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.     

Morphologic characteristics of aortic atresia: implications for fetal hemodynamics

We studied hearts with aortic atresia to determine the relationship between cardiac morphology and fetal cardiac blood flow. We compared measurements of aortic, pulmonary, and tricuspid valve circumference and right ventricular wall thickness among 37 hearts with aortic atresia and mitral hypoplasia, 14 hearts with aortic atresia together with mitral atresia and 24 normal hearts. Right ventricular free wall thickness and tricuspid and pulmonary valve annular circumferences were greater and aortic circumferences were smaller in hearts with aortic atresia than in normal hearts (P less than 0.05). Between the subgroups of aortic atresia, the aortic circumference was 5 +/- 1 mm in those with mitral atresia compared to 7 +/- 2 mm in association with mitral hypoplasia (P less than 0.05). The morphologic differences between the subgroups of aortic atresia are consistent with differences in fetal blood flow. Left heart blood flow was likely to be greater during development in those hearts with aortic atresia and mitral hypoplasia than in those with the combination of aortic and mitral atresia.     

Hypoplastic left heart syndrome: experience with palliative surgery

Aortic atresia is a form of hypoplastic left heart syndrome always complicated by associated severe hypoplasia of the ascending aorta and various degrees of mitral valve and left ventricular hypoplasia. At present it is a universally fatal lesion in early infancy. This is a report of a new palliative procedure for hypoplastic left heart syndrome that has resul;ed in early ongoing survival of two infants with aortic atresia. On the basis of experience with a third patient, an operation for future physiologic correction is proposed.     

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.     

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.     

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.     

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.     

Atresia of left atrioventricular orifice. Anatomical investigation in 62 cases.

Sixty-two hearts without a patent exit from the left atrium to the ventricular mass have been studied. All had situs solitus and laevocardia. The material consisted of 32 cases with coexistent aortic atresia and 30 cases with patent aortic root. Five hearts with aortic atresia were biventricular with atrioventricular concordance and imperforate left atrioventricular valves, and 27 hearts were univentricular of right ventricular type, with absent left atrioventricular connection. The anatomy of this group was uniform, with extreme hypoplasia of all the left cardiac segments. Among the cases with patent aortic root, five were biventricular, with atrioventricular concordance and imperforate left atrioventricular valves, and 24 had absent left atrioventricular connection, 15 with univentricular heart of right ventricular type and nine with univentricular heart of left ventricular type. The final heart had double inlet univentricular of left ventricular type with an imperforate left atrioventricular valve. In this second group the aorta was larger in cases with discordant ventriculoarterial connection or in those with double outlet from the main ventricular chamber. A normal sized aorta without aortic arch obstruction was observed in nine instances. These are of great interest in terms of surgical anatomy since definitive palliation may be feasible.     

A case of PAGOD syndrome with hypoplastic left heart syndrome

PAGOD syndrome is an extremely rare congenital malformation complex involving multiple organs. These include pulmonary artery and lung hypoplasia, diaphragm defects, omphalocele, sex reversal or ambiguous genitalia, and complex cardiac defects. Eight cases have been reported to date. We report a case of PAGOD syndrome that is manifested by right diaphragm eventration, horseshoe lung with right lung hypoplasia, hypoplastic left heart syndrome (mitral atresia, aortic atresia), scimitar syndrome, agonadism with ambiguous genitalia. A karyotype revealed normal 46-XY. This patient received a modified Norwood procedure for hypoplastic left heart syndrome as an initial palliation and bidirectional cavopulmonary anastomosis as a second stage of operation. The postoperative courses were uneventful. This patient is waiting for Fontan operation.     

Experimental production of hypoplastic left heart syndrome in the chick embryo

The hypothesis is examined that hemodynamic alterations at the site of the primordial mitral valve may induce malformations that simulate the clinical findings of hypoplastic left heart syndrome. Surgical placement of a nylon device, approximately 90 μ in diameter, into the region of the left atrioventricular (A-V) canal was accomplished in 192 embryos (Hamburger-Hamilton stages 23 to 25). Thirty-nine pairs of experimental and control embryos survived more than 12 days. Twenty-six experimental embryos exhibited various malformations: hypoplastic left atrium and ventricle, mitral valvular atresia, aortic valvular stenosis and tubular hypoplasia of the aorta and brachlocephalic vessels. These findings reemphasize the probable morphogenetic role of blood flow pathways. The findings further implicate involvement of the left A-V canal as well as premature closing of foramen ovale and aortic valvular abnormalities in the 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.     

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.     

Hypoplastic left heart syndrome: report of a unique survivor

A remarkable patient is described, a child who has survived until the age of 7 years with hypoplastic left heart syndrome (mitral and aortic atresia) without surgical intervention. The child has led an active, normal life and, aside from minimal cyanosis, has remained asymptomatic. The unique clinical course for this patient is the result of a number of favorable hemodynamic factors that have not been previously reported in an individual patient with hypoplastic left heart syndrome and intact ventricular septum widely patent ductus arteriosus, adequate retrograde coronary flow, unrestricted pulmonary venous return, and absence of significant vascular obstructive disease. This documentation of long-term survival in a child without surgical treatment for mitral and aortic atresia suggests that successful early palliative treatment for infants with this syndrome could also result in a favorable prognosis.     

Comparison of M mode echocardiography and pathologic findings in the hypoplastic left heart syndrome

The M mode echocardiograms and pathologic specimens from 18 infants with the hypoplastic left heart syndrome were compared to determine the accuracy with which the echocardiogram reflects the state of the mitral valve, left ventricle and aortic valve, and its limitations in establishing this diagnosis. Mitral valve echoes were recorded in 7 of the 11 cases with an anatomic mitral valve orifice diameter greater than 3 mm. Ventricular septal echoes were found only in the seven cases in which the mitral valve was recorded. Differences between echocardiographic and anatomic left ventricular internal dimensions were not statistically significant in this small group. When aortic valve echoes were recorded, this valve was always patent in the anatomic specimen. The aortic valve was atretic in 9 of the 11 cases in which no aortic valve echoes were present. The echocardiographic and anatomic aortic root dimensions had a statistically significant correlation (p < 0.05), but there was considerable scatter in the data.None of the 18 infants met all of the previously proposed criteria for the echocardiographic diagnosis of hypoplastic left heart syndrome. An echocardiographic left ventricular dimension of 10 mm or greater was present in five cases (28 percent), and an aortic root dimension of 10 mm or greater in six (33 percent). The most reliable echocardiographic finding was excursion of 5 mm or less of the anterior leaflet of the mitral valve or inability to detect the mitral valve. Noninvasive findings are not always sufficient to establish the diagnosis of hypoplastic left heart syndrome, and further studies may be necessary in some patients.     

Successful transcatheter coil embolization of coronary artery to left ventricular fistula associated with absent pulmonary valve with tricuspid atresia in early infancy.

Transcatheter coil embolization for coronary artery to left ventricular fistula was successfully performed in a neonate. At 30 weeks' gestation, fetal echocardiography showed a hypoplastic right ventricle with intact ventricular septum, absent pulmonary valve, tricuspid atresia, and marked distension of the right coronary artery. After birth, the neonate had congestive heart failure and the electrocardiogram showed myocardial ischemic changes in the left ventricular area. Aortography showed a dilated right coronary artery arising from the ascending aorta and draining into the left ventricle. Transcatheter coil embolization was carried out on the 9th day after birth. Since the procedure, no myocardial ischemic changes have been detected. Transcatheter coil embolization is a useful therapy for coronary artery fistula associated with myocardial ischemia.     

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.     

Aortic valve atresia with a normally developed left ventricle.

Aortic valve atresia is usually associated with hypoplasia of the left ventricle and mitral valve. We report a patient presenting aortic atresia with ventricular septal defect and a normally sized left ventricle. The electrocardiogram showed left axis deviation and left ventricular hypertrophy. The ventricular septal defect probably favored a normal growth of the left ventricle, allowing it to unload with systole.     

Noonan's syndrome associated with hypoplastic left heart

A case of a week old female baby, admitted because of apathy, hypothermia, dyspnea, jaundice and cyanosis is described. She had the characteristic phenotype of Turner's syndrome with normal karyotype. Signs of severe heart failure were present. Therapy with diuretics, digoxin, dopamine and mechanical ventilation were unsuccessful, and the patient died several hours after her admission. The anatomopathological examination revealed the presence of hypoplastic left heart syndrome with mitral atresia and aortic atresia, atrial septal defect, double outlet right ventricle, and a patent ductus arteriosus.     

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.