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.     

Absence of the aortic valve cusps with mitral atresia, normal left ventricle, and intact ventricular septum

A case of a previously unreported anomaly is presented in which absence of the aortic valve cusps, mitral atresia, a normal left ventricle, and an intact ventricular septum were diagnosed by cross sectional echocardiography. The development of a normal left ventricle, rather than the hypoplastic ventricle usually associated with mitral atresia, is explained by filling of the ventricular cavity via the regurgitant aortic valve.     

Absence of the aortic valve cusps with mitral atresia, normal left ventricle, and intact ventricular septum.

A case of a previously unreported anomaly is presented in which absence of the aortic valve cusps, mitral atresia, a normal left ventricle, and an intact ventricular septum were diagnosed by cross sectional echocardiography. The development of a normal left ventricle, rather than the hypoplastic ventricle usually associated with mitral atresia, is explained by filling of the ventricular cavity via the regurgitant aortic valve.     

Coronary arterial abnormalities in pulmonary atresia with intact ventricular septum diagnosed during fetal life

OBJECTIVES: To establish the prevalence of coronary arterial abnormalities in mid-trimester fetuses with pulmonary atresia with intact ventricular septum, and whether their presence correlates with right ventricular morphology. BACKGROUND: The presence of coronary arterial fistulas significantly alters the surgical options and prognosis for patients with pulmonary atresia with intact ventricular septum. The lesion can reliably be diagnosed using fetal echocardiography, and further definition of the prognosis is important for counselling parents. METHODS: We examined the hearts of 39 pathological specimens diagnosed during fetal life, 3 of whom died postnatally. Coronary arterial abnormalities were defined as non-connection of the left or right coronary arteries to the aorta, ostial stenosis, marked tortuosity, dilation, thickening or abnormal myocardial branching. Mild tortuosity, or myocardial bridging, were considered normal. We measured the dimensions of the tricuspid valve along with the inlet and outlet portions of the ventricles. Ebstein's malformation, tricuspid valvar dysplasia, and the presence or absence of the infundibulum, were especially noted. We examined also 12 normal hearts as controls. RESULTS: Coronary arterial abnormalities were found in 14/39 (36%). The dimensions of the right ventricle and tricuspid valves, and the gestational ages of the fetuses, were compared for these 14 with the 25 having no abnormalities using independent t-tests. The gestational ages were similar, 21.9 vs 21.1 weeks. The mean dimensions of the tricuspid valve, median z-scores, and right ventricle were smaller, 2.9 vs 7.2 mm; p < 0.002; -4.46 vs 0.23; p < 0.03; and 6.9 vs 13.7 mm; p < 0.002, for those with coronary arterial abnormalities. Ebstein's malformation, or dysplasia of the tricuspid valve, was present in 4 of 14 with, vs 15 of 25 without, coronary arterial abnormalities. A patent infundibulum was noted in 34 of 39 specimens. CONCLUSIONS: Mid-trimester fetuses with pulmonary atresia with intact ventricular septum already exhibit coronary arterial abnormalities, with a prevalence of 36%. The presence of a patent infundibulum confirms that atresia of the pulmonary valve is an acquired process. Coronary arterial abnormalities are seen in 50% of those with hypoplastic right ventricles, but less frequently in the presence of well developed ventricles. This is important information for those involved in counselling parents.     

Transcatheter left ventricular outflow tract stent placement in a low birth weight child with hypoplastic left ventricle,mitral atresia,transposition of the great arteries,ventricular septal defect and severe pulmonary stenosis

A baby boy, the first of triplets born at 33 weeks gestation weighing 1.88 kg, presented with neonatal cyanosis and was diagnosed with mitral atresia, hypoplastic left ventricle, ventricular septal defect, d‐transposition of the great arteries, severe pulmonary stenosis, and hypoplastic branch pulmonary arteries. He was treated with prostaglandin until seven weeks of age. The patent ductus arteriosus was curly Q and not suitable for stent placement. Cardiac catheterization was undertaken and using an antegrade approach, a Multi‐Link Ultra stent was implanted across the left ventricular outflow tract (LVOT) and inflated to 5 mm to improve antegrade pulmonary blood flow. This allowed reasonable pulmonary arterial growth to allow the patient undergo bidirectional Glenn shunt at five months of age. This first report of LVOT stenting in this setting may provide an alternative to placement of a systemic to pulmonary arterial shunt when ductal stenting is not possible. © 2013 Wiley Periodicals, Inc.     

Tricuspid atresia with overriding imperforate tricuspid membrane: an anatomic variant

An anatomical study of 34 specimens presenting with tricuspid atresia, in which particular emphasis was devoted to the atrioventricular junctional area, revealed 5 cases with an imperforate valve. In 1 heart the valve was completely committed to the right ventricle. In the other 4, however, the membrane was related not only to the right ventricle but also to the left ventricle. A hypoplastic right ventricular inlet portion was found in these 4 specimens. In 2 cases the tricuspid membrane overrode an inconspicuous inlet septal defect. In the other 2 hearts, as studied macroscopically, no defect was present underneath the membrane, which was connected to both right and left ventricles. These 4 specimens also had other ventricular septal defects. In classical tricuspid atresia, characterized by absence of the inlet portion of the right ventricle, the inlet septum is absent. In contrast, these 4 hearts did have an hypoplastic inlet septum.     

Double outlet left ventricle with intact ventricular septum

Two cases of double outlet left ventricle with intact ventricular septum are reported. Both patients presented with neonatal cyanosis and signs of right ventricular outflow tract obstruction. Both have hypoplastic right ventricles with suprasystemic pressures, pulmonary to mitral valve continuity and the aorta in left-sided position. These seem to be the second and third cases of the malformation to be described thus far.     

Cross sectional echocardiographic identification of hypoplastic left heart syndrome and differentiation from other causes of right ventricular overload

To identify the echocardiographic features that can be used to distinguish between hypoplastic left heart syndrome and other causes of right ventricular overload in the sick neonate cross sectional echocardiographic studies of 10 neonates with hypoplastic left heart syndrome were analysed and compared with those in 15 neonates with other causes of right ventricular overload and 15 normal controls. Left ventricular and right ventricular cavity dimensions and the shape and size of the mitral valve annulus and aortic root were recorded and presented both as absolute values (mm) and corrected for body surface area (mm/m2). Logistic regression was used to produce a classification rule to estimate the probability of a neonate having hypoplastic left heart syndrome. The diameter of the mitral valve annulus was the single most discriminative variable. There was, however, considerable overlap of all the calculated features between neonates with hypoplastic left heart syndrome and those with other causes of right ventricular overload. The diagnosis of hypoplastic left heart syndrome should not be based on any one single echocardiographic feature but the general appearance of abnormal left heart valves, small cavity dimensions, and the size of the mitral valve annulus.     

Cross sectional echocardiographic identification of hypoplastic left heart syndrome and differentiation from other causes of right ventricular overload.

To identify the echocardiographic features that can be used to distinguish between hypoplastic left heart syndrome and other causes of right ventricular overload in the sick neonate cross sectional echocardiographic studies of 10 neonates with hypoplastic left heart syndrome were analysed and compared with those in 15 neonates with other causes of right ventricular overload and 15 normal controls. Left ventricular and right ventricular cavity dimensions and the shape and size of the mitral valve annulus and aortic root were recorded and presented both as absolute values (mm) and corrected for body surface area (mm/m2). Logistic regression was used to produce a classification rule to estimate the probability of a neonate having hypoplastic left heart syndrome. The diameter of the mitral valve annulus was the single most discriminative variable. There was, however, considerable overlap of all the calculated features between neonates with hypoplastic left heart syndrome and those with other causes of right ventricular overload. The diagnosis of hypoplastic left heart syndrome should not be based on any one single echocardiographic feature but the general appearance of abnormal left heart valves, small cavity dimensions, and the size of the mitral valve annulus.     

Unnatural history of the right ventricle in patients with congenitally malformed hearts

The long-term outcome of patients with congenitally malformed hearts involving abnormal right ventricular morphology and haemodynamics is variable. In most instances, the patients are at risk for right ventricular failure, in part due to morphological differences between the right and left ventricles and their response to chronic volume and pressure overload. In patients after repair of tetralogy of Fallot, and after balloon valvotomy for valvar pulmonary stenosis, pulmonary regurgitation is the most significant risk factor for right ventricular dysfunction. In patients with a dominant right ventricle after Fontan palliation, and in those with systemic right ventricles in association with surgically or congenitally corrected transposition, the right ventricle is not morphologically capable of dealing with chronic exposure to the high afterload of the systemic circulation. In patients with Ebstein's malformation of the tricuspid valve, the degree of atrialisation of the right ventricle determines how well the right ventricle will function as the pump for the pulmonary vascular bed.     

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.     

An infant with hypoplastic left heart syndrome and spinal muscular atrophy

We report an infant with hypoplastic left heart syndrome consisting of mitral valvar atresia, aortic valvar atresia, hypoplasia of the aortic arch and coarctation of the aorta, who demonstrated respiratory failure and global hypotonia, and who was eventually diagnosed with spinal muscular atrophy.     

Heart malformations in trisomy 13 and trisomy 18]

Congenital heart diseases were studied in children diagnosed of trisomy 13 and trisomy 18 in our hospital between January 1973 and July 1990. Twenty patients with trisomy 18 were diagnosed (18 females and two males). All had cardiac malformations. The findings were: ventricular septal defect in 16 cases (80%), valvular anomalies in 12 (63%), patent ductus arteriosus in nine (47%) and atrial septal defect or patent foramen ovale in 7 cases (36%). We found some complex congenital cardiac diseases: one atrioventricular canal, one tetralogy of Fallot, one hypoplastic left ventricle with mitral atresia and double outlet right ventricle, one case of univentricular heart with aortic outlet from a rudimentary cavity, a right ventricular atresia with pulmonary and tricuspid valves atresia. Nine cases of trisomy 13 were diagnosed (seven females and two males). We found: ventricular septal defect in 7 cases (77%), valvular disease in five (100% of the necropsy studies), secundum atrial septal defect in 4 patients (80%) and patent ductus arteriosus in two. Two cases presented hypoplastic left ventricle with aortic arch hypoplasia, one of them had subaortic stenosis and left superior vena cava being connected to the right atrium via coronary sinus; one case showed fibroelastosis. Our results have been similar to the previously reported and confirm the invariably presence of cardiac malformations in these syndromes. These malformations are an important sign of suspicion in fetal ultrasonography.     

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.     

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.     

Aortic atresia. Presentation of 7 cases

The clinical and anatomic findings of 7 patients with aortic atresia were studied. All cases had usual atrial arrangement, atrioventricular and ventriculoarterial concordance. All but one had an intact ventricular septum. All cases presented a hypoplastic left ventricle, and in one, a mitral atresia was found. The clinical diagnosis was made by means of cardiac catheterization and angiocardiography. The presence of a patent ductus arteriosus, the size of the atrial and ventricular septal defects, the diameter of the ascending aorta, pulmonary vascular resistances and right ventricular function are all factors that influence the survival in the patients with aortic atresia.     

Left ventricular dysfunction in the fetus: relation to aortic valve anomalies and endocardial fibroelastosis.

OBJECTIVE--To examine the relation between a characteristic form of left ventricular dysfunction in the fetus and abnormalities of the aortic valve and endocardial fibroelastosis of the left ventricle. DESIGN--A retrospective study to examine the correlation between echocardiographic findings in the fetus and postnatal or necropsy findings. SETTING--Tertiary referral centre for fetal echocardiography. PATIENTS--Thirty fetuses showing a characteristic echocardiographic picture of left ventricular dysfunction. MAIN OUTCOME MEASURES--The relation between the prenatal echocardiographic features and the postnatal and necropsy findings. RESULTS--At presentation the size of the left ventricular cavity was normal or enlarged in all cases. The measurements of the orifice of the aortic root and mitral valve were either normal or small for the gestational age. The echocardiographic diagnosis made at presentation was critical aortic stenosis in all cases. At necropsy or postnatal examination the aortic valve was dysplastic and stenotic in 15 cases and the left ventricle had become hypoplastic in one of these. Aortic atresia was present in seven patients, three of whom had a hypoplastic left ventricle. In six patients the aortic valve was bicuspid although not obstructive. One of these patients had hypoplasia of the aortic arch and one had a hypoplastic left ventricle but in the remaining four patients endocardial fibroelastosis of the left ventricle was the only abnormality found. No follow up information was available in two. Of 26 patients for whom there was postmortem information, 24 had evidence of some degree of endocardial fibroelastosis of the left ventricle. Sequential observations showed that five cases developed into the hypoplastic left heart syndrome. CONCLUSIONS--This type of left ventricular dysfunction in the fetus is the result of an overlap of diseases, including primary left ventricular endocardial fibroelastosis, critical aortic stenosis, and the hypoplastic left heart syndrome.     

Congenitally corrected transposition with pulmonary atresia and intact ventricular septum

We describe a patient with the rare association of the heart in the left chest, congenitally corrected transposition, pulmonary atresia and an intact ventricular septum. There were associated fistulous communications between the morphologically left ventricle and the coronary arteries. Diagnosis was made by echocardiography, and subsequently confirmed by cardiac catheterization.     

Left ventricular dysfunction in the fetus: relation to aortic valve anomalies and endocardial fibroelastosis.

OBJECTIVE--To examine the relation between a characteristic form of left ventricular dysfunction in the fetus and abnormalities of the aortic valve and endocardial fibroelastosis of the left ventricle. DESIGN--A retrospective study to examine the correlation between echocardiographic findings in the fetus and postnatal or necropsy findings. SETTING--Tertiary referral centre for fetal echocardiography. PATIENTS--Thirty fetuses showing a characteristic echocardiographic picture of left ventricular dysfunction. MAIN OUTCOME MEASURES--The relation between the prenatal echocardiographic features and the postnatal and necropsy findings. RESULTS--At presentation the size of the left ventricular cavity was normal or enlarged in all cases. The measurements of the orifice of the aortic root and mitral valve were either normal or small for the gestational age. The echocardiographic diagnosis made at presentation was critical aortic stenosis in all cases. At necropsy or postnatal examination the aortic valve was dysplastic and stenotic in 15 cases and the left ventricle had become hypoplastic in one of these. Aortic atresia was present in seven patients, three of whom had a hypoplastic left ventricle. In six patients the aortic valve was bicuspid although not obstructive. One of these patients had hypoplasia of the aortic arch and one had a hypoplastic left ventricle but in the remaining four patients endocardial fibroelastosis of the left ventricle was the only abnormality found. No follow up information was available in two. Of 26 patients for whom there was postmortem information, 24 had evidence of some degree of endocardial fibroelastosis of the left ventricle. Sequential observations showed that five cases developed into the hypoplastic left heart syndrome. CONCLUSIONS--This type of left ventricular dysfunction in the fetus is the result of an overlap of diseases, including primary left ventricular endocardial fibroelastosis, critical aortic stenosis, and the hypoplastic left heart syndrome.