Anatomical variants in aortic atresia. Potential candidates for ventriculoaortic reconstitution.

Aortic valve atresia is usually associated with severe hypoplasia of the left ventricle and mitral apparatus. Palliative procedures, including atrial septectomy, pulmonary artery-aorta anastomosis, and pulmonary artery banding, have been performed in some patients. However, because of the distinct underdevelopment of the left heart, the long-term prognosis must be guarded even in the survivors of these procedures. Rarely, aortic valve atresia is found with adequate left heart chambers. Because very few of these patients are described, the clinical, angiocardiographic, and the pathological findings in two patients are presented, with comments on palliation in the neonatal period, and the potential for ventriculoaortic reconstitution.     

Technique of percutaneous laser-assisted valve dilatation for valvar atresia in congenital heart disease.

OBJECTIVE--To investigate the efficacy and safety of transcatheter laser-assisted valve dilatation for atretic valves in children with congenital heart disease. DESIGN--Prospective clinical study. SETTING--Supraregional paediatric cardiology centre. SUBJECTS--Eleven children (aged 1 day-11 years; weight 2.1-35.7 kg) with atresia of pulmonary (10) or tricuspid (one) valve underwent attempted laser-assisted valve dilatation as part of the staged treatment of their cyanotic heart disease. INTERVENTION--After delineating the atretic valve by angiography and/or echocardiography a 0.018 inch "hot tip" laser wire was used to perforate the atretic valve. Subsequently the valve was dilated with conventional balloon dilatation catheters up to the valve annulus diameter. RESULTS--Laser-assisted valve dilatation was successfully accomplished in nine children. In two neonates with pulmonary valve atresia, intact ventricular septum, and coexistent infundibular atresia the procedure resulted in cardiac tamponade: one died immediately and one later at surgery. During a follow up of 1-17 months (mean 11) two infants with pulmonary valve atresia and intact ventricular septum died (one with congestive cardiac failure). The remainder are either well palliated and do not require further procedures (three), or are awaiting further transcatheter or surgical procedures because of associated defects (four). CONCLUSIONS--Laser-assisted valve dilatation is a promising adjunct to surgery in this high risk group of patients. It may avoid surgery in some patients, and may reduce the number of surgical procedures in those requiring staged operations.     

Juxtaductal left pulmonary artery obstruction in pulmonary atresia.

The morphology of the central pulmonary artery was studied by selective angiography in 21 previously unoperated patients (aged 11 days-21 years, median 4 years) with pulmonary atresia associated with various types of congenital heart disease. Angiographic findings were confirmed at operation in 10 patients. There was juxtaductal obstruction of the left pulmonary artery in two thirds of the patients with complete atresia in a quarter. Six of seven patients without juxtaductal obstruction had pulmonary valve atresia, but all nine patients with juxtaductal stenosis had truncal atresia. No patient had stenosis of the right pulmonary artery.     

Juxtaductal left pulmonary artery obstruction in pulmonary atresia

The morphology of the central pulmonary artery was studied by selective angiography in 21 previously unoperated patients (aged 11 days-21 years, median 4 years) with pulmonary atresia associated with various types of congenital heart disease. Angiographic findings were confirmed at operation in 10 patients. There was juxtaductal obstruction of the left pulmonary artery in two thirds of the patients with complete atresia in a quarter. Six of seven patients without juxtaductal obstruction had pulmonary valve atresia, but all nine patients with juxtaductal stenosis had truncal atresia. No patient had stenosis of the right pulmonary artery.     

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.     

Thrombolytic therapy for right heart lesions.

Thrombolytic agents are accepted therapy for occlusion of coronary and peripheral arteries as well as for venous thromboses. Although the treatment of left heart prosthetic valve thrombosis has been evaluated, there are limited data showing the benefit of thrombolysis of right heart clots. Two patients with past histories of multiple cardiac operations were given fibrinolytic therapy for thrombosis involving right heart structures. The first patient had thrombosis of a prosthetic pulmonary valve. The second patient was a type IB tricuspid atresia who developed a Fontan duct stenosis and right atrial clot. Thrombolytic therapy may provide a safe alternative to surgical intervention for thrombosis of right heart structures and, even when incompletely effective, may provide additional time to prepare patients for surgical correction and possible protection against distal embolization during surgical intervention.     

Fistulous communications with the coronary arteries in the setting of hypoplastic ventricles

Neonates born with hypoplastic left heart syndrome now have a remarkably improved prognosis compared with the situation existing before the development of the Norwood sequence of operative procedures. Some of those born with hypoplastic right ventricles in the setting of pulmonary atresia with an intact ventricular septum, however, still have a relatively poor prognosis. In part this reflects the presence of fistulous communication between the cavity of the right hypoplastic right ventricle and the coronary arterial tree. Such fistulous communications are now increasingly recognised as being important in the setting of hypoplastic left heart syndrome. In this brief review, we describe the anatomy of the communications. Those found with hypoplastic right ventricles are seen most frequently when the cavity of the ventricle effectively represents only the inlet, this in turn reflecting mural overgrowth of the apical trabecular and outlet components during foetal development. This almost certainly reflects an earlier appearance of the pulmonary valvar lesion that promotes the cavitary hypoplasia. In those with hypoplastic left ventricles, the key feature differentiating those with fistulous communications is the presence of a patent mitral valve, since the left ventricle is typically no more than a virtual slit in postero-inferior ventricular wall in the setting of mitral valvar atresia or absence of the left atrioventricular connection.     

Pulmonary circulation in pulmonary atresia associated with the asplenia cardiac syndrome.

OBJECTIVE. The goal of this study was to determine the patterns of the pulmonary circulation in patients with pulmonary atresia and asplenia. BACKGROUND. The asplenic cardiac syndromes characteristically have complex cardiac anomalies including pulmonary stenosis or atresia. Definition of the pulmonary artery circulation and pulmonary venous connections is needed for consideration of surgical procedures. METHODS. In 35 patients, the sources of pulmonary blood flow, anatomic features of pulmonary arteries and pulmonary venous connections were determined from angiograms or autopsy specimens. RESULTS. The main pulmonary artery was absent or hypoplastic in 91% of patients; most had a ductus arteriosus. The right and left pulmonary arteries were confluent in 90% and usually of normal size (right 71%, left 63%). Total anomalous pulmonary venous connections were present in 38%. CONCLUSIONS. The anatomic features of the pulmonary arteries in pulmonary atresia associated with the asplenic cardiac syndrome are usually favorable for palliative surgical procedures. Total anomalous pulmonary venous connection may exist as a complicating factor.     

Coronary artery abnormalities and right ventricular histology in hypoplastic left heart syndrome.

OBJECTIVES. To determine whether right ventricular preservation is compromised in any anatomic subgroup of hypoplastic left heart syndrome, we assessed the coronary artery anatomy and myocardial histologic features of 151 postmortem specimens with hypoplastic left heart syndrome. BACKGROUND. Although previous studies have shown that coronary artery abnormalities are more prominent in the subgroup of patients who have a patent mitral valve and obstructed aortic valve, it has not been established that these abnormalities compromise right ventricular perfusion. METHODS. Eighty-nine specimens with a patent mitral valve and aortic atresia, 52 with mitral and aortic atresia and 10 with patent mitral and aortic valves were examined. Histologic sections of the right ventricle, left ventricle and coronary arteries were obtained from 64 study hearts and 5 control hearts. RESULTS. Gross coronary anomalies included coronary-cameral communications (n = 29), single left coronary artery (n = 2), single right coronary artery (n = 1) and tortuosity (n = 19). Coronary-cameral communications and tortuosity were significantly associated with the subgroup that had mitral hypoplasia and aortic atresia. Coronary artery wall thickness relative to lumen diameter was not different among the subgroups. No areas of coronary artery stenosis or interruption were discovered. Although endocardial fibroelastosis of the left ventricle was strongly associated with the mitral hypoplasia and aortic atresia group, the right ventricular histologic findings were similar in all subgroups and were not differentially affected by older age. CONCLUSIONS. Although the incidence of coronary abnormalities is greater in patients with mitral hypoplasia and aortic atresia, in this study there was no apparent difference in perfusion of the right ventricle among the anatomic subgroups of hearts with hypoplastic left heart syndrome.     

Double inlet ventricle. Lung biopsy findings and implications for management.

The lung was biopsied in 20 children with double inlet ventricle and pulmonary hypertension aged 2 months to 14 years. Eleven patients had two patent atrioventricular valves, three atresia of the right valve, and six hypoplasia of the left valve. Severe pulmonary arterial medial hypertrophy occurred in the nine children less than 1 year of age. The findings did not suggest a period of normality after birth when the pulmonary artery might have been banded most effectively. Of the 11 older patients, eight had medial hypertrophy and three intimal proliferation with medial atrophy. Six patients with medial hypertrophy had some reduction in pulmonary arterial pressure after banding. It is recommended that the pulmonary artery be banded as early as possible, and rebanded early if a satisfactory result is not obtained, particularly in patients destined for a Fontan-Kreutzer procedure. Early atrial septectomy should reduce the arterial and venous abnormalities seen in left atrioventricular valve hypoplasia.     

Selective aortic root angiography in the hypoplastic left heart syndrome.

Selective aortic root angiography was performed in 18 patients with the clinical diagnosis of hypoplastic left heart syndrome in order to allow more precise correlation with echocardiography. Aortic valve atresia and severe hypoplasia of the left heart chambers subsequently were substaniated at necropsy in each instance. Wide variation in the size and shape of the aortic root and ascending aorta was demonstrated angiographically in these patients. In some patients, despite aortic valve atresia, the dimensions of the aortic root and sinuses of Valsalva at angiography were almost normal. In addition, this technique allowed the demonstration of primitive vascular communications between the coronary artery and left ventricular cavity in 1 patient (coronary-cameral fistula). The realization that the aortic root may approach nearly normal size in some patients with the hypoplastic left heart syndrome is essential to the echocardiographic diagnosis of this disease and to the differential diagnosis from other cardiac and noncardiac causes of severe neonatal congestive heart failure.     

Truncal or aortic valve stenosis in functionally single arterial trunk: A clinical,hemodynamic and pathologic study of six cases

Stenosis of the semilunar valve in the presence of a functionally single arterial trunk is uncommon. Three patients with truncus arteriosus, two with tetralogy of Fallot and pulmonary atresia and one with pulmonary atresia and intact septum were diagnosed as having stenosis of the truncal or aortic valve on the basis of clinical, echocardiographic, hemodynamic and angiocardiographic findings. Echocardiograms consistently showed multiple diastolic closure lines and abnormal semilunar valves in addition to the aortic override in five patients and hypoplastic right ventricle in the patient with pulmonary atresia and intact septum. Peak systolic gradients between the left ventricle and truncus (or aorta) at cardiac catheterization ranged from 20 to 47 mm Hg. Retrograde aortography confirmed a domed and stenotic semilunar valve. Cyanosis was progressive in the three patients with pulmonary atresia. Two patients had arterial anastomosis, and one had a right ventricle-pulmonary arterial graft in addition to aortic valvotomy. One of the three patients with truncus arteriosus underwent complete repair in addition to truncal valvotomy but he died in the postoperative period. The other two patients with truncus arteriosus died of intractable congestive cardiac failure before surgical intervention.It is suggested that the presence of semilunar valve stenosis in these patients adversely affects the prognosis. The myocardium is already jeopardized as a result of hypoxia in pulmonary atresia and left ventricular diastolic overload in patients with truncus arteriosus. The added burden of semilunar valve stenosis may further compromise the functional status of the myocardium.     

Transcatheter management of cyanotic congenital heart defects: a review.

In this review, the role of transcatheter methods in the management of cyanotic congenital heart defects is discussed. In patients with interventricular right-to-left shunting secondary to pulmonary outflow tract obstruction (most commonly tetralogy of Fallot), balloon dilatation may be an effective palliative procedure in a substantial proportion of patients, obviating the need for a palliative shunt. We would recommend this if the patient's size or cardiac anatomy makes that patient an unsuitable candidate for safe total surgical correction. Infundibular myectomy with atherectomy catheter in tetralogy of Fallot patients may become a useful adjunct in the management of these infants. Cyanotic children with interatrial right-to-left shunt secondary to severe valvar pulmonary stenosis respond to balloon pulmonary valvuloplasty in a manner similar to that seen with isolated pulmonary valve stenosis. In these patients, balloon valvuloplasty is the treatment of choice and may be corrective in most cases. In patients with a narrowed Blalock-Taussig shunt, balloon angioplasty may improve pulmonary oligemia and systemic arterial hypoxemia and may obviate the need for a second systemic-to-pulmonary artery shunt. Balloon angioplasty is recommended if the patient's cardiac defect is not amenable to surgical correction at a low risk either because of the size of the patient or because of the complexity of the cyanotic heart defect. In patients with pulmonary valve atresia, initial opening of the atretic pulmonary valve by either laser or surgery with subsequent balloon dilatation is potentially beneficial in reducing the total number of surgical procedures that these children are likely to require. However, further clinical trials are needed prior to their general use.     

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.     

Double inlet ventricle. Lung biopsy findings and implications for management

The lung was biopsied in 20 children with double inlet ventricle and pulmonary hypertension aged 2 months to 14 years. Eleven patients had two patent atrioventricular valves, three atresia of the right valve, and six hypoplasia of the left valve. Severe pulmonary arterial medial hypertrophy occurred in the nine children less than 1 year of age. The findings did not suggest a period of normality after birth when the pulmonary artery might have been banded most effectively. Of the 11 older patients, eight had medial hypertrophy and three intimal proliferation with medial atrophy. Six patients with medial hypertrophy had some reduction in pulmonary arterial pressure after banding. It is recommended that the pulmonary artery be banded as early as possible, and rebanded early if a satisfactory result is not obtained, particularly in patients destined for a Fontan-Kreutzer procedure. Early atrial septectomy should reduce the arterial and venous abnormalities seen in left atrioventricular valve hypoplasia.     

Coagulation studies in rheumatic heart disease.

The clotting characteristics of pulmonary and systemic blood were studied in 10 patients with chronic rheumatic mitral valve disease complicated by atrial fibrillation and in seven patients with aortic valve disease in sinus rhythm. A haemostatic basis for the association of rheumatic mitral valve disease with thrombotic emboli was sought. Both groups of patients showed differences in platelet function between pulmonary and systemic arterial blood. In patients with mitral valve disease aggregation of platelets was significantly greater in pulmonary than in systemic arterial blood at rest; the converse was true during exercise. In aortic valve disease platelet aggregation was greater in systemic than in pulmonary arterial blood at all times. Only the patients with mitral valve disease showed changes in blood coagulation during passage through the lungs and left heart; there was a small but statistically significant shortening in partial thromboplastin time in systemic as compared with pulmonary arterial blood both at rest and during exercise. Similarly, the effects of exercise on the various haemostatic factors measured were largely confined to the patients with mitral valve disease; in these patients exercise stimulated an increase in factor VIII in pulmonary arterial blood and an increase in platelet adhesiveness and aggregability in left heart blood. These changes provide a basis for the suggestion that in patients with rheumatic mitral valve disease, unlike those with aortic valve disease, there is an increased thrombotic tendency in blood in the left heart which is particularly pronounced during exercise.     

Univentricular heart, common atrium, single atrio-ventricular valve--is it possible in humans?

Two extremely rare cases of adults with univentricular hearts of right ventricular morphology are presented. Pathogenesis and pathophysiology of univentricular circulation as well as anatomic variants, short information on prognosis and management are briefly discussed. Echocardiographic diagnosis of univentricular heart is described. The first case was a 23-year-old housewife with univentricular heart, functionally common atrium, single atrio-ventricular valve of tricuspid morphology, transposition of great arteries and significant subvalvular pulmonary stenosis. The second case was a 19-year-old student with univentricular heart with moderately depressed systolic function, common atrium, single atrio-ventricular valve of tricuspid morphology, mitral atresia, and non-communication residual left ventricle. Both patients led a normal life with little to moderate limitations of everyday activity.     

Aortic valve atresia: a new classification based on necropsy study of 73 cases.

Certain clinical and morphologic observations are described in 73 necropsy patients with aortic valve atresia. The mean age at death was 5 days; 80 percent died during the first week of life, and 70 percent were boys. Of the 73 patients, 69 (95 percent) had a hypoplastic left ventricle with intact ventricular septum and either an atretic (25 patients) or hypoplastic (44 patients) mitral valve. The other four patients had a well developed left ventricle with one or more defects in the ventricular septum and either an atretic (one patient) or well developed (three patients) mitral valve. Review of previous reports on aortic valve atresia disclosed that a well developed left ventricle or ventricular septal defect in association with absence of the aortic valve was extremely rare. A new classification for aortic valve atresia is presented based on the status of the ventricular septum, which in turn appears to determine the size of the left ventricular cavity. The predilection for male subjects for all types of aortic valve disease, including atresia, is emphasized.     

Absent tricuspid valve with aortic atresia in mixed levocardia (atria situs solitus, L-loop). A hitherto undescribed entity.

Clinical, angiographic and pathologic features are described in a 36-hour-old male infant with mixed (discordant) levocardia, aortic valve atresia, absent tricuspid (left atrioventricular) valve and resultant massive cardiomegaly. This is the first reported case of this type of complex in a heart with discordant chambers. A possible embryologic explanation is offered for the concomitant presence of semilunar valve atresia and absence of the tricuspid valve.     

Initial and late results after catheter intervention for neonatal critical pulmonary valve stenosis and atresia with intact ventricular septum: a technique in continual evolution.

Critical pulmonary valve stenosis or atresia with intact ventricular septum is a rare congenital cardiac defect that can be technically difficult to alleviate in the catheterization laboratory. Over the past 10 years, several techniques and modifications with variable results have been advocated to facilitate the valvuloplasty procedure. This report describes a single operator's experience using various techniques in 28 neonates with critical pulmonary stenosis or atresia who were considered candidates for transcatheter intervention. The first two patients underwent a gradational balloon valvuloplasty approach that resulted in prolonged fluoroscopy exposure. Thereafter, a "snare assisted" umbilical artery approach was developed which facilitated the valvuloplasty procedure and resulted in significantly fewer balloons used and shorter fluoroscopy times. Early in our experience, stiff guidewire perforation of atretic pulmonary valves was used, whereas in our last two patients, a simplified perforation technique with a new 0.9-mm excimer laser catheter was used. Late echocardiographic and clinical follow-up evaluation in 27 patients demonstrates persistent gradient relief, resolution of tricuspid valve insufficiency, and elimination of right to left shunting at the atrial level. Balloon valvuloplasty is the treatment of choice for critical pulmonary valve stenosis or atresia with intact ventricular septum. When necessary, the use of umbilical artery "snare assistance" facilitates the valvuloplasty technique and shortens procedure time while laser perforation is currently preferable for perforation of the atretic pulmonary valve.