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1.
Neonatal Netw ; 38(2): 98-106, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31470372

RESUMO

BACKGROUND: VACTERL association is a sporadic, nonrandom series of congenital malformations diagnosed by the presence of three or more of the following: vertebral malformations, anal atresia, cardiac defects, tracheoesophageal fistula, renal malformations, and limb malformations. Situs inversus totalis (SIT) and esophageal malformations are rarely associated. This is the first reported case in North America of VACTERL association with SIT. IMPLICATIONS FOR PRACTICE: Respiratory distress in the term infant requires full exploration of all possible causes because the etiology may be far more complex than routinely diagnosed respiratory distress syndrome. This particular case demonstrates physical exam findings and supportive imaging that would be observed in infants with VACTERL association and with SIT, highlighting considerations when, rarely, both occur simultaneously.


Assuntos
Canal Anal/anormalidades , Esôfago/anormalidades , Cardiopatias Congênitas , Rim/anormalidades , Deformidades Congênitas dos Membros , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Situs Inversus , Coluna Vertebral/anormalidades , Traqueia/anormalidades , Assistência ao Convalescente/métodos , Canal Anal/fisiopatologia , Diagnóstico Diferencial , Esôfago/fisiopatologia , Feminino , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/terapia , Humanos , Recém-Nascido , Rim/fisiopatologia , Deformidades Congênitas dos Membros/complicações , Deformidades Congênitas dos Membros/diagnóstico , Deformidades Congênitas dos Membros/fisiopatologia , Deformidades Congênitas dos Membros/terapia , Triagem Neonatal/métodos , Administração dos Cuidados ao Paciente/métodos , Exame Físico/métodos , Radiografia Abdominal/métodos , Radiografia Torácica/métodos , Situs Inversus/complicações , Situs Inversus/diagnóstico , Situs Inversus/fisiopatologia , Situs Inversus/terapia , Coluna Vertebral/fisiopatologia , Traqueia/fisiopatologia , Doenças do Nervo Vestibulococlear/congênito , Doenças do Nervo Vestibulococlear/diagnóstico
2.
BMJ Case Rep ; 12(7)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31345831

RESUMO

Kartagener syndrome is a rare autosomal recessive condition. Approximately 25% of those with situs inversus totalis suffer the syndrome. With the rising overall number and indications for bariatric surgery, this condition will be increasingly recognised. We present a case of a 25-year-old woman with SIT and Kartagener syndrome who underwent a laparoscopic sleeve gastrectomy. As with all bariatric surgery, a multidisciplinary team approach was important in managing such a case. There were considerable cognitive challenges for the surgical team both preoperatively and during the procedure. The patient tolerated the operation well and was discharged 2 days after the surgery. At 12-months follow-up, the patient had achieved 125% excess weight loss. This case illustrates that an experienced surgeon can safely perform a laparoscopic sleeve gastrectomy on a patient with situs inversus totalis.


Assuntos
Gastrectomia , Síndrome de Kartagener/cirurgia , Laparoscopia , Obesidade Mórbida/cirurgia , Situs Inversus/cirurgia , Redução de Peso/fisiologia , Adulto , Feminino , Humanos , Síndrome de Kartagener/complicações , Síndrome de Kartagener/fisiopatologia , Obesidade Mórbida/complicações , Obesidade Mórbida/fisiopatologia , Situs Inversus/complicações , Situs Inversus/fisiopatologia , Resultado do Tratamento
3.
Cortex ; 106: 12-25, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29864592

RESUMO

Most humans show typical brain functional specialization with language and praxis favoring left hemisphere lateralization and spatial attention and face recognition showing right hemisphere dominance. Lateralization of these cognitive functions was investigated using fMRI in participants with complete visceral reversal and matched control participants. While most participants revealed typical brain organization, atypical functional segregation was significantly more frequent in participants with visceral reversal. Interestingly, some left handers maintained typical functional segregation but showed complete reversal of all cognitive functions regardless of visceral organization. Cognitive performance, as measured with a neuropsychological test battery, was significantly predicted by the degree of atypical functional segregation of praxis and spatial attention. Increased deviation from typical functional segregation paired with lower cognitive performance. The findings suggest that typical functional segregation reflects an optimal evolutionary solution with deviations being associated with reduced cognitive performance.


Assuntos
Encéfalo/fisiopatologia , Lateralidade Funcional/fisiologia , Idioma , Situs Inversus/fisiopatologia , Adolescente , Adulto , Idoso , Mapeamento Encefálico/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Echocardiography ; 34(11): 1733-1735, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28929519

RESUMO

We herein describe the previously unreported combination of partial anomalous venous connection to the superior vena cava combined with situs inversus totalis. Following peripheral contrast injection, bubbles appeared initially in the left atrium allowing the diagnosis of a supra-atrial connection to be made using transthoracic echocardiography, but this timing was not anymore reproduced during transesophageal echocardiography performed minutes later. Cardiac computed tomography allowed the final diagnosis to be made. This case emphasizes the importance of performing bubble studies both during transesophageal and transthoracic echocardiography.


Assuntos
Ecocardiografia/métodos , Veias Pulmonares/diagnóstico por imagem , Situs Inversus/diagnóstico por imagem , Veia Cava Superior/diagnóstico por imagem , Ecocardiografia Transesofagiana/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/fisiopatologia , Situs Inversus/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Veia Cava Superior/fisiopatologia
6.
Medicine (Baltimore) ; 96(39): e8209, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28953685

RESUMO

RATIONALE: Situs inversus totalis (SIT) is a rare congenital anomaly characterized by complete inversion of the abdominal and thoracic organs, and often involves multiple genetic mutations. The most suitable surgical technique for patients with multiple vessel and organ variations as well as SIT remains unclear. Furthermore, there has been insufficient clinical evidence that demonstrates which surgical techniques achieve the best outcomes. Finally, the standard of care has not yet been determined. We present the case of a 60-year-old man with SIT, who was diagnosed with moderately and poorly differentiated adenocarcinoma at the gastroesophageal junction. We further describe the advantage of using robotic-assisted laparoscopic surgery in patients with this anomaly. PATIENT CONCERNS: A 60-year-old man complained of pain in his upper abdomen for 3 months. Physical examination revealed an apex beat in the right fifth intercostal space, and vascular anomalies were noted on abdominal angiographic computed tomography. DIAGNOSES: Moderately and poorly differentiated adenocarcinoma at the gastroesophageal junction with SIT. INTERVENTIONS: Robot-assisted total gastrectomy with D2 lymph node dissection and hand-sewn Roux-en-Y anastomosis was performed. OUTCOMES: The postoperative course was uneventful, and the patient was discharged on the seventh postoperative day. LESSONS: Robotic surgery for gastric cancer is a safe and feasible alternative to laparoscopic surgery and it can be successfully used to treat gastric cancer in patients with SIT with multiple anatomic variations. As exemplified by our case, SIT might be accompanied by multiple anatomic variations. Detailed preoperative detailed imaging of the blood vessels and gastrointestinal tract is useful in these patients.


Assuntos
Adenocarcinoma in Situ , Junção Esofagogástrica/patologia , Gastrectomia/métodos , Cuidados Pré-Operatórios/métodos , Situs Inversus , Neoplasias Gástricas , Adenocarcinoma in Situ/patologia , Adenocarcinoma in Situ/fisiopatologia , Adenocarcinoma in Situ/cirurgia , Angiografia por Tomografia Computadorizada/métodos , Anormalidades do Sistema Digestório/diagnóstico , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Robóticos/métodos , Situs Inversus/diagnóstico , Situs Inversus/fisiopatologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/fisiopatologia , Neoplasias Gástricas/cirurgia , Resultado do Tratamento , Malformações Vasculares/diagnóstico
7.
Brain Lang ; 174: 9-15, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28709112

RESUMO

Situs inversus totalis is a rare condition where the visceral organs are organized as a mirror image of default organ position. In this study we picture the co-development between brain and visceral organs in a case of situs inversus totalis from a fetal stage to adolescence and compare our findings to an age-, gender-, and education-matched control with normal position of thoracic and abdominal organs. We show that in this case of situs inversus, functional and structural brain lateralization do not coincide with visceral organ situs. Furthermore, cognitive development in situs inversus is normal. To our knowledge, this is the first report of antenatal cerebral origins of structural and functional brain asymmetry in a case of situs inversus totalis.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Lateralidade Funcional , Idioma , Situs Inversus/fisiopatologia , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Cognição/fisiologia , Alemanha , Humanos , Lactente , Recém-Nascido , Masculino
8.
Rev Neurol ; 64(11): 509-513, 2017 Jun 01.
Artigo em Espanhol | MEDLINE | ID: mdl-28555457

RESUMO

INTRODUCTION: Situs inversus of the optic nerve is a congenital anomaly characterised by the emergence of the vessels in the retina towards the nose rather than in a temporal direction. It is caused by an anomalous insertion of the optic stalks into the optic vesicle that gives rise to dysversion of the head of the optic nerve. It is not an isolated condition and usually appears jointly with tilted disc syndrome and in patients with myopia. It is characterised by the presence of inferior conus atrophy, deficiencies in the temporal visual field, refraction defects and ambliopy. CASE REPORT: A 22 years-old female who attended an ophthalmological examination due to severe frontal headaches accompanied by halos and loss of sharpness in her sight. From the results of the ophthalmetric and ophthalmological examination she was diagnosed as suffering from a condition consistent with this congenital anatomical anomaly. CONCLUSIONS: Situs inversus of the optic nerve is a rare condition that may appear in isolation or accompanied by other pathologies. Application of the visual field test and new diagnostic techniques, such as optical coherence tomography, facilitates the differential diagnosis of this situation. Its prevalence remains unknown, as it is not included in the register of rare diseases. Moreover, the scant number of patients studied and the scarce literature on this anomaly do not allow us to know whether the defects it causes develop over time. It would therefore be important to perform an ophthalmological follow-up of patients with situs inversus of the optic nerve.


TITLE: Situs inversus del nervio optico. A proposito de un caso.Introduccion. El situs inversus del nervio optico es una anomalia congenita caracterizada por la emergencia de los vasos de la retina en direccion nasal en lugar de temporal. Es causado por una anomala insercion del tallo optico en la vesicula optica que da lugar a la variacion de disposicion de la cabeza del nervio optico. No es una condicion aislada y suele aparecer junto con el sindrome del disco inclinado y en pacientes con miopia. Se caracteriza por la presencia de un cono de atrofia inferior, defectos en el campo visual temporal, defectos de refraccion y ambliopia. Caso clinico. Mujer de 22 años, que acude a revision oftalmologica por presentar fuertes cefaleas frontales acompañadas de halos y perdida de nitidez en la vision. Tras un examen optometrico y oftalmologico se llega al juicio clinico de que padece un cuadro compatible con esta anomalia anatomica congenita. Conclusiones. El situs inversus del nervio optico es una condicion rara que puede aparecer aislada o acompañada de otras patologias. La aplicacion de la campimetria y de nuevas tecnicas diagnosticas, como la tomografia de coherencia optica, facilita el diagnostico diferencial de esta situacion. No se conoce su prevalencia, pues no se encuentra en el registro de las enfermedades raras. Ademas, el escaso numero de pacientes estudiados y la exigua bibliografia existente sobre esta anomalia no permiten conocer si los defectos causados progresan en el tiempo, por lo que seria importante realizar un seguimiento oftalmologico de los pacientes con situs inversus del nervio optico.


Assuntos
Nervo Óptico/anormalidades , Situs Inversus , Feminino , Transtornos da Cefaleia Secundários/etiologia , Humanos , Situs Inversus/patologia , Situs Inversus/fisiopatologia , Tomografia de Coerência Óptica , Transtornos da Visão/etiologia , Testes de Campo Visual , Adulto Jovem
10.
Twin Res Hum Genet ; 20(1): 90-95, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28105968

RESUMO

The presence of situs inversus totalis (full reversal of internal organs) in twins is briefly reviewed. Information gathered from 35-year-old monozygotic (MZ) female twin pair discordant for this condition is presented. This is followed by summaries of research on the frequency of trisomy 21 (Down syndrome) in twins, the first case of MZ twin concordance for bilateral coronoid hyperplasia, prenatal hormonal effects in mixed-sex non-human primate litters, and links between insurance mandates and twinning following in vitro fertilization. The final section of this article describes twin-related events reported in the news, namely, the first recorded birth of identical twin puppies; the 100th birthday celebration of a pair of fraternal female twins, the passing of an award-winning identical twin production designer, and the first running of the New York City Marathon by a set of quadruplets.


Assuntos
Primatas/fisiologia , Situs Inversus/fisiopatologia , Estudos em Gêmeos como Assunto/tendências , Animais , Doenças em Gêmeos , Fertilização In Vitro , Humanos , Primatas/genética , Situs Inversus/genética , Gêmeos Dizigóticos , Gêmeos Monozigóticos/genética
11.
Univ. med ; 58(1)2017. ilus, tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-996109

RESUMO

El síndrome de Kartagener es una enfermedad autosómica recesiva poco frecuente (uno de cada 32.000 nacimientos), caracterizada por la tríada de bronquiectasias, sinusitis crónica y situs tnversus. El artículo presenta el caso de un hombre de veinticuatro años de edad con dicha enfermedad, a partir del cual se revisa su fisiopatología, las estrategias diagnósticas y terapéuticas y su pronóstico.


Kartagener syndrome us a rare autosomal recessive disease (one ¿n every 32,000 births), oharactenzed by a triad of bronchiectasis, chroníc sinusitis and situs mversus. We present the case of a 24'veai'old male with this disease and we review the pathophysiology, prognosis as well as the main diagnostic and therapeutic strategies.


Assuntos
Situs Inversus/fisiopatologia , Síndrome de Kartagener/diagnóstico , Síndrome de Kartagener/fisiopatologia
12.
Asian Cardiovasc Thorac Ann ; 24(2): 178-80, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25249659

RESUMO

Extracardiac total cavopulmonary connection between the inferior vena cava and right pulmonary artery has become the most popular Fontan modification nowadays, yielding good results. However, certain situs anomalies along with systemic venous drainage variations give rise to an issue about the best way for extracardiac conduit routing. Three cases of apicocaval juxtaposition are described. The situs was inversus with the apex and inferior vena cava on the same side (left), whereas the superior vena cava (Glenn) was located on the right in all cases. The literature is revisited and technical options are discussed. Surgery was carried out with excellent short- and midterm results.


Assuntos
Anormalidades Múltiplas , Técnica de Fontan/métodos , Cardiopatias Congênitas/cirurgia , Artéria Pulmonar/cirurgia , Situs Inversus/complicações , Veia Cava Inferior/cirurgia , Criança , Pré-Escolar , Circulação Coronária , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/fisiopatologia , Humanos , Masculino , Artéria Pulmonar/fisiopatologia , Circulação Pulmonar , Situs Inversus/fisiopatologia , Resultado do Tratamento , Veia Cava Inferior/anormalidades , Veia Cava Inferior/fisiopatologia
13.
J Med Case Rep ; 9: 222, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26411880

RESUMO

INTRODUCTION: Dextrocardia with situs inversus is a rare congenital disease. In patients with this condition, the heart is presented as a mirror image of itself with its apex pointing to the right. The pulmonary and abdominal anatomies are reversed. Dextrocardia with situs inversus occurs at birth but its diagnosis may be in adulthood. This case advances knowledge by graphically describing the unusual electrocardiographic features of dextrocardia in a young adult. CASE PRESENTATION: We report a case of a 22-year-old Nigerian man of Yoruba ethnicity who presented himself for preadmission medical test. He had a standard 12-lead electrocardiogram which revealed uncommon features: inversion of P waves in leads I, aVL and aVR; dominantly negative QRS waves in leads I, V1 to V6; reverse R wave progression in chest leads; low voltage in V4 to V6; extreme QRS axis; flattened T waves in V4 to V6 and aVR; and inverted T waves in lead I and aVL. An electrocardiogram diagnosis of dextrocardia was made. The differential diagnosis considered was right ventricular hypertrophy. A cardiovascular examination showed pulse rate of 70 beats per minute, blood pressure of 119/62mmHg, visible cardiac impulse at right precordium, apex beat was located at his fifth right intercostal space mid-clavicular line. A chest X-ray (posterior anterior view) including upper abdomen showed dextrocardia; his aortic arch was located on the right. His stomach bubble was located below his right hemidiaphragm. His trachea was slightly deviated to the left. The findings in his lung fields were not remarkable. Abdominopelvic ultrasonography showed that right-sided intra-abdominal organs (liver, gallbladder) were located on the left while left-sided organs (stomach, spleen) were located on the right. His abdominal aorta was on the right while his inferior vena cava was located on the left. A diagnosis of dextrocardia with situs inversus was made ultrasonographically. CONCLUSIONS: A properly interpreted electrocardiogram was useful in suspecting the diagnosis of dextrocardia with situs inversus. So, an analysis of a relatively simple and non-invasive diagnostic tool such as an electrocardiogram allows for suspicion of a cardiovascular anomaly in a setting of scarce diagnostic resources.


Assuntos
Abdome/diagnóstico por imagem , Dextrocardia/diagnóstico , Eletrocardiografia , Situs Inversus/diagnóstico , Vísceras/diagnóstico por imagem , População Negra , Cardiomegalia/diagnóstico , Dextrocardia/fisiopatologia , Diagnóstico Diferencial , Humanos , Achados Incidentais , Masculino , Nigéria , Situs Inversus/fisiopatologia , Ultrassonografia , Adulto Jovem
15.
Proc Natl Acad Sci U S A ; 112(4): 1208-13, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25583500

RESUMO

Identifying potentially unique features of the human cerebral cortex is a first step to understanding how evolution has shaped the brain in our species. By analyzing MR images obtained from 177 humans and 73 chimpanzees, we observed a human-specific asymmetry in the superior temporal sulcus at the heart of the communication regions and which we have named the "superior temporal asymmetrical pit" (STAP). This 45-mm-long segment ventral to Heschl's gyrus is deeper in the right hemisphere than in the left in 95% of typical human subjects, from infanthood till adulthood, and is present, irrespective of handedness, language lateralization, and sex although it is greater in males than in females. The STAP also is seen in several groups of atypical subjects including persons with situs inversus, autistic spectrum disorder, Turner syndrome, and corpus callosum agenesis. It is explained in part by the larger number of sulcal interruptions in the left than in the right hemisphere. Its early presence in the infants of this study as well as in fetuses and premature infants suggests a strong genetic influence. Because this asymmetry is barely visible in chimpanzees, we recommend the STAP region during midgestation as an important phenotype to investigate asymmetrical variations of gene expression among the primate lineage. This genetic target may provide important insights regarding the evolution of the crucial cognitive abilities sustained by this sulcus in our species, namely communication and social cognition.


Assuntos
Agenesia do Corpo Caloso , Transtornos Globais do Desenvolvimento Infantil , Cognição , Situs Inversus , Lobo Temporal , Síndrome de Turner , Adulto , Agenesia do Corpo Caloso/diagnóstico por imagem , Agenesia do Corpo Caloso/fisiopatologia , Animais , Criança , Transtornos Globais do Desenvolvimento Infantil/diagnóstico por imagem , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Pan troglodytes , Radiografia , Situs Inversus/diagnóstico por imagem , Situs Inversus/fisiopatologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiopatologia , Síndrome de Turner/diagnóstico por imagem , Síndrome de Turner/fisiopatologia
16.
Am J Physiol Heart Circ Physiol ; 308(5): H416-23, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25527777

RESUMO

Situs inversus totalis (SIT) is characterized by complete mirroring of gross cardiac anatomy and position combined with an incompletely mirrored myofiber arrangement, being normal at the apex but inverted at the base of the left ventricle (LV). This study relates myocardial structure to mechanical function by analyzing and comparing myocardial deformation patterns of normal and SIT subjects, focusing especially on circumferential-radial shear. In nine control and nine SIT normotensive human subjects, myocardial deformation was assessed from magnetic resonance tagging (MRT) image sequences of five LV short-axis slices. During ejection, no significant difference in either circumferential shortening (εcc) or its axial gradient (Δεcc) is found between corresponding LV levels in control and SIT hearts. Circumferential-radial shear (εcr) has a clear linear trend from apex-to-base in controls, while in SIT it hovers close to zero at all levels. Torsion as well as axial change in εcr (Δεcr) is as in controls in apical sections of SIT hearts but deviates significantly towards the base, changing sign close to the LV equator. Interindividual variability in torsion and Δεcr values is higher in SIT than in controls. Apex-to-base trends of torsion and Δεcr in SIT, changing sign near the LV equator, further substantiate a structural transition in myofiber arrangement close to the LV equator itself. Invariance of εcc and Δεcc patterns between controls and SIT subjects shows that normal LV pump function is achieved in SIT despite partial mirroring of myocardial structure leading to torsional and shear patterns that are far from normality.


Assuntos
Ventrículos do Coração/fisiopatologia , Contração Miocárdica , Resistência ao Cisalhamento , Situs Inversus/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Feminino , Ventrículos do Coração/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Miócitos Cardíacos/fisiologia , Situs Inversus/patologia , Torção Mecânica
17.
Tex Heart Inst J ; 40(4): 481-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24082385

RESUMO

Tetralogy of Fallot is one of the most frequently diagnosed congenital cardiac abnormalities; however, its association with dextrocardia and situs inversus is reported only rarely. We report a case of these findings in a 7-year-old boy, describe the patient's postoperative course, and review the medical literature relevant to these combined conditions.


Assuntos
Anormalidades Múltiplas , Dextrocardia/complicações , Situs Inversus/complicações , Tetralogia de Fallot/complicações , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Criança , Dextrocardia/diagnóstico , Dextrocardia/fisiopatologia , Ecocardiografia , Eletrocardiografia , Hemodinâmica , Humanos , Masculino , Situs Inversus/diagnóstico , Situs Inversus/fisiopatologia , Tetralogia de Fallot/diagnóstico , Tetralogia de Fallot/fisiopatologia , Tetralogia de Fallot/cirurgia , Resultado do Tratamento
19.
PLoS Comput Biol ; 8(7): e1002611, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22844239

RESUMO

The left ventricle (LV) of mammals with Situs Solitus (SS, normal organ arrangement) displays hardly any interindividual variation in myofiber pattern and experimentally determined torsion. SS LV myofiber pattern has been suggested to result from adaptive myofiber reorientation, in turn leading to efficient pump and myofiber function. Limited data from the Situs Inversus Totalis (SIT, a complete mirror image of organ anatomy and position) LV demonstrated an essential different myofiber pattern, being normal at the apex but mirrored at the base. Considerable differences in torsion patterns in between human SIT LVs even suggest variation in myofiber pattern among SIT LVs themselves. We addressed whether different myofiber patterns in the SIT LV can be predicted by adaptive myofiber reorientation and whether they yield similar pump and myofiber function as in the SS LV. With a mathematical model of LV mechanics including shear induced myofiber reorientation, we predicted myofiber patterns of one SS and three different SIT LVs. Initial conditions for SIT were based on scarce information on the helix angle. The transverse angle was set to zero. During reorientation, a non-zero transverse angle developed, pump function increased, and myofiber function increased and became more homogeneous. Three continuous SIT structures emerged with a different location of transition between normal and mirrored myofiber orientation pattern. Predicted SIT torsion patterns matched experimentally determined ones. Pump and myofiber function in SIT and SS LVs are similar, despite essential differences in myocardial structure. SS and SIT LV structure and function may originate from same processes of adaptive myofiber reorientation.


Assuntos
Modelos Cardiovasculares , Miofibrilas/fisiologia , Situs Inversus/fisiopatologia , Biologia Computacional , Coração/fisiologia , Ventrículos do Coração/fisiopatologia , Humanos , Miocárdio/citologia , Anormalidade Torcional/fisiopatologia , Função Ventricular/fisiologia
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