Atrioventricular discordance without ventriculo-arterial discordance. Apropos of 3 cases

Three cases of atrioventricular without ventriculo-arterial discordance are reported. The first case was a young woman with situs solitus, atrioventricular discordance and ventriculo-arterial concordance, large atrial and small ventricular septal defects. The functional tolerance was relatively good. The second case was an infant girl with dextrocardia by dextroversion and abdominal situs solitus. The child had atrioventricular discordance with ventriculo-arterial concordance and an ostium primum atrial septal defect. Cyanosis was mild and, in addition, complete heart block was diagnosed on the fourth day of life. The functional tolerance was good in this case too and growth was normal. The third case was a young girl with levocardia, atrial situs inversus, and abdominal situs inversus. A double outlet right ventricle was diagnosed at catheterisation with atrioventricular discordance, ventricular septal defect, and severe valvular and infundibular pulmonary stenosis. The first palliative procedure was performed at eight months: a left Blalock-Taussig anastomosis. As cyanosis has recurred a second procedure is being considered, the child now being 5 years old. Different forms of atrioventricular discordance without ventriculo-arterial discordance have been described: atrioventricular discordance with ventriculo-arterial concordance; atrioventricular discordance with double outlet right ventricle; atrioventricular discordance with double outlet left ventricle; atrioventricular discordance with a single vessel issuing from the right or left ventricle. With reference to their personal cases and those described in the literature, the authors describe the anatomy, physiopathology and the clinical consequences of the different forms encountered in their cases. The different surgical techniques for each anatomical form of this condition are discussed.     

An unusual form of the transposition complex. Uncorrected levo-transposition with horizontal ventricular septum: Report of two cases.

A distinctive angiographic appearance is described in two patients who had uncorrected levo-transposition of the great vessels. Although levo-transposition with inversion of the ventricles usually results in physiologically corrected transposition, in these patients the anatomy was arranged in such a way as to result in an uncorrected transposition. The following elements were responsible for this physiological condition: normal atrial situs, inverted ventricles with "criss-cross" atrioventricular flow, levo-transposed great arteries. In addition, the morphological right ventricle was hypoplastic, left sided and superior to the left ventricle and the ventricular septum was horizontal in position. The two ventricles were connected via a large ventricular septal defect. The importance of accurate, detailed, preoperative angiographic demonstration of the anatomic situation is stressed.     

A case of isolated atrioventricular discordance.

A case of isolated atrioventricular discordance in situs solitus is described. The importance of a well defined situs and of the presence of both ventricles in making this diagnosis is underlined and previous published reports reviewed. It is suggested that the haemodynamic concept of isolated atrioventricular discordance cannot be described only by the spatial relation between the ventricles (isolated ventricular inversion), but it should be indicted by the pattern of the connection between various flows, as shown by hearts with a normal relation between the ventricles and crossed atrioventricular connection.     

Unique types of criss-cross heart

Three cases of criss-cross heart which we have observed during last five years are described. All of these cases were diagnosed by angiocardiography and two-dimensional echocardiography, and one of them was verified by autopsy. Two of them are unique among cases reported thus far. Case 1 shows ordinary criss-crossing with supero-inferior ventricle, and case 2, extreme crossing atrioventricular (A-V) valves, in which the right-sided right atrium connects to the left posteriorly positioned right ventricle through the tricuspid valve, and the left-sided left atrium to the right anterior left ventricle via a posteriorly positioned mitral valve. In case 3, the criss-cross appearance is secondary to displacement of the heart by compression caused by a diaphragmatic hernia. Findings in these cases suggest that criss-cross heart is caused not only by primary rotation of the ventricles during cardiac morphogenesis but also by secondary rotation of a formed heart induced by extracardiac compression. The degree of rotation in these cases revealed a wide spectrum from minimal to extreme. In addition, subxiphoid two-dimensional contrast echocardiography is recommended as the only accurate method of non-invasive diagnosis of this condition.     

Crossed atrioventricular connections

Four cases of crossed atrioventricular connections are described. All of them were diagnosed at cardiac catheterization by angiocardiography and one was examined pathologically. Two possessed situs solitus, one with concordant connections and the other with discordant connections; the other had two situs inversus, both of them with concordant connections. Two had double-outlet right ventricle, one had transposition of the great arteries, and the other had normally related and connected great arteries. These cases have been interpreted as representing abnormal rotation of the ventricles following sepatation. A review of 36 cases previously reported on and our own cases, suggests that most patients have concordant atrioventricular connections. There are many types of ventriculo-arterial connections, the most frequent being transposition of the great arteries. There has not been any case reported with persistent truncus arteriosus. On the basis of atrioventriculo-arterial connections, we propose a classification for this malformation. We discuss the importance of the bulboventricular loop in the type of atrioventricular connections, some clinical implications for the diagnosis, and analyze the value of the rules to localize the ventricles by means of the position of the great arteries.     

The angiocardiographic appearance of the endocardial cushion defect in selected transposition and malposition complexes.

Although the angiocardiographic features of the endocardial cushion defect (ECD) have been well described in the patient with two normally related ventricles (D-ventricular loop in situs solitus) and normally related great arteries, little attention has been focused on the angiocardiographic appearance of the ECD in patients with complex cardiovascular disease. Because of recent surgical advances in the treatment of single ventricle and double outlet right ventricle complexes, it has become increasingly important to document the status of the atrioventricular valves in these patients. The angiocardiographic features of the ECD are therefore described in two patients, one with D-loop, single left ventricle and outlet chamber, D-transposition of the great arteries, bilateral conus and pulmonary stenosis and the other with dextrocardia, situs inversus, double outlet right ventricle, common atrioventricular canal and pulmonary stenosis. In both patients, the left ventricular outflow tract, despite aortic-mitral discontinuity, is characterized by elongation, scalloping and serration, and the classic appearance of the "gooseneck" deformity is observed on left ventricular angiography. It thus appears that aortic-mitral continuity and two well-formed, normally related ventricles and great arteries are not invariable necessary to the manifestation of the "gooseneck" deformity in the patient with complex cardiovascular disease and associated endocardial cushion defect.     

Isolated atrial inversion Visceral situs solitus, visceroatrial discordance, discordant ventricular d loop without transposition, dextrocardia: Diagnosis and surgical correction

After cardiac catheterization and angiocardiographic studies an infant with cyanosis from birth was found to have visceral situs solitus, visceroatrial discordance without venoatrial discordance, a discordant ventricular d loop without transposition, and dextrocardia. The circulatory pathway was from the venae cavae to right atrium to left ventricle to aorta, and from the pulmonary veins to left atrium to right ventricle to pulmonary artery. An atrial defect was present allowing some mixing between the pulmonary and systemic circulations, but this appeared inadequate and the defect was enlarged surgically. Subsequently, a corrective operation using an atrial baffle to direct the pulmonary venous return to the left ventricle and the systemic venous return to the right ventricle was successfully undertaken.     

Heart with criss-cross ventricles associated with an obstruction of the ejection pathway of the left ventricle and a mitral anomaly

A case of criss-cross heart with situs inversus associated with subvalvular aortic stenosis and mitral regurgitation in a 9 year old boy is reported. Surgical correction of the valvular abnormalities gave an excellent clinical and haemodynamic result. A review of the literature shows that this abnormality of rotation of the ventricles coexists with a concordant atrioventricular connection in 70 % cases; the ventriculoarterial connection is only discordant in 12 % cases. The right ventricle is always situated above the left ventricle. The most common associated lesions are usually accessible to surgery; ventricular septal defect (98 % cases); stenosis or atresia of the pulmonary artery (70% cases). However, right ventricular hypoplasia is also common (65 % cases). Six patients underwent surgical correction of the associated lesions with 4 successes and 2 deaths. Surgery is possible in these complex cardiac malformations with good results providing a precise preoperative anatomical diagnosis is made.     

The spectrum of atrioventricular discordance. A clinical study.

The clinical, investigative, and surgical findings were reviewed in 47 patients with atrioventricular discordance who presented to the Brompton Hospital between January 1962 and June 1981. Although the unifying feature was the atria connecting to morphologically inappropriate ventricles, the hearts differed widely in other respects. In most cases there was the usual visceral and atrial arrangement, but six had a mirror image arrangement of the atria and viscera. Among those patients with usual atrial arrangement (solitus) the aorta was not always anterior and left sided, and ventricular "inversion" was not invariable. Only 35 of the 47 patients also had a discordant ventriculoarterial connexion, the majority of the remainder having a double outlet right ventricle. The specific diagnosis of atrioventricular discordance depended on echocardiographic and angiographic examination. The other investigations did not distinguish between different ventriculoarterial connexions and were not specific even for the presence of atrioventricular discordance. For those patients with the usual atrial arrangement the anticipated right heart border was present in only just over one third, and the reversal of Q wave progression in the precordial leads of the standard electrocardiogram was found in under a half. Many patients with atrioventricular discordance progressed normally to adult life. In 20 cases no surgery was performed. The results of total correction showed a mortality of 25% (three cases), including two deaths after a modified Fontan procedure for exceedingly complex associated lesions. The results of surgery in the survivors were excellent, and awareness of the disposition of the atrioventricular conduction tissue made it possible to avoid atrioventricular dissociation.     

Atrioventricular discordance in situs inversus.

We retrospectively analysed the records of 23 patients with atrioventricular discordance in situs inversus and compared them with 121 cases of atrioventricular discordance in situs solitus seen during preceding four years. One hundred and two (70.8%) patients were male. The mean age was 9.3 +/- 10.1 years (range 1 day-48 years). Overall, a ventricular septal defect with pulmonic stenosis (Fallot's physiology) was seen in 76 (56.7%) cases, ventricular septal defect without pulmonic stenosis in 26 (18.1%) cases, atrioventricular valve regurgitation in 25 (17.3%) cases and complete heart block in 13 (9%) cases. Double outlet right ventricle and Fallot's physiology were significantly more common (74.0% vs 32.3% and 91.3% vs 45.0%, respectively; p < 0.005), whereas atrioventricular valve regurgitation and complete heart block were less common (4.3% vs 19.8% and 0% vs 10.7%, respectively; p < 0.05) in patients with situs inversus and atrioventricular discordance as compared to patients with situs solitus. These differences may influence the natural history and treatment options selected for patients with atrioventricular discordance.     

The spectrum of atrioventricular discordance. A clinical study

The clinical, investigative, and surgical findings were reviewed in 47 patients with atrioventricular discordance who presented to the Brompton Hospital between January 1962 and June 1981. Although the unifying feature was the atria connecting to morphologically inappropriate ventricles, the hearts differed widely in other respects. In most cases there was the usual visceral and atrial arrangement, but six had a mirror image arrangement of the atria and viscera. Among those patients with usual atrial arrangement (solitus) the aorta was not always anterior and left sided, and ventricular "inversion" was not invariable. Only 35 of the 47 patients also had a discordant ventriculoarterial connexion, the majority of the remainder having a double outlet right ventricle. The specific diagnosis of atrioventricular discordance depended on echocardiographic and angiographic examination. The other investigations did not distinguish between different ventriculoarterial connexions and were not specific even for the presence of atrioventricular discordance. For those patients with the usual atrial arrangement the anticipated right heart border was present in only just over one third, and the reversal of Q wave progression in the precordial leads of the standard electrocardiogram was found in under a half. Many patients with atrioventricular discordance progressed normally to adult life. In 20 cases no surgery was performed. The results of total correction showed a mortality of 25% (three cases), including two deaths after a modified Fontan procedure for exceedingly complex associated lesions. The results of surgery in the survivors were excellent, and awareness of the disposition of the atrioventricular conduction tissue made it possible to avoid atrioventricular dissociation.     

The cardiac conduction system in situs ambiguus.

The cardiac specialized conduction tissue was studied by serial sectioning in 13 cases of situs ambiguus. In four cases of right isomerism, we found paired sinus nodes in relation to a crista terminalis, and in each case a sling of conduction tissue between two atrioventricular nodes was present regardless of the ventricular morphology or cardiac position. In the cases with left isomerism, the sinus node was hypoplastic and abnormally located. We saw two types of atrioventricular conduction systems. In the three cases in which the morphologically right ventricle lay to the right of the morphologically left ventricle (presumed d-loop), a single atrioventricular bundle arose from a normally located atrioventricular node. In the five cases in which the morphologically right ventricle lay to the left of the morphologically left ventricle (presumed l-loop) and in the one case with a univentricular heart, paired atrioventricular nodes were present, linked or potentially linked by a sling of conduction tissue.     

Double outlet right ventricle with atrioventricular discordance. Report on cases having situs solitus, dextrocardia, pulmonary stenosis and levomalposition of the aorta

We describe six patients with situs solitus of viscera and atria, dextrocardia, atrioventricular discordance, ventricular septal defect, double outlet from the morphological right ventricle, pulmonic stenosis and levomalposition of the aorta. Four patients were male and two female; their age ranged from 3.5 to 31 years (mean 13.8 years). All had various degrees of disability, and presented with cyanosis, clubbing and high hematocrit levels. One patient had an atrio-ventricular block that varied from first to third degree; another patient showed intermittent junctional rhythm. At angiography the ventricular septum appeared to be almost perpendicular to the frontal plane in most cases, so that the anteroposterior projection resulted in a true axial view. One overriding left atrioventricular valve and one straddling right atrio-ventricular valve were demonstrated; no significant incompetence of either valve was observed. The ventricular septal defect was always single and related to the subpulmonary outflow. Pulmonic stenosis was valvular in every patient; an additional infundibular obstruction was present in one case. In two cases an additional stenosis was discovered at the supravalvular level. The left pulmonary branch was stenotic in one case; it was hypoplastic, with controlateral dilatation, in two cases; both pulmonary arteries were dilated in one case. The aorta was always to the left of the pulmonary artery, either anterior or side by side. Three patients were operated on in different Institutions: one had a pulmonic valvotomy at the age of six years; one, aged twenty, had a right Blalock-Taussig shunt; the third, with overriding left atrioventricular valve, underwent a modified Fontan operation at the age of thirty years with success.(ABSTRACT TRUNCATED AT 250 WORDS)     

Double outlet right ventricle with discordant atrioventricular connection. Clinical study

The clinical and anatomic findings were reviewed in 17 patients with double-outlet right ventricle and atrioventricular discordance. Ten cases had atrial situs solitus, seven with right-sided heart three with left-sided heart. Seven cases had atrial situs inversus, five with left-sided heart and two with right-sided heart. All cases presented ventricular septal defect, 13 subvalvar pulmonary stenosis, two tricuspid regurgitation and two complete atrioventricular block. The spatial relationship between the arterial valves are variable. Most cases in atrial situs solitus had a left-sided and anterior aorta and all patients in atrial situs inversus had a right-sided and anterior aorta. In this study we compared the anomalies found in our cases with double outlet right ventricle with those in 58 patients with corrected transposition. Absolute, relative and attributable risks were calculated for the presence of subvalvular pulmonary stenosis, ventricular septal defect, tricuspid regurgitation and atrioventricular block for each the two groups. We concluded that patients with double-outlet right ventricle are more prone to present ventricular septal defect and subvalvar pulmonary stenosis, while those with corrected transposition have a greater likelihood of presenting with tricuspid regurgitation and atrioventricular block. There is no typical clinical picture for the malformations. Symptoms depend upon the associated anomalies. The final diagnosis is best achieved by the echocardiographic and angiocardiographic studies, but electrocardiogram and chest radiograph may suggest the presence of a discordant atrioventricular connection.     

Right ventricular diastolic overloading in left bundle-branch block

The combination of left bundle-branch block with right ventricular hypertrophy is said to be exceptional. Faced with this possibility, many authors consider a diagnosis of right ventricular hypertrophy as impossible. The two cases reported were found in a total of approximately 10,000 vectorcardiograms. Starting in 1950, Laham drew attention to the special morphology of precordial left bundle-branch block when there is right ventricular hypertrophy. In 1971, Chou and Helm suggested vectorcardiographic criteria for right ventricular hypertrophy in the case of left bundle-branch block--right posterior shift of the QRS loop and clockwise rotation on the horizontal plane. These criteria are satisfied in the first case, i.e. partial atrioventricular canal, but not in the second, i.e. ostium secundum defect. In both cases, the appearance of the left bundle-branch block is very atypical.     

Cardiac auscultation: a re-emphasis. Clues from physical maneuvers and pharmacologic agents.

Seven patients with corrected transposition were studied by qualitative radionuclide angiocardiography. In four patients with situs solitus with apex on the left, the pulmonary artery was in a medial and posterior position, to the right of the aorta, with its root attached to the morphological left ventricle positioned on the right. The aorta arose from the ventricle placed on the left and had an anterior position. The ventricle located on the right has a triangular shape. In the case of situs solitus with dextroversion, the pulmonary artery was to the right of the aorta and had a right-to-left direction. The ventricle placed on the right was ovoid. In one single case of situs inversus with levoversion, the pulmonary artery was on the left, emerging from the morphological left ventricle placed on the left, and was ovoid in shape, while the aorta was on the right arising from the morphological right ventricle. In one case of situs inversus with dextrocardia, atrioventricular relationships were the same as in levoversion but the apex was on the right and the morphological left ventricle was triangular. Qualitative radionuclide angiocardiography is a simple and non-invasive method for obtaining morphological data for the precise diagnosis of corrected transposition.     

The clinical features and diagnosis of a discordant atrioventricular connexion

Seventy-three patients were studied with a discordant atrioventricular connexion (ages 3 months to 46 years). In 58 the diagnosis was proved by angiography and in the other 15 at necropsy. Forty-eight had usual atrial arrangement and 25 mirror-image atria. Fifty-two patients had ventriculo-arterial discordance, 13 double outlet right ventricle, 4 ventriculoarterial concordance, 3 single outlet of the heart and 1 double outlet left ventricle. Nine with ventriculoarterial discordance had no other associated defects. The spatial relationship of the ventricles was variable, but in usual atrial arrangement the morphologically left ventricle tended to be on the right, and in mirror-image arrangement to the left of the morphologically right ventricle. The spatial relationship between the arterial valves was also variable, but in ventriculoarterial discordance and double outlet right ventricle the aortic valve was anterior and either to the right or left of the pulmonary valve in all but 3 cases. There is no typical clinical picture for these malformations. Symptoms depend upon the associated anomalies or the presence of atrioventricular dissociation. The diagnosis of a discordant atrioventricular connexion is best achieved by the echocardiographic and haemodynamic studies, but the electrocardiogram, chest radiograph and nuclear medicine studies may suggest its presence. Most patients are asymptomatic and progress normally to adult life. Only the symptomatic patients require surgical correction. Postoperative follow-up in the survivors is excellent, only 2 of 14 patients dying after surgery.     

Concordant Atrioventricular Connection to L-Looped Ventricles with the Left Ventricle on Top of the Right Ventricle in Situs Solitus: A Case Report with 3D Modelling and Printing

We report the case of a rare complex cardiac anomaly involving situs solitus, concordant atrioventricular connection with left-hand ventricular topology, and L-looped ventricles. The ventricles had a superior-inferior relationship with an inferiorly located right ventricle, which had a double outlet with far posteriorly located great arteries. The left atrium was elongated, with juxta-positioned atrial appendages on the right side. The 3D-printed model using a computed tomography scan taken on the fourth day of birth demonstrated the anatomy clearly and helped us decide on the surgical management.     

Morphology and classification of complete atrioventricular defects

Anatomical studies were made on 70 necropsied hearts with atrioventricular defects from patients with situs solitus and atrioventricular concordance, all having a common atrioventricular orifice. The arterial connections were concordant in 68 and were double outlet right ventricle in two; cases with arterial discordance (transposition) or single outlet of the heart were excluded. It proved possible to subdivide the hearts, depending on the morphology of the valve leaflets. Five leaflets were distinguished by the commissural pattern and their insertion to major papillary muscles. They were a posterior bridging leaflet, right and left lateral leaflets, and right and left anterior leaflets. Subdivision was made on the basis of the disposition of the anterior leaflets. In six hearts the left anterior leaflet was committed to the left ventricle and the right anterior leaflet to the right ventricle, the commissure between them being on the crest of the ventricular septum. In 39 hearts there was minimal bridging of the left anterior leaflet so that it extended between the anterior papillary muscle of the left ventricle and the medial papillary complex of the right ventricle. In eight hearts the right margin of the left anterior leaflet was attached to an apical papillary muscle, while in 17 hearts it was attached to the anterolateral papillary muscle of the right ventricle. As the bridging of the left anterior leaflet increased, so the size of the right anterior leaflet decreased, but in all hearts both leaflets were identified. These findings were compared with previous classifications of complete atrioventricular defects.