Single Atrioventricular Valve Research Articles

Multiple brain abscesses in a newborn with Down syndrome: heart disease or meningeal infection?

Introduction: Cerebral abscess is a rare pathology in the newborn, most often secondary to meningeal involvement, but congenital heart disease is to be feared. Objectives: To review a case of multiple cerebral abscesses in the newborn with a doubtful diagnosis through a clinical case. Observation: Newborn at D6 of life, from a fullterm pregnancy, with a negative infectious anamnesis, admitted for fever at 38. The first one appeared at D4 of life, in whom the clinical examination found an icteric newborn, with a trisomic face, tachycardia at 180bpm, axial hypotonia, FANT and RS+, systolic cardiac murmur and light sub-costal draught. In front of this picture, a lumbar puncture was carried out objectifying a lymphocytic meningitis, At J8 of life, the newborn presented a convulsion, An ETF was carried out objectifying a hypoechogenic image with hyperchogenic border in cocarde evoking an abces confirmed by CT. The echocardium performed as part of the etiological workup, objective a single ventricle, CIA ostium primum large, IVC admission, single atrio ventricular valve, complete atrio ventricular canal, persistence of the ductus arteriosus and Coarctation of the aorta. The newborn was put on parenteral antibiotic therapy based on C3G meningeal dose + vancomycin + metronidazole by intravenous route then oral relay, with a scannographic control and neurological clinical evaluation. In front of this case, the question that arises: are his abscesses secondary to meningitis or to congenital heart disease? Conclusion: Brain abscess is a rare pathology, with heavy after-effects, and the prognosis of patients has improved thanks to the progress of imaging techniques, the use of ATB treatments, and minimally invasive neurosurgery. It is to be feared in front of congenital cardiopathies with right-left shunt.

Multiple Brain Abscesses in A Newborn with Down Syndrome: Heart Disease or Meningeal Infection?

Introduction: Cerebral abscess is a rare pathology in the newborn, most often secondary to meningeal involvement, but congenital heart disease is to be feared. Objectives: to review a case of multiple cerebral abscesses in the newborn with a doubtful diagnosis through a clinical case. Observation: Newborn at D6 of life, from a full-term pregnancy, with a negative infectious anamnesis, admitted for fever at 38. The first one appeared at D4 of life, in whom the clinical examination found an icteric newborn, with a trisomic face, tachycardia at 180bpm, axial hypotonia, FANT and RS+, systolic cardiac murmur and light sub-costal draught. In front of this picture, a lumbar puncture was carried out objectifying a lymphocytic meningitis, At J8 of life, the newborn presented a convulsion, An ETF was carried out objectifying a hypoechogenic image with hyperchogenic border in cocarde evoking an abces confirmed by CT. The echocardium performed as part of the etiological workup, objective a single ventricle, CIA ostium primum large, IVC admission, single atrio ventricular valve, complete atrio ventricular canal, persistence of the ductus arteriosus and Coarctation of the aorta. The newborn was put on parenteral antibiotic therapy based on C3G meningeal dose + vancomycin + metronidazole by intravenous route then oral relay, with a scannographic control and neurological clinical evaluation. In front of this case, the question that arises: are his abscesses secondary to meningitis or to congenital heart disease?. Conclusion: Brain abscess is a rare pathology, with heavy after-effects, and the prognosis of patients has improved thanks to the progress of imaging techniques, the use of ATB treatments, and minimally invasive neurosurgery. It is to be feared in front of congenital cardiopathies with right-left shunt.

The peripartum management of a 32-year-old patient presenting at 34 weeks’ gestation with unrepaired cyanotic heart disease

Unrepaired cyanotic heart disease is considered a high-risk lesion owing to the consequent increase in maternal and fetal complications. In the presence of pulmonary hypertension, maternal mortality approaching 50% has been reported, and pregnancy is therefore considered contraindicated. We present a case of a 32-year-old woman presenting at 34 weeks’ gestation in heart failure due to newly diagnosed cyanotic complex cardiac disease. The diagnosis of left atrial isomerism with a common atrium, single atrioventricular valve, and a restrictive ventricular septum defect was made. Cyanosis was due to mixing at atrial level, without features of Eisenmenger’s syndrome. Her intrapartum multidisciplinary management is described in detail. The patient was discharged home in a condition similar to her baseline, together with her healthy neonate.

A Holey Predicament

SESSION TITLE: Student/Resident Case Report Poster - Cardiovascular Disease II SESSION TYPE: Student/Resident Case Report Poster PRESENTED ON: Tuesday, October 25, 2016 at 01:30 PM - 02:30 PM INTRODUCTION: Endocardial cushion defects are congenital abnormalities that result in valvular dysfunction as well as “holes” in the septa of the heart. With medical advances, these abnormalities are typically diagnosed very early in life. Although survival into adulthood is possible, these patients develop a multitude of complications that can be life threatening. CASE PRESENTATION: A seventy-two year-old female with recently diagnosed atrial fibrillation presented to the emergency room with dyspnea and palpitations. On physical exam, she had an irregular tachycardia and a systolic murmur. Chest radiography demonstrated severe cardiomegaly. An electrocardiogram showed an atrial tachyarrhythmia, possibly multifocal atrial tachycardia. An infusion of diltiazem was started. She converted to sinus rhythm and symptoms improved. A few hours later, she suffered a sudden cardiopulmonary arrest (CPA). CPR was initiated during which intubation was performed. She had return of spontaneous circulation after fifteen minutes but remained severely hypoxic despite multiple ventilator changes and administration of a paralytic agent. However, oxygenation improved with inhaled nitric oxide therapy. An echocardiogram performed prior to the CPA provided some answers; there was a septum primum atrial septal defect measuring 2.3cm with severe pulmonary hypertension and Eisenmengers syndrome. Interestingly, the initially observed right-to-left shunt reversed with the delivery of nitric oxide. A transesophageal echocardiogram showed an aneurysm of the perimembranous portion of the ventricular septum where a ventricular septal defect may have been previously present. A single atrioventricular valve annulus with two separate orifices was present, thus categorizing the endocardial cushion defect as either partial or transitional. A right heart catheterization demonstrated pulmonary artery pressure of 61/6mmHg, pulmonary artery wedge pressure of 13mmHg and ratio of pulmonary to systemic blood flow (Qp/Qs) of three. The patient was not a surgical candidate because of the presence of Eisenmenger syndrome. She recovered with supportive critical care, was extubated and discharged home in stable condition. DISCUSSION: Eisenmenger syndrome is a complication of pulmonary hypertension associated with congenital heart disease whereby increased pulmonary blood flow leads to pulmonary vascular resistance and shunt reversal. These patients are at high risk for developing atrial arrhythmias, heart failure and sudden cardiac death. Surgical correction of the abnormalities is usually performed at an age less than six months and is not recommended after the development of shunt reversal. CONCLUSIONS: This case highlights the diagnostic workup, potential dangerous consequences as well as critical care management of endocardial cushion defects in an adult. Reference #1: Vongpatanasin W, Brickner ME, Hilis LD and Lange RA. The Eisenmenger syndrome in adults. Ann Intern Med. 1998;128(9):745-55. DISCLOSURE: The following authors have nothing to disclose: Shaiva Meka, Daniel Sheldon, Paul Christensen No Product/Research Disclosure Information

Right atrial isomerism in children older than 3years.

BackgroundThere is a high mortality in infants with right atrial isomerism (RAI). However, less is known about outcome in older children with RAI. This study sought to evaluate those patients with RAI who survived older than 3 years of age without surgical intervention.ResultsA total of 33 consecutive patients (20 males) were enrolled in the study, mean age 6 years (range 3–32). None of the patients had surgical intervention for the RAI before age 3. Cardiac abnormalities include altered cardiac position (39 %), atrioventricular valve anomaly (87 %), single or functional single ventricle (55 %), pulmonary/subpulmonary obstruction (97 %), abnormal origin of the aorta (100 %), bilateral superior vena cava (67 %), and anomalous pulmonary venous drainage (66 %). Surgical intervention was performed after 3 years of age in 20 patients (61 %). None of them planned or had biventricular repair performed. 10 patients underwent the total cavopulmonary connection procedure, including four (40 %) who had atrioventricular valve (AVV) repair at the same time [all with common atrioventricular valve (CAVV)]. One patient died the day after the operation. A total of 69 % of patients with a CAVV had moderate or severe regurgitation, while 27 % with a single atrioventricular valve had moderate or severe regurgitation.ConclusionPatients with RAI who have survived to early childhood without surgical intervention have complex cardiac abnormalities. Survival after single stage total cavopulmonary connection is good but AVV repair is common.

Dextrocardia with Cor Biloculare in a 44 Year Old Women

Cor biloculare, a two-chambered heart, is a rare congenital anomaly of the heart. It’s characterized by a single or common atrium communicating with a single or common ventricle by a single atrio-ventricular valve. Most patients with cor biloculare die within neonatal period or even in fetal period, and very few survivors could grow up to adult. In this article, we report an adult case with dextrocardia and cor biloculare, who survived to the 44 years of life.

Congenital heart defects associated with atrial heterotaxy.

To determine the frequency of various congenital cardiac defects associated with atrial heterotaxy and the difference between spectrum of cardiac defects in right atrial isomerism (RAI) and left atrial isomerism (LAI) in these patients. Cross-sectional observational study. Department of Cardiology, The Children's Hospital and Institute of Child Health, Lahore, from July 2006 to June 2011. All children presenting to the hospital with suspected congenital heart defect were included in the study. Echocardiography based sequential segmental analysis was used, taking atrial symmetry, interrupted inferior vena cava (IVC) and juxtaposed aorta to IVC relation into account for identifying atrial heterotaxy. Various segmental defects were noted for RAI and LAI. Children had atrial heterotaxy (M:F; 1.7:1) with 61.6% (n=82) having LAI. Most common lesions associated with RAI included complete atrioventricular (AV) septal defect (n=48, 94.1%), single AV valve (n=45, 88.2%) and pulmonary outflow tract obstruction (n=41, 80.4%). LAI was associated with ventricular septal defect (n=68, 82.9%), atrial septal defect (n=63, 76.8%, mostly secundum variety), and miscellaneous left sided obstructive lesions. Atrial heterotaxy encompasses a wide spectrum of congenital cardiac defects. The frequency of various defects associated with RAI or LAI in local South Asian population of Lahore, Pakistan is similar to those as reported in the Western literature.

Percutaneous Transhepatic Venous Access for Catheter Ablation Procedures in Patients With Interruption of the Inferior Vena Cava

Catheter ablation of left-sided atrial arrhythmias generally is performed using a transfemoral venous approach through the inferior vena cava (IVC). In this report, we assessed the feasibility of a percutaneous transhepatic approach to ablation of left-sided atrial arrhythmias in 2 patients with interruption of the IVC. Patient 1 had atrial flutter in the setting of complex congenital heart disease and prior Fontan for univentricular physiology and a single atrium. Patient 2 had atrial fibrillation. Percutaneous hepatic vein access was obtained with ultrasound and fluoroscopic guidance. Transseptal catheterization was performed in patient 2. After the procedure, the hepatic tract in patient 1 was cauterized using a bipolar radiofrequency catheter, and an Amplatzer vascular plug was used in patient 2 to obtain hemostasis. Percutaneous hepatic vein access was achieved without complications. After electroanatomical mapping, a linear lesion was placed between the single atrioventricular valve and the confluence of the hepatic veins in patient 1; this terminated the flutter, and bidirectional block was achieved. In patient 2, the pulmonary veins were electrically isolated using an extraostial approach, isolating the ipsilateral veins in pairs. Additionally, ablation of right-side atrial flutter was achieved by obtaining bidirectional block across a linear lesion between the tricuspid valve and confluence of the hepatic veins. Hemostasis of the transhepatic tract was attained in both patients. In patients with interrupted IVCs, a percutaneous transhepatic approach is a feasible alternative for performing catheter ablation of complex left-sided arrhythmias.

Anesthetic management of a patient with Meckle-Gruber Syndrome with complex cardiac anomalies for non-cardiac surgery

An 8-month old male patient of Meckle-Gruber Syndrome with a single ventricle with unrestricted pulmonary blood flow leading, moderate ventriculoseptal defect, rudimentary right ventricle and a single atrioventricular valve presented for excision of occipital meningo-encephalocele. Previous banding of pulmonary artery trunk to reduce pulmonary blood flow had failed. Pre-anesthetic examination showed the patient to have pulmonary congestion secondary to excessive blood flow. General anesthesia with judicious use of hyperventilation, nitrous oxide and fluid restriction helped in diverting excess blood flow away from the pulmonary bed and prevented any further deterioration in pulmonary congestion. The strategy helped in a successful outcome from anesthesia in this patient having complex cardiac anomaly coming for non-cardiac surgery.

Interaction of Gata4 and Gata6 with Tbx5 is critical for normal cardiac development

Congenital heart disease is the most common type of birth defect with an incidence of 1%. Previously, we described a point mutation in GATA4 that segregated with cardiac defects in a family with autosomal dominant disease. The mutation (G296S) exhibited biochemical deficits and disrupted a novel interaction between Gata4 and Tbx5. To determine if Gata4 and Tbx5 genetically interact in vivo, we generated mice heterozygous for both alleles. We found that nearly 100% of mice heterozygous for Gata4 and Tbx5 were embryonic or neonatal lethal and had complete atrioventricular (AV) septal defects with a single AV valve and myocardial thinning. Consistent with this phenotype, Gata4 and Tbx5 are co-expressed in the developing endocardial cushions and myocardium. In mutant embryos, cardiomyocyte proliferation deficits were identified compatible with the myocardial hypoplasia. Similar to Gata4, Gata6 and Tbx5 are co-expressed in the embryonic heart, and the transcription factors synergistically activate the atrial natiuretic factor promoter. We demonstrate a genetic interaction between Gata6 and Tbx5 with an incompletely penetrant phenotype of neonatal lethality and thin myocardium. Gene expression analyses were performed on both sets of compound heterozygotes and demonstrated downregulation of α-myosin heavy chain only in Gata4/Tbx5 heterozygotes. These findings highlight the unique genetic interactions of Gata4 and Gata6 with Tbx5 for normal cardiac morphogenesis in vivo.

Atrioventricular Canal: Single-Patch Technique

Complete atrioventricular septal defects have been repaired at the Medical University of South Carolina for the past 25 years using the "single-patch technique" as first described by the Mayo Clinic group in 1968. In this technique, the single atrioventricular valve is separated into left (mitral) and right (tricuspid) components by dividing the superior and inferior bridging leaflets back to the annulus. A single patch of bovine pericardium is sutured to the right ventricular aspect of the ventricular septum, the previously divided valve leaflets are resuspended to the patch, the "cleft" in the left-sided valve is closed with interrupted sutures, and the atrial component of the defect closed by suturing the patch to the atrial septum with a continuous suture. Since 1995, there have been no operative deaths in the 88 consecutive infants undergoing this repair in our institution. Nine patients (10.2%) have required reoperation for severe mitral regurgitation. While the issue of operative mortality in patients undergoing single-patch repair of complete atrioventricular septal defect has largely been eliminated, residual or recurrent mitral regurgitation continues to be a problem.

Atrial Septal Defects in the Adult

Patients with isolated atrial septal defects (ASDs) have benefited from important recent advances in the diagnosis, evaluation, and management of their conditions. This review will focus on adolescent and adult patients with sizeable ASDs who do not have other major associated cardiac defects. There are 3 major types of ASDs or interatrial communications: ostium secundum, ostium primum, and sinus venosus (Figure 1A) defects. The ostium secundum is a true defect of the atrial septum and involves the region of the fossa ovalis. The ostium primum defect is within the spectrum of the atrioventricular (AV) septal defects (Figure 1B; also known as AV canal defects or endocardial cushion defects), the complete form of which also includes a large ventricular septal defect and a common AV valve. The sinus venosus defect is usually located at the junction of the right atrium and superior vena cava and is almost always associated with partial anomalous pulmonary venous return. Two very uncommon types of ASDs may be mentioned briefly: the inferior vena cava form of the sinus venosus defect and the coronary sinus septal defect (in which a defect between the coronary sinus and the left atrium allows a left-to-right shunt to occur through an “unroofed” coronary sinus). Figure 1. A, A indicates superior sinus venosus ASD; B, secundum ASD; C, inferior sinus venosus ASD; D, ostium primum ASD or partial AV septal defect; E, secundum ASD without posterior septal rim; F, coronary sinus ASD; and IVC, inferior vena cava. B, AV junction viewed from the atrial aspect. Normal indicates normal heart; complete AVSD, complete AV septal defect with a common AV junction and a common, single AV valve, guarded by 5 leaflets (counterclockwise: superior bridging, left mural, inferior bridging, right inferior, and right anterosuperior); partial AVSD, partial AVSD or primum ASD with …

Management of a cadaveric orthotopic liver transplantation in a pediatric patient with complex congenital heart disease

Pediatric orthotopic liver transplantations (OLT) are commonly performed nowadays. Two primary reasons for OLT in children are complications from either extrahepatic biliary atresia (EHBA) or inborn errors of metabolism. However, congenital liver disease may be associated with significant other congenital abnormalities. We present a case of a successful OLT in a pediatric patient with a history of EHBA, situs inversus, and complex congenital heart disease. The cardiac anomalies include dextrocardia, absence of the atrial septum (single atrium), single atrioventricular valve (a-v canal), and an incomplete ventricular septum. Prior surgery include a Kasai procedure for EHBA, banding of the proximal main pulmonary artery, and Broviac catheter placement. We present the anesthesia concerns and management for this complicated case.

Assessment of intracardiac anomalies in two adults with Ivemark's syndrome

Ivemark's syndrome consists of intracardiac anomalies, abnormal lobation of the lungs, and abdominal heterotaxy. A frequent intracardiac anomaly seen in Ivemark's syndrome is a common atrium, which is associated with left-to-right shunting. The increased blood flow and resistance within the pulmonary vasculature creates pulmonary hypertension and eventual reversal of the shunt physiology. In the absence of additional cyanotic malformations, survival into adulthood without prior surgical septation of the common atrium depends on the extent of pulmonary hypertension and intracardiac right-to-left shunting. We present two patients with a common atrium in the setting of Ivemark's syndrome who survived into adulthood without prior operation. Two-dimensional echocardiography assessed their intracardiac structures. One patient had right atrial isomerism manifested by asplenia and a common atrium, into which the hepatic veins drained directly, and the other patient had left atrial isomerism manifested by polysplenia, a common atrium, and a ventricular septal defect with a single atrioventricular valve. Neither patient had additional cyanotic malformations, including obstruction to pulmonary venous return, transposition of the great vessels, or pulmonic valve stenosis. The 2-dimensional echocardiogram guides the clinician to refer patients for surgical septation of the common atrium before the right-to-left shunt physiology predominates. The medical and surgical treatment of these patients is discussed.

Re: In vivo model for reversal of pulmonary blood flow in canines.

It is with interest I read a Letter to the Editor titled `In vivo model for reversal of pulmonary blood ow in canines' by Dan Abramov, Boris Orlov, and Yoram Abramov in your journal of August 1999 [1]. I must congratulate the authors in reviving an interest in this subject. We published an article in International Research Communication System entitled `Reversed pulmonary circulation ± possible clinical application in single ventricle deformity' in 1979 [2]. In the article we described two in vivo canine models that we developed to show that satisfactory oxygenation could be achieved by reversing the blood ow in the lungs. Ten dogs were used in this study. In the ®rst four dogs, on cardio-pulmonary bypass and cardioplegic arrest the right atrium was opened and both the atrio-ventricular valves were sutured closed after excising the atrial septum and the right atrium closed. The blood returning towards the right ventricle through the pulmonary arteries was redirected through a valved conduit in to the left ventricle through the apex (see Fig. 1 in original article). The dogs were weaned off bypass and kept alive for 2 h on ventilation with room air. One dog failed to come off bypass because of air embolus into the coronaries. In the second group of six dogs, we developed a model without using any prosthetic material. On bypass, the right atrium was opened and the atrio-ventricular valve was closed. The atrial septum was detached from its right border and sutured posterior to the right pulmonary veins. The left lung was excluded by snaring the hilum. The left atrium was anastamosed to the left pulmonary artery at the appendage thus redirecting the blood returning from the right lung through the right pulmonary artery in to the left atrium and then on to the aorta (see Fig. 2 in original article). All the six dogs survived the surgery with good oxygenation for over 2 h when the experiment had to be terminated, as we were not licensed to conduct survival experiments. This study reinforced the belief that normal life is possible with the blood circulating the wrong way around in our lungs. We used this haemodynamic turn-about to suggest a new operative procedure for single ventricle deformity in children. The proposed operation carried out with cardio-pulmonary bypass with or without circulatory arrest consists of closing both or single atrio-ventricular valve, as the individual anatomy requires after excising the interatrial septum. The pulmonary valve is then excised with a cuff of pulmonary artery and resutured upside down so that the single ventricle can now eject only through the aorta. A bioprosthetic conduit may have to be used in rare anatomical situations. The advantages that one can see in this operation are (a) the operation can be carried out without damaging the ventricle and (b) in most cases, no prosthetic material is needed.

Unusual Variation of Asplenia Syndrome.

The case of a 1-year-old cyanotic boy diagnosed with asplenia syndrome has been reported. By physical and laboratory examinations, levocardia, atrial inversion, primum ASD, single atrioventricular valve, single ventricle (left-hand morphology), rudimentary right ventricle (anterior, left-sided), pulmonary stenosis, left-sided vena cava, single vena cava superior were established and the case was diagnosed with asplenia syndrome. The patient has concordance between tracheo-bronchial situs and lung anatomy and inverted atrial and visceral situs, but without atrial isomerism that makes his case an unusual variation of asplenia syndrome.

Valve Replacement in the Right Side of the Heart in Children: Long-Term Follow-up

Twenty-five patients (16 male, 9 female) underwent right-sided valve replacement (10 pulmonary valve replacement, 14 tricuspid valve replacement, 3 tricuspid plus pulmonary valve replacement, and 2 replacements of a single atrioventricular valve) at the University of Nebraska Medical Center from June 1977 to December 1986. Twenty-one patients (84%) are long-term survivors with 2,035 months follow-up (range, 41 to 143 months; mean, 96.9 months). Twenty-three Carpentier-Edwards bioprosthetic valves, one Ionescu-Shiley bioprosthetic valve, and nine St. Jude Medical valves were inserted. Follow-up of 17 patients with a Carpentier-Edwards valve ranged from 5 years 9 months to 11 years 9 months (mean, 8 years 11 months). To date there has been one reoperation after 3 years 4 months in this group. One patient who received an Ionescu-Shiley bioprosthesis required re-replacement at 20 months after operation. Three of 4 patients who received St. Jude mechanical valves and are long-term survivors have required replacement after 36 to 56 months. We conclude that the Carpentier-Edwards bioprosthetic valve is a viable option in the right side of the heart in the young age group when annular size is adequate to accommodate an appropriate bioprosthesis.

Progressive atrioventricular valvular regurgitation in single ventricle

The hemodynamic status of the patient with single ventricle is not static. This study describes the rapid development of mechanical malfunction of the atrioventricular (AV) valve in a subset of patients with single ventricle. Eighty patients with single ventricle were reviewed. Eight patients with single ventricle and single AV valve were observed to have moderate to severe AV valvular regurgitation. Patient age when AV regurgitation was first detected was 22 months to 35 years (median 15 years). Clinically, all patients were symptomatic and had severe congestive heart failure. All patients underwent cardiac catheterization, which revealed moderate to severe AV regurgitation; 7 of 8 patients had well preserved ventricular function. Earlier catheterization revealed no significant AV regurgitation. Four patients underwent surgery: 2 had AV valve replacement with the Fontan procedure and 2 had Carpentier ring placement (1 with the Fontan procedure). The 3 survivors were in improved clinical condition. At surgery 1 patient had an abnormal AV valve with 4 leaflets, and the other 3 had myxomatous degeneration of the AV valve. Thus, AV regurgitation is a significant and specific complication that occurs in patients with single ventricle and single AV valve. I recognized before development of eventual myocardial dysfunction, surgical management should be considered.

Magnetic resonance imaging in patients with congenital heart disease.

Magnetic resonance imaging (MRI) was conducted with use of the spin-echo technique (0.35 Tesla) in 22 patients with a variety of congenital and cardiovascular anomalies and in 16 normal volunteers. Electrocardiographic (ECG) synchronization of the data acquisition produced transverse, parasagittal, and coronal tomograms that were used to define size and relationship of the great vessels and internal cardiac structures. MRI findings were corroborated by angiography and sector-scan echocardiography. In most patients the diagnosis had been established before the MRI study. MRI detected all of 11 abnormalities at the level of the great vessels, all of six atrial septal abnormalities, and 10 of 11 ventricular septal defects. Images of poor quality resulting from patient motion were obtained in the one instance in which a small ventricular septal defect was not imaged. Of two patients with Ebstein's anomaly, the displacement of the tricuspid leaflets was shown in one patient but was not evident in another. Complex anomalies such as double-outlet right ventricle, uncorrected L-transposition, single atrioventricular valve, single ventricle, and common ventricle were clearly shown by MRI. Initial experience with MRI has indicated the effectiveness of this technique for defining great vessel and internal cardiac anatomy in patients with congenital heart disease. This is accomplished without the use of contrast media and is thus a completely noninvasive technique for cardiovascular diagnosis.

Double-outlet right atrium with two atrioventricular valves and left atrial outlet atresia

In double-outlet atrium either the right or the left atrium empties into both ventricles while the other atrium remains disconnected from the ventricular cavities. Cases of double-outlet atrium with a single atrioventricular (AV) valve have been reported but no cases of double-outlet left atrium and only two of double-outlet right atrium (one with three valves) have been reported. A description of the second case of double-outlet right atrium with two AV valves and a review of the other reported case are presented. Common anatomic characteristics were: two AV valves in the right atrium that connected with two normal ventricles; disconnection of the left atrium from the ventricular cavities; an atrial septal defect in a malpositioned atrial septum; and drainage of a left superior vena cava into the left atrium. Mitral incompetence was found in both cases. Clinical findings were similar to those seen in ostium primum atrial septal defect. Two-dimensional echocardiography and angiocardiography are able to accurately demonstrate this entity. Successful surgical correction was performed in both cases. Two morphogenetic hypotheses are proposed: abnormal development of the septum primum or primitive malposition of the common atrioventricular canal.