m2 (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Cross-sectional echocardiographic measurements of right ventricular size and growth in patients with pulmonary atresia and intact ventricular septum

Fifteen patients with pulmonary atresia or critical pulmonary stenosis and intact ventricular septum were studied. All were operated on in the neonatal period, with valvotomy or a systemic to pulmonary arterial shunt, or both. In 12 patients, right ventricular to pulmonary arterial communication was established in the neonatal period. In three patients, only systemic to pulmonary arterial shunts were constructed. Six patients died. The median follow-up period for the surviving patients was 64 months (range, 12-87 months). Right and left atrial and ventricular dimensions and areas, the tricuspid annular diameter, and the cross-sectional area of the aortic root were measured in cross-sectional echocardiograms from the neonatal period, at the age of 1 year, and at the latest clinical follow-up. A classification of right ventricular morphology was made, based on identification of the inlet, the trabecular, and the outlet parts. Most of the patients had hypoplastic right ventricles at birth but at the latest follow-up, seven of nine surviving patients had right ventricles in the normal range. Right ventricular growth was better in patients who were given a right ventricular to pulmonary arterial communication in the neonatal period and those with complete right ventricular anatomy. The patients who died had severely hypoplastic right ventricles and small tricuspid valves.

Abnormalities of the coronary circulation in pulmonary atresia and intact ventricular septum

To identify developmental aspects and establish morphologic criteria useful for clinical recognition of sinusoids and coronary artery abnormalities in pulmonary atresia and intact ventricular septum, we studied 17 autopsy hearts with this lesion. Hearts from age- and weight-matched infants served as controls. There were two stillborn fetuses, 12 full-term neonates, and 3 infants. None of the eight hearts with normal or large-sized right ventricular chambers had sinusoids or coronary artery abnormalities. Five of nine hearts with small right ventricular chambers had sinusoids; all five lacked trabecular and outlet portions of the ventricle. Four of these five contained major coronary artery abnormalities: atrophy of one or both coronaries proximal to a communication between a sinusoid and the coronary artery. We conclude (1) there is a strong association between the presence of sinusoids and coronary anomalies, supporting the developmental concept of abnormal persistence of embryonic right ventricular sinusoid--coronary artery communications in pulmonary atresia and intact ventricular septum; (2) the absence of trabecular and outlet portions of the small right ventricle indicates a strong possibility of coronary artery abnormalities; and (3) this initial report of a fully-developed lesion in a mid-gestation fetus documents that the coronary artery problem may arise early in fetal life.

Operative balloon dilatation for pulmonary atresia with intact ventricular septum

In six infants with pulmonary atresia and intact ventricular septum operative balloon dilatation was used to achieve continuity between the right ventricle and the main pulmonary artery as the initial procedure. Two of the six subsequently needed an aortico pulmonary shunt. All six are alive and well.

Ventriculo-coronary micro-communications in pulmonary atresia and sequential changes of coronary arteries

In the present paper, numerous micro-communications between myocardial sinusoids and small branches of coronary arteries are studied which existed in a rudimentary right ventricle of a female neonate with pulmonary atresia and an intact ventricular septum, who was born on the 40th week of gestation. Cardioangiography revealed a large fistulous subepicardial communication. At autopsy, myocardium of the right ventricle appeared spongy with extensive sinusoid slits. In addition to the large communication which was connecting a deeply extending sinusoid of the right ventricle to the main trunk of the anterior descending artery, numerous micro-communications were found between myocardial sinusoids in the rudimentary right ventricle and intramural small branches of the coronary artery. Furthermore, morphometrical analysis demonstrated that the medias of the intramural arteries in both ventricles of the present case were significantly hypertrophic, as compared with those in the control cases without communications (p less than 0.05). These facts indicate the significance of hemodynamic factors on the persistence of embryonic sinusoid-coronary communication.

Concomitant valvotomy and subclavian-main pulmonary artery shunt in neonates with pulmonary atresia and intact ventricular septum

Our current approach to the management of neonates with pulmonary atresia and intact ventricular septum is to perform a transarterial pulmonary valvotomy through a left anterolateral thoracotomy followed by a polytetrafluoroethylene shunt between the left subclavian artery and the pulmonary trunk at the site of the pulmonary arteriotomy. From October, 1983, to December, 1985, 7 consecutive neonates with pulmonary atresia and intact ventricular septum were managed in this fashion. Mean age was 5.1 days (5 patients, less than 48 hours old), and mean weight was 3.3 kg (range, 2.5-4.3 kg). Right ventricular morphology was type I (tripartite) in 4 patients, type II (absent trabecular portion) in 2, and type III (absent trabecular and infundibular portions) in 1. The mean right ventricular to left ventricular peak systolic pressure ratio was 1.5. One patient who initially had valvotomy alone required a left subclavian-pulmonary trunk shunt the next day for hypoxemia. All other patients had a valvotomy and shunt during the same procedure. There were no operative or hospital deaths. Follow-up of 3.5 to 34 months (mean, 17.5 months) confirmed shunt patency in all patients. Three of 4 patients undergoing postoperative catheterization have shown good right ventricular growth; 2 have undergone successful repair at 10 and 23 months. There have been 3 late deaths at 3.5, 4, and 8 months. Two other patients are doing well and are awaiting postoperative catheterization. This procedure permits synchronous valvotomy and shunting without the need for cardiopulmonary bypass in these critically ill neonates.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary arterial abnormalities in pulmonary atresia with intact ventricular septum

The incidence and severity of abnormalities of the coronary arteries were evaluated in 35 necropsy patients with pulmonary atresia and an intact ventricular septum. Right ventricular to coronary artery fistulous connections were found in more than 60% of the cases. All patients with fistulous connections had histologic abnormalities of the coronary arteries. In 50% the lesions were mild, with medial and intimal thickening producing up to moderate luminal stenosis. In 50% there was loss of normal arterial wall structure and severe narrowing or obliteration of the arterial lumen. The coronary arterial fistulas and histologic abnormalities were prevalent in those with underdevelopment of the tricuspid valve and right ventricular cavity but were not found in patients with a normal or dilated tricuspid valve anulus. The coronary arterial abnormalities were found in more than 80% of patients with a tricuspid valve/mitral valve ratio less than 1. A single coronary artery occurred in 6 patients (17%) of this series. In 80% of those with 1 coronary artery arising from the other, the aberrantly arising coronary artery crossed anteriorly to the pulmonary artery and could be at risk in surgical attempts to reconstruct the right ventricular outflow. Aortography is recommended if the coronary arteries are not clearly delineated on ventricular cineangiocardiography.

Late right ventricular reconstruction following valvotomy in pulmonary atresia with intact ventricular septum

Experience over two decades in the surgical management of pulmonary atresia with intact ventricular septum demonstrates that eventual right ventricular (RV) reconstruction is possible in the majority of patients surviving valvotomy in infancy. Ten of 17 operative survivors of early valvotomy have eventually received a patch graft to the RV outflow tract, with no reoperative deaths (mean follow-up, 7.4 years). RV systolic pressures, suprasystemic prior to reoperation, are near normal after outflow patch reconstruction. Serial cineangiograms show evidence of RV growth by measurement of tricuspid annulus diameter (TAD), and demonstrate a rate of growth [d(TAD)/d(body length)] greater than a normal rate derived from autopsy data. The mean TAD growth rate is significantly greater than that of patients with less favorable ventricle types treated with a systemic-pulmonary shunt alone. Measurement of TAD is a useful method for following RV growth, and may aid in selecting patients for RV reconstruction.

Pulmonary atresia with intact ventricular septum: a quantitative cineventriculographic study of the right and left ventricular function

Quantitative cineventriculographic measurements (ventricular volumes, ejection fraction, and myocardial mass) were obtained in 15 neonates with pulmonary atresia and intact ventricular septum. There was a wide dimensional range for the right ventricle, from a reduced through normal to enlarged. A restrictive tricuspid valve (less than 12 mm) was associated with a small or diminutive right ventricle. A normal function of the right ventricle was present only in those cases with normal-sized chambers. The left ventricular end-diastolic volume was always greater than normal. The ejection fraction was normal only if a normal myocardial mass was present. Additional abnormalities were frequent in the myocardium of both ventricles, such as extreme thinning of the wall of the right ventricle and hypoplasia or fibroelastosis of the left ventricle. All these factors can lead to a poor surgical prognosis despite good anatomical correction.

Comprehensive management of pulmonary atresia with intact ventricular septum

The prognosis for patients with pulmonary atresia with intact ventricular septum is poor with or without conventional surgical intervention. Therefore, a comprehensive program of medical and surgical treatment is necessary to improve long-term outlook for these infants. Such a program consists of management of the neonate at initial presentation with prompt administration of prostaglandins and institution of a combination of surgical procedures (isolated pulmonary valvotomy, valvotomy plus modified Blalock-Taussig shunt, Blalock-Taussig shunt plus balloon atrial septostomy, or Blalock-Taussig shunt alone) depending on the results of morphological analysis of the right ventricle; this treatment regimen is designed to relieve hypoxemia, encourage right ventricular growth, and provide adequate egress of blood from the right atrium. Another important element of management is to perform follow-up hemodynamic and angiographic studies when the patient is between 6 and 12 months old to ensure that the objectives of the comprehensive program are being met. Finally, a definitive repair should be offered. This can be done by using or bypassing the right ventricle, depending on whether it can support the pulmonary circuit.