Search

In fetal aortic stenosis (AS), it remains challenging to predict left ventricular development over the course of pregnancy. Myocardial organization, differentiation and fibrosis could be potential biomarkers relevant for biventricular outcome. We present four cases of fetal AS with varying degrees of severity and associate myocardial deformation on fetal ultrasound with postmortem histopathological characteristics. During routine fetal echocardiography, speckle tracking recordings of the cardiac four-chamber view were performed to assess myocardial strain as parameter for myocardial deformation. After pregnancy termination, postmortem cardiac specimens were examined using immunohistochemical labeling (IHC) of key markers for myocardial organization, differentiation and fibrosis and compared to normal fetal hearts. Two cases with critical AS presented extremely decreased left ventricular (LV) strain on fetal ultrasound. IHC showed overt endocardial fibro-elastosis, which correlated with pathological fibrosis patterns in the myocardium and extremely disturbed cardiomyocyte organization. The LV in severe AS showed mildly reduced myocardial strain and less severe disorganization of the cardiomyocytes. In conclusion, the degree of reduction in myocardial deformation corresponded with high extent to the amount of pathological fibrosis patterns and cardiomyocyte disorganization. Myocardial deformation on fetal ultrasound seems to hold promise as a potential biomarker for left ventricular structural damage in AS.

Whilst knowledge regarding the pathophysiology of congenital heart disease (CHDs) has advanced greatly in recent years, the underlying developmental processes affecting the cardiac outflow tract (OFT) such as bicuspid aortic valve, tetralogy of Fallot and transposition of the great arteries remain poorly understood. Common among CHDs affecting the OFT, is a large variation in disease phenotypes. Even though the different cell lineages contributing to OFT development have been studied for many decades, it remains challenging to relate cell lineage dynamics to the morphologic variation observed in OFT pathologies. We postulate that the variation observed in cellular contribution in these congenital heart diseases might be related to underlying cell lineage dynamics of which little is known. We believe this gap in knowledge is mainly the result of technical limitations in experimental methods used for cell lineage analysis. The aim of this review is to provide an overview of historical fate mapping and cell tracing techniques used to study OFT development and introduce emerging technologies which provide new opportunities that will aid our understanding of the cellular dynamics underlying OFT pathology.

Background: Patients with a bicuspid aortic valve (BAV) are at risk of developing valve deterioration and aortic dilatation. We aimed to investigate whether blood biomarkers are associated with disease stage inpatients with BAV. Methods: Serum levels of high sensitivity C-reactive protein (hsCRP), high sensitivity troponin T (hsTnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and total transforming growth factor-beta 1 (TGF-beta 1) were measured in adult BAV patients with valve dysfunction or aortic pathology. Age-matched general population controls were included for TGF beta-1 measurements. Correlation analyses and multivariable linear regression were used to determine the association between (2log-transformed) biomarker levels and aortic valve regurgitation, aortic valve stenosis, aortic dilatation, or left ventricular function. Results: hsCRP and hsTnT were measured in the total group of 183 patients (median age 34 years, 25th-75th percentile 23-46), NT-proBNP in 162 patients, and TGF-beta 1 beta in 108 patients. Elevated levels of NT-proBNP were found in 20% of the BAV patients, elevated hsTnT in 6%, and elevated hsCRP in 7%. Higher hsTnT levels were independently associated with aortic regurgitation [odds ratio per doubling (OR2log) 1.34, 95% CI 1.01;1.76] and higher NT-proBNP levels with aortic valve maximal velocity (beta(2log) 0.17, 95%CI 0.07;028) and aortic regurgitation (OR2log 1.41, 95%CI 1.11;1.79). Both BAV patients with (9.9 +/- 2.7 ng/mL) and without aortic dilatation (10.4 +/- 2.9 ng/mL) showed lower TGF-beta 1 levels compared to general population controls (n = 85, 11.8 +/- 3.2 ng/mL). Conclusions: Higher NT-proBNP and hsTNT levels were associated with aortic valve disease in BAV patients. TGF-beta 1 levels were lower in BAV patients than in the general population, and not related to aortic dilatation. Longitudinal data are needed to further investigate the prognostic value of biomarkers in these patients. (C) 2020 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Background In a normal neonatal heart the ductus arteriosus forms the direct continuity of the pulmonary trunk to the descending aorta being the main channel for the prenatal blood flow. The pulmonary arteries originate separately from the pulmonary trunk. In congenital heart malformations with pulmonary stenosis to atresia there is often an abnormal lateral DA to left pulmonary artery connection combined with a localised narrowing (pulmonary ductal coarctation / PDC) or even interruption. We investigated embryonic remodelling and pathogenesis of this area Material and methods Normal development was studied in WntCre reporter mice (E10.0-12.5) for neural crest cells and Nkx2.5 immunostaining for second heart field cells. Data were compared to stage matched human embryos including histopathology of neonatal specimen, and a VEGF120/120 mutant mouse strain developing pulmonary atresia. Results Normal mouse and human embryos showed that, in the early embryo, the mid-pharyngeal endothelial plexus, partly covered by second heart field, connected side-ways to the 6 th pharyngeal arch artery (PAA). The ventral segment of this PAA effectively formed the proximal pulmonary artery. The origin of the cells encasing the endothelial tubes differed significantly. The dorsal 6 th PAA segment (future DA on the left side) was solely surrounded by neural crest cells. The ventral segment had a dual outer lining with neural crest cells laterally and second heart field cells medially, while the distal pulmonary artery was covered by neither of these cells. The asymmetric contribution of second heart field to the future pulmonary trunk on the left side of the aortic sac (so-called pulmonary push) was evident. During remodelling the ventral segment of the 6 th PAA became incorporated into the pulmonary trunk leading to a separate connection of the left and right pulmonary arteries to the latter. The VEGF120/120 embryos showed a severely stunted pulmonary push and later on a variety of vascular anomalies in the DA to pulmonary artery connections. Conclusion Side-way connection of the DA to the left pulmonary artery is a congenital anomaly. The primary problem is a stunted development of the second heart field-derived pulmonary push leading to pulmonary stenosis/atresia and a subsequent lack of proper incorporation of the ventral segment of the 6 th PAA into the aortic sac. Clinically, the aberrant smooth muscle tissue of the DA should be addressed to prohibit development of severe PDC or even interruption of the left pulmonary artery.

Despite the advent of new-generation drug-eluting stents, in-stent restenosis remains a significant problem in patients with coronary artery disease. In- stent restenosis is defined as the gradual re-narrowing of a stented coronary artery lesion due to arterial damage with subsequent local inflammation of the vessel wall and excessive growth of the vascular smooth muscle cells (vSMCs). Four-and-a-half LIM-domain protein 2 (FHL2) is a scaffold protein involved in regulating vSMC function and inflammation. Previously we have demonstrated that FHL2 prevents vSMC proliferation in a murine carotid artery ligation model. However, the effect of FHL2 on the inflammatory response of the vSMCs is not investigated. Therefore, we studied the inflammatory response in the vessel wall of FHL2-deficient (-KO) mice after carotid artery ligation. We found that circulating cytokines and local macrophage infiltration in the ligated carotid vessels were increased in FHL2-KO mice after carotid artery ligation. Moreover, FHL2-KO vSMCs showed increased secretion of cytokines such as SDF-1 alpha and RANTES, and enhanced activation of the NF kappa B pathway. Finally, we found that blocking the NF kappa B signalling pathway abrogated this pro-inflammatory state in FHL2-KO vSMCs. Taken together, our results demonstrate that FHL2 decreases the inflammatory response of vSMCs through inhibition of the NFkB-signalling pathway.

Background: Patients with a bicuspid aortic valve (BAV) have an increased risk for aortic dilation and dissection. In this study, we provide a histological stratification of the developing aorta in the tricuspid aortic valve (TAV) and the BAV populations as a reference for future studies on aortopathy and related syndromes. Methods: Non-dilated TAV and BAV ascending aortic wall samples were collected, including 60 TAV (embryonic&ndash, 70 years) and 32 BAV specimens (fetal&ndash, 72 years, categorized in eight age groups. Results: In TAV, intimal development starts in the neonatal phase. After birth, the thickness of the medial layer increases significantly by increase of elastic lamellae up to and including the &ldquo, young child&rdquo, phase stabilizing afterwards. The BAV shows already prenatal intimal thickening becoming significantly thinner after birth subsequently stabilizing. In BAV, increase in elastic lamellae is seen between the young child and the adolescent phases, stabilizing afterwards. Conclusions: Vascular development in TAV is described in three phases: maturation, stabilization, and degeneration. For BAV, the development can be described in two phases: maturation (already prenatally) and degeneration. After birth, the development of the aorta is characterized by degeneration, leading to weakening of the ascending aortic wall and increasing the risk of aortopathy.

The 19th century Russian surgeon Nikolay Ivanovich Pirogov believed passionately in the importance of anatomy for surgeons. His interest in anatomy began as a medical student in Moscow. After graduating in 1828 Pirogov entered the postgraduate German-Baltic University of Dorpat (now Tartu in the Republic of Estonia) where he studied anatomy and surgery. After completing his study, he remained to research the consequences of ligation of the aorta in a series of animal experiments, which formed the core of his doctoral thesis. He wanted to determine the feasibility of aortic ligation as a treatment for patients with an aneurysm of the aorta or iliac artery. He discovered that success was only likely when the aorta was ligated between the two mesenteric arteries and the ligature gradually tightened, an approach surgically difficult in humans. Pirogov then spent 2 years at the Charite Hospital in Berlin before returning to Russia. In 1841, he was appointed Professor of Applied Anatomy and Surgery at the Imperial Medico-Surgical Academy in Saint Petersburg. He instituted the teaching of microscopy and histology to the medical curriculum and in 1846 formed the Institute for Applied Anatomy within the academy, where in addition to teaching medical students future teachers of anatomy in Russia were trained. Pirogov published extensively on anatomy, including several anatomical atlases, the most notable his three-dimensional atlas of topographical anatomy published in four volumes between 1852 and 1859. Today Pirogov's contributions to anatomy are remembered in a number of anatomical structures named after him. Clin. Anat., 33:714-730, 2020. (c) 2019 Wiley Periodicals, Inc.

Background: A bicuspid aortic valve (BAV) is the most common congenital cardiac malformation and is associated with ascending aortic dilation in 60%-80% of patients. In this study, we aimed to address the role of hemodynamic influences on the development of aortopathy in BAV patients.Patient and methods: BAV (n=36) and tricuspid aortic valve (TAV) patients (n=17) undergoing aortic valve replacement underwent preoperative flow magnetic resonance imaging (MRI) assessment to detect the area of maximal flow-induced stress in the proximal aorta. Based on these MRI data, paired ascending aortic wall samples [i.e., area of maximal jet impact (jet sample) and the opposite aortic wall (nonjet sample)] were collected during surgery. To study and describe the effects of jet stream on the complete vascular wall, a pathology score was developed based on the recently published aortic consensus paper statement on surgical pathology of the aorta using routine histologic stainings (resorcin fuchsin, hematoxylin-eosin, and Movat) and immunohistochemistry (alpha smooth muscle actin, smooth muscle 22 alpha, platelet endothelial cell adhesion molecule).Results: Comparing the jet and nonjet samples in both BAV and TAV, regions of maximal jet impact did not show any difference in the pathology score in the adventitia and the middle and outer media. In the jet samples, the inner media however showed loss of actin expression in both BAV (P

The RHOA-ROCK signaling pathway is involved in numerous developmental processes, including cell proliferation, differentiation and migration. RHOA is expressed in the atrioventricular node (AVN) and altered expression of RHOA results in atrioventricular (AV) conduction disorders in mice. The current study aims to detect functional AVN disorders after disturbing RHOA-ROCK signaling in chicken embryos. RHOA-ROCK signaling was inhibited chemically by using the Rho-kinase inhibitor compound Y-27632 in avian embryos (20 experimental and 29 control embryos). Morphological examination of control embryos show a myocardial sinus venosus to atrioventricular canal continuity, contributing to the transitional zone of the AVN. ROCK inhibited embryos revealed lateralization and diminished myocardial sinus venosus to atrioventricular canal continuity and at the severe end of the phenotype hypoplasia of the AVN region. Ex ovo micro-electrode recordings showed an AV conduction delay in all treated embryos as well as cases with first, second (Wenkebach and Mobitz type) and third-degree AV block which could be explained by the spectrum of severity of the morphological phenotype. Laser capture microdissection and subsequent qPCR of tissue collected from this region revealed disturbed expression of HCN1, ISL1, and SHOX2. We conclude that RHOA-ROCK signaling is essential for normal morphological development of the myocardial continuity between the sinus venosus and AVN, contributing to the transitional zone, and possibly the compact AVN region. Disturbing the RHOA-ROCK signaling pathway results in AV conduction disturbances including AV block. The RHOA-ROCK inhibition model can be used to further study the pathophysiology and therapeutic strategies for AV block. Anat Rec, 302:83-92, 2019. (c) 2018 Wiley Periodicals, Inc.

ObjectiveIn patients with bicuspid aortic valve (BAV), coronary anatomy is variable. High take-off coronary arteries have been described, but data are scarce, especially when associated with complex congenital heart disease (CHD). The purpose of this study was to describe coronary patterns in these patients.MethodsIn 84 postmortem heart specimens with BAV and associated CHD, position and height of the coronary ostia were studied and related to BAV morphology.ResultsHigh take-off right (RCA) and left coronary arteries (LCA) were observed in 23% and 37% of hearts, respectively, most frequently in hearts with hypoplastic left ventricle (HLV) and outflow tract anomalies. In HLV, high take-off was observed in 18/40 (45%) more frequently of LCA (n=14) than RCA (n=6). In hearts with aortic hypoplasia, 8/13 (62%) had high take-off LCA and 6/13 (46%) high take-off RCA. High take-off was seen 19 times in 22 specimens with perimembranous ventricular septal defect (RCA 8, LCA 11). High take-off was associated with type 1A BAV (raphe between right and left coronary leaflets), more outspoken for the RCA. Separate ostia of left anterior descending coronary artery and left circumflex coronary artery were seen in four hearts (5%), not related to specific BAV morphology.ConclusionHigh take-off coronary arteries, especially the LCA, occur more frequently in BAV with associated CHD than reported in normal hearts and isolated BAV. Outflow tract defects and HLV are associated with type 1A BAV and high take-off coronary arteries. Although it is unclear whether these findings in infants with detrimental outcome can be related to surviving adults, clinical awareness of variations in coronary anatomy is warranted.

Background The clinical course of bicuspid aortic valves (BAVs) is variable. Data on predictors of aortopathy and valvular dysfunction mainly focus on valve morphology. Aim To determine whether the presence and extent of the raphe (fusion site of valve leaflets) is associated with the degree of aortopathy and valvular dysfunction in patients with isolated BAV and associated aortic coarctation (CoA). Methods Valve morphology and aortic dimensions of 255 BAV patients were evaluated retrospectively by echocardiography. Results BAVs with a complete raphe had a significantly higher prevalence of valve dysfunction (especially aortic regurgitation) than BAVs with incomplete raphes (82.9 vs. 66.7 %, p = 0.01). Type 1A BAVs (fusion of right and left coronary leaflets) and complete raphe had larger aortic sinus diameters compared with the rest of the population (37.74 vs. 36.01, p = 0.031). Patients with CoA and type 1A BAV had significantly less valve regurgitation (13.6 vs. 55.8 %, p p p Conclusions Type 1A BAV with complete raphe is associated with more aortic regurgitation and root dilatation. The majority of CoA patients have incomplete raphes, associated with smaller aortic root diameters and less valve regurgitation.

Objective Variable coronary anatomy has been described in patients with bicuspid aortic valves (BAVs). This was never specified to BAV morphology, and prognostic relevance of coronary vessel dominance in this patient group is unclear. The purpose of this study was to evaluate valve morphology in relation to coronary artery anatomy and outcome in patients with isolated BAV and with associated aortic coarctation (CoA). Methods Coronary anatomy was evaluated in 186 patients with BAV (141 men (79%), 51±14 years) by CT and invasive coronary angiography. Correlation of coronary anatomy was made with BAV morphology and coronary events. Results Strictly bicuspid valves (without raphe) with left-right cusp fusion (type 1B) had more left dominant coronary systems compared with BAVs with left-right cusp fusion with a raphe (type 1A) (48% vs. 26%, p=0.047) and showed more separate ostia (28% vs. 9%, p=0.016). Type 1B BAVs had more coronary artery disease than patients with type 1A BAV (36% vs. 19%, p=0.047). More left dominance was seen in BAV patients with CoA than in patients without (65% vs. 24%, p Conclusions The incidence of a left dominant coronary artery system and separate ostia was significantly related to BAVs with left-right fusion without a raphe (type 1B). These patients more often had significant coronary artery disease. In patients with BAV and CoA, left dominancy is more common.

Supplemental digital content is available in the text., Objective In ovarian cancer, detection of sentinel nodes is an upcoming procedure. Perioperative determination of the patient’s sentinel node(s) might prevent a radical lymphadenectomy and associated morbidity. It is essential to understand the lymphatic drainage pathways of the ovaries, which are surprisingly up till now poorly investigated, to predict the anatomical regions where sentinel nodes can be found. We aimed to describe the lymphatic drainage pathways of the human ovaries including their compartmental fascia borders. Methods A series of 3 human female fetuses and tissues samples from 1 human cadaveric specimen were studied. Immunohistochemical analysis was performed on paraffin-embedded transverse sections (8 or 10 μm) using antibodies against Lyve-1, S100, and α-smooth muscle actin to identify the lymphatic endothelium, Schwann, and smooth muscle cells, respectively. Three-dimensional reconstructions were created. Results Two major and 1 minor lymphatic drainage pathways from the ovaries were detected. One pathway drained via the proper ligament of the ovaries (ovarian ligament) toward the lymph nodes in the obturator fossa and the internal iliac artery. Another pathway drained the ovaries via the suspensory ligament (infundibulopelvic ligament) toward the para-aortic and paracaval lymph nodes. A third minor pathway drained the ovaries via the round ligament to the inguinal lymph nodes. Lymph vessels draining the fallopian tube all followed the lymphatic drainage pathways of the ovaries. Conclusions The lymphatic drainage pathways of the ovaries invariably run via the suspensory ligament (infundibulopelvic ligament) and the proper ligament of the ovaries (ovarian ligament), as well as through the round ligament of the uterus. Because ovarian cancer might spread lymphogenously via these routes, the sentinel node can be detected in the para-aortic and paracaval regions, obturator fossa and surrounding internal iliac arteries, and inguinal regions. These findings support the strategy of injecting tracers in both ovarian ligaments to identify sentinel nodes.

Background Excellent anatomical knowledge of the rectum and surrounding structures is essential for total mesorectal excision (TME). Denonviliers' fascia (DVF) has been frequently studied, though the optimal anterior plane in TME is still disputed. The relationship of the lateral edges of DVF to the autonomic nerves and mesorectal fascia is unclear. We studied whole mout microscopic sections of en-bloc cadaveric pelvic exenteration and describe implications for TME. Methods Four donated human adult cadaveric specimens (two males, two females) were obtained from the Leeds GIFT Research Tissue Programme. Paraffin-embedded mega blocks were produced and serially sectioned at 50 and 250 μm intervals. Sections were stained with haematoxylin & eosin, Masson's trichrome and Millers' elastin. Additionally, a series of eleven human fetal specimens (embryonic age of 9–20 weeks) were studied. Results DVF consisted of multiple fascial condensations of collagen and smooth muscle fibres and was indistinguishable from the anterior mesorectal fascia and the prostatic fascia or posterior vaginal wall. The lateral edges of DVF appeared fan-shaped and the most posterior part was continuous with the mesorectal fascia. Fasciae were not identified in fetal specimens. Conclusion DVF is adherent to and continuous with the mesorectal fascia. Optimal surgical dissection during TME should be carried out anterior to DVF to ensure radical removal, particularly for anterior tumours. Autonomic nerves are at risk, but can be preserved by closely following the mesorectal fascia along the anterolateral mesorectum. The lack of evident fasciae in fetal specimens suggested that these might be formed in later developmental stages.

Objectives Variations in coronary anatomy are common and may relate to the position of the coronary ostium relative to the aortic sinus, the angle of coronary take-off, or the course of the coronary arterial branches. Several classification systems have been proposed. However, they all lack a simple rationale that is applicable irrespective of the relative position of the great arteries, as well as in bicuspid aortic valves. We present a modification of a relatively simple system introduced in the early 1980s, designated the "Leiden Convention." Methods The first step of the Leiden Convention is that the clinician takes position in the nonfacing sinus of the aorta looking toward the pulmonary orifice. The right-hand facing sinus is sinus 1, and the left-hand facing sinus is sinus 2. The coronary branches arising from sinus 1 are annotated proceeding in a counterclockwise fashion toward sinus 2. "Usual" (normal) coronary anatomy would be 1R-2LCx. Given their clinical relevance, single sinus coronary arteries are discussed separately. Results This system was originally designed and highly applicable in hearts with an altered great artery relationship, such as in the variable and complicated patterns seen in transposition of the great arteries and double outlet right ventricle. The modified system also can be used in cases with normally related great arteries, cases with single sinus coronary arteries, and cases with bicuspid aortic valves. Conclusions The modified Leiden Convention is not a strict classification but a simple coronary coding system that is broadly applicable.

Massive open online courses (MOOCs) are a novel mode of online learning. They are typically based on higher education courses and can attract a high number of learners, often in the thousands. They are distinct from on-campus education and deliver the learning objectives through a series of short videos, recommended readings and discussion fora, alongside automated assessments. Within medical education the role of MOOCs remains unclear, with recent proposals including continuing professional development, interprofessional education or integration into campus-based blended learning curricula. In this twelve tips article, we aim to provide a framework for readers to use when developing, delivering and evaluating a MOOC within medical education based on the literature and our own experience. Practical advice is provided on how to design the appropriate curriculum, engage with learners on the platform, select suitable assessments, and comprehensively evaluate the impact of your course.

Aim Lipoprotein related receptor protein type 2 (LRP2) is highly expressed on both yolk sac and placenta. Mutations in the corresponding gene are associated with severe birth defects in humans, known as Donnai-Barrow syndrome. We here characterized the contribution of LRP2 and maternal plasma cholesterol availability to maternal-fetal cholesterol transport and fetal cholesterol levels in utero in mice. Methods Lrp2+/- mice were mated heterozygously to yield fetuses of all 3 genotypes. Half of the dams received a 0.5% probucol enriched diet during gestation to decrease maternal HDL cholesterol. At E13.5 the dams received an injection of D7 labeled cholesterol and were provided with 1-13C acetate-supplemented drinking water. At E16.5, fetal tissues were collected and maternal cholesterol transport and fetal synthesis quantified by isotope enrichments in fetal tissues by GC-MS. Results The Lrp2 genotype did not influence maternal-fetal cholesterol transport and fetal cholesterol. However, lowering of maternal plasma cholesterol levels by probucol significantly reduced maternal-fetal cholesterol transport. In the fetal liver, this was associated with increased cholesterol synthesis rates. No indications were found for an interaction between the Lrp2 genotype and maternal probucol treatment. Conclusions Maternal-fetal cholesterol transport and endogenous fetal cholesterol synthesis depend on maternal cholesterol concentrations but do not involve LRP2 in the second half of murine pregnancy. Our results suggest that the mouse fetus can compensate for decreased maternal cholesterol levels. It remains a relevant question how the delicate system of cholesterol transport and synthesis is regulated in the human fetus and placenta. This article is protected by copyright. All rights reserved.

Aims RHOA-ROCK signalling regulates cell migration, proliferation, differentiation, and transcription. RHOA is expressed in the developing cardiac conduction system in chicken and mice. In early development, the entire sinus venosus myocardium, including both the transient left-sided and the definitive sinoatrial node (SAN), has pacemaker potential. Later, pacemaker potential is restricted to the right-sided SAN. Disruption of RHOA expression in adult mice causes arrhythmias including bradycardia and atrial fibrillation, the mechanism of which is unknown but presumed to affect the SAN. The aim of this study is to assess the role of RHOA-ROCK signalling in SAN development in the chicken heart. Methods and results ROCK signalling was inhibited chemically in embryonic chicken hearts using Y-27632. This prolonged the immature state of the sinus venosus myocardium, evidenced by up-regulation of the transcription factor ISL1, wide distribution of pacemaker potential, and significantly reduced heart rate. Furthermore ROCK inhibition caused aberrant expression of typical SAN genes: ROCK1, ROCK2, SHOX2, TBX3, TBX5, ISL1, HCN4, CX40, CAV3.1, and NKX2.5 and left-right asymmetry genes: PITX2C and NODAL. Anatomical abnormalities in pulmonary vein development were also observed. Patch clamp electrophysiology confirmed the immature phenotype of the SAN cells and a residual left-sided sinus venosus myocardium pacemaker-like potential. Conclusions RHOA-ROCK signalling is involved in establishing the right-sided SAN as the definitive pacemaker of the heart and restricts typical pacemaker gene expression to the right side of the sinus venosus myocardium.

Due to the intricate relationship between the pelvic organs and vital structures, such as vessels and nerves, pelvic anatomy is often considered to be complex to comprehend. In oncological pelvic surgery, a trade-off has to be made between complete tumor resection and preserving function by preventing damage to the nerves. Damage to the autonomic nerves causes undesirable post-operative side-effects such as fecal and urinal incontinence, as well as sexual dysfunction in up to 80 percent of the cases. Since these autonomic nerves are not visible in pre-operative MRI scans or during surgery, avoiding nerve damage during such a surgical procedure becomes challenging. In this work, we present visualization methods to represent context, target, and risk structures for surgical planning. We employ distance-based and occlusion management techniques in an atlas-based surgical planning tool for oncological pelvic surgery. Patient-specific pre-operative MRI scans are registered to an atlas model that includes nerve information. Through several interactive linked views, the spatial relationships and distances between the organs, tumor and risk zones are visualized to improve understanding, while avoiding occlusion. In this way, the surgeon can examine surgically relevant structures and plan the procedure before going into the operating theater, thus raising awareness of the autonomic nerve zone regions and potentially reducing post-operative complications. Furthermore, we present the results of a domain expert evaluation with surgical oncologists that demonstrates the advantages of our approach.

The autonomic nervous system (cANS) is essential for proper heart function, and complications such as heart failure, arrhythmias and even sudden cardiac death are associated with an altered cANS function. A changed innervation state may underlie (part of) the atrial and ventricular arrhythmias observed after myocardial infarction. In other cardiac diseases, such as congenital heart disease, autonomic dysfunction may be related to disease outcome. This is also the case after heart transplantation, when the heart is denervated. Interest in the origin of the autonomic nerve system has renewed since the role of autonomic function in disease progression was recognized, and some plasticity in autonomic regeneration is evident. As with many pathological processes, autonomic dysfunction based on pathological innervation may be a partial recapitulation of the early development of innervation. As such, insight into the development of cardiac innervation and an understanding of the cellular background contributing to cardiac innervation during different phases of development is required. This review describes the development of the cANS and focuses on the cellular contributions, either directly by delivering cells or indirectly by secretion of necessary factors or cell-derivatives.

The avian embryo has long been a popular model system in developmental biology. The easy accessibility of the embryo makes it particularly suitable for in ovo microsurgery and manipulation. Re-incubation of the embryo allows long-term follow-up of these procedures. The current review focuses on the variety of techniques available to study development of the cardiac conduction system in avian embryos. Based on the large amount of relevant data arising from experiments in avian embryos, we conclude that the avian embryo has and will continue to be a powerful model system to study development in general and the developing cardiac conduction system in particular.

ObjectiveRadical hysterectomy with pelvic lymphadenectomy (RHL) is the preferred treatment for early-stage cervical cancer. Although oncological outcome is good with regard to recurrence and survival rates, it is well known that RHL might result in postoperative bladder impairments due to autonomic nerve disruption. The pelvic autonomic network has been extensively studied, but the anatomy of nerve fibers branching off the inferior hypogastric plexus to innervate the bladder is less known. Besides, the pathogenesis of bladder dysfunction after RHL is multifactorial but remains unclear. We studied the 3-dimensional anatomy and neuroanatomical composition of the vesical plexus and describe implications for RHL.Materials and MethodsSix female adult cadaveric pelvises were macroscopically dissected. Additionally, a series of 10 female fetal pelvises (embryonic age, 10–22 weeks) was studied. Paraffin-embedded blocks were transversely sliced in 8-μm sections. (Immuno) histological analysis was performed with hematoxylin and eosin, azan, and antibodies against S-100 (Schwann cells), tyrosine hydroxylase (postganglionic sympathetic fibers), and vasoactive intestinal peptide (postganglionic parasympathetic fibers). The results were 3-dimensionally visualized.ResultsThe vesical plexus formed a group of nerve fibers branching off the ventral part of the inferior hypogastric plexus to innervate the bladder. In all adult and fetal specimens, the vesical plexus was closely related to the distal ureter and located in both the superficial and deep layers of the vesicouterine ligament. Efferent nerve fibers belonging to the vesical plexus predominantly expressed tyrosine hydroxylase and little vasoactive intestinal peptide.ConclusionsThe vesical plexus is located in both layers of the vesicouterine ligament and has a very close relationship with the distal ureter. Complete mobilization of the ureter in RHL might cause bladder dysfunction due to sympathetic and parasympathetic denervation. Hence, the distal ureter should be regarded as a risk zone in which the vesical plexus can be damaged.

Patients with bicuspid aortic valve (BAV) and patients with Marfan syndrome (MFS) are more prone to develop aortic dilation and dissection compared to persons with a tricuspid aortic valve (TAV). To elucidate potential common and distinct pathways of clinical relevance, we compared the histopathological substrates of aortopathy. Ascending aortic wall biopsies were divided in five groups: BAV (n = 36) and TAV (n = 23) without and with dilation and non-dilated MFS (n = 8). General histologic features, apoptosis, the expression of markers for vascular smooth muscle cell (VSMC) maturation, markers predictive for ascending aortic dilation in BAV, and expression of fibrillin-1 were investigated. Both MFS and BAV showed an altered distribution and decreased fibrillin-1 expression in the aorta and a significantly lower level of differentiated VSMC markers. Interestingly, markers predictive for aortic dilation in BAV were not expressed in the MFS aorta. The aorta in MFS was similar to the aorta in dilated TAV with regard to the presence of medial degeneration and apoptosis, while other markers for degeneration and aging like inflammation and progerin expression were low in MFS, comparable to BAV. Both MFS and BAV aortas have immature VSMCs, while MFS and TAV patients have a similar increased rate of medial degeneration. However, the mechanism leading to apoptosis is expected to be different, being fibrillin-1 mutation induced increased angiotensin-receptor-pathway signaling in MFS and cardiovascular aging and increased progerin in TAV. Our findings could explain why angiotensin inhibition is successful in MFS and less effective in TAV and BAV patients.

Introduction and hypothesis The objective of this study was the assessment of the efficiency of the MiniArc for curing stress urinary incontinence. Methods Seventy-seven patients, operated on from March 2008 to November 2009, were evaluated in this study. One-year post-operative data are presented. All patients suffered from predominant stress urinary incontinence. After 1 year, response was 74%. Evaluation was performed using a questionnaire consisting of the EuroQol-5 Dimensions, the Patient Global Impression of Improvement, the Incontinence Impact Questionnaire, the Urinary Distress Inventory, the Prolapse/Urinary Incontinence Sexual Questionnaire, short form, and the Defecation Distress Inventory. Results One year after surgery, 68% of the patients stated an improvement in their incontinence status, while only 44% stated to be completely dry. Conclusion The 1-year follow-up suggests that the MiniArc is less effective in the treatment of stress urinary incontinence than the TVT.

Background: Normally, the inside of the left atrial (LA) body and pulmonary veins (PVs) is lined by vessel wall tissue covered by myocardium. In total anomalous pulmonary venous connection (TAPVC), no connection of the PVs with the LA body exists. These veins have an increased incidence of PV stenosis. We describe the consequences of the absent connection for the histopathology of the wall of the LA body and the PVs, and hypothesize on a mechanism predisposing to PV stenosis.Methods and results: In 10 human neonates with TAPVC, the wall of the LA body and PVs were studied using histological and immunohistochemical techniques. As controls, 2 normal neonatal and adult hearts and 5 neonatal hearts with partial anomalous venous connection (PAPVC) or situs inversus were studied. In hearts with TAPVC no vessel wall tissue was found in the LA body and its myocardial layer was hypoplastic. No myocardial sleeve was found around the abnormally draining PVs. In hearts with PAPVC, only the non-LA draining PV lacked myocardial covering, whereas in situs inversus PVs connecting to the right-sided LA, were normally myocardialized.Conclusion: An open connection of the PVs with the morphological LA is necessary for the presence of vessel wall tissue in the LA and myocardialization of the PVs. Absence of myocardium covering the PVs is hypothesized to enhance susceptibility to PV stenosis and prevent onset of PV originating arrhythmias. The embryonic posterior heart field may be responsible for the abnormal myocardialization and smooth muscle cell formation in TAPVC. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Objectives The contributions of the pudendal and levator ani nerves to the innervation of the levator ani muscle (LAM) are disputed. Because of the relatively large size of the nerves in early life, we investigated this issue in human fetuses. Methods (Immuno)histochemically stained serial sections of nine human fetuses (9–22 wk of gestation) were investigated. Both the left and right sides of the fetal pelves were studied individually and 3D reconstructions were prepared. Results The levator ani nerve innervated the LAM in every pelvis, whereas a contribution of the pudendal nerve to the innervation of the LAM could be demonstrated in only 10 pelvic halves (56%). In 10 halves, we observed a communicating nerve branch between the pudendal and levator ani nerves that pierced the pelvic floor between the LAM and the coccygeus muscle. No sex differences were observed, but the innervation pattern did differ between the left and right side of a pelvis. Conclusions The LAM often has a dual somatic innervation with the levator ani nerve as its constant and main neuronal supply.

Aim Excellent understanding of fasciae and nerves surrounding the rectum is necessary for total mesorectal excision (TME). However, fasciae anterolateral to the rectum and surrounding the low rectum are still poorly understood. We studied the perirectal fascia enfolding the extraperitoneally located part of the rectum in en-bloc cadaveric specimens and the University Medical Center Utrecht (UMCU) pelvic dataset, and describe implications for TME. Methods Four donated human adult cadaveric specimens (two males, two females) were obtained through the Leeds GIFT Research Tissue Programme. Paraffin-embedded blocks were produced and serially sectioned at 50 and 250 μm intervals. Whole mount sections were stained with haematoxylin & eosin, Masson's trichrome and Millers' elastin. Additionally, the UMCU pelvic dataset including digitalised cryosections of a female pelvis in three axes was studied. Results The mid and lower rectum were surrounded by a multi-layered perirectal fascia, of which the mesorectal fascia (MRF) and parietal fascia bordered the ‘holy plane'. There was no extra constant fascia forming a potential surgical plane. Nerves ran laterally to the MRF. More caudally, the mesorectal fat strongly reduced and the MRF approached the rectal muscularis propria. The MRF had a variable appearance in terms of thickness and completeness, most prominently at the anterolateral lower rectum. Conclusion Dissection onto the MRF allows nerve preservation in TME. Rectal surgeons are challenged in doing so as the MRF varies in thickness and shows gaps, most prominently at the anterolateral lower rectum. At this site, the risk of entering the mesorectum is great and may result in an incomplete specimen.

Objective— Arterial calcification is considered a major cause of death and disabilities worldwide because the associated vascular remodeling leads to myocardial infarction, stroke, aneurysm, and pulmonary embolism. This process occurs via poorly understood mechanisms involving a variety of cell types, intracellular mediators, and extracellular cues within the vascular wall. An inverse correlation between endothelial primary cilia and vascular calcified areas has been described although the signaling mechanisms involved remain unknown. We aim to investigate the signaling pathways regulated by the primary cilium that modulate the contribution of endothelial cells to vascular calcification. Approach and Results— We found that human and murine endothelial cells lacking primary cilia are prone to undergo mineralization in response to bone morphogenetic proteins stimulation in vitro. Using the Tg737 orpk/orpk cillium-defective mouse model, we show that nonciliated aortic endothelial cells acquire the ability to transdifferentiate into mineralizing osteogenic cells, in a bone morphogenetic protein–dependent manner. We identify β-CATENIN–induced SLUG as a key transcription factor controlling this process. Moreover, we show that the endothelial expression of SLUG is restricted to atheroprone areas in the aorta of LDLR −/− mice. Finally, we demonstrate that SLUG and phospho-homolog of the Drosophila protein, mothers against decapentaplegic (MAD) and the Caenorhabditis elegans protein SMA (from gene sma for small body size)-1/5/8 expression increases in endothelial cells constituting the vasa vasorum in the human aorta during the progression toward atherosclerosis. Conclusions— We demonstrated that the lack of primary cilia sensitizes the endothelium to undergo bone morphogenetic protein–dependent-osteogenic differentiation. These data emphasize the role of the endothelial cells on the vascular calcification and uncovers SLUG as a key target in atherosclerosis.

Sun et al. (1) report that the dorsal mesenchymal protrusion (DMP) acts as a temporary pacemaker during early development, prior to formation of the atrioventricular node (AVN). We would like to question whether the anatomical designation of the DMP used in this paper is correct. The DMP was originally described as a mesenchymal protrusion from the dorsal mesocardium toward the atrial cavity contributing to the base of the atrial septum along with the mesenchymal cap and AV cushions (see Fig. 1) (2). To differentiate between the DMP prior to muscularization (which occurs from approximately embryonic day (E)13 in mouse) and other structures in the AV junction (AVJ) during early development, stainings of myocardial markers are essential, which are lacking in the paper by Sun et al. (1). In our opinion, the Shox2+ region described by Sun et al. (1) as DMP at E11.5 and E12.5 corresponds to CTNI+/HCN4+/ISL1+ cells of the putative AVN region and not the DMP (CTNI−/HCN4−/ISL1+) (see Fig. 1 and Refs. 3 and 4). HCN4 expression to date has not been described in mesenchyme (3,–5). Co-expression of HCN4/TBX3 in cells in the AVJ, with nodal-like electrophysiological characteristics (1) corresponds to the (putative) AVN region instead of the DMP, which is in accordance with our own observations (4). Misnaming the DMP during early development leads to the erroneous conclusion that this structure shows pacemaking properties. FIGURE 1. Description of structures in the atrioventricular junction at E11.5. Panels A–E show transverse sections just below the entrance of the pulmonary veins. A, overview of CTNI/HCN4/ISL1 staining. Boxed area is shown in B–E. B, merge of different ... Although we do not support the conclusion that the DMP acts as a temporary pacemaker, the results described by Sun et al. (1) elegantly show an important role for the Shox2-BMP pathway during AVN development.

During embryonic development, the common pulmonary vein (PV) becomes incorporated into the left atrium, giving rise to separate PV ostia. We describe the consequences of this incorporation process for the histology of the left atrium and the possible clinical implications. The histology of the left atrial (LA) wall in relation to PV incorporation was studied immunohistochemically in 16 human embryos and fetuses, 1 neonate, and 5 adults. The PV wall, surrounded by extrapericardially differentiated myocardial cells, was incorporated into the LA body. After incorporation, the composition of PVs and the smooth-walled LA body wall was histologically identical. The LA appendage, however, consisted of endocardial and myocardial layers without a vessel wall component. In 2 adults, the myocardium in the LA posterior wall was absent. At the transition of the LA body and LA appendage, a smooth-walled myocardial zone lacking the venous wall was observed. This zone was histologically identical to the sinus venarum of the right atrium. In conclusion, the LA body arises by incorporation and growth of PVs, presenting with a histologically identical structure of vessel wall covered by extrapericardially differentiated myocardium of PVs. Discontinuity of myocardium may be the substrate for arrhythmias, and absence of myocardium in some patients makes this area potentially vulnerable to damage inflicted by ablation strategies. A border zone between the LA body and LA appendage is hypothesized to be the left part of the embryonic sinus venosus. (C) 2006 Elsevier Inc. All rights reserved.

Autonomic nerve damage during surgery is thought to play a crucial role in the aetiology of bladder dysfunction, sexual dysfunction and colorectal motility disorders which are seen in patients after radical hysterectomy. In order to prevent these complications, Japanese gynaecologists introduced a surgical technique with preservation of the pelvic autonomic nerves in the 1960s. In the 1980s the first English paper was published. Since then several surgical approaches have been described, i.e. liposuction, electrical stimulation to locate nerves intra-operatively and laparoscopically assisted techniques. Recently, more attention is being paid to the importance of sparing the sympathetic hypogastric nerve. All authors report results on small cohorts of patients. The incidence of urinary dysfunction seems very low after nerve sparing. Sparing the autonomic nerves during radical hysterectomy seems feasible and safe in both Japanese and Western patients. Literature review does not provide strong clues for a compromised radicality and cure due to nerve sparing. Future larger clinical trials will have to decide whether the technique of nerve sparing radical hysterectomy could be implemented as a standard treatment for cervical cancer patients.