Warden repair for superior sinus venosus atrial septal defect and anomalous pulmonary venous drainage in children: Anesthesia and transesophageal echocardiography perspectives.

Objective: Review of intraoperative anesthetic challenges and the role of transesophageal echocardiography in children with sinus venosus atrial septal defect and partial anomalous pulmonary venous drainage undergoing Warden repair. Design: A retrospective observational case series. Methodolgy: Pediatric patients who underwent Warden repair between October 2011-September 2015 were recruited. Their preoperative clinical details, anesthetic techniques, intraoperative TEE findings and postoperative events were recorded from the medical records. The categorical variables and the continuous variables were expressed as number (percentages) and mean ± SD respectively. Results: A total of 35 patients were operated for Warden repair during the study period. Anesthesia was induced with the aim to prevent any fall in pulmonary vascular resistance. The right internal jugular vein was cannulated under ultrasound guidance using a short length cannula to monitor right superior vena cava pressure. Intraoperative TEE revealed the drainage of PAPVC high into RSVC in 22 patients. Persistent LSVC was found in 9 patients. After repair, TEE imaging detected a high gradient at Warden anastomotic site in 5 patients and 3 of them required revision of surgery. Rerouted pulmonary veins required surgical correction in 2 patients in view of obstruction. None of them had pulmonary venous and SVC obstruction in the postoperative period. Conclusion: The primary aim of anesthesia is to avoid any fall in PVR. Right IJV cannulation can be beneficial. The intraoperative TEE can help in delineating the anatomy of lesion and detecting anastomotic site obstruction.

Upper terminal of the inferior vena cava and development of the heart atriums: a study using human embryos / 대한해부학회지

In the embryonic heart, the primitive atrium is considered to receive the bilateral sinus horns including the upper terminal of the inferior vena cava (IVC). To reveal topographical anatomy of the embryonic venous pole of the heart, we examined horizontal serial paraffin sections of 15 human embryos with crown-rump length 9-31 mm, corresponding to a gestational age of 6-7 weeks or Carnegie stage 14-16. The IVC was often fixed to the developing right pulmonary vein by a mesentery-like fibrous tissue. Rather than the terminal portion of the future superior vena cava, the IVC contributed to form a right-sided atrial lumen at the stage. The sinus venosus or its left horn communicated with the IVC in earlier specimens, but in later specimens, the left atrium extended caudally to separate the sinus and IVC. In contrast, the right atrium consistently extended far caudally, even below the sinus horn, along the IVC. A small (or large) attachment between the left (or right) atrium and IVC in adult hearts seemed to be derived from the left (or right) sinus valve. This hypothesis did not contradict with the incorporation theory of the sinus valves into the atrial wall. Variations in topographical anatomy around the IVC, especially of the sinus valves, might not always depend on the stages but partly in individual differences.

Anatomia comparativa da dura-máter de Sapajus libidinosus / Comparative anatomy of dura-mater of Sapajus libidinosus

O Sapajus libidinosus é um primata do novo mundo popularmente conhecido como macaco-prego, geograficamente distribuído por todo território sul-americano, possui características de inquietude e habilidade de manipulação de ferramentas para a obtenção de alimentos. Este estudo teve por objetivo descrever a morfologia dos seios da dura-máter de Sapajus libidinosus numa perspectiva comparativa. Foram utilizados um total de 3 animais adultos e machos oriundos da Universidade Federal de Goiás e fixados em solução aquosa de formaldeído 10%. No encéfalo de S. libidinosus, foi possível observar a fissura longitudinal, profunda e que divide o mesmo em dois hemisférios, esquerdo e direito. O lobo parietal e frontal apresenta-se relativamente lisoencefálico, mas com giros e sulcos bem definidos e no lobo occipital nota-se a predominância do aspecto lisencefálico. Nota-se a presença de 8 seios da dura-máter, que corresponde de modo geral às descrições para outros primatas como Pan, Papio e homem. Notamos a presença dos seios sagital dorsal, seio sagital ventral, seio transverso, seio reto, seio sigmóide, seio temporal e seio basilar, que são semelhantes a Pan, Papio e homem, a presença do seio parietal semelhante à Saimiri sciureus e a ausência do seio occipital, assim como em Macaca mullata. No macaco prego não foram observados os seios intracavernosos, seio esfenoparietal, seio petroso superior, seio petroso inferior, sendo estes descritos em Pan, Papio e Homem. Sendo assim, estes dados demonstram uma possível maior proximidade evolutiva entre Papio e Pan em relação ao homem do que o macaco Sapajus.

Sapajus libidinosus is a new World primate commonly known as capuchin monkey, geographically distributed throughout South America, has characteristics of restlessness and ability to manipulate tools to obtain food. This study aimed to describe the morphology of the dural sinuses of S. libidinosus through a comparative perspective. We used 3 adult male from the Federal University of Goiás, Brazil, fixed in aqueous 10% formaldehyde. The longitudinal fissure in the brain extends deeply and divides the organ into two left right hemispheres, The frontal and parietal lobe presents relatively smooth surface, but with well-defined gyri and sulci. In the occipital lobe, however, smooth surface aspect prevails. We observed eight sinuses of the dura mater, sagittal dorsal, ventral sagittal, transverse, straight, sigmoid, basilar and temporal which corresponds generally to the descriptions of other primates as Pan, Papio and man. Furthermore, parietal sinus similar to Saimiri sciureus and absence of sinus occipital, as in Macaca mullata, were also recorded. In the capuchin monkey, intracavernous, sphenoparietal, superior petrosal and inferior petrosal sinuses, which are described in Pan, Papio and Man, were absent. Taken together, these data point to a possible grater evolutionary proximity to man of Papio and Pan as compared to Cebus.

Characteristics and Outcomes of Atrial Tachycardia Originating from the Sinus Venosus during Catheter Ablation of Atrial Fibrillation

BACKGROUND AND OBJECTIVES: The sinus venosus (SV) is not a well known source of atrial tachycardia (AT), but it can harbor AT during catheter ablation of atrial fibrillation (AF). SUBJECTS AND METHODS: A total of 1223 patients who underwent catheter ablation for AF were reviewed. Electrophysiological and electrocardiographic characteristics and outcomes after catheter ablation of AT originating from the SV were investigated. RESULTS: Ten patients (0.82%) demonstrated AT from the SV (7 males, 53.9+/-16.0 years, 6 persistent) during ablation of AF. The mean cycle length was 281+/-73 ms. After pulmonary vein isolation and left atrial ablation, AF converted to AT from the SV during right atrial ablation in 2 patients, by rapid atrial pacing after AF termination in 7 patients, and during isoproterenol infusion in 1 patient. Positive P-waves in inferior leads were shown in most patients (90%). The activation sequence of AT was from proximal to distal in the superior vena cava and high to low in the right atrium, which was similar to that of AT from crista terminalis. Fragmented double potentials were recorded during sinus, and a second discrete potential preceded the onset of P wave by 80+/-37 ms during AT. Using 4.4+/-2.7 radiofrequency focal applications, ATs were terminated and became no longer inducible in all. After ablation procedure, two patients showed transient right phrenic nerve palsy. After 19.9+/-14.8 months, all but 1 patient were free of atrial tachyarrhythmia without complications. CONCLUSION: The AT which develops during AF ablation is rarely originated from SV, and its electrophysiologic characteristics may be helpful in guiding effective focal ablation.

Macroscopic aspects of Saimiri sciureus dura mater / Aspectos macroscópicos da dura mater de Saimiri sciureus

Saimiri sciureus is a small New World primate (NHP) commonly called macaco-de-cheiro that inhabits the tropical forests of the Amazon basin. Anatomical features are not well studied in most primates, and the encephalic morphology and related structures are still quite unknown. Comparative anatomy of the meninges in South American primates is still scarce. Dura mater, arachnoid and pia mater are a group of stratified layers that surrounds and promotes protection to the medulla spinalis. This study aimed to shed light on the anatomy of dura mater in Samiri sciureus in order to contribute to the neuroscience in primates. We investigated three young females and two males of S. sciureus. Specimens were fixed through perfusion with a 10 percent formaldehyde aqueous solution. In S. sciureus encephalus few gyrus and circunvolutions, and a very delicate system consisting of eight sinus venosus was found between the dura mater layers. Based on our findings, we can conclude that the Saimiri sciureus dura mater is quite similar to other mammals, however we detected a new sinus venosus formation at the level of parietal bone, named sinus parietalis, what appears to be its first description.

Saimiri sciureus, com nome comum de macaco-de-cheiro, é um pequeno primata do Novo Mundo (PNM) que habita as florestas tropicais da Bacia Amazônica. Os detalhes anatômicos de primatas são pouco conhecidos e a anatomia comparada de animais selvagens da América do Sul é escassa, mais especificamente, sobre as meninges de PNM. Meninges pertencem a um sistema de membrana responsável por envolver e proteger o Sistema Nervoso Central; consiste em três membranas: dura mater, aracnoide e pia mater. Este estudo objetivou a elucidação do comportamento anatômico da dura mater de S. sciureus com o intuito de contribuir para a área de neurociências em primatas. Foram investigados três fêmeas e dois machos jovnes de S. sciureus. Os espécimes de meninges foram fixados por perfusão usando solução aquosa 10 por cento de formaldeído. O encéfalo de S. sciureus demonstrou um número baixo de giros e circunvoluções, e um sistema delicado de oito seios venosos foi verificado entre as camadas da dura mater. Baseados em nossos achados podemos concluir que a dura mater de S. sciureus é similar aos de outros mamíferos, no entanto, apresenta a formação de um novo seio venoso em nível ao osso parietal, sendo denominado de seio parietal. Isto parece ser a primeira descrição deste seio.

Role of intraoperative echocardiography in surgical correction of the superior sinus venosus atrial septal defect.

Superior type of sinus venosus atrial septal defect (SVASD) is invariably associated with the unroofing of right upper pulmonary vein (RUPV). Warden procedure and pericardial patch repair with rerouting of the RUPV are commonly performed operations for the superior SVASD. Both operations involve the risk of obstruction to the flow of superior vena cava or rerouted pulmonary vein in the postoperative period. The sinus venosus defects are well visualized on the transesophageal echocardiography (TEE) because of the proximity of the TEE probe to these structures. We are reporting two cases operated for the superior SVASD with unroofed RUPV, highlighting the intraoperative echocardiographic features before and after the surgery.

Early development of the sinus venosus and the cardiac conduction system in human embryonic heart / 解剖学报

Objective To investigate the early development of the sinus venosus and the cardiac conduction system (CCS) of human embryonic hearts. Methods Serial transverse sections of 29 human embryonic hearts from Carnegie stage 10 to Carnegie stage 16 (C10-C16) were stained immunohistochemically with antibodies against α-smooth muscle actin(α-SMA),α-sarcomeric actin(α-SCA) and desmin ( DES ). Results During C12 and C13, the sinus venosus formed by confluence of systematic veins at the caudal end of the pericardial cavity could be recognized in the mesenchyme of primitive transverse septum. The mesenchymal cells of the sinus venosus gradually differentiated into α-SCA positive cardiocyocytes. At C14, the sinus venosus was within the pericardial cavity due to expansion of the pericardial cavity and incorporated into the right atrium. Differentiation of DES positive conductive cardiomyocyte was initiated in the right wall of atrio-ventricular canal of C10 embryonic heart and with the development, extended towards the myocardium of the interventricular sulcus to form His bundle, left and right bundle branches as well as the ventricular trabecular myocardium. In the atium, the strong expression of DES was first detected in the dorsal wall of C11 atrium. At C13, unique myocardial band showing α-SCA, α-SMA and DES expression in the left dorsal wall of the sinus venosus were found to be continuous with the basal wall of left atium and the dorsal wall of the atrio-ventricular canal, this band might be related to the development of conduction system from sinoatrial node to atrio-ventricular canal. During C14 to C16, primary conduction pathway of atria with strong DES expression was formed that extended from sinoatrial node along venous valves, DES positive myocardium in the dorsal and ventral walls of the atria to the right atrio-ventricular canal, respectively. Conclusions The mesenchyme of the primitive transverse septum is the heart forming field of human embryos responsible for formation of sinus venosus myocardium, cardiomyocytes are differentiated from mesenchymal cells in the primitive transverse septum and progressively added to the venous pole of the heart tube to form myocardial sinus venosus. The differentiation of CCS of the early human embryo initiates in the atrio-ventricular canal and develops gradually towards the arterial and venous poles of the heart tube. By C16, DES positive embryonic CCS can be clearly recognized morphologically.

Developmental Morphology of the Atrial Venous Component in the iv/iv Mouse

PURPOSE: Developmental processes of atria in embryos or fetuses of the iv/iv mouse were studied to find the differences between right and left atrial chambers and to identify the characteristics of atrial isomerism in the abnormal laterality syndrome. METHODS: Seventy-three embryos from SI/Col iv/iv mice (Jackson's laboratory, USA) or fetuses at the 10th-13th day were used. They were examined using stereomicroscope, scanning electronmicroscope, serial section, and thick slicing in the agar block. RESULTS: Thirty-three cases (45%) had usual arrangement but 40 cases (55%) had abnormal laterality, which included 29 cases of mirror-imaged appendages, seven with left isomerism, two with right isomerism and two with undeterminate appendages. Embryonic right atrium was initially composed of a large conspicuous appendage, which was a thin walled diverticulum and small venous component. As development progressed, venous valves and septum spurium became prominent. The embryonic left atrium was composed of the less conspicuous appendage but the major part of embryonic left atrium was the primitive atrium merging into the atrioventricular canal. The atrial chamber in the right isomerism had a bilateral big appendage and small venous component and the atrioventricular orifice was located in the center of the atrial outlet. Atrial chambers in the left isomerism had a bilateral small appendage and the central venous component was wide. CONCLUSION: The atrial morphology is the best marker in the determination of the atrial laterality. The appendages in hearts with isomerism had bilateral symmetrical arrangement of the appendages.

Developmental Morphology of the Atrial Venous Component in the iv/iv Mouse

PURPOSE: Developmental processes of atria in embryos or fetuses of the iv/iv mouse were studied to find the differences between right and left atrial chambers and to identify the characteristics of atrial isomerism in the abnormal laterality syndrome. METHODS: Seventy-three embryos from SI/Col iv/iv mice (Jackson's laboratory, USA) or fetuses at the 10th-13th day were used. They were examined using stereomicroscope, scanning electronmicroscope, serial section, and thick slicing in the agar block. RESULTS: Thirty-three cases (45%) had usual arrangement but 40 cases (55%) had abnormal laterality, which included 29 cases of mirror-imaged appendages, seven with left isomerism, two with right isomerism and two with undeterminate appendages. Embryonic right atrium was initially composed of a large conspicuous appendage, which was a thin walled diverticulum and small venous component. As development progressed, venous valves and septum spurium became prominent. The embryonic left atrium was composed of the less conspicuous appendage but the major part of embryonic left atrium was the primitive atrium merging into the atrioventricular canal. The atrial chamber in the right isomerism had a bilateral big appendage and small venous component and the atrioventricular orifice was located in the center of the atrial outlet. Atrial chambers in the left isomerism had a bilateral small appendage and the central venous component was wide. CONCLUSION: The atrial morphology is the best marker in the determination of the atrial laterality. The appendages in hearts with isomerism had bilateral symmetrical arrangement of the appendages.