Double outlet right ventricle; a partial transposition complex

Double Outlet of Both Ventricles With an Unusual Relationship of the Great Arteries

Double outlet both ventricles (DOBV) is a rare form of ventriculo-arterial connection wherein the outlet septum is perpendicular to the crest of the apical muscular ventricular septum, thus committing both arterial roots equally to both ventricles. The anomaly has been described in very few reports, with clinical reports being even rarer. We report perhaps the first case of DOBV in which the relationship of the arterial roots themselves is discordant relative to the ventricular topology.

Multicentre study on late outcomes of biventricular repair of double outlet right ventricle

OBJECTIVES

The goal of this retrospective multicentre study was to present late surgical outcomes of the treatment of children with double outlet right ventricle (DORV) coming from emerging countries.

METHODS

The Mécénat Chirurgie Cardiaque brings to France for surgery selected children with simple and complex congenital diseases, including DORV. The patients are operated on in 9 hospitals that specialize in paediatric cardiac surgery. Data are collected from the Mécénat Chirurgie Cardiaque comprehensive database, with a strict postoperative follow-up. The patients included only those who had biventricular repair of DORV with 2 viable ventricles. According to the classification of the Eleventh Revision of the International Classification of Diseases, DORV was defined as a congenital cardiovascular malformation in which both great arteries arise entirely or predominantly from the morphologically right ventricle.

RESULTS

From January 1996 to January 2022, a total of 81 consecutive DORV biventricular repair operations were performed. There were 6 subtypes of DORV divided into 2 groups: DORV-committed ventricular septal defect (VSD): DORV-VSD (n = 25), DORV-Fallot (n = 34), DORV-transposition of the great arteries (n = 5); and DORV-non-committed (nc) VSD: DORV-ncVSD-no pulmonary stenosis (PS) (n = 7), DORV-ncVSD-PS (n = 5) and DORV-atrioventricular septal defect (AVSD)-PS (n = 5). Four Fontan patients were excluded. Three patients were lost to follow-up (3.4%). The overall perioperative mortality was 7.4% ± 2.6%, 6/81 (95% confidence interval: 2.8%-15.4%) ranging from 0% in DORV-AVSD-PS to 14% for DORV-ncVSD-no PS. The overall 10-year survival was 86%. The early mortality of DORV-ncVSD at 5.9% ± 2.4% (1/17) was similar to that of DORV-committed VSD at 7.8% ± 2.7% (5/64) (P = 0.79). There was a trend towards an optimal outcome for the arterial switch operation and the DORV-AVSD-PS repair. VSD enlargement was significantly more frequent in DORV-ncVSD at 42% (5/12) (P = 0.001). There were low numbers in the complex groups. The number of Fontan cases was noticeably low. The aorta located entirely on the right ventricle represents the fundamental anomaly and the surgical challenge of DORV.

CONCLUSIONS

Overall survival at 10 years was 86%. This study shows a trend towards satisfactory early and late outcomes in BVR of simple DORV with committed VSD, compared to complex DORV with ncVSD.

Double outlet right ventricle

This review article addresses the history, morphology, anatomy, medical management, and different surgical options for patients with double outlet right ventricle.

Double outlet ventricles: review of anatomic and imaging characteristics

Hearts with double outlet ventricles and concordant atrioventricular connections account for about 1%–3% of all cases of congenital heart disease. We review hearts with two ventricles and concordant atrioventricular connections with double outlet right ventricle (DORV), double outlet left ventricle (DOLV) and double outlet both ventricles (DOBV) from the morphological and clinical imaging perspectives. These hearts are a heterogeneous group of congenital cardiac malformations with a wide range of pathophysiologies that require an individualised surgical approach based on a precise understanding of the complex cardiovascular anatomy. Owing to their differing temporal, spatial and contrast resolutions, we propose that multimodality imaging provides optimal characterisation of various intracardiac morphological features of double outlet hearts. This approach aids clinical diagnosis for optimising treatment options across these malformations.

A 'holistic' sonographic view on congenital heart disease - How automatic reconstruction using fetal intelligent navigation echocardiography (FINE) eases the unveiling of abnormal cardiac anatomy part I: Right heart anomalies

Attempting a comprehensive examination of the fetal heart remains challenging for unexperienced operators as it emphasizes the acquisition and documentation of sequential cross-sectional and sagittal views and inevitably results in diminished detection rates of fetuses affected by congenital heart disease. The introduction of four-dimensional spatio-temporal image correlation (4D STIC) technology facilitated a volumetric approach for thorough cardiac anatomic evaluation by the acquisition of cardiac 4D datasets. By analyzing and re-arranging of numerous frames according to their temporal event within the heart cycle, STIC allows visualization of cardiac structures as an endless cine loop sequence of a complete single cardiac cycle in motion. However, post-analysis with manipulation and repeated slicing of the volume usually requires experience and in-depth anatomic knowledge, which limits the widespread application of this advanced technique in clinical care and unfortunately leads to the underestimation of its diagnostic value to date. Fetal intelligent navigation echocardiography (FINE), a novel method that automatically generates and displays nine standard fetal echocardiographic views in normal hearts, has shown to be able to overcome these limitations. Very recent data on the detection of congenital heart defects (CHDs) using the FINE method revealed a high sensitivity and specificity of 98% and 93%, respectively. In this two-part manuscript, we focused on the performance of FINE in delineating abnormal anatomy of typical right and left heart lesions and thereby emphasized the educational potential of this technology for more than just teaching purposes. We further discussed recent findings in a pathophysiological and/or functional context.

Double outlet of both ventricles: morphological, echocardiographic and surgical considerations

OBJECTIVES

To describe the morphology, echocardiographic features and surgical management of the entity appropriately described as 'double outlet of both ventricles'.

METHODS

Seven patients (5 males, age 0.5-7.5 months) were diagnosed to have a unique form of subarterial ventricular septal defect (VSD) and ventriculo-arterial connection, where a muscular outlet septum straddled the crest of the ventricular septum in a cruciate manner, such that both great arteries were equally committed to both ventricles. Diagnosis was established by echocardiography, with 6 patients submitted to surgical repair by means of intracardiac routing of the left ventricle to the aorta using 2 patches.

RESULTS

Surgical repair was successful in all 6 patients in whom it was attempted. In addition, 1 patient underwent concomitant repair of aortic coarctation, and 2 had closure of multiple VSDs. We lost 1 patient to follow-up after diagnosis. Follow-up with a range from 3 months to 8 years in the remaining patients revealed all to be clinically well with satisfactory growth of both outflow tracts.

CONCLUSIONS

We describe a series of patients with the ventriculo-arterial connection best described as 'double outlet of both ventricles'. Diagnosis is readily established by echocardiography. Good early and midterm results can be expected subsequent to surgical repair using 2 patches for interventricular septation.

Prenatal diagnosis of double-outlet right ventricle with tricuspid valve atresia, anomalous pulmonary vein connection, persistent left superior vena cava, and right atrial isomerism

Double-outlet right ventricle is a conotruncal cardiac disease in which both the aorta and the pulmonary artery predominantly or completely originate from the right ventricle. Here, we report a complex variant double-outlet right ventricle detected in utero and identified on the basis of a segmental approach.

Prenatal diagnosis, associated findings and postnatal outcome of fetuses with double outlet right ventricle (DORV) in a single center

Objective To assess the spectrum of associated anomalies, the intrauterine course, postnatal outcome and management of fetuses with double outlet right ventricle (DORV). Methods All cases of DORV diagnosed prenatally over a period of 8 years were retrospectively collected in a single tertiary referral center. All additional prenatal findings were assessed and correlated with the outcome. The accuracy of prenatal diagnosis was assessed. Results Forty-six cases of DORV were diagnosed prenatally. The mean gestational age at first diagnosis was 21+4 weeks (range, 13-37). A correct prenatal diagnosis of DORV was made in 96.3% of the cases. If the relation of the great arteries, the position of the ventricular septal defect (VSD) and additional cardiac anomalies are taken into account, the prenatal diagnosis was correct in 92.6% of the cases. One case was postnatally classified as transposition of the great arteries with subpulmonary VSD and was excluded from further analysis. A total of 41 (91.1%) fetuses with DORV had major additional cardiac anomalies, 30 (66.7%) had extracardiac anomalies and 13 (28.9%) had chromosomal or syndromal anomalies. Due to their complex additional anomalies, five (11.1%) of our 45 fetuses had multiple malformations and were highly suspicious for non-chromosomal genetic syndromes, although molecular diagnosis could not be provided. Disorders of laterality occurred in 10 (22.2%) fetuses. There were 17 terminations of pregnancy (37.8%), two (4.4%) intrauterine and seven (15.6%) postnatal deaths. Nineteen of 22 (86.4%) live-born children with an intention to treat were alive at last follow-up. The mean follow-up among survivors was 32 months (range, 2-72). Of 21 children who had already undergone postnatal surgery, eight (38.1%) achieved biventricular repair and 13 (61.9%) received univentricular palliation. One recently born child is still waiting for surgery. All children predicted prenatally to need a single ventricle palliation, and all children predicted to achieve biventricular repair, ultimately received the predicted type of surgery. After surgery, 14 of 18 (77.8%) children were healthy without any impairment. Conclusion DORV is a rare and often complex cardiac anomaly that can be diagnosed prenatally with high precision. DORV is frequently associated with major additional anomalies, leading to a high intrauterine and postnatal loss rate due to terminations or declined postnatal therapy. Without additional anomalies, the prognosis is good, although approximately 60% of children will have single ventricle palliation.

How should we diagnose and differentiate hearts with double-outlet right ventricle?

Many, if not most, of the controversies regarding the description of the congenitally malformed heart have been resolved over the turn of the 20th century. A group of lesions that remains contentious is the situation in which both arterial trunks, in their greater part, are supported by the morphologically right ventricle. It was considered, for many years, that presence of bilateral infundibulums, or conuses, was a necessity for such a diagnosis. It has now been appreciated that this suggestion founders on many counts. In the first instance, such bilateral infundibulums are to be found in patients with other ventriculo-arterial connections, including the otherwise normal heart. In the second instance, it is clear that such an approach abrogates the important principle now known as the morphological method. This states that entities should be defined in terms of their intrinsic morphology and not on the basis of other variable features. It is now also clear that, when assessed simply on the basis of the ventricular origin of the arterial trunks, a significant number of patients fulfil the criteria for so-called "200%" origin of the trunks from the right ventricle when there is fibrous continuity between the leaflets of the atrioventricular and arterial valves. In this review, we show how attention to the morphology of the channel between the ventricles now provides the key to accurately diagnose the ventriculo-arterial connection in patients with suspected double-outlet right ventricle. This is because, when both arterial trunks arise exclusively or predominantly from the morphologically right ventricle, the outlet septum, of necessity, is itself a right ventricular structure. The channel between the ventricles, therefore, is roofed by the inner heart curvature, whether that structure is fibrous or muscular. Our observations then confirm that it is the attachment of the outlet septum, which itself can be muscular or fibrous, which determines the commitment of the interventricular communication to the subarterial outlets. The interventricular communication itself, when directly committed to the ventricular outlets, opens between the limbs of the septomarginal trabeculation or septal band. The defect is subaortic when the outlet septum is attached to the cranial limb of the trabeculation, subpulmonary when attached to the caudal limb, and doubly committed when attached to the inner heart curvature in the roof of the defect. Non-committed defects are no longer positioned within the limbs of the septomarginal trabeculation. Although readily demonstrable by a skilled echocardiographer, we show how these anatomical features are more easily demonstrated with added accuracy when using CT data sets.

Perioperative Management of DORV

The diagnosis of double-outlet right ventricle (DORV) characterizes a complex heterogeneous group of congenital cardiac malformations for which multiple classification schemes have been used. A clear understanding of the anatomy is critical to understanding the physiologic consequences of the specific type of DORV. Perioperative considerations include the medical management of the patient during the preoperative period, anesthetic and surgical management, and postoperative care. Both anesthetic and surgical management strategies are very different depending on the type of DORV. Key principles for anesthetic management include balancing the systemic and pulmonary circulations, optimizing systemic cardiac output, and closely monitoring for impaired oxygen delivery to the tissues. Depending on the specific anatomy the patient is usually placed on a 1- or 2-ventricle pathway, and initial palliation may involve placement of a systemic arterial to pulmonary artery shunt or pulmonary artery banding. In some cases the child may undergo a complete repair during the first few months of life. Surgical outcomes, both short and long-term, are dependent on the type of DORV and surgical procedure done. These patients require long-term follow up and may present for surgical or catheter-based interventions as adults.

Transcatheter aortic valve implantation in surgically repaired double outlet right ventricle

A 52-year-old male patient, with a medical history of surgically repaired double outlet right ventricle presented with severe aortic stenosis (AS) and hepatitis C with cirrhosis, presented with New York Heart Association Class IV heart failure. During evaluation for a liver transplant, he was deemed a poor surgical candidate due to his aortic valve disease and cirrhosis with model for end-stage liver disease score of 14. Transthoracic echocardiogram showed severe AS with a mean gradient of 62 mm Hg and calculated aortic valve area of 0.74 cm(2) with a normal ejection fraction of 65%. The patient underwent transfemoral implantation of a 23-mm Edwards Sapien commercial heart valve with significant mean gradient reduction across the aortic valve from 62 to 13 mm Hg. The patient was observed in the coronary care unit and discharged home 2 days postprocedure with his clinical symptoms greatly improved.

Coronary artery embryogenesis in cardiac defects induced by retinoic acid in mice

BACKGROUND

Although normal coronary artery embryogenesis is well described in the literature, little is known about the development of coronary vessels in abnormal hearts.

METHODS

We used an animal model of retinoic acid (RA)-evoked outflow tract malformations (e.g., double outlet right ventricle [DORV], transposition of the great arteries [TGA], and common truncus arteriosus [CTA]) to study the embryogenesis of coronary arteries using endothelial cell markers (anti-PECAM-1 antibodies and Griffonia simplicifolia I (GSI) lectin). These markers were applied to serial sections of staged mouse hearts to demonstrate the location of coronary artery primordia.

RESULTS

In malformations with a dextropositioned aorta, the shape of the peritruncal plexus, from which the coronary arteries develop, differed from that of control hearts. This difference in the shape of the early capillary plexus in the control and RA-treated hearts depends on the position of the aorta relative to the pulmonary trunk. In both normal and RA-treated hearts, there are several capillary penetrations to each aortic sinus facing the pulmonary trunk, but eventually only 1 coronary artery establishes patency with 1 aortic sinus.

CONCLUSIONS

The abnormal location of the vessel primordia induces defective courses of coronary arteries; creates fistulas, a single coronary artery, and dilated vessel lumens; and leaves certain areas of the heart devoid of coronary artery branches. RA-evoked heart malformations may be a useful model for elucidating abnormal patterns of coronary artery development and may shed some light on the angiogenesis of coronary artery formation.

Multiple cardiac anomaly in sheep: a case study and review of the literature

A multiple cardiac anomaly in sheep is presented to show how complicated the result of abnormal development can be. The heart of a 12-hour-old sheep was fixed in 8% formaldehyde solution and subsequently dissected by an anatomical method, and the abnormalities were recorded on digital pictures. The abnormal anatomy is described and compared with the simple developmental anomalies. Developmental abnormalities were found in the distal portion of the bulbus, the aortic arches and the interatrial septum. A special type of the double-outlet right ventricle was observed, which was not a real double-outlet ventricle because it occurred in combination with pulmonary atresia. Coarctation of the aorta was seen, the ductus arteriosus was absent, and there were five vessels originating from the aortic arch instead of one vessel seen in normal cases, as a result of the abnormal development of the aortic arches.

Congenital Heart Surgery Nomenclature and Database Project: double outlet right ventricle

Double outlet right ventricle (DORV) is a type of ventriculoarterial connection in which both great vessels arise entirely or predominantly from the right ventricle. Although the presence of aortic-mitral discontinuity and bilateral coni are important descriptors, they should not serve as absolute prerequisites for the diagnosis of DORV. The morphology of DORV is encompassed by a careful description of the ventricular septal defect (VSD) with its relationship to the semilunar valves, the great artery relationships to each other, the coronary artery anatomy, the presence or absence of pulmonary outflow tract obstruction (POTO) and aortic outflow tract obstruction (AOTO), the tricuspid-pulmonary annular distance, and the presence or absence of associated cardiac lesions. The preferred surgical treatment involves the connection of the left ventricle to the systemic circulation by an intraventricular tunnel repair connecting the VSD to the systemic semilunar valve. This ideal surgical therapy is not always possible due to the presence of confounding anatomical barriers. A multitude of alternative surgical procedures has been devised to accommodate these more complex situations. A framework for the development of the DORV module for a pediatric cardiac surgical database is proposed.

Morphogenetic considerations on congenital malformations of the outflow tract. Part 2: Complete transposition of the great arteries and double outlet right ventricle

On the basis of our recent embryologic work concerning the separation process of the outflow tract, our study of the morphology of specimens from the Leiden Collection of malformed hearts, and in conjunction with our review of the literature, we have reconsidered the morphogenesis of complete transposition and double outlet right ventricle. In complete transposition, a mirror-image arrangement of the columns of the aorto-pulmonary septum could explain the discordant ventriculo-arterial connexion and might thus play a role in its development. Dedicating a cardinal role to the aorto-pulmonary septum in the morphogenesis of complete transposition does not, however, seem justified. Double outlet right ventricle is not an embryologic entity. From the stance of the embryologist, we prefer to consider double outlet right ventricle in terms of a feature that may occur in specimens related to hearts with either a concordant ventriculo-arterial connexion (such as tetralogy of Fallot, or the so-called Eisenmenger ventricular septal defect), or a discordant ventriculo-arterial connexion (complete transposition).

Unique variant of Taussig-Bing heart: double-outlet right ventricle with double ventricular septal defects and double overriding of great arteries

A cyanotic, tachypneic newborn was diagnosed to have double-outlet right ventricle of the Taussig-Bing type. Cardiac failure did not respond to medical treatment or surgical palliation. Postmortem examination revealed two ventricular septal defects (VSDs), one a malalignment VSD in the membranous septum and adjacent tissue and the other in the anterosuperior part of the muscular septum. The D-malposed aortic root emerged mainly from the right ventricle, with aortic-mitral continuity. The larger posterolateral pulmonary root arose almost entirely from the right ventricle, confluent with the muscular VSD, and unrelated to the mitral valve. Its right ventricular aspect was obstructed by hypertrophied infundibulum. This unique malformation of the heart functioned as a double-outlet right ventricle of Taussig-Bing type. In addition, however, the malformation had elements of tetralogy of Fallot because of the malaligned VSD and hypertrophied conal musculature (although pulmonary flow was excessive), and also of complete transposition of the great arteries because of the arrangements of the two VSDs, which favored aortic flow from right ventricle and pulmonary blood flow from the left ventricle. Thus, a single heart presented similarities to three anatomic and functional entities.

Fibrous skeleton and ventricular outflow tracts in double-outlet right ventricle

Twenty-four hearts in which both great arteries arose from the right ventricle were studied to establish variations present within the fibrous skeleton and infundibular morphologies. Variations were also noted in the location of the ventricular septal defect and measurements were obtained of the outlet septum and the circumferences of the arterial valves. Completely muscular subarterial infundibulums were present in only 9 (37.5%) of the hearts, with varying degrees of fibrous continuity between the leaflets of the arterial and atrioventricular valves in the remainder. The aorta was rightward and posterior in 12 (50%) of the hearts, and subaortic and subpulmonary ventricular septal defects were present in equal numbers in this group. No subaortic defects were present when the aorta was side-by-side and right-sided. No subpulmonary defects were present in hearts with a posterior aorta. The mean ratio of 0.91 +/- 0.36 for the subpulmonary to subaortic length of the outlet septum was significantly less than the value of 1.54 +/- 0.41 noted previously in hearts with tetralogy of Fallot (p less than 0.001).

Arrested rotation of the outflow tract may explain double-outlet right ventricle

In a previous study the possibility that tetralogy of Fallot and transposition of the great arteries may result of embryonic arrests in the normal rotation of the junction of the outflow tract and the great arteries was investigated. The results suggested that the development of other transposition complexes such as double-outlet right ventricle might also be related to arrests in this process of rotation. To further study this question 20 normal hearts and 15 hearts with double-outlet right ventricle obtained at autopsy were studied. The angle of the aortic-to-pulmonary valve axis relative to the inferior surface of the heart, as viewed from apex to base, was measured from postmortem radiographs. For normal hearts the mean angle was 81 +/- 7(SE) degrees. For 13 of the 15 hearts with double-outlet right ventricle the mean angle was 4 +/- 7(SE) degrees. Two hearts with double-outlet right ventricle showed markedly divergent aortic-to-pulmonary valve angles, with a mean of 228 +/- 11(SE) degrees, and were therefore grouped separately. Although direct comparison of hearts and embryos is difficult because of the differences in methods of determining angles, the valve positions in normal hearts was most similar to Carnegie stage 19, as found in an earlier study. The majority of the hearts with double-outlet right ventricle resembled stage 16 embryos. The results of this study, as well as those of the earlier studies, support the hypothesis that a spectrum of cardiac anomalies with anomalous origin of great vessels arises as arrests in the normal rotation of the semilunar valve region during embryogenesis.

Double outlet right ventricle associated with common atrioventricular canal: report of nine anatomic specimens

Double outlet right ventricle associated with complete atrioventricular (AV) canal is a rare malformation. Nine cases are reported. In this abnormality the anterior AV leaflet is undivided and free floating and the aortic and pulmonary orifices are in the same frontal plane. In four of the nine cases, the conus was bilateral, but it was slightly hypoplastic in two. In five cases there was no subaortic conus and there was mitral-aortic continuity through the ventricular septal defect. Pulmonary stenosis was present in eight cases. Radiograms may best demonstrate the anatomy of the ventricular septal defect; it extends far anteriorly below the aortic valve, and its inferior rim is deviated by the trabecula septomarginalis.

Early prenatal detection of double outlet right ventricle by echocardiography

A double outlet right ventricle with subpulmonary ventricular septal defect and right sided hypoplastic aorta was diagnosed in a 22 week fetus of a mother with diabetes mellitus. Elective termination of pregnancy was carried out and the echocardiographic findings were confirmed. Early prenatal detection of congenital heart disease may allow elective termination of pregnancy when the fetus has severe defects.

Transatrial repair of double-outlet right ventricle in infants

In three infant cases of double outlet right ventricle (DORV), two with normally related great arteries (NGA) and one with side-by-side great arteries, a transatrial repair was carried out. In all three cases, the results were excellent. It is concluded that in the small baby with DORV with NGA and in DORV with side-by-side great arteries with a hypoplastic crista, a transatrial repair should be successful. This is dependent on the VSD being in the perimembranous (and, therefore, subaortic) location and on the absence of infundibular pulmonary stenosis. In all other varieties of DORV the repair should probably be done through the ventricle.

Syndromes of cardiovascular malformations induced by copper citrate in hamsters

Pregnant golden hamsters were injected intraperitoneally on the morning of the eighth day of gestation with a solution of copper citrate (2.7 mg/kg) or deionized water. Embryos were removed from the mothers by laparotomy on the 12th and 13th days of gestation, serially sectioned through the thorax, and examined for cardiac malformations. Twenty-one of the 37 edematous embryos from copper-treated mothers were affected with a total of 58 major cardiac anomalies. Sixteen of these embryos were affected with double outlet right ventricle in association with a membranous ventricular septal defect, two embryos contained hearts with overriding aortas, and three embryos were affected with isolated ventricular septal defects. Eleven of the 16 embryos with double outlet right ventricle were also affected with pulmonary trunk hypoplasia. The concept that these cardiac anomalies arise from a common pathogenetic basis is supported by the present model.

Two dimensional echocardiographic characteristics of double outlet right ventricle

The reliability was evaluated of two dimensional echocardiography in distinguishing double outlet right ventricle from other anomalies of the great arteries. Accordingly, a combined retrospective and prospective study was conducted in 13 children with double outlet right ventricle, 12 with tetralogy of Fallot, 13 with complete d-transposition of the great arteries, 5 with congenitally corrected I-transposition and 2 with truncus arteriosus. Echographic findings using a standard long axis view in all subjects with double outlet right ventricle included (1) inability to identify a great artery arising from the left ventricle, and (2) lack of continuity between the anterior mitral leaflet and any semilunar valve. In the short axis view constant findings were (1) simultaneous imaging of both great arteries in an anterior location with the ventricular septum identified posteriorly on sweeping into the left ventricle, and (2) lack of a clockwise wraparound of the aorta by the right ventricular outflow tract. Imaging revealed that the great arteries were side by side in seven patients d-malposed in three and l-malposed in two. A modified left precordial tomographic view demonstrated both great arteries arising from the right ventricle in four of nine patients not treated surgically. In four patients with surgically repaired double outlet right ventricle, the left ventricular outflow tract had a tunnel-like configuration in the long axis view. These findings were diagnostic of double outlet right ventricle in all patients and accurately differentiated the malformation from other anomalies of the great arteries.

Copper-induced heart malformations in hamsters

The injection of copper citrate into pregnant golden hamsters induces a specific pattern of cardiovascular malformations in their embroys. The syndrome consists of double-outlet right ventricle, pulmonary hypoplasia and a ventricular spetal defect.

Double outlet right ventricle: clinical and anatomical spectrum

Thirty-two patients with double outlet right ventricle (DORV) were studied between 1960 and 1976. Associated congenital defects frequently compounded the difficulty of clinical diagnosis. Cardiac catheterisation was performed in 27 patients, and the ventriculograms were studied with particular regard to the relative positions of the great vessels to each other and to the ventricular septal defect. These relationships determine which corrective operation is possible. Correction has been performed in 12 patients with a perioperative mortality of 25%. Although mitral-aortic discontinuity was demonstrated in all cases, consideration of the anatomical spectrum included in the term DORV suggests that discontinuity is not an essential feature. In common with other clinical data and in contrast with necropsy studies, none of our patients was found to show the normal relationship of the great vessels to each other, in which the aorta lies posterior and to the right of the pulmonary artery. The reason for this difference between the clinical and necropsy findings is not apparent. A similar disparity was shown with regard to pulmonary stenosis, which was demonstrated at catheterisation in 68% of the 27 patients (mean gradient 68 +/- 3 mmHg), in contrast with incidences of 18% and 25% in recent necropsy series. Patients in the necropsy studies were frequently neonates or infants, in whom death may have been the result of intractable cardiac failure secondary to excessive pulmonary blood flow. In older patients without pulmonary stenosis and with pulmonary hypertension, frequent observation is imperative so that surgical treatment can be instituted before the development of irreversible pulmonary vascular disease.

Cross-sectional echocardiography in the diagnosis of congenital heart disease. Identification of the relation of the ventricles and great arteries

Using a mechanical sector-scanner, two-dimensional echocardiograms were obtained from 28 normal subjects, 15 patients with tetralogy of Fallot, 11 patients with complete transposition of the great arteries and six patients with double outlet right ventricle. The image obtained perpendicular to the long axis of the left ventricle at the base of the venticular septum was superimposed on the image obtained perpendicular to the long axis at the origin of the great arteries. In normal subjects, these superimposed images demonstrated that the aorta originated posterior and to the left of the ventricular septum. In patients with tetralogy of Fallot, the aorta was displaced anterior and to the right resulting in the aorta over-riding the ventricular septum. In patients with double outlet right ventricle both great arteries originated anterior to the ventricular septum (i.e., from the right ventricle). In patients with complete transposition, the aorta originated anterior and the pulmonary artery posterior to the ventricular septum. Thus, cross-sectional echocardiography permits noninvasive identification of the relation of the ventricles and great arteries and, therefore, provides important information for the diagnosis of patients with congenital heart disease.

Double outlet right ventricle. Study of 27 cases

Out of 1610 children's hearts with congenital malformations there were 27 specimens showing double outlet right ventricle. Cases with dextrocardia, situs inversus, or l-venticular loop were excluded. Anatomical examination was performed with particular reference to the infundibular region, the great vessels, and the ventricular septum. The commonest associated malformations were ventricular septal defect and pulmonary stenosis. Aortic stenosis was the predominant finding in those cases dying in the neonatal period. An aortic conus was associated with pulmonary stenosis, ventricular septal defect, and d-transposition, a pulmonary conus with ventricular septal defect and a double conus with stenosis of either great vessel. The anterior vessel always had a muscular conus and the posterior vessel was commonly stenotic.

Double outlet right ventricle: hemodynamic and anatomic correlations

There are 16 possible variations of double outlet ventricle with regard to interrelations of the great arteries and to location of the ventricular septal defect. In a series of 62 cases, approximately two thirds of patients had the great arteries in a side by side relation, and most (28 of 41) had the ventricular septal defect in a subaortic position. In double outlet right ventricle with malposition of the great arteries, the ventricular septal defect was either subpulmonary or subaortic. Four of the 13 patients with subpulmonary ventricular septal defect had a supracristal defect with side by side relation of the great arteries (Taussig-Bing anomaly), and 9 patients had malposition of the great arteries with an infracristal ventricular septal defect. In all patients with subpulmonary ventricular septal defect, pulmonary arterial oxygen saturation was greater than systemic arterial saturation regardless of the relation of the great arteries. Forty patients had subaortic ventricular septal defect. In 24 of these patients, including 7 with malposition of the great arteries, systemic arterial oxygen saturation was greater than pulmonary arterial saturation. However, in 9 patients (25 percent) the reverse was true, as seen in complete transposition of the great arteries and in Taussig-Bing anomaly. Thus, pulmonary arterial oxygen saturation greater than systemic arterial saturation is not reliable evidence of a Taussig-Bing anomaly. Of the 25 patients with such saturation, only 4 had the Taussig-Bing anomaly.

Double-outlet right ventricle associated with persistent common atriventricular canal

A variant of double-outlet right ventricle (DORV) associated with common atrioventricular (A-V) canal was identified. As yet, this syndrome has not been successfully repaired. Of 16 patients with this diagnosis, 14 had the diagnosis confirmed at postmortem examination and two had the diagnosis confirmed by exploratory cardiotomy. The 16 patients were divided into two groups according to the position of the cardiac apex: group 1, ten patients with levocardia, and group 2, six patients with dextrocardia and ventricular inverson. When pulmonary stenosis was present, the clinical presentation was similar to that in tetralogy of Fallot, and when such stenosis was not, the presentation was similar to that in ventricular septal defect with bidirectional shunting. The electrocardiogram had the typical feature of common A-V canal. The right ventricular angiocardiogram had features typical of DORV. The left ventricular angiocardiogram revealed left ventricular outflow deformity typical of A-V canal in patients with levocardia but not in those with dextrocardia. Splenic anomalies were commonly seen (nine of the 16 patients). Asplenia was present in seven, and polysplenia in two. Ten patients had persistent left superior vena cava, seven had common atricum, six had anomalous pulmonary venous connection, and three had subaortic stenosis. Twelve of the 16 patients had pulmonary stenosis. Of the 16, 14 had common A-V canal (Rastelli type C) and two had a ventricular septal defect of the persistent common A-V type.

Double outlet right ventricle with spontaneously developing pulmonary outflow obstruction

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His-Tawara bundle in complete AV block complicating double outlet right ventricle with intact interventricular septum

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