Clinical Presentation and Therapy of Tetralogy of Fallot and Double-Outlet Right Ventricle.

Tetralogy of Fallot (TOF) is the most common cyanotic heart defect. TOF consists of the combination of four anomalies (Fig. 35.1): (1) a large malalignment ventricular septal defect, (2) an obstruction of the right ventricular outflow tract (usually infundibular and valvular pulmonary stenosis with a small pulmonary valve annulus and supravalvular stenosis, (3) an aorta that "overrides" the ventricular septal defect, and (4) right ventricular hypertrophy. TOF represents 4-8% of congenital heart defects. Specific variations of TOF include all forms of pulmonary atresia with VSD and absent pulmonary valve syndrome. In addition, the left and right main pulmonary arteries may be stenotic or hypoplastic. In these cases, there may be major aortopulmonary collateral arteries (MAPCAs) which are vessels arising from the aorta or the subclavian arteries that supply segments of the pulmonary arterial tree. Additional variations include an ASD (Pentalogy of Fallot), a right aortic arch, and coronary abnormalities.

Molecular Pathways and Animal Models of Tetralogy of Fallot and Double Outlet Right Ventricle.

Tetralogy of Fallot and double-outlet right ventricle are outflow tract (OFT) alignment defects situated on a continuous disease spectrum. A myriad of upstream causes can impact on ventriculoarterial alignment that can be summarized as defects in either i) OFT elongation during looping morphogenesis or ii) OFT remodeling during cardiac septation. Embryological processes underlying these two developmental steps include deployment of second heart field cardiac progenitor cells, establishment and transmission of embryonic left/right information driving OFT rotation and OFT cushion and valve morphogenesis. The formation and remodeling of pulmonary trunk infundibular myocardium is a critical component of both steps. Defects in myocardial, endocardial, or neural crest cell lineages can result in alignment defects, reflecting the complex intercellular signaling events that coordinate arterial pole development. Importantly, however, OFT alignment is mechanistically distinct from neural crest-driven OFT septation, although neural crest cells impact indirectly on alignment through their role in modulating signaling during SHF development. As yet poorly understood nongenetic causes of alignment defects that impact the above processes include hemodynamic changes, maternal exposure to environmental teratogens, and stochastic events. The heterogeneity of causes converging on alignment defects characterizes the OFT as a hotspot of congenital heart defects.

Human Genetics of Tetralogy of Fallot and Double-Outlet Right Ventricle.

Tetralogy of Fallot (TOF) and double-outlet right ventricle (DORV) are conotruncal defects resulting from disturbances of the second heart field and the neural crest, which can occur as isolated malformations or as part of multiorgan syndromes. Their etiology is multifactorial and characterized by overlapping genetic causes. In this chapter, we present the different genetic alterations underlying the two diseases, which range from chromosomal abnormalities like aneuploidies and structural mutations to rare single nucleotide variations affecting distinct genes. For example, mutations in the cardiac transcription factors NKX2-5, GATA4, and HAND2 have been identified in isolated TOF cases, while mutations of TBX5 and 22q11 deletion, leading to haploinsufficiency of TBX1, cause Holt-Oram and DiGeorge syndrome, respectively. Moreover, genes involved in signaling pathways, laterality determination, and epigenetic mechanisms have also been found mutated in TOF and/or DORV patients. Finally, genome-wide association studies identified common single nucleotide polymorphisms associated with the risk for TOF.

Recent advances in multimodal imaging in tetralogy of fallot and double outlet right ventricle.

PURPOSE OF REVIEW: In the ever-evolving field of medical imaging, this review highlights significant advancements in preoperative and postoperative imaging for Tetralogy of Fallot (TOF) and double outlet right ventricle (DORV) over the past 18 months. RECENT FINDINGS: This review showcases innovations in echocardiography such as 3D speckle tracking echocardiography (3DSTE) for assessing right ventricle-pulmonary artery coupling (RVPAC) and Doppler velocity reconstruction (DoVeR) for intracardiac flow fields evaluation. Furthermore, advances in assessment of cardiovascular anatomy using computed tomography (CT) improve the integration of imaging in ablation procedures. Additionally, the inclusion of cardiac magnetic resonance (CMR) parameters as risk score predictors for morbidity, and mortality and for timing of pulmonary valve replacement (PVR) indicates its significance in clinical management. The utilization of 4D flow techniques for postoperative hemodynamic assessment promises new insights into pressure mapping. Lastly, emerging technologies such as 3D printing and 3D virtual reality are expected to improve image quality and surgical confidence in preoperative planning. SUMMARY: Developments in multimodality imaging in TOF and DORV are poised to shape the future of clinical practice in this field.

Navigating the spectrum of double-outlet right ventricle presentations: Outcomes from a contemporary cohort based on subtypes.

PURPOSE: Our aim in this study was to investigate the prenatal and postnatal prognosis of double outlet right ventricle (DORV) cases diagnosed prenatally by analyzing the outcomes based on the subtype. METHODS: This study is a retrospective chart review. Cases diagnosed with fetal DORV by prenatal ultrasound in the maternal-fetal medicine department of our hospital between 2014 and 2022 were included. Data on maternal characteristics, fetal echocardiographic features (type of DORV), pregnancy and neonatal outcomes (termination of pregnancy [TOP], intrauterine fetal death [IUD], neonatal death [NND], death in infancy (IND), survival) were collected and analyzed. RESULTS: Ninety-nine cases of prenatally diagnosed cases of DORV were included. The prenatal diagnosis was right in 97% of the liveborn fetuses. The cases were classified into subtypes, including transposition of great arteries (TGA), Fallot, ventricular septal defect (VSD), remote, and heterotaxy types. The cohort consisted of 32.3% TGA type, 19.1% fallot type, 11.1% VSD type, 2% remote type, and 35.3% heterotaxy type of DORV. An additional cardiac anomaly was observed in 87% and an extra-cardiac anomaly was observed in 54% of the cases. When we excluded the cases with heterotaxy type but without any chromosomal abnormality, additional genetic abnormalities were detected in 42% of the remaining cases. Outcome of pregnancy was livebirth in 68/99 (68.7%), IUFD in 5/99 (5.1%), and TOP in 26/99 (26.3%). Postnatal cardiac surgical repair was performed in 48 cases. Survival among livebirths was 39/68 (57.3%). Twenty-nine neonates or infants who had additional cardiac anomalies and/or genetic abnormalities died before any surgical intervention. The postoperative survival rate was 39/48 (81.2%). CONCLUSION: The prognosis in DORV depends on the anatomical subtype, the presence, and severity of associated anomalies. Survival increases in isolated cases without any additional structural or genetic anomalies.

En Bloc Rotation of the Outflow Tracts - Double Root Translocation.

En bloc rotation of the outflow tracts or double root translocation offers an anatomic repair of transposition of the great arteries, ventricular septal defect, and left ventricular outflow tract obstruction and closely related forms of double outlet right ventricle. The technical principle is to excise aortic and pulmonary root en bloc, rotate them as a whole by 180°, and reimplant them. The left ventricular outflow tract is enlarged with the patch closing the ventricular septal defect. In our experience, two thirds of the pulmonary valves could be preserved. Growth of the aortic and pulmonary root could be demonstrated in several studies performed by our group. It is still a complex and technically demanding procedure with long cardiopulmonary bypass periods and cross-clamp times. However, perioperative mortality and complications do not differ significantly from other forms of reconstruction. The reoperation rate is significantly lower. Presently, the best time to perform this operation seems to be after the newborn period within the first year of life.

Double outlet right ventricle - the 50% rule has always been about the conus.

PURPOSE OF REVIEW: There has been much variability in the definition of double outlet right ventricle (DORV) spanning the last century. Historically, emphasis has been placed on the assignment of the great arteries to the right ventricle as a definition of DORV. In this review, we aim to underscore the importance of conal muscle, rather than rules surrounding assignment of great arteries to ventricles. We will be outlining the variability in patient anatomy that results from variations in conal muscle development in DORV, which may not fit perfectly into predefined constructs. This anatomic variability directly determines physiology and surgical repair options. RECENT FINDINGS: There is a growing appreciation of the utility of cross-sectional imaging in complex DORV, and the generation of patient-specific 3D models with virtual reality simulations for surgical planning. These models improve the prediction of candidacy for biventricular repair and allow the mapping of complex baffle pathways preoperatively. SUMMARY: DORV is not a disease entity in itself, but rather a vast spectrum of disorders associated with maldevelopment of conal muscle and often abnormal expansion of one the great vessels. Patient-specific 3D models will be crucial for improved surgical planning and patient outcomes.

Different leadless pacemakers working in harmony (Aveir in the atrium/Micra AV2 in the ventricle) in a patient with dextrocardia and double outlet right ventricle after high-risk infected device extraction.

INTRODUCTION: Patients with congenital heart disease are at increased risk for requiring cardiac pacing during their lifetime. METHODS: We present the first described case of using two leadless pacing systems manufactured by separate companies implanted within the same patient to provide atrial and ventricular pacing due to complex congenital anatomy. RESULTS: A 27-year-old male with dextrocardia with double outlet right ventricle, subaortic ventricular septal defect, and pulmonary stenosis status-post pulmonary valve replacement complicated by ventricular pacing dependence and subsequent atrial pacing dependence after atriotomy-based atypical flutter ablation developed recurrent mediastinitis and pocket infection with erosion despite prolonged antibiotic treatment. Due to atrial and ventricular pacing dependence, a comprehensive congenital care team concluded the need for lead extraction and replacement of pacemaker via leadless peacemaking device. Laser-lead extraction and temporary atrial pacemaker placement was performed. Afterward, a transesophageal echocardiogram guided implantation of both a Micra AV 2 (Medtronic) leadless pacemaker in the interventricular septum within the right ventricle and an Aveir (Abbott) leadless pacemaker in the superior base of the right atrial appendage was performed with successful pacing. Although there is no communication between these devices, atrial-mechanical ventricular pacing was reliable with good implant thresholds, impedances and sensing from both devices. CONCLUSION: Our case demonstrates the feasibility of using dual leadless pacing modalities to simultaneously pace someone at complex, prohibitive risk for temporary permanent or permanent pacemaker devices.

The retirement years of Doctor Helen B. Taussig: an intersection of art and medicine.

Dr Helen B. Taussig (1898-1986) worked a paediatric cardiologist at the Johns Hopkins University in Baltimore, Maryland from 1930 to 1963. Dr Taussig would become world-renowned for her contributions to the systemic-to-pulmonary artery shunt to treat congenital heart patients with cyanosis. This shunt would eventually be named after the surgeon/cardiologist as the Blalock-Taussig shunt. Dr Taussig's name was also attached to the description of one form of double outlet right ventricle called the Taussig-Bing malformation. Dr Taussig ultimately received the Presidential Medal of Freedom in 1964 as a testimony to her life-long contributions to the field of congenital heart surgery.In 1963, Dr Taussig retired from clinical practice but continued her teaching and academic pursuits at Johns Hopkins for another 14 years. Upon her "second retirement" in 1977, she moved to Kennett Square, PA. This paper will review the retirement years of Dr Helen Taussig and the curious intersection between art and medicine.

Outcomes of neo-aortic valve and root surgery late after arterial switch operation.

BACKGROUND: Neo-aortic root dilatation and valve regurgitation are emerging problems late after arterial switch operation (ASO). We sought to evaluate the prevalence and outcomes of neo-aortic root or valve reoperation after ASO. METHODS: All patients with biventricular circulation who underwent an ASO between 1983 and 2015 were included at a single institution. RESULTS: In our cohort of 782 late ASO survivors, the median duration of follow-up was 18.1 years (interquartile range [IQR], 11.3-25.6 years). During follow-up, 47 patients (6.0%) underwent 60 reoperations on the neo-aortic valve/root. The first neo-aortic valve/root reoperation occurred at a median of 15.2 years (IQR, 7.8-18.4 years) after ASO. Operations included mechanical Bentall (31.9%; n = 15), aortic valve repair (25.5%; n = 12), mechanical aortic valve replacement (AVR) (21.3%; n = 10), valve-sparing root replacement (19.1%; n = 9), and the Ross procedure (2.1%; n = 1). There was 1 late death (2.1%). Multivariable predictors of neo-aortic valve/root reoperation were bicuspid valve (hazard ratio [HR], 4.8; 95% confidence interval [CI], 2.1-10.7; P < .001), Taussig-Bing anomaly (HR, 3.0; 95% CI, 1.2-7.4; P < .02), previous pulmonary artery band (HR, 2.8; 95% CI, 1.2-6.3; P < .01) and left ventricular outflow tract obstruction before ASO (HR, 2.4; 95% CI, 1.0-5.8; P < .04). Freedom from neo-aortic valve or root reoperation was 98.0% (95% CI, 96.7%-98.8%) at 10 years, 93.3% (95% CI, 90.8%-95.2%) at 20 years, and 88.5% (95% CI, 84.1%-91.8%) at 30 years after ASO. Among the 47 patients who underwent neo-aortic reoperation, freedom from AVR was 82.3% (95% CI, 67.7%-90.7%) at 10 years, 58.0% (95% CI, 41.8%-71.2%) at 20 years, and 43.2% (95% CI, 27.0%-58.3%) at 25 years after ASO. CONCLUSIONS: The need for neo-aortic valve or root reoperation surpasses 10% by 30 years post-ASO. Evolving understanding of the mechanisms of neo-aortic valve insufficiency and techniques of neo-aortic valve repair may decrease the need for AVR.

Intracardiac Three-Dimensional Image as Surgical Decision-Making Tool of Congenital Heart Disease.

This study aimed to evaluate the anatomical reproducibility of a preoperative intracardiac 3D image (IC image) created using computed tomography, and to investigate its usefulness as a surgical decision-making tool. Between 2012 and 2022, ventricular septal defect (VSD) patients, and double outlet right ventricle (DORV) or transposition of the great arteries (TGA) with pulmonary stenosis (PS) patients who underwent cardiac surgery and had preoperative computed tomography were enrolled. SYNAPSE VINCENT® (Fujifilm) was used to create an IC image which was analyzed retrospectively. In 14 VSD patients, the diagnostic consistency rate in the Soto classification with intraoperative findings was 100% (14/14) for IC image versus 64% (9/14) for transthoracic echocardiography (P = 0.04). The defect size showed a higher correlation coefficient with IC image (0.837, P = 0.001) than with transthoracic echocardiography (0.567, P = 0.034). In 11 DORV/TGA with PS patients, the diagnostic consistency rate in the Lev classification was 100% (9/9) for IC image versus 77% (7/9) for transthoracic echocardiography (P = 0.47). The secondary interventricular foramen (SVF)/left ventricular outflow tract (LVOT) ratio by IC image was significantly smaller in the biventricular-repair group (median 0.71, IQR 0.67-1.06) than in the univentricular-repair group (median 1.79, IQR 1.53-2.42) (P = 0.006). An IC image is useful as a surgical decision-making tool for simple VSDs and complex congenital heart diseases such as DORV or TGA with pulmonary stenosis. The SVF/LVOT ratio determined from the IC image may be a useful indicator for avoiding LVOT obstruction.

The Arterial Switch Operation in the Developing World: Risk Factors and Current Outcomes.

BACKGROUND: Published data on the outcomes of the arterial switch operation in the developing world are limited. We sought to identify the midterm outcomes of and risk factors for mortality and morbidity in patients undergoing the arterial switch operation at a high-volume center in Vietnam. METHODS: A retrospective review was conducted of 608 patients who underwent an arterial switch operation for the treatment of transposition of the great arteries (TGA; n = 509) or double-outlet right ventricle TGA (DORV-TGA; n = 99) at a single center from 2010 to 2021. RESULTS: Overall early mortality was 5.9%, and late mortality was 1%. Multivariate Cox regression showed weight at operation of <3 kg (P < .001), prolonged aortic cross-clamp time (P < .001), and need for secondary aortic cross-clamp (P = .011) as risk factors for overall mortality. The actuarial 10-year survival rate was 93%. The overall cardiac reoperation rate was significantly higher in patients with DORV-TGA (hazard ratio [HR], 16.43; 95% CI, 4.70-57.43; P < .001). The rate of freedom from cardiac reoperation at 10 years was 94%. Risk factors for outflow tract reoperation were patients with DORV-TGA (HR, 23.28; 95% CI, 2.86-189.66; P = .003), single coronary artery (HR, 4.1; 95% CI, 1.16-14.46; P = .028), and mild aortic valve regurgitation observed in 3.7% of patients. CONCLUSIONS: The outcomes of the arterial switch operation in a low- and middle-income country were satisfactory. Nevertheless, the complexity of the procedure and lower weight of patients are still challenges. Patients with DORV-TGA and single coronary artery need to be closely followed up.

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.

Congenital Heart Disease Illustrated: Use of Cross-sectional Imaging in Pediatric Cardiology.

In the modern era of cardiac imaging, there is increasing use of cardiac computed tomography and cardiac magnetic resonance for visualization of congenital heart disease (CHD). Advanced visualization techniques such as virtual dissection, 3-dimensional modeling, and 4-dimensional flow are also commonly used in clinical practice. This review highlights such methods in five common forms of CHD, including double outlet right ventricle, common arterial trunk, sinus venosus defects, Tetralogy of Fallot variants, and heterotaxy, providing visualizations of pathology in both conventional and novel formats.

Long-term results after the réparation à l'étage ventriculaire procedure for transposition of the great arteries and double-outlet right ventricle with pulmonary stenosis.

OBJECTIVES: The purpose of this study is to describe the long-term results of the 'réparation à l'étage ventriculaire' (REV) technique for double-outlet right ventricle and transposition of the great arteries (TGA) with pulmonary stenosis (PS). METHODS: Between 1980 and 2021, 157 patients underwent a REV procedure (median age and weight: 20.8 months and 7.7 kg). The most frequent anatomical presentation was the association between TGA, ventricular septal defect and PS (n = 116, 73.9%). RESULTS: Sixty-seven patients (42.7%) underwent a Rashkind procedure, and 67 patients (42.7%) a prior surgical palliation (including 62 systemic-to-pulmonary artery shunts). Resection of the conal septum and/or ventricular septal defect enlargement was performed in 109 patients (69.4%). Thirteen patients (8.3%) died, including 4 during the first postoperative month and 2 after heart transplant. Overall survival at 40 years was 89.3%. Thirty-seven patients (23.6%) required 68 reinterventions on the right ventricular outflow tract (RVOT), including 49 reoperations, with a median delay of 9 years after the REV (8 months to 27 years). Twenty patients (12.7%) underwent RVOT valvulation (16 surgical and 4 interventional). Freedom from RVOT reintervention and reoperation at 40 years were 60.3% and 62.6%, respectively. Four patients (2.5%) required reoperation for left ventricular outflow tract obstruction, with a median delay of 4.8 years. CONCLUSIONS: The REV procedure is a good alternative for TGA and double-outlet right ventricle with PS patients. Only a quarter of the patients required redo surgery on the RVOT. Reoperations for left ventricular outflow tract obstruction are scarce.

Complex cyanotic congenital heart disease and cervical spine surgery: Ticking all the right boxes.

Although complex congenital heart disease (CHD) patients usually present in childhood, it is not rare to see adults well past middle age. These patients undergo continuous pathophysiological changes in their heart and blood vessels, making anesthetic management more challenging if surgery is required. Herein, we report a case in which understanding the anatomy and pathophysiology helped optimally manage a patient with a double outlet right ventricle (DORV) who underwent plating and fixation for a hangman's fracture in the prone position.

Atrioventricular conduction recovery immediately after the re-operation in a repaired CHD patient.

This is a case of a 2.7-year-old girl with trisomy 21 and double outlet right ventricle who underwent epicardial pacemaker system placement for a surgical atrioventricular block and achieved atrioventricular conduction recovery immediately after residual ventricular septal defect closure. Although ventricular pacing ratio was 100% before re-operation, it declined to approximately 25% on the 6th post-operative day and was <1% 3 years after re-operation.

A retrospective study of congenital cardiac malformations in 29 goats.

Cardiac malformations are sporadically diagnosed in domestic species; however, little literature is available for this group of developmental anomalies in goats. We performed a retrospective study to catalog congenital cardiac conditions in goats submitted to the University of California-Davis, Veterinary Medical Teaching Hospital, Anatomic Pathology Autopsy Service. From 2000 to 2021, of 1,886 goat autopsies, 29 cases of cardiac malformations were identified (1.5%). Thirteen were ≤ 2-wk-old, 8 were 1-6-mo-old, and 8 were adults 2-9-y-old. The most common malformations were ventricular septal defect (VSD; 21 of 29), atrial septal defect or persistent foramen ovale (10 of 29), and double-outlet right ventricle (3 of 29). Nine cases had > 1 malformation, typically including a VSD. Conditions that had not been reported in the goat included double-outlet right ventricle (3), tetralogy of Fallot (1), cor triatriatum sinister (1), and mitral valve dysplasia (1). Two adult cases were incidental and not suspected clinically. Cardiac malformations occur not uncommonly in goats and should be considered in a wide age range.

Coração em Criss-Cross: um relato de caso / Criss-Cross Heart: a case report

Coração em criss-cross (ou coração entrecruzado) foi descrito pela primeira vez em 1974. Trata-se de uma malformação cardíaca congênita, rara, ocorrendo 8 casos a cada 1.000.000 de crianças, e representando somente 0,1% das malformações congênitas. Os métodos diagnósticos de escolha são o ecocardiograma transtorácico, a ressonância magnética cardíaca (RMC), a angiotomografia (TC) e, eventualmente, o cateterismo cardíaco. Neste relato, descreve-se o caso de um recém-nascido com coração em criss-cross somado à dupla via de saída do ventrículo direito (VD), com vasos mal posicionados, além de comunicação interatrial (CIA), comunicação interventricular (CIV), displasia de valva tricúspide e veia cava superior esquerda persistente. Não se sabe a etiologia exata dessa malformação, mas parece ocorrer pela rotação dos ventrículos em seu eixo longitudinal, não acompanhada das rotações atrial e das valvas atrioventriculares (AV). Esse movimento produz uma alteração das vias de entrada dos ventrículos, determinando que o VD se posicione em plano superior e o esquerdo em plano inferior. Apesar de ainda não se saber a exata causa dessa anomalia, acredita-se que uma alteração genética possa estar levando a esses casos: a mutação do gene Cx43. O diagnóstico do caso em questão foi dado pela ecocardiografia transtorácica e da TC de aorta e artérias pulmonares, que mostraram, além do criss-cross, outras alterações, como dupla via de saída do VD, CIA e CIV amplas.(AU)

Criss-cross heart was first described in 1974. It is a rare congenital heart malformation that occurs in 8 cases per 1,000,000 children, and represents only 0.1% of congenital malformations. The diagnostic methods of choice are transthoracic echocardiography, cardiac magnetic resonance (CMR), computed tomography angiography (CT) and, sometimes, cardiac catheterization. This report describes the case of a newborn with a criss-cross heart in addition to double-outlet right ventricle (RV), with poorly positioned vessels, in addition to atrial septal defect (ASD), interventricular septal defect, tricuspid valve dysplasia and persistent left superior vena cava. The exact etiology of this malformation is not known, but it seems to occur due to rotation of the ventricles in their longitudinal axis, not accompanied by rotation of the atrial and atrioventricular (AV) valves. This movement produces abnormal ventricular inlets, determining that the RV be positioned on a superior plane and the left ventricle on an inferior plane. Although the exact cause of this anomaly is still unknown, it is believed that a genetic abnormality may be leading to these cases: mutation of the Cx43 gene. Diagnosis of the case concerned was given by transthoracic echocardiography and computed CT of the aorta and pulmonary arteries, which showed, in addition to the criss-cross heart, other abnormalities, such as double-outlet RV, large ASD and ventricular septal defect (VSD).(AU)