The heart develops from mesodermal cardiogenic fields on either side of the embryo that fuse to form a primitive heart tube. This tube undergoes looping to the right, forming the chambers. Partitioning forms the atrial and ventricular septa, separating the chambers. In fetal circulation, blood is shunted away from the lungs through openings like the foramen ovale and ductus arteriosus. At birth, these close as the lungs become functional and circulation assumes the postnatal pattern. Defects can occur if septation or closure of passages is incomplete, leading to congenital heart diseases.
The conotruncus comprises collectively two myocardial subsegments, the conus and the truncus.
Conus is the myocardial segment between ventricle and semi lunar valves which gives rise to sub arterial coni.
Truncus is the fibrous segment between semi lunar valves and aortic sac which gives rise to great arteries.
Development of heart in embryology.
● Formation and position of the heart tube.
● Formation and position of the heart loop
● Mechanism of cardiac looping
● Formation of the embryonic ventricle
● Development of the sinus venosus
● Formation of the cardiac septa
● Atrial septation
● The atrio-ventricular canal
● The muscular interventricular septum
● The septum in truncus arteriosus and the cordis conus
The conotruncus comprises collectively two myocardial subsegments, the conus and the truncus.
Conus is the myocardial segment between ventricle and semi lunar valves which gives rise to sub arterial coni.
Truncus is the fibrous segment between semi lunar valves and aortic sac which gives rise to great arteries.
Development of heart in embryology.
● Formation and position of the heart tube.
● Formation and position of the heart loop
● Mechanism of cardiac looping
● Formation of the embryonic ventricle
● Development of the sinus venosus
● Formation of the cardiac septa
● Atrial septation
● The atrio-ventricular canal
● The muscular interventricular septum
● The septum in truncus arteriosus and the cordis conus
Embryology Course VI - Cardiovascular SystemRawa Muhsin
This session discusses the development of the cardiovascular system and includes:
1. Development of the heart
2. Development of the arterial system
3. Development of the venous system
4. Development of lymphatics, overview of fetal circulation, and changes in fetal circulation at birth
Wellens syndrome. Wellens syndrome (also referred to as LAD coronary T-wave syndrome) refers to an ECG pattern specific for critical stenosis of the proximal left anterior descending artery. The anomalies described occur in patients with recent anginal chest pain, and do not have chest pain when the ECG is recorded.
Congenital defects can put a strain on the heart, causing it to work harder. To stop your heart from getting weaker with this extra work, your doctor may try to treat you with medications. They are aimed at easing the burden on the heart muscle. You need to control your blood pressure if you have any type of heart problem.
Changing your lifestyle can help control and manage high blood pressure. Your health care provider may recommend that you make lifestyle changes including:
Eating a heart-healthy diet with less salt
Getting regular physical activity
Maintaining a healthy weight or losing weight
Limiting alcohol
Not smoking
Getting 7 to 9 hours of sleep daily
CRISPR technologies have progressed by leaps and bounds over the past decade, not only having a transformative effect on
biomedical research but also yielding new therapies that are poised to enter the clinic. In this review, I give an overview of (i)
the various CRISPR DNA-editing technologies, including standard nuclease gene editing, base editing, prime editing, and epigenome editing, (ii) their impact on cardiovascular basic science research, including animal models, human pluripotent stem
cell models, and functional screens, and (iii) emerging therapeutic applications for patients with cardiovascular diseases, focusing on the examples of Hypercholesterolemia, transthyretin amyloidosis, and Duchenne muscular dystrophy.
A post-splenectomy patient suffers from frequent infections due to capsulated bacteria like Streptococcus
pneumoniae, Hemophilus influenzae, and Neisseria meningitidis despite vaccination because of a lack of
memory B lymphocytes. Pacemaker implantation after splenectomy is less common. Our patient underwent
splenectomy for splenic rupture after a road traffic accident. He developed a complete heart block after
seven years, during which a dual-chamber pacemaker was implanted. However, he was operated on seven
times to treat the complication related to that pacemaker over a period of one year because of various
reasons, which have been shared in this case report. The clinical translation of this interesting observation
is that, though the pacemaker implantation procedure is a well-established procedure, the procedural
outcome is influenced by patient factors like the absence of a spleen, procedural factors like septic measures,
and device factors like the reuse of an already-used pacemaker or leads.
Transcatheter closure of patent ductus arteriosus (PDA) is feasible in low-birth-weight infants. A female baby was born prematurely with a birth weight of 924 g. She had a PDA measuring 3.7 mm. She was dependent on positive pressure ventilation for congestive heart failure in addition to the heart failure medications. She could not be discharged from the hospital even after 79 days of birth, and even though her weight reached 1.9 kg in the neonatal intensive care unit. We attempted to plug the PDA using an Amplatzer Piccolo Occluder, but the device failed to anchor. Then, the PDA was plugged using a 4-6 Amplatzer Duct Occluder using a 6-Fr sheath which was challenging.
Accidental misplacement of the limb lead electrodes is a common cause of ECG abnormality and may simulate pathology such as ectopic atrial rhythm, chamber enlargement or myocardial ischaemia and infarction
A Case of Device Closure of an Eccentric Atrial Septal Defect Using a Large D...Ramachandra Barik
Device closure of an eccentric atrial septal defect can be challenging and needs technical modifications to avoid unnecessary complications. Here, we present a case of a 45-year-old woman who underwent device closure of an eccentric defect with a large device. The patient developed pericardial effusion and left-sided pleural effusion due to injury to the junction of right atrium and superior vena cava because of the malalignment of the delivery sheath and left atrial disc before the device was pulled across the eccentric defect despite releasing the left atrial disc in the left atrium in place of the left pulmonary vein. These two serious complications were managed conservatively with close monitoring of the case during and after the procedure.
Trio of Rheumatic Mitral Stenosis, Right Posterior Septal Accessory Pathway a...Ramachandra Barik
A 57-year-old male presented with recurrent palpitations. He was diagnosed with rheumatic mitral stenosis, right posterior septal accessory pathway and atrial flutter. An electrophysiological study after percutaneous balloon mitral valvotomy showed that the palpitations were due to atrial flutter with right bundle branch aberrancy. The right posterior septal pathway was a bystander because it had a higher refractory period than the atrioventricular node.
Percutaneous balloon dilatation, first described by
Andreas Gruentzig in 1979, was initially performed
without the use of guidewires.1 The prototype
balloon catheter was developed as a double lumen
catheter (one lumen for pressure monitoring or
distal perfusion, the other lumen for balloon inflation/deflation) with a short fixed and atraumatic
guidewire at the tip. Indeed, initially the technique
involved advancing a rather rigid balloon catheter
freely without much torque control into a coronary
artery. Bends, tortuosities, angulations, bifurcations,
and eccentric lesions could hardly, if at all, be negotiated, resulting in a rather frustrating low procedural success rate whenever the initial limited
indications (proximal, short, concentric, noncalcified) were negated.2 Luck was almost as
important as expertise, not only for the operator,
but also for the patient. It is to the merit of
Simpson who, in 1982, introduced the novelty of
advancing the balloon catheter over a removable
guidewire, which had first been advanced in the
target vessel.3 This major technical improvement
resulted overnight in a notable increase in the procedural success rate. Guidewires have since evolved
into very sophisticated devices.
Optical coherence tomography-guided algorithm for percutaneous coronary intervention. Vessel diameter should be assessed using the external elastic lamina (EEL)-EEL diameter at the reference segments, and rounded down to select interventional devices (balloons, stents). If the EEL cannot be identified, luminal measures are used and rounded up to 0.5 mm larger for selection of the devices. Optical coherence tomography (OCT)-guided optimisation strategies post stent implantation per EEL-based diameter measurement and per lumen-based diameter measurement are shown. For instance, if the distal EEL-EEL diameter measures 3.2 mm×3.1 mm (i.e., the mean EEL-based diameter is 3.15 mm), this number is rounded down to the next available stent size and post-dilation balloon to be used at the distal segment. Thus, a 3.0 mm stent and non-compliant balloon diameter is selected. If the proximal EEL cannot be visualised, the mean lumen diameter should be used for device sizing. For instance, if the mean proximal lumen diameter measures 3.4 mm, this number is rounded up to the next available balloon diameter (within up to 0.5 mm larger) for post-dilation. MLA: minimal lumen area; MSA: minimal stent area;NC: non-compliant
Brugada syndrome (BrS) is an inherited cardiac disorder,
characterised by a typical ECG pattern and an increased
risk of arrhythmias and sudden cardiac death (SCD).
BrS is a challenging entity, in regard to diagnosis as
well as arrhythmia risk prediction and management.
Nowadays, asymptomatic patients represent the majority
of newly diagnosed patients with BrS, and its incidence
is expected to rise due to (genetic) family screening.
Progress in our understanding of the genetic and
molecular pathophysiology is limited by the absence
of a true gold standard, with consensus on its clinical
definition changing over time. Nevertheless, novel
insights continue to arise from detailed and in-depth
studies, including the complex genetic and molecular
basis. This includes the increasingly recognised
relevance of an underlying structural substrate. Risk
stratification in patients with BrS remains challenging,
particularly in those who are asymptomatic, but recent
studies have demonstrated the potential usefulness
of risk scores to identify patients at high risk of
arrhythmia and SCD. Development and validation of
a model that incorporates clinical and genetic factors,
comorbidities, age and gender, and environmental
aspects may facilitate improved prediction of disease
expressivity and arrhythmia/SCD risk, and potentially
guide patient management and therapy. This review
provides an update of the diagnosis, pathophysiology
and management of BrS, and discusses its future
perspectives.
The Human Developmental Cell Atlas (HDCA) initiative, which is part of the Human Cell Atlas, aims to create a comprehensive reference map of cells during development. This will be critical to understanding normal organogenesis, the effect of mutations, environmental factors and infectious agents on human development, congenital and childhood disorders, and the cellular basis of ageing, cancer and regenerative medicine. Here we outline the HDCA initiative and the challenges of mapping and modelling human development using state-of-the-art technologies to create a reference atlas across gestation. Similar to the Human Genome Project, the HDCA will integrate the output from a growing community of scientists who are mapping human development into a unified atlas. We describe the early milestones that have been achieved and the use of human stem-cell-derived cultures, organoids and animal models to inform the HDCA, especially for prenatal tissues that are hard to acquire. Finally, we provide a roadmap towards a complete atlas of human development.
The treatment of patients with advanced acute heart failure is still challenging.
Intra-aortic balloon pump (IABP) has widely been used in the management of
patients with cardiogenic shock. However, according to international guidelines, its
routinary use in patients with cardiogenic shock is not recommended. This recommendation is derived from the results of the IABP-SHOCK II trial, which demonstrated
that IABP does not reduce all-cause mortality in patients with acute myocardial infarction and cardiogenic shock. The present position paper, released by the Italian
Association of Hospital Cardiologists, reviews the available data derived from clinical
studies. It also provides practical recommendations for the optimal use of IABP in
the treatment of cardiogenic shock and advanced acute heart failure.
Left ventricular false tendons (LVFTs) are fibromuscular
structures, connecting the left ventricular
free wall or papillary muscle and the ventricular
septum.
There is some discussion about safety issues during
intense exercise in athletes with LVFTs, as these
bands have been associated with ventricular arrhythmias
and abnormal cardiac remodelling. However,
presence of LVFTs appears to be much more common
than previously noted as imaging techniques
have improved and the association between LVFTs
and abnormal remodelling could very well be explained
by better visibility in a dilated left ventricular
lumen.
Although LVFTsmay result in electrocardiographic abnormalities
and could form a substrate for ventricular
arrhythmias, it should be considered as a normal
anatomic variant. Persons with LVFTs do not appear
to have increased risk for ventricular arrhythmias or
sudden cardiac death.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Basavarajeeyam is a Sreshta Sangraha grantha (Compiled book ), written by Neelkanta kotturu Basavaraja Virachita. It contains 25 Prakaranas, First 24 Chapters related to Rogas& 25th to Rasadravyas.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
ABDOMINAL TRAUMA in pediatrics part one.drhasanrajab
Abdominal trauma in pediatrics refers to injuries or damage to the abdominal organs in children. It can occur due to various causes such as falls, motor vehicle accidents, sports-related injuries, and physical abuse. Children are more vulnerable to abdominal trauma due to their unique anatomical and physiological characteristics. Signs and symptoms include abdominal pain, tenderness, distension, vomiting, and signs of shock. Diagnosis involves physical examination, imaging studies, and laboratory tests. Management depends on the severity and may involve conservative treatment or surgical intervention. Prevention is crucial in reducing the incidence of abdominal trauma in children.
share - Lions, tigers, AI and health misinformation, oh my!.pptxTina Purnat
• Pitfalls and pivots needed to use AI effectively in public health
• Evidence-based strategies to address health misinformation effectively
• Building trust with communities online and offline
• Equipping health professionals to address questions, concerns and health misinformation
• Assessing risk and mitigating harm from adverse health narratives in communities, health workforce and health system
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
2. Background
• The earliest steps
– Three germ layers—ectoderm, endoderm, and mesoderm
• Cardiogenic field on two sides
– Mesenchymal cell at anterior part
• Cardiogenic field meet in midline to form cardic
• Cardiogenic fields can be subdivided into two groups
– First heart field[Anterior)-future RT ventricle
– Second heart field[Posterior] –future left ventricle
• The two sides of the cardiac crescent fuse along the midline to form the primitive
heart tube
• The primitive heart tube can itself be subdivided into regions along the caudal to
rostral axis
– Sinus venosus
– Primitive atria
– Primitive ventricle
– Bulbus cordis (conus)
– Truncus arteriosus
• Heart beat at 5 weeks’ gestation
3. Earliest Development
Cardiovascular system makes its first appearance while the
embryo is still flat. Clusters of mesodermal cells specialise
to form blood cells. Mesodermal cells around these flatten
to form endothelium of blood vessels. These clusters are
called blood islands of angiogenic (“blood vessel-forming”)
cell clusters.
In the accompanying diagram note that these form a curve
reaching well beyond the neural plate and the notochord. A
mass of mesoderm, called cardiogenic area, near the head
end (H) will give rise to the heart.
The sagittal section below illustrates the three germ layers,
prochordal plate and the cardiogenic area.
H
Prochordal plate
Cardiogenic area
4. Head Fold
With the formation of the head fold (shown in the blue
circle), note how the cardiogenic area changes its
position. Also observe that the endoderm (yellow)
is beginning to form the gut tube. At this stage only
the head and tail ends of the digestive tube are
recognisable.
In the lowest picture, the gut tube is better seen and
the heart is in fact in the form of a tube (red).
Heart Tube
5. Heart
Liver
The Heart Tube
In the picture on the left the relationships of the
heart, the gut tube and the liver are clearer.
In the magnified picture of the heart tube, the tail
end is the venous end and the cranial end is the
arterial end. The changing shape of the tube
also makes it possible to recognise the primitive
chambers of the tube.
Remember that the tube is not partitioned at this
stage.
Hereafter, for descriptive convenience, we shall
view this tube in the vertical position, with the
caudal (venous) end below and the cranial
(arterial) end at the top as shown below.
6.
7. The Tube Bends
This picture shows three successive stages in the growth of the tube. The tube, as it grows,
cannot be accommodated within the pericardial cavity and undergoes bending.
The primitive chambers of the heart are recognisable, and are labelled in the last picture.
SV – sinus venosus (receives veins from the body), A – atrium, V – ventricle. The ventricle
continues into the ‘bulbus cordis’which in turn leads to the arterial end.
Two terms are used somewhat confusingly for the parts at the arterial end. These are
conus arteriosus and truncus arteriosus. In our discussion we shall simply say ‘arterial
end’ of the heart.
SV
A
V
BV D
8. Cardiac Looping
• Folds on itself and twists –looping
• Mechanism
– Differential ballooning out of the chambers
• D Loop- the looping occurs to the right
• The first visible sign of left-right
asymmetry
• Looping sets up the relationship between
the inflow tract, the outflow tract, and the
ventricular septum of the right ventricle
9. The Chambers
Recognise the chambers in these two views. In the view from the left side, the sinus
venosus is partly hidden. Note that with the bending of the tube the atrium is now dorsal
and the loop formed by the ventricle and the bulbus cordis (bulbo-ventricular loop) is
ventral.
In the next slide we shall examine the interior of the unpartitioned heart.
A
A A
V
B-V Loop
Left view Front view
10. The Interior
A portion of the ventral wall of the bulbo-
ventricular loop is removed to show the
interior.
Since there is no partition, there is a single
passage from the atrium to the ventricle.
This passage is the atrioventricular canal.
Note the direction of blood flow through
the bulboventricular loop.
Also note that the single vessel leading out of
the heart has given rise to what are called
aortic arches.
RA LA
AVC
A-Ar
11. Left – Right Partitioning
• Interatrial septum
• Interventricular septum
• Spiral (aortico-pulomonary) septum
• Endocardial cushions (A-V cushions)
• Functional requirements
• There must always be a right to left passage!
20. Sinus Venosus
• Originally a symmetrical structure
• Venous return more to the right
• Left horn becomes smaller
• Opening shifts to the right
• Later – part of right atrium
21. Left Atrium
• Four pulmonary veins
• Common opening
• “Absorption” of veins into atrium
• Rough part - auricle
23. Ventricular septum
• The primitive right ventricle is more anterior
• The flow of blood comes into the left ventricle, then goes across the
bulboventricular foramen to the right ventricle and out the as-yet-undivided
outflow tract. As development progresses, inflow becomes more directed
toward both ventricles
• Failure of this process can result in a double-inflow left ventricle [DILV]—a
situation much more common than double-inflow right ventricle
• The ventricular septum begins to grow toward the AV canal and outflow tract
from the apical and inferior portion of the junction between the primitive right
and left ventricle- muscular part of the interventricular septum
• Septation of the ventricle is complete when the muscular septum meets the
canal septum between the AV valves and the conal septum just below the
now separate outflow tracts
• The area at which these structures meet, there is the thinner membranous
septum.
28. Postnatal vs Foetal Circulation
• Postnatal
Body RA RV Lungs LA LV Body
• Foetal
Body RA RV Lungs LA LV Body
The basic difference between postnatal and foetal circulation is that foetal lungs are
nonfunctional. Effectively, blood from the right side of the heart has nowhere to go
and needs to be ‘shunted’ to the left. Such a shunting passage exists between the
right and the left atria. However, if no blood flows through the right ventricle, that
chamber will fail to develop. Thus some blood does pass to the RV. As it is pumped
into the pulmonary artery, it needs to be shunted again, this time to the aorta. This
illustrated below.
But we are jumping too far ahead! This was mentioned as one of the basic principles of
the development of the heart…let us begin at the beginning.
29. • IVC :
Blood from
placenta
– Ductus
venosus
• F. ovale
• Ductus
arteriosus
30. Changes At Birth
• Closure of interatrial septum
• Closure of ductus arteriosus
• Closure of ductus venosus