Congenital pulmonary atresia with intact ventricular septum clinicopathologic correlation of two anatomic types

Fetal pulmonary valve stenosis or atresia with intact ventricular septum: Predictors of need for neonatal intervention

OBJECTIVES

To compare the fetal echocardiographic measurements and neonatal outcome of fetuses with diagnosis of critical pulmonary stenosis (CPS/IVS) and pulmonary atresia with intact ventricular septum (PA/IVS) to identify the predictors of neonatal ductus dependence and the need for neonatal intervention.

METHODS

Forty-four fetuses with a diagnosis of membranous PA/IVS or CPS/IVS referred to Shanghai Xinhua Hospital Affiliated to Shanghai Jiaotong University between June 2009 and November 2014 were respectively analyzed. We analyzed their fetal and pediatric echocardiographic features and clinical features after birth.

RESULTS

Among the 29 infants in the final analysis, 19 were ductal dependent and were diagnosed as CPS/IVS or PA/IVS after birth. Ten patients with fetal CSP/IVS were ductal independent and were diagnosed as pulmonary stenosis after birth. In midtrimester, significance was only detected in pulmonary valve (PV) regurgitation between 2 groups (P = .009). The fetuses with PV regurgitation in midtrimester were more likely to be ductal independent (odds ratio = 6.67; P = .010) than those with absence of PV regurgitation in the midtrimester scan. In late trimester, the infants in ductus-independent group had better fetal right ventricular development than those in ductus dependent group. The right ventricle over left ventricle length ratio in last scan over 0.86 had the best capability in predicting ductus independence during neonatal period with help of receiver-operating characteristic curve and the logistic regression analysis.

CONCLUSION

Among fetuses with pulmonary valve stenosis and right ventricle dysplasia at the time of first fetal echo in midtrimester, use of pulmonary valve regurgitation can identify who will be ductal dependent at births. In late trimester, right ventricle over left ventricle length ratio less than 0.86 had the best capability of predicting neonatal ductal dependence. Fetuses with reversed ductus arteriosus flow direction in late trimester were more likely to be ductus dependent after birth.

Excimer laser ablation for valvular angioplasty in pulmonary atresia and intact ventricular septum

BACKGROUND AND OBJECTIVES

The prognosis for infants with pulmonary atresia and intact ventricular septum (PA/IVS) is poor and they present a major management challenge. Mechanical penetration of the atretic pulmonary valve is an applicable option for decompression of the right ventricle and optimization of left ventricular function. The utilization of laser energy for debulking and vaporization of the atretic valve tissue is a relevant approach due to the potential for controlled, precise mode of energy distribution.

STUDY DESIGN/PATIENTS AND METHODS

A 4-month-old female with PA/IVS whose failure to thrive was accompanied by critical hemodynamic abnormalities received successful percutaneous pulmonary valve plate ablation by a 0.9 mm pulsed-wave ultraviolet excimer laser catheter (308 nm wavelength, fluence 50 mJ/mm(2); 30 Hz). A "step-by-step" lasing technique was applied whereby the tip of the emitting laser catheter is advanced ahead of a guide wire that serves mainly as support for positioning of that catheter.

RESULTS

Adequate penetration of the atretic tissue enabled introduction of balloon dilations resulting in patency of the atretic valve, decompression of the right ventricle, improved right and left ventricular hemodynamics, and oxygenation. To further investigate the effect of excimer laser energy on atretic valvular tissue this laser was applied in a specimen of heart from an infant who died because of PA/IVS. Histopathologic examination of the irradiated tissue revealed no laser-induced injury to the pulmonary valve.

CONCLUSIONS

Thus, laser ablation and penetration of an atretic pulmonary valve is feasible and safe. The penetration of the atretic valve with the laser catheter enables subsequent introduction of various sizes balloon dilations. The application of available laser sources for treatment of congenital heart diseases is reviewed.

Pulmonary Atresia with Intact Ventricular Septum

The prognosis for patients with pulmonary atresia with intact ventricular septum is poor with and without conventional surgical treatment. Because of this reason, a comprehensive program of medical, transcatheter, and surgical treatment is necessary to improve the long-term outlook of these infants. Algorithms of management plans should be developed based on the presence of right ventricular-dependent coronary circulation as well as size and morphology of the right ventricle. In a tripartite or bipartite right ventricle, transcatheter radiofrequency perforation is preferable. Alternatively, surgical valvotomy may be performed. Augmentation of pulmonary blood flow by prolonged infusion of prostaglandin E(1), stenting the ductus, or a surgical modified Blalock-Taussig shunt may be necessary in some of these patients. In patients with a unipartite or very small right ventricle or a right ventricular-dependent coronary circulation (Tricuspid valve Z score < -2.5), augmentation of pulmonary flow along with atrial septostomy should be undertaken. Follow-up studies to determine the feasibility of biventricular repair should be undertaken and, if feasible, surgical or transcatheter methods may be used to achieve the goals. If not suitable for biventricular repair, one-ventricle (Fontan) or one and one-half ventricular repair should be considered. Comprehensive and well-planned treatment algorithms may help improve survival rate.

Severe tricuspid regurgitation 14 years after diagnosis of “transient neonatal tricuspid regurgitation”

A 14 year old girl presented with severe tricuspid regurgitation after she was diagnosed with “transient tricuspid regurgitation of the newborn”. In the neonatal period she had presented with severe tricuspid regurgitation without an obvious underlying anatomical cause. This spontaneously regressed during the first months of life. She was dismissed from follow up at the age of 5 years after complete normalisation of the clinical and echocardiographic examination. The subsequent evolution and management of the patient, as well as the possible pathogenesis responsible for the unusual clinical course, is discussed. This case stresses the importance of long term follow up of patients with transient tricuspid regurgitation.

SINGLE CORONARY ARTERY WITH FISTULOUS COMMUNICATION. REPORT OF TWO CASES

Two cases of single coronary artery with fistulous communication (one to the right ventricle and one to the pulmonary artery) are presented as extremely rare combinations of two rare coronary anomalies. There have been two, previous, similar cases reported in the medical literature.

Assessment of fetal pulmonic stenosis by ultrasonography

This study was designed to determine (1) the value of Doppler echocardiography in depicting the presence of a fetal pulmonary stenosis, (2) its reliability in the assessment of the severity of the lesion, and (3) the usefulness of additional markers from the left side of the heart as criteria of severity. Fourteen pregnant ewes were included in this study (gestational age, 90 to 120 days). Banding of the fetal main pulmonary artery created mild (n = 3), moderate (n = 3), and severe (n = 5) stenosis. Three lambs were sham operated. Intrauterine fetal Doppler echocardiographic data obtained 15 days after surgery were compared with preoperative values. Peak velocities recorded through the band increased linearly from baseline in the groups with mild and moderate stenosis but did not show any further increase in the group with severe stenosis. Compared with the sham-operated group, right ventricular output in the group with stenosis was either similar or reduced significantly. The increase in right ventricular free wall thickness was significantly greater in the groups with stenosis compared with that of the sham-operated group; the correlation with the degree of severity was r = 0.65 and p < 0.05. A A stronger positive correlation was found between the severity of stenosis and aortic valve diameters: r = 0.82 and p < 0.01. The strongest correlation was found for right ventricular/left ventricular outputs (r = 0.92; p < 0.001). Thus Doppler peak velocities through the obstruction can help detect pulmonic stenosis but are not reliable for the assessment of its severity during fetal life. Other ultrasound measurements such as the size of the aortic anulus and especially the ratio of right ventricular/left ventricular output could be used as sensitive markers of the severity of stenosis.

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.

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.

Transient neonatal tricuspid regurgitation: a Doppler echocardiographic study of three cases

Three patients with normal hearts and no pulmonary abnormality had neonatal tricuspid regurgitation causing cardiorespiratory distress and cyanosis. The signs of tricuspid regurgitation resolved over a few weeks. In the acute phase echocardiography showed gross dilatation of the right atrium and ventricle. The interatrial septum bulged into the left atrium during the whole cardiac cycle. Doppler echocardiography showed clinically significant tricuspid regurgitation, a right to left shunt through the foramen ovale, reduced flow through the pulmonary valve, and in two patients ductal flow into the pulmonary artery. In one patient tricuspid regurgitation was so great that it impeded the opening of the pulmonary valve and produced functional "atresia" of the pulmonary valve. The presence of regurgitant blood flow through the pulmonary valve showed that the "atresia" was functional rather than organic. Doppler echocardiographic study is useful in distinguishing functional neonatal tricuspid regurgitation from structural abnormality of the tricuspid valve.

Ventriculocoronary connections in hypoplastic right heart syndrome: autopsy serial section study of six cases

Myocardial sinusoids communicating with the coronary systems occur in pulmonary atresia with intact ventricular septum. To test the hypothesis that the extent of ventriculocoronary connections correlates with the degree of right ventricular outflow obstruction as evidenced by clinical, angiographic and gross anatomic findings, a serial section study of six human autopsy hearts representing a spectrum of hypoplastic right heart was undertaken. Slides were evaluated for the presence and extent of ventriculocoronary connections, associated developmental abnormalities and secondary changes in the ventricular walls. Whereas extensive blind-ended deep sinusoids were a feature of all five cases with unrelieved obstruction, ventriculocoronary connections were identified in three. Changes that suggested ongoing remodeling provide new evidence for the postnatal temporal evolution of these anomalous communications. The regional distribution of myofiber disarray in hypoplastic right heart supports the concept that vascularization parallels myocardial organization in the developing human heart.

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.

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.

Myocardial ischemia in patients with pulmonary atresia and intact ventricular septum

Children who die after operation for pulmonary atresia and intact ventricular septum may have myocardial ischemia. The relation between histologic evidence of myocardial ischemic injury and the presence of a right ventricle to coronary artery fistula, coronary artery dysplasia and operation in 17 autopsy specimens was assessed. Age at death ranged from 1 day to 16 years (median, 11 days). Of the 17 hearts, 6 (35%) had right ventricle to coronary artery fistulas, 5 of which had coronary artery dysplasia. In three cases, there was segmental or complete absence of a coronary artery. Ischemia was present in four of these six hearts, two of which had right ventricular outflow reconstruction. Six of the 11 hearts without right ventricle to coronary artery fistulas also had myocardial ischemia. Of these six cases, four had right ventricular outflow reconstruction and two had shunt operations. Death occurred from 1 to 8 days (mean 3) after operation. Hearts with pulmonary atresia and intact ventricular septum may have myocardial ischemia with or without either right ventricle to coronary artery fistulas or coronary artery dysplasia. Myocardial ischemia may occur after right ventricular outflow reconstruction or shunt operations. Thus, myocardial ischemia occurs commonly in patients with pulmonary atresia and intact ventricular septum and is not always related to coronary abnormalities or operation.

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.

Two-dimensional echocardiographic evaluation of right ventricular size and function in newborns with severe right ventricular outflow tract obstruction

Critical pulmonary stenosis or atresia with intact ventricular septum represents a congenital cardiac lesion for which the long-term prognosis appears to depend partly on the size of the right ventricle. Thus, the capability of noninvasive assessment of right ventricular size to predict operative outcome was examined in 15 infants (aged 1 to 30 days, mean 5.6) with severe right ventricular outflow tract obstruction (either critical pulmonary stenosis [7 patients] or pulmonary atresia with intact ventricular septum [8 patients]). Using echocardiography in two orthogonal subxiphoid views, right ventricular volume, wall thickness, area change fraction, ejection fraction and tricuspid anulus dimension were measured. All patients with a normalized right ventricular enddiastolic volume of less than 5 ml/m2 and a normalized tricuspid anulus dimension of less than 1.0 cm/m2/3 required a shunt operation. Only one patient with a volume of more than 6 ml/m2 and a normalized tricuspid anulus dimension of more than 1.4 cm/m2/3 required more than relief of right ventricular outflow tract obstruction. In this patient, residual severe pulmonary stenosis necessitated the shunt procedure. One patient with a volume of more than 6 ml/m2 had an anulus diameter of less than 1.4 cm/m2/3 and one patient with an anulus diameter of more than 1.4 cm/m2/3 had a volume of less than 6 ml/m2; both required shunt procedures. It therefore appears that if either the ventricular volume or tricuspid anulus size is excessively small, a shunt procedure is necessary. Wall thickness, area change fraction and ejection fraction measurements were not significantly correlated with right ventricular volume or postoperative outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Surgical management of hypoplastic right ventricle with pulmonary atresia or critical pulmonary stenosis and intact ventricular septum

Our experience with the surgical management of hypoplastic right ventricle with intact ventricular septum includes 26 patients with pulmonary atresia and 4 with critical pulmonary stenosis. Group 1 consisted of 8 neonates managed initially by transventricular valvotomy; 6 later required a secondary procedure, with 100% survival. Group 2 had 11 neonates managed by aorta-pulmonary artery shunting without operative death. However, only 3 have survived over the long term and 1 has required an additional shunt procedure. Group 3 had 9 infants who underwent concomitant valvotomy and shunting. There were 4 operative deaths and 1 late death. Finally, Group 4 included 2 infants managed by primary repair at 3 days and 6 days old with prosthetic enlargement of the right ventricle; 1 required the addition of a shunt. Both are alive. Seven of the 15 patients in Groups 1, 2, and 3 who survived neonatal palliative procedures have undergone reparative operations. Two had no growth of the right ventricle and underwent repair after conversion to tricuspid atresia, by a Fontan procedure. Five had prosthetic enlargement of the right ventricle in childhood with 1 late death. Findings of this review were as follows: (1) effective palliation of pulmonary atresia and intact ventricular septum or critical pulmonary stenosis with cavitary hypoplasia of the right ventricle is rare unless transventricular flow can be established; (2) establishment of transventricular flow produces a high incidence of cavitary "growth," which permits later repair; (3) the Fontan operation is available for repair in patients who have no cavitary growth; and (4) when all three portions of the right ventricular cavity can be identified by angiography, a primary repair can be performed in the neonatal period with a good long-term prognosis.

Right ventricular infarction with cardiac rupture in an infant with pulmonary valve atresia with intact ventricular septum

This report describes an 8 day old infant with pulmonary valve atresia, hypoplastic and hypertensive right ventricle and myocardial sinusoid-left anterior descending coronary artery connections. A large right ventricular sinusoid complex developed that was associated with transmural right ventricular necrosis and cardiac rupture. This is the first report to document transmural myocardial infarction and rupture in pulmonary valve atresia with intact septum, and this condition should be added to the causes of myocardial infarction in infancy. A reduced number of caliber of sinusoid-coronary artery channels may be responsible for right ventricular damage in this condition.

Evaluation and surgical treatment of pulmonary atresia and intact ventricular septum in infancy

The initial surgical approach to the infant with pulmonary atresia and intact ventricular (PA-IVS) is to establish an adequate source of pulmonary blood flow and, when possible, relieve right ventricular (RV) outflow obstruction. The selection of patients for pulmonary valvotomy, alone or in combination with a systemic-pulmonary arterial shunt, depends on the presence of an RV outflow tract and the adequacy of the RV chamber. To evaluate the size of the RV cavity in PA-IVS, an RV index (RVI) was developed using biplane angiographic measurements of the sum of the tricuspid valve annulus and the RV inflow and the RV outflow tracts. The RVI was normalized by relating it to the aortic diameter (Ao) at the diaphragm (RVI/Ao). The RVI/Ao was 13.5 +/- 1.4 in 20 control subjects and only 7.3 +/- 2.6 in 26 PA-IVS patients (p less than 0.001), and was within the normal range in only two of the 26. Since 1976, pulmonary valvotomy plus a Blalock-Taussig shunt has been performed in 10 infants, with one death. Serial cardiac catheterizations in five of nine survivors demonstrated substantial RV growth in all, with the RVI/Ao increasing from an average of 8.0 to 12.5. In contrast, patients who underwent a shunt alone had no change in RV cavity size. We conclude that pulmonary valvotomy may be performed successfully in most PA-IVS patients, but usually must be combined with a systemic-pulmonary shunt. In a small minority of patients, a normal RV cavity, as evidenced by an RVI/Ao greater than or equal to 11, appears to be sufficient to sustain adequate pulmonary blood flow after valvotomy alone. The RVI/Ao ratio is a simple method of quantitatively evaluating RV cavity size and is helpful in planning the initial surgical approach for these infants.

Pulmonary atresia with and without ventricular septal defect: a different etiology and pathogenesis for the atresia in the 2 types?

In 15 of 20 hearts of neonates with pulmonary atresia and intact septum (PA-IVS) and in 4 with critical pulmonary stenosis, the pulmonary valve consisted of 3 fused cusps. One of the 11 patients with a ventricular septal defect (PA-VSD) had a well-developed pulmonary root; in 8 the pulmonary trunk arose from a dimple. Two had a bicuspid valve. In 10 of the 20 patients with PA-IVS and in those with critical stenosis, the diameter of the pulmonary trunk was normal or larger than normal. The authors believe that this is related to flow through an initially patent pulmonary valve and, perhaps more importantly, to poststenotic dilatation. In all hearts with PA-VSD, the pulmonary trunk was very small. In the patients with PA-IVS and a normal-sized pulmonary trunk and in 3 with critical pulmonary stenosis, the morphology of the ductus arteriosus was normal, suggesting that even in the former the valve was patent before birth, allowing forward flow. In all patients with small pulmonary trunk, the ductus was long, tortuous, and originated from the aortic arch in a proximal position, suggesting that reversal of flow had occurred early in development. The authors postulate that in patients with ventricular septal defect (VSD), the pulmonary ostium becomes atretic early in development, at or shortly after partitioning of the truncoconal part of the heart has taken place but before closure of the ventricular septum. In patients with intact ventricular septum, on the other hand, atresia very likely occurs sometime after cardiac septation has been completed. In these cases the pulmonary atresia may be due to a prenatal inflammatory process, rather than representing a true congenital malformation.

Pulmonary atresia with intact ventricular septum and ventriculocoronary communications: surgical significance

The first stage of a repair of pulmonary atresia with intact ventricular septum (type I) was attempted in a 2-day-old infant. At surgery, decompression of the hypertensive small right ventricle was followed by a sudden loss of myocardial contractility and death. Postmortem examination revealed a fistula with a large orifice in the right ventricular infundibulum that communicated directly with the left main coronary artery. Severe hypertensive changes indicative of abnormally high perfusion pressure were noted in the distal left coronary artery branches. The clinical course suggests that the effect of relieving right ventricular outflow obstruction was a reduction of left main coronary artery blood flow, resulting in fatal intraoperative myocardial ischemia. This unusual case draws attention to the anomalous ventriculocoronary communications often present in pulmonary atresia and their potential for limiting a successful surgical repair.

Development of the ductus arteriosus in right ventricular outflow tract obstruction

We studied the morphology of the ductus arteriosus in 14 infants, ages 2--90 days. Eight (group 1) had pulmonary atresia (structural and functional) with an intact interventricular septum; six (group 2) had pulmonary atresia with a ventricular septal defect. The inferior angle of the ductus arteriosus at the aortic junction was measured in each patient. In group 1, this angle was obtuse in all but one patient. In group 2, the angle was acute in all. Further study of intracardiac anatomy suggested that in group 1, the obtuse inferior angle of the ductus arteriosus was the result of a late and progressive obstructive phenomenon that allowed normal right-to-left flow through the ductus arteriosus during much of fetal life. In group 2, the direction of ductus arteriosus flow (normally from the pulmonary trunk to the aorta) was reversed, and flowed from the aorta to the pulmonary trunk. This reversal of flow was probably of early onset in the fetus, the aorta receiving the total combined ventricular output, and produced a small ductus arteriosus with an acute inferior angle. It is extremely important not to rule out pulmonary atresia with an intact interventricular septum when aortography in the newborn shows a normal-sized ductus arteriosus with an obtuse inferior angle. Despite existing pulmonary atresia, these patients have neither a hypoplastic right ventricle nor discontinuity of the right ventricle with the pulmonary artery.

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

Right ventricular growth was assessed angiocardiographically in 18 patients with pulmonary atresia, intact ventricular septum, and hypoplastic and hypertensive right ventricle. A variety of surgical procedures were performed. In only 12 patients (66.7%) was right ventricular-pulmonary artery continuity achieved (group 1). Nine of these 12 patients persisted with systemic or suprasystemic right ventricular pressures. Among the six patients in whom right ventricular-pulmonary artery continuity was not achieved (group 2), all maintained suprasystemic right ventricular pressures. Right ventricular growth was assessed in groups 1 and 2. The patients were also subdivided according to the qualitative degree of tricuspid regurgitation as determined angiocardiographically on right ventricular cineangiocardiograms at the preoperative catheter study. Right ventricular growth to normal levels as evidenced by change in right ventricular end-diastolic volume was rarely observed in group 2 patients. Among the four patients with severe tricuspid regurgitation and a large tricuspid valve, right ventricular growth to normal levels was achieved whether they were in group 1 or group 2. Right ventricular growth is thus predicated on numerous morphologic factors in these patients. However, reconstitution of right ventricular-pulmonary artery continuity and a nonobstructive tricuspid valve are probably two of the more important factors.

Morphological variations in pulmonary atresia with intact ventricular septum

The morphological features of a series of 37 specimens of pulmonary atresia with intact ventricular septum were reviewed with particular emphasis on features which might influence the results of pulmonary valvotomy. The degree of right heart hypoplasia was quantified by measuring right and left heart dimensions and comparing them with 20 normal infant hearts. Right ventricular cavity size was usually smaller than normal but constituted a spectrum ranging from tiny to a dilated ventricle larger than normal. There was a positive correlation between triscuspid annular size and right ventricular size but no correlation between the size of the pulmonary artery and the right ventricle. Successful pulmonary valvotomy with subsequent adequate right ventricular function would have been precluded by a tiny right ventricular cavity or infundibular atresia in 14 specimens and by severe tricuspid stenosis or regurgitation in an additional 4. Severe right or left ventricular endocardial fibroelastosis may have adversely affected ventricular function in several others. Ten specimens displayed convex bulging of the left ventricular septal surface. If these these anatomical findings are representative for the condition as a whole, they provide a good explanation for its disastrous prognosis.

Massive congenital tricuspid insufficiency in the newborn

Three cases of massive congenital tricuspid incompetence in the newborn are reported and discussed from diagnostic, pathologic and etiologic points of view. The diagnosis is important as cases have been reported with spontaneous resolution.

Congenital tricuspid incompetence simulating pulmonary atresia with intact ventricular septum: a report of two cases

Two infants with isolated congenital tricuspid incompetence appeared to have associated right ventricular outflow tract obstruction at diagnostic evaluation, including catheterization and cineangiography. One infant died during surgery; the other improved rapidly and survived with medical therapy. We discuss the problem of establishing the presence of patency of the right ventricular outflow tract in infants with massive tricuspid incompetence and outline an approach to the management of infants whose diagnosis remains unclear even after careful evaluation.

Congenital tricuspid insufficiency

This is a case report of a 16-year-old male with moderate mitral disease, probably rheumatic, and with severe tricuspid insufficiency, which at surgery appeared to be a congenital malformation of the tricuspid valve (absence of the anterior leaflet). A tricuspid heterograft was successfully inserted. The symptoms of congenital tricuspid insufficiency are discussed, and this entity is differentiated from other causes of tricuspid insufficiency.