The cardiac malpositions

To flip or not: Case series of coronary angioplasty in patients with right-sided heart

Coronary angioplasty in patients with a right-sided heart may be difficult due to challenges in engaging the coronary arteries, interpreting angiogram, and further delivering intracoronary therapies. We present our experience of percutaneous coronary intervention in two cases and propose a practical algorithm to approach cardiac catheterization in these patients.

Isolated Dextrocardia With Situs Solitus Diagnosed in a Centenarian Patient: A Case Report

This case report presents a rare instance of dextrocardia with situs solitus in a centenarian patient, where the heart is abnormally positioned on the right side of the chest due to embryological development anomalies. The patient, a 102-year-old male with no significant medical history, sought medical attention for cataract surgery and was incidentally found to have a systolic murmur over the left upper sternal border, prompting further evaluation. Echocardiographic assessments revealed moderate aortic stenosis. Further imaging with an upright chest X-ray confirmed the presence of dextrocardia with situs solitus. This intriguing case exemplifies the complexities of diagnosing rare congenital anomalies and underscores the importance of comprehensive evaluations even in elderly patients.

Bilateral subdiaphragmatic renal ectopia with associated congenital anomalies: a case report and systematic review of cases

Background

Cephalad renal ectopia is rare. Ectopic kidneys besides being prone to various pathologies are occasionally associated with other congenital abnormalities. To the best our knowledge, at the time of this writing, only ten cases of bilateral subdiaphragmatic renal ectopia had been reported.

Case presentation: We present a rare case of bilateral subdiaphragmatic ectopic kidneys incidentally discovered during evaluation of the abdominal pain. In addition, our patient had associated anomalies of the liver, spleen and mesocardia.

Conclusions

Recognition of this condition is important for accurate diagnosis, surgical and/or intervention planning, as well as identifying other associated anomalies.

Extended reality visualization of medical museum specimens: Online presentation of conjoined twins curated by Dr. Jacob Henle between 1844-1852

Background:

The purpose of this study is to characterize a full-term conjoined twins’ cadaver curated by Dr. Jacob Henle sometime between 1844 and 1852 and demonstrate digital distribution of an old and rare medical museum specimen using an extended reality (XR) model workflow.

Methods:

The cadaver (Preparation 296) is in the Department of Anatomy and Cell Biology at the University of Heidelberg. An XR display workflow comprises image capture, segmentation, and visualization using CT/MR scans derived from the cadaver. Online radiology presentation to medical students focuses on diagnostic characteristics of anatomical systems depicted with XR models.

Results:

Developmental defects in Preparation 296 include duplicated supradiaphragmatic structures and abnormal osteological features. Subdiaphragmatically, the gut is continuous on the right, but terminates at the distal esophagus on the left. One large liver occupies the abdomen with one spleen located on the left side. Observations suggest duplication of the primitive streak and separate notochords rostrally. Duplication occurs near the yolk sac and involves midgut formation while secondary midline fusion of the upper extremities and ribs likely results from the proximity of the embryos during development. Medical students access the model with device agnostic software during the curricular topic “Human Body Plan” that includes embryology concepts covering mechanisms of twinning.

Conclusions:

The workflow enables ease-of-access XR visualizations of an old and rare museum specimen. This study also demonstrates digital distribution and utilization of XR models applicable to embryology education.

Implantation of a Dual-chamber Pacemaker in a Patient with Dextrocardia, Situs Inversus, and Sick Sinus Syndrome

Situs inversus with dextrocardia is a rare congenital anomaly that presents a unique challenge for the consultant electrophysiologist. Implantation of cardiac device in these patients may be challenging owing to their individual cardiac and vascular anatomy. Consequently, adverse procedural outcomes are more common in this group and an informed pre- and intraoperative approach is critical. In this article, we present the relevant patient findings and implications for the electrophysiologist, including operative approaches. We then examine them in the context of an actual case, having implanted an intracardiac permanent pacemaker with a right-sided approach via the conventional method in a patient with dextrocardia situs inversus who had undergone multiple surgeries for structural heart disease.

Left atrial appendage occlusion in a mirror-image dextrocardia: A case report and review of literature

BACKGROUND

In mirror-image dextrocardia, the anterior-posterior position of the cardiac chambers and great vessels is maintained, but the left-right orientation of the abdominal organs is reversed. The abnormal anatomy of the heart poses surgical challenges and problems in dealing with surgical risk and monitoring complications. There are few reports on closure of the left atrial appendage (LAA) in dextrocardia and no reports on the application of enhanced recovery after surgery (ERAS) following LAA occlusion (LAAO) procedures.

CASE SUMMARY

The objective for this case was to ensure perioperative safety and accelerate postoperative recovery from LAAO in a patient with mirror-image dextrocardia. ERAS was guided by the theory and practice of nursing care. Atrial fibrillation was diagnosed in a 77-year-old male patient, in whom LAAO was performed. The 2019 guidelines for perioperative care after cardiac surgery recommend that the clinical nursing procedures for patients with LAAO should be optimized to reduce the incidence of perioperative complications and ensure patient safety. Music therapy can be used throughout perioperative treatment and nursing to improve the anxiety symptoms of patients.

CONCLUSION

The procedure was uneventful and proceeded without complications. Anxiety symptoms were improved.

[Isomorfismo cardiaco: Una perspectiva multidisciplinaria]

Atrial isomerism describes complex anatomical findings with defects in the determination of lateralization; being a rare situation, with a prevalence of 1 in every 10.000 to 20.000 live births, with an incidence of up to 4% of all cardiac malformations. The diagnosis can be made in the neonatal age; however, clinical presentation is nonspecific. Depending on the spectrum of malformations, complex and invasive diagnostic tools may be required. Treatment is varied and can range from palliative surgery in view of univentricular physiology to total correction surgery for biventricular repair.

Successful Leadless Pacemaker Implantation in an Elderly Patient With Dextrocardia and Situs Inversus

Leadless pacemaker is indicated in patients with symptomatic bradycardia as an alternative therapy when transvenous pacemaker implantation is considered difficult or at high risk. The experience of implanting leadless pacemaker in patients with dextrocardia and situs inversus is limited. A 94-year-old male was transferred to our hospital due to advanced atrio-ventricular block with episode of syncope. Chest radiograph and computed tomography revealed dextrocardia with situs inversus. Emergency cardiac catheterization was performed and a temporary pacemaker was inserted, but the patient removed it due to delirium. So, a leadless pacemaker was implanted to him. Shorter time of bed-rest after the implantation and shorter hospital stay would be beneficial of implanting a leadless pacemaker. Precise anatomical evaluation would be important to perform implantation efficiently and safely.

A Novel Nonsense MMP21 Variant Causes Dextrocardia and Congenital Heart Disease in a Han Chinese Patient

The position and morphology of human internal organs are asymmetrically distributed along the left-right axis. Aberrant left-right patterning in the developing embryo can lead to a series of congenital laterality defects, such as dextrocardia and heterotaxy syndrome. Laterality defects are a genetic condition; however, pathogenic genetic lesions are found in only one-fifth of patients. In this study, whole-exome sequencing was conducted for 78 patients with laterality defects. We identified a novel stopgain variant in MMP21 (c.G496T; p.G166^*) in a Chinese patient with mirror-image dextrocardia. This variant caused a truncated MMP21 mRNA containing only the signal peptide and propeptide, while the coding sequence of matrix metalloproteinase-21 was almost entirely absent. To the best of our knowledge, this novel variant is the first homozygous stopgain variant identified in dextrocardia patients, and the first MMP21 variant found in East Asia. Our findings expand the spectrum of MMP21 variants and provide support for the critical role of MMP21 during left-right patterning in the Han Chinese population.

Dextrocardia: When right is wrong!

Introduction/Background

Dextrocardia is a malposition of the heart in the thoracic cavity. Dextrocardia has been known to cause diagnostic dilemmas with atypical presentations in acute coronary syndrome, as well as technical challenges in patients who require interventions such as coronary catheterization, transcutaneous aortic valve replacement, ablation for arrhythmias, or pacemaker/defibrillator placement. Transcription factor Pitx2 has been shown to have a fundamental role during cardio-genesis, and its misexpression has been implicated in arrhythmogenesis and congenital heart diseases including visceral situs inversus. This association between congenital heart diseases and arrythmias is intriguing and need exploring. We aimed to quantify the likelihood of arrhythmias in patients with dextrocardia.

Materials and Methods

A descriptive, retrospective study was conducted on the National Inpatient Sample (NIS) databases for the year 2016. Patients with dextrocardia and arrhythmias were selected based on appropriate diagnostic codes. We used propensity score-matching to assemble a matched cohort in which adults with dextrocardia and controls balanced on measured baseline characteristics. This was done to reduce the confounding effect of between-group imbalances on outcomes. Complex survey design, weights, and clustering were accounted for during analysis. Multivariate regression analysis was performed to determine the relationship of arrhythmias and length of hospitalization with dextrocardia.

Results

The prevalence of arrhythmias in patients with dextrocardia was significantly higher than the control group. Overall, the odds of arrhythmia were higher for patients in the dextrocardia group when compared to a propensity matched control group [adjusted Odds ratio OR 2.60, Confidence Interval (CI) (1.67-4.06), p<0.001]. When looking at only principal/primary diagnosis on admission, the odds of an admitting diagnosis of arrhythmia were significantly higher in the dextrocardia group when compared to the matched cohort [adjusted OR 3.70, CI (1.26-10.89), p 0.02]. The increased odds of arrhythmia in dextrocardia patients were mostly accounted for by the increased odds of atrial fibrillation/atrial flutter [OR 3.06, CI (1.02-9.18), p 0.046] in these patients. No significant difference was found in the odds of other arrhythmias or the length of stay between the two groups.

Conclusion

In a large inpatient population, patients with dextrocardia were more likely to have arrhythmias especially atrial fibrillation/atrial flutter than patients without dextrocardia. Ours is the first study that investigates the clinical manifestations of molecular and embryologic associations between congenital heart disease and arrhythmias.

A case report of late-onset symptoms of erythrocytosis in univentricular dextrocardia

RATIONALE

Univentricular dextrocardia is a rare congenital heart disease that usually presents cyanotic manifestations from childhood. Due to the sustained dysfunction of blood oxygenation, it is very difficult to keep an asymptomatic survival. Herein, we described an interesting case of univentricular dextrocardia who suffered from initial symptoms in his middle age.

PATIENT CONCERNS

A 54-year-old male patient with numbness and tingling of limbs was admitted to hospital due to the secondary manifestations of congenital heart disease.

DIAGNOSIS

The patient was diagnosed as univentricular dextrocardia with pulmonary hypertension and secondary erythrocytosis based on computed tomography (CT) scan, echocardiography, and laboratory examinations.

INTERVENTIONS

Intravenous hydration therapy with normal saline successfully eliminated his hyperviscosity associated symptoms. In view of socio-economic reasons, this patient refused surgical evaluation and further medical interventions.

OUTCOMES

During 18-month follow up, he received no drug except for regular water intake. Fortunately, his life quality was satisfactory, and no other symptoms emerged except for mild numbness of limbs.

LESSONS

In univentricular dextrocardia, it is possible to keep a long-term asymptomatic period due to the slow progress of pathophysiology. In this population, regular cardiac function evaluation and avoiding dehydration may help improve the quality of life.

Revascularización miocárdica completa con injertos arteriales en un paciente con dextrocardia

La dextrocardia es una rara anomalía cardiaca congénita. Aunque la incidencia de enfermedad coronaria es similar a la población en general, son pocos los casos documentados en la literatura. La disposición anatómica en esta anomalía constituye un desafío a la hora de planificar la técnica quirúrgica y los injertos a utilizar. Presentamos el caso de un paciente de 59 años con enfermedad coronaria de 2 vasos que fue sometido a una cirugía de revascularización arterial completa.

Left atrial isomerism associated with aneurysmal enlargement of right atrial appendage: A case report with literature review

We present a prenatally diagnosed case of heterotaxy syndrome (HS) in which left atrial isomerism (LAI) was associated with an aneurysmal enlargement of the right atrial appendage (RAA). Although LAI is usually associated with complex cardiac and extracardiac anomalies, the association of LAI and right atrial appendage aneurysm (RAAA) is exceptional. Congenital RAAA itself is an idiopathic, very rare cardiac anomaly characterized by the enlargement of the appendage in the absence of any other cardiac or extra-cardiac defect. The prognosis of the heterotaxy is poor with associated major cardiac malformations and even cases with minor cardiac anomalies are at risk postnatally for complications like biliary atresia, intestinal rotational abnormalities, and immune disorders. In this case, the prenatal diagnosis of the isomerism was mainly based on the abnormalities of caval veins. Although no typical complex cardiac anomaly was present, the HS was associated with biliary atresia, polysplenia, and malrotation of the gut. Associated RAAA further imposed an additional risk of complications such as tachyarrhythmias, thromboembolic events, and aneurysmal rupture.

Homozygous loss-of-function mutations in MNS1 cause laterality defects and likely male infertility

The clinical spectrum of ciliopathies affecting motile cilia spans impaired mucociliary clearance in the respiratory system, laterality defects including heart malformations, infertility and hydrocephalus. Using linkage analysis and whole exome sequencing, we identified two recessive loss-of-function MNS1 mutations in five individuals from four consanguineous families: 1) a homozygous nonsense mutation p.Arg242* in four males with laterality defects and infertility and 2) a homozygous nonsense mutation p.Gln203* in one female with laterality defects and recurrent respiratory infections additionally carrying homozygous mutations in DNAH5. Consistent with the laterality defects observed in these individuals, we found Mns1 to be expressed in mouse embryonic ventral node. Immunofluorescence analysis further revealed that MNS1 localizes to the axonemes of respiratory cilia as well as sperm flagella in human. In-depth ultrastructural analyses confirmed a subtle outer dynein arm (ODA) defect in the axonemes of respiratory epithelial cells resembling findings reported in Mns1-deficient mice. Ultrastructural analyses in the female carrying combined mutations in MNS1 and DNAH5 indicated a role for MNS1 in the process of ODA docking (ODA-DC) in the distal respiratory axonemes. Furthermore, co-immunoprecipitation and yeast two hybrid analyses demonstrated that MNS1 dimerizes and interacts with the ODA docking complex component CCDC114. Overall, we demonstrate that MNS1 deficiency in humans causes laterality defects (situs inversus) and likely male infertility and that MNS1 plays a role in the ODA-DC assembly.

Successful Drug-eluting Stent Implantation in a Male Patient with Dextrocardia: A Case Report

Situs inversus with dextrocardia is a rare condition, with complete transposition of all the body organs, including the heart. Percutaneous coronary intervention (PCI) in these patients is technically difficult because of the mirror image of organs. Here, we describe a 56-year-old man with coronary heart disease with known situs inversus with dextrocardia and coronary percutaneous intervention was performed for stenosis in the right coronary artery. A drug eluting stent was implanted at this site successfully. This case suggested that the interventional management of such patients follows the same general rules as for non-dextrocardia patients, but the manipulation of the catheter and projection position choices need to be taken into consideration to obtain optimal benefits for the patient.

Comparing levocardia and dextrocardia in fetuses with heterotaxy syndrome: prenatal features, clinical significance and outcomes

Background

To investigate the differences in cardiovascular disease, extracardiac anomalies and outcomes between fetuses with levocardia and dextrocardia.

Methods

Clinical demographics, prenatal features, postnatal characteristics and the outcomes of fetuses with levocardia or dextrocardia were recorded and analyzed.

Results

Sixty-five fetuses with dextrocardia and thirty-eight fetuses with levocardia were enrolled. Right ventricle outlet obstruction, atrioventricular septal defect and intestinal malrotation were common in both groups. Univentricular physiology, transposition of the great arteries and esophageal atresia were more frequent in fetuses with levocardia, whereas abnormal pulmonary venous connection, double outlet of right ventricle, left ventricle outlet obstruction and brain abnormalities were more frequent in the dextrocardia group. The accuracy of evaluating cardiac malformations was high, but the sensitivity in assessing extracardiac abnormalities was low.

Conclusions

Although the disorders have certain overlapping features, there are several differences between fetuses with levocardia and dextrocardia. These findings might improve patient counseling and perinatal management.

Dextrocardia in Adults with Congenital Heart Disease

BACKGROUND/OBJECTIVES

Dextrocardia is rare in the general population, and may be associated with significant additional cardiac malformations. We aimed to identify the prevalence and patterns of additional cardiac defects, as well as the associated long-term morbidity and mortality, in adult patients with dextrocardia, in a specialised Adult Congenital Heart Disease (ACHD) service.

METHODS

A retrospective study of patients with dextrocardia managed by our tertiary ACHD service, since January 2000, was performed. Medical records were reviewed and the National Death Index was consulted to confirm survival status.

RESULTS

Of 3698 adults in our ACHD Service, 19 (0.5%) had dextrocardia. Mean follow-up duration was 7±7.5 years. The mean age at last review was 36.8±10.5 years (range 20-63 years). Situs was solitus in 14 (74%) and inversus in five (26%). Eleven patients (58%) had functional single ventricles, of whom five had atrioventricular (AV)-ventriculoarterial (VA) discordance and two had VA discordance only. Four patients with two ventricles had AV-VA discordance. All patients had at least one additional cardiac malformation. Fourteen patients (74%) required surgical intervention. Eleven patients (58%) underwent a Fontan-type operation. Five patients (26%) required ablation procedures for arrhythmia. One patient had infective endocarditis and two deaths occurred, both in patients who also had AV-VA discordance.

CONCLUSION

Dextrocardia remains a rare finding in adults, even in a highly select group of patients with known congenital heart disease. Those with associated congenital heart abnormalities are likely to have complex lesions, which may require multiple surgical and medical interventions. Despite this, our series demonstrated that patients surviving to adulthood and then managed in an ACHD centre may have good medium-term survival.

Laparoscopic and endoscopic cooperative surgery for gastrointestinal stromal tumor with complete situs inversus: report of a case

We herein report our experience of performing laparoscopic and endoscopic cooperative surgery for a gastrointestinal stromal tumor with complete situs inversus. A 78-year-old man was referred to our department for treatment of a gastric submucosal tumor. Based on chest X-ray and computed tomography (CT) findings, complete situs inversus was also diagnosed. Upper gastrointestinal endoscopy and imaging showed a 45-mm gastric submucosal tumor in the upper stomach near the esophagogastric junction. We performed local resection of the gastric submucosal tumor by laparoscopic and endoscopic cooperative surgery. Pathological examination revealed that the tumor was an intermediate-risk gastrointestinal stromal tumor, and the patient was discharged on postoperative day 12. The patient is still alive without recurrence or any complications 9 months after surgery.

Cardiac malposition (ectopia cordis) in a cat

OBJECTIVE

To describe a case of cardiac malposition in a cat, and the successful management of the anomaly.

CASE DESCRIPTION

A 2-year-old male neutered male British Shorthair cat weighing 7.58 kg was referred for bicavitary effusion. Ultrasonography and echocardiography demonstrated displacement of the heart into the abdomen through a diaphragmatic defect. Clinical signs of right-sided congestive heart failure were attributed to mechanical restriction of diastolic function by a constrictive segment of fibrous pericardium and to impaired venous return due to a kink in the caudal vena cava. Surgical repositioning of the heart into the thoracic cavity and a subtotal pericardectomy were performed, and the diaphragmatic defect was repaired. The patient recovered well postoperatively.

NEW OR UNIQUE INFORMATION PROVIDED

The diagnosis and management of cardiac malposition has not been previously described in cats. With timely diagnosis and surgical intervention, a favorable outcome is possible.

Symmetry breakage in the vertebrate embryo: when does it happen and how does it work?

Asymmetric development of the vertebrate embryo has fascinated embryologists for over a century. Much has been learned since the asymmetric Nodal signaling cascade in the left lateral plate mesoderm was detected, and began to be unraveled over the past decade or two. When and how symmetry is initially broken, however, has remained a matter of debate. Two essentially mutually exclusive models prevail. Cilia-driven leftward flow of extracellular fluids occurs in mammalian, fish and amphibian embryos. A great deal of experimental evidence indicates that this flow is indeed required for symmetry breaking. An alternative model has argued, however, that flow simply acts as an amplification step for early asymmetric cues generated by ion flux during the first cleavage divisions. In this review we critically evaluate the experimental basis of both models. Although a number of open questions persist, the available evidence is best compatible with flow-based symmetry breakage as the archetypical mode of symmetry breakage.

Diagnosis and outcome of pregnancies with prenatally diagnosed fetal dextrocardia

OBJECTIVE

To evaluate the incidence, associated cardiac and extracardiac malformations and clinical outcome of fetuses with dextrocardia.

METHOD

A retrospective review of 3556 fetal echocardiograms between 2000 and 2011 revealed 39 cases of dextrocardia. Dextrocardia was defined as right-sided positioning of the fetal heart. Prenatal and postnatal records of the fetuses were reviewed.

RESULTS

The incidence was 1.1%. Of the 39 fetuses, 22 were primary dextrocardia and 17 were dextroposition. Diaphragmatic hernia was the most common cause of dextroposition with the incidence of 76%. Of the fetuses with dextroposition 35.5% had a cardiac anomaly. The survival rate of dextroposition was 31.2% and none of the survivors had an associated cardiac anomaly. Primary fetal dextrocardia was most common with situs solitus (45.4%), followed by situs ambiguous (36.3%) and then situs inversus totalis (18.1%). Structural cardiac malformations were found in 100%, 80% and 25% of fetuses with situs ambiguous, solitus and inversus, respectively. Of the dextroposition, 47.6% terminated pregnancy, 14.2% resulted in intrauterine death, 9.5% died after birth, and 28.5% survived.

CONCLUSION

A wide spectrum of complex cardiac malformations are associated with fetal dextrocardia. Fetal echocardiography enables detection of complex cardiac anomalies so that parents can be appropriately counselled.

Cardiovascular manifestations of heterotaxy and related situs abnormalities assessed with CT angiography

Heterotaxy and situs abnormalities describe an abnormal arrangement of visceral organs in the thoracoabdominal cavity across the normal left-right axis of the body. It is associated with a high occurrence of congenital heart and abdominal defects, including anomalous pulmonary venous connections, systemic venous abnormalities, asplenia, and intestinal malrotation. Without proper diagnosis and surgical intervention, the prognosis of patients with heterotaxy syndrome and associated congenital defects is extremely poor. Complex intracardiac and extracardiac lesions are common in heterotaxy and can be difficult to assess by echocardiography. CT angiography (CTA) is a useful tool in this setting to accurately assess intracardiac and extracardiac abnormalities in this population for medical or surgical management. The intention of this pictorial essay is to review the most common cardiovascular defects involved with heterotaxy syndrome in addition to emphasizing the utility of CTA in the identification and classification of anomalies seen in these patients. This review briefly defines most common terminology used in situs abnormalities as well as presents CT images and 3-dimensional reconstructions of common anomalies associated with situs abnormalities. In summary, this review should prepare radiologists and pediatric cardiologists to describe heterotaxy and situs abnormalities in addition to recognizing the utility of CTA in these patients.

A unified model for left-right asymmetry? Comparison and synthesis of molecular models of embryonic laterality

Understanding how and when the left-right (LR) axis is first established is a fundamental question in developmental biology. A popular model is that the LR axis is established relatively late in embryogenesis, due to the movement of motile cilia and the resultant directed fluid flow during late gastrulation/early neurulation. Yet, a large body of evidence suggests that biophysical, molecular, and bioelectrical asymmetries exist much earlier in development, some as early as the first cell cleavage after fertilization. Alternative models of LR asymmetry have been proposed that accommodate these data, postulating that asymmetry is established due to a chiral cytoskeleton and/or the asymmetric segregation of chromatids. There are some similarities, and many differences, in how these various models postulate the origin and timing of symmetry breaking and amplification, and these events' linkage to the well-conserved subsequent asymmetric transcriptional cascades. This review examines experimental data that lend strong support to an early origin of LR asymmetry, yet are also consistent with later roles for cilia in the amplification of LR pathways. In this way, we propose that the various models of asymmetry can be unified: early events are needed to initiate LR asymmetry, and later events could be utilized by some species to maintain LR-biases. We also present an alternative hypothesis, which proposes that individual embryos stochastically choose one of several possible pathways with which to establish their LR axis. These two hypotheses are both tractable in appropriate model species; testing them to resolve open questions in the field of LR patterning will reveal interesting new biology of wide relevance to developmental, cell, and evolutionary biology.

A chick embryo with a yet unclassified type of cephalothoracopagus malformation and a hypothesis for explaining its genesis

Cephalothoracopagus embryos are conjoined twins, who share parts of their heads, necks and bodies. Our study aims at presenting a detailed morphological analysis of a cephalothoracopagus chick embryo of developmental stage 31. Because none of the existing theories can explain the genesis of the phenotype of this embryo, we also suggest a hypothesis, which explains it. Beside the cephalothoracopagus embryo, we investigated five control embryos. With the aid of the high-resolution episcopic microscopy (HREM) technique, we created digital volume data and three-dimensional (3D) computer models of the organs and arteries of the embryos. We used the 3D models for topological analysis and for measuring the diameters of the great intrathoracic arteries. The malformed embryo showed two body backs, each containing a notochord, spinal cord and dorsal aorta. The body backs continued into separated lower bodies. The embryo had a single, four-chambered heart, single respiratory tract and single upper alimentary tract. The topology of the pharyngeal arch arteries was normal, and the diameters of these arteries were similar to that of the control embryos. We classified the embryo we investigated as a yet unknown malformation and suggest a hypothesis explaining its genesis.

Twelve-lead electrocardiography in the young: physiologic and pathologic abnormalities

BACKGROUND/ OBJECTIVE: The purpose of the present study was to analyze the prevalence of physiologic and pathologic ECG abnormalities in a cohort of young conscripts that represents the whole young generation of today.

METHODS

ECGs of all Swiss citizens who underwent conscription for the army during a 29-month period were analyzed manually.

RESULTS

ECGs of 43,401 conscripts (mean age 19.2 ± 1.1 years) were analyzed; 158 conscripts were female. Incomplete right bundle branch block was found in 5870 (13.5%) and left anterior fascicular block in 360 (0.83%). First-degree AV block was present in 329 (0.8%) and Mobitz type I (Wenckebach) second-degree AV block in 3 (0.01%). Early repolarization was observed in 1035 (2.4%), T-wave inversion in 39 (0.09%), and minor T-wave changes in 182 (0.42%). Brugada-like abnormalities were observed in 6 (0.01%). None of the conscripts had atrial fibrillation or flutter.

CONCLUSION

ECG abnormalities can be found in a relatively large proportion of young individuals. Incomplete right bundle branch block, left fascicular block, and first-degree AV block are the most frequent findings. No conscript presented with atrial fibrillation or flutter.