The cardiovascular system consists of the heart and blood vessels that circulate blood throughout the body. The heart has four chambers and uses valves to ensure one-way blood flow. It is regulated by the autonomic nervous system. During each cardiac cycle, the atria contract followed by ventricular contraction that pumps blood out of the heart into the arteries. Relaxation of the ventricles allows blood to flow back into the heart. The conductive system generates electrical signals that coordinate the heart's pumping action.
The cardiovascular system can be thought of as the transport system of the body.
This system has three main components: the heart, the blood vessel and the blood itself.
The heart is the system’s pump and the blood vessels are like the delivery routes.
This presentation is an overview of the description of the 4 stages of the cardiac cycle (atrial diastole, atrial systole, ventricular systole, ventricular diastole) as well as explaining the mechanism of the cardiac cycle.
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away from the tissues.
The cellular components of blood are erythrocytes (red blood cells, or RBCs), leukocytes (white blood cells, or WBCs), and thrombocytes (platelets). By volume, the RBCs constitute about 45% of whole blood, the plasma about 54.3%, and white blood cells about 0.7%. Platelets make up less than 1%.
The cardiovascular system can be thought of as the transport system of the body.
This system has three main components: the heart, the blood vessel and the blood itself.
The heart is the system’s pump and the blood vessels are like the delivery routes.
This presentation is an overview of the description of the 4 stages of the cardiac cycle (atrial diastole, atrial systole, ventricular systole, ventricular diastole) as well as explaining the mechanism of the cardiac cycle.
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away from the tissues.
The cellular components of blood are erythrocytes (red blood cells, or RBCs), leukocytes (white blood cells, or WBCs), and thrombocytes (platelets). By volume, the RBCs constitute about 45% of whole blood, the plasma about 54.3%, and white blood cells about 0.7%. Platelets make up less than 1%.
Cardiovascular physiology for university studentsItsOnyii
A detailed pdf document on cardiovascular physiology for university students including structure and functions of heart, Electrocardiogram, echocardiography, chest and limb leads, Diseases and disorders of the heart.
1 GNM - Anatomy unit - 4 - CVS by thirumurugan.pptxthiru murugan
By:M. Thiru murugan
Unit – IV:
Heart : Structure, functions including conduction system & cardiac cycle
Blood vessels : Types, Structure and position
Circulation of blood
Blood pressure and pulse
Heart
The circulatory system:
It consisting of blood, blood vessels, and heart.
This supplies oxygen and other nutrients,
Transports hormones
Removes unnecessary waste products.
Heart and its Structure
The heart is a muscular organ about the size of a fist,
located in mediastinum just behind and slightly left of the breastbone (sternum).
The heart pumps blood through the blood vessels (arteries and veins called the cardiovascular system).
Structure of heart:
Layers of the heart (3)
Chambers of the heart (4)
Valves of the heart (4)
Blood vessels of the heart (5)
3 layers of the heart:
Epicardium/pericardium: outer protective layer of the heart. Visceral and parietal (pericardial fluid). Protection for the heart and big vessels and prevent collapse of heart,
Myocardium: muscular middle layer wall of the heart. Responsible for keeping the heart pumping blood around the body.
Endocardium: the inner layer of the heart. Regulate blood flow through the chambers of the heart and pass the electrical impulses
Chambers of the heart:
The atria: These are the 2 upper chambers, which receive blood. RA / LA
The ventricles: These are the 2 lower chambers, which discharge blood. RV/ LV
A wall of tissue called the septum separates the left and right atria called atrial septum and the left and right ventricle called ventricular septum.
Valves in the heart:
There are four valves
Two-atrio ventricular valves: The 2 types: bicuspid (mitral) - LA & LV, and tricuspid valves - RA & RV.
Two-semilunar valves: The aortic valves and the pulmonary valve.
Major blood vessels of the heart
There are 5 major blood vessels
Pulmonary artery
Pulmonary veins
Aorta[artery]
Inferior vena cava [IVC] veins
Superior vena cava [SVC] veins
Functions of heart:
Pumping oxygenated blood to the body parts.
Pumping nutrients and other vital substances
Receiving deoxygenated blood and carrying metabolic waste products from the body
Pumping deoxygenated blood to the lungs for oxygenation.
Maintaining blood pressure.
Conduction system
The electrical conduction system that controls the heart rate.
This system generates electrical impulses and conducts them throughout the muscle of the heart, stimulating the heart to contract and pump blood.
The electrical pulses determine the order in which the chambers contract & the heart rate
Conductive system consist of:
SA Node
AV Node
Bundle of his or His Bundles – bundle of branches
( right and left)
4. Purkinje fibres
Sinoatrial node (SA) : also known as the pace maker of the heart and Located in the upper wall of the right atrium
Made up of both muscle and nervous tissue
Here the electrical impulse begins
Atrioventricular (AV) node:
located between the atria and ventricles of the heart
The electrical impulse is carried fr
The heart has four chambers. The two superior receiving chambers are the atria (= entry halls or chambers), and the two inferior pumping chambers are the ventricles (= little bellies).
On the anterior surface of each atrium is a wrinkled pouchlike structure called an auricle
This system has three main components: the heart, the blood vessel and the blood itself. The heart is the system's pump and the blood vessels are like the delivery routes. Blood can be thought of as a fluid which contains the oxygen and nutrients the body needs and carries the wastes which need to be removed.
Sense Organ - Nose - Anatomy of Nose & Physiology of Olfaction, For Medical and Paramedical students, B.Pharm, Pharm.D, D.Pharm, Human Anatomy & Physiology
III Pharm.D - The Dynamic Cell - III Pharm.D - The Dynamic Cell - Cellular cl...Kameshwaran Sugavanam
III Pharm.D -Pharmacology II - The Dynamic Cell - III Pharm.D - The Dynamic Cell - Cellular classification, subcellular organelles ppt. As per PCI syllabus
III year Pharm.D - Pharmacology -II - "Chromosome structure: Pro and eukaryotic chromosome
structures, chromatin structure, genome complexity, the flow of
genetic information"
INTRODUCTION TO HUMAN BODY - Definition and scope of anatomy and physiology, ...Kameshwaran Sugavanam
INTRODUCTION TO HUMAN BODY - Definition and scope of anatomy and physiology, levels of structural organization and body systems, basic life processes, homeostasis,
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
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
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
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
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- 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
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
3. Functions of the cardio vascular system:
• Distribution of oxygen and nutrients to
all the body parts
• Transportation of CO2 and metabolic
waste products from tissues to lungs
and other excretory organs
• Distribution of water electrolytes and
hormones through out the body
• Part of immune system
• Thermoregulation
4. Heart
• Blood pumped through the muscular
organ called heart
• It is composed of strong cardiac muscle
tissue
• Shows rhythmic contraction and
relaxation
• Due to this blood pumped to the entire
body along with nutrients and oxygen
5. ANATOMY OF HEART:
• Heart is a muscular organ
• Size is about closed fist
• Average weight –
female – 250-300gms, Male – 300-350gms
• Average human heart beats 70-72 times per
minute
• Situated in the thoracic cavity – in the
mediastinum space, just above the diaphragm
• Present at the level of thoracic vertebrae T5-T8
• Present in the midline just tilted towards the left
• It is a rounded cone shaped structure
7. Walls of the Heart
• Pericardium – loose fitting sac surrounding the
heart
• EPICARDIUM
• MYOCARDIUM
• ENDOCARDIUM
8. Epicardium: outer layer of heart
Consist of 2 layers
– Fibrous pericardium – tough, loose-
fitting, inelastic
– Serous pericardium
• Parietal layer: lines the inside of the
fibrous pericardium
• Visceral layer: adheres to outside of
the heart
– Pericardial space: between parietal
and visceral layer
• Filled with 10-15mL of pericardial fluid
• Decreases friction
9.
10. Myocardium:
• It is the thickest layer
• contractile layer composed of cardiac muscle
cells
• Cardiac muscle is striated, involuntary, and
branched
• Heart contracts by contraction of myocardial
membrane
Endocardium:
• – inner most and third layer of heart wall
– Consist thin layer of specialized epithelial tissue
(Endothelium)
– Covers inner layers of heart and provides smooth
flow of blood inside the heart
11. Chambers of the Heart
• Heart is a hollow chamber
• Divided in to 4 different chambers
Atria – two superior chambers
– “Receiving chambers”
– Thin walled low pressure chambers
– Blood from superior vena cava & Inferior vena
cava enters atria
Ventricles – two inferior chambers
– “pumping chambers”
– Thick walled high pressure chamber
– Thick muscular walls to increase force of
pumping action
– Left & right venticles Separated by
interventricular septum
12. Valves of the Heart
“Permit blood flow in one direction
during circulation”
• Atrioventricular valves (AV valves)
– Also cuspid valves
– Between atria and ventricles
• Semilunar (SL valves)
– Between R ventricle and pulmonary
arteries and L ventricle and aorta
13. Atrioventricular Valves
Tricuspid valve
– Between R atrium and ventricle
– 3 flaps of endocardium
– Connected to ventricular papillary muscle
via chordae tendinea
Bicuspid valve
– Between L atrium and ventricle
– Also called mitral valve
– Two flaps of endocardium
– Connected to ventricular papillary muscle
via chordae tendinea
14.
15. Semilunar Valves
• Pulmonary semilunar valve
– Btwn R ventricle and pulmonary trunk
• Aorta semilunar valve
– Btwn L ventricle and aorta
17. Blood Supply to the Heart
• To work efficiently the heart needs a continues
blood supply
• Needs to supply oxygen and nutrients and to
remove the waste materials
• Heart has its own system of circulation – coronary
circulation
• Left and right coronary arteries arises at the base
of aorta
• From there they supply the blood to right and left
side of heart
• Coronary artery provides – pure blood
• Coronary vein – remove waste products
• Coronary sinus – empties the deoxygenated blood in
to the right atrium
18.
19. CONDUCTION SYSTEM OF THE HEART
Conduction system of heart includes 6 components
• SINOATRIL (SA) NODE
• INTERNODAL PATHWAYS
• ATRIOVENTRICULAAR (AV) NODE
• BUNDLE OF HIS
• BUNDLE BRANCHES
• PURKINJIE FIBRES
20.
21. • Sinoatrial Node (SA Node)
– It is located it right atrium – near the
opening of superior vena cava.
– It is 1.5cm length & 0.5cm width
– It is also known as Pacemaker of the heart
– It comprises of pacemaker cells (P) & some
myofilaments
– Impulse is generated by the P cells and
transmitted with in the conducting system
for the excitation and contraction of heart
muscles
22. INTERNODAL PATHWAYS:
• They connect SA node and AV node
• They are
– Anterior internodal pathway
– Middle internodal pathway
– Posterior internodal pathway
23. ATRIOVENTRICULAAR (AV) NODE
• It is located in the lower part of the right atrium
• Close to the interatrial septum
• It is 2.2cm long 10mm wide and 3 mm thick
• The pacemaker (P) cells are also present in the AV node
• Impulse formation is slower in AV node than SA node
24. BUNDLE OF HIS:
• A small fibre bundle arising from the AV node
and terminating in the purkinje system
- Bundle of His
It is located beneath the AV node and passes
towards the interventricular septum
It is about 1 cm in length
Left branch bundle & Right branch bundle
In case of non functioning SA & AV node
impulse generated by Bundle of His
25.
26. BUNDLE BRANCHES:
“The branches of bundle fibres enters the walls
of the ventricle to further branch out in to very
small fibre bundles – further branch in to very
small fibre“ – Purkinje fibres
The bundle branches also have ability to
generate impulses
2 types:
Right bundle branch &
Left Bundle branch
27. PURKINJE FIBRES:
• The fibres forms a network of small
bundle of conducting fibres
• They are located all over the sub
endocardial regions of R&L ventricles
28. PATHWAY OF NERVE IMPULSE
SA NODE
↓
INTERNODAL PATHWAY
↓
AV NODE
↓
BUNDLE OF HIS
↓
RIGHT AND LEFT BUNDLE BRANCHES
↓
PURKINJE FIBRES
↓
VENTRICULAR MYOCYTES
29. REGULATION OF HEART BY ANS
The centre for regulation of the heart is
CARDIOVASCULAR CENTRE
Which is present in the medulla oblongata
It receives input from
Sensory receptor
Higher centre of brain
The cardiac output is maintained either by
increasing or decreasing the frequency of
nerve impulses in the ANS – increase or
decrease cardiac output.
30. • Sympathetic Neurons (thoracic region of spinal
cord) – release - Nor-Epinephrine – acts on -
muscle fiber of heart – produces 2 effects
• Increases heart rate – by increasing the rate of
spontaneous depolarization in SA node, AV
Node & cardiac muscle fibers
• Increases contractility – by increasing entry of
Ca2+ ions through voltage gated calcium
channels present in the contractile fibers
• Maximum synthetic stimulation can be
200pulse per min
31. PARA SYMPATHETIC NEURONS:
• Reaches heart via Xth cranial nerve
(vagus)
• Releases acetylcholine – act on muscle
fibers of heart – decreases HR by
decreasing the rate of spontaneous
depolarization in cardiac muscle fibres
• The heart can slow to 20-30 beats/Min
32.
33.
34. PHYSIOLOGY OF HEART:
• The heart has four separate chambers.
• The upper chamber on each side of the heart, which is
called an atrium - receives and collects the blood
coming to the heart.
• The atrium then delivers blood to the powerful lower
chamber, called a ventricle - which pumps blood away
from the heart through powerful, rhythmic contractions.
35. • The human heart doing two pumps in
one.
• The right side receives oxygen-poor
blood from the various regions of the
body and delivers it to the lungs.
• In the lungs - oxygen is absorbed in the
blood.
• The left side of the heart receives the
oxygen-rich blood from the lungs and
delivers it to the rest of the body.
36. Cardiac cells
• Cardiac cells are cylindrical in shape
• It is arranged such if one cell is stimulated it
stimulates the adjacent cell
Two types of cardiac cells
• Electrical cells & Myocardial cells
Electrical cells - Specialized cell
• This cell cannot able to contract but can
conduct the nerve impulse
• Electrical impulse – produced in SA Node –
forwarded to rest of the heart – force of
contraction is generated – pumps the blood.
37. ACTION POTENTIAL
• Resting membrane potential at the heart
is – 90mV
• Sudden influx of Na+ Ions in cardiac
membrane – initiates action potential in
myocardial cell
- Phase 0/ Upstroke of action potential
• outward movement of K+ ions – initial
phase of repolarization – 1st phase of
action potential
38. Increase in the Inward movement of Ca2+
ions and outward movement of K+ ions
- 2nd Phase/ plateau phase
Inward movement of calcium ions
(decreasing)& outward movement of
potassium ions (increasing)
- 3rd phase/ phase of repolarization
The potassium ions concentration becomes
equilibrium by the outward conduction of
potassium ions in the third phase
-4th Phase/ Phase of repolarization
39.
40.
41. CARDIAC CYCLE
“Rhythmic Pumping of Heart”
Contraction and relaxation occurring during the
one heart beat – cardiac cycle
Phases of Cardiac Cycle
1. Systole – contraction
2. Diastole – relaxation
• At a normal heart rate, one cardiac cycle last for 0.8
seconds!
42. • “One contraction (systole) and one
relaxation (diastole) of auricles and
ventricles resulting in one heart beat”
» - known as CARDIAC CYCLE
SYSTOLE:
• A significant pumping of blood from the
cardiac chamber
DIASTOLE:
• Significant entry of blood in to the cardiac
chamber
43. Stages of cardiac cycle:
4 stages:
• ATRIAL SYSTOLE
• VENTRICULAR SYSTOLE
• VENTRICULAR DIASTOLE
• JOINT DIASTOLE
ATRIAL SYSTOLE:
This is marked by stimulation of SA node
A wave of contraction spreads through atria and
bicuspide and tricuspid valves open up
Which pumps blood from atria in to ventricles
44. VENTRICULAR SYSTOLE:
• Contraction of ventricles occurs as the
wave of contraction spreads through
both the ventricles
• This is stimulated by AV node stimulation
• The bi & tri cuspid valves close and
produce the first heart sound – LUB
• The sound lasting for 0.16-0.90 sec
• As the ventricle contracts blood flows
into dorsal aorta from left ventricle &
pulmonary artery from right ventricle
45. VENTRICULAR DIASTOLE:
• As ventricles relax both semilunar valves
closes with a sound of – DUB
• Pressure with in the ventricles decreases
continuously
• When the pressure falls below the
pressure of atrium both bicuspid and
tricuspid valves open and the blood again
flows in to the ventricles
46. JOINT DIASTOLE:
• Before the cycle starts again, both the atria and
ventricles are relaxed
- JOINT DIASTOLE
During this state blood flows from superior and
inferior vena cava into the atria & atria to ventricles
Duration of cardiac cycle: 0.88 Sec
Which can be divided as
Auricular systole - 0.18 Sec
Auricular diastole - 0.08 sec
Ventricular systole - 0.30 sec
Ventricular diastole - 0.32 sec
47. CARDIAC OUTPUT:
“The amount of blood flowing from the heart ( from left
ventricle in to aorta) in one heart beat”
Cardiac output = stroke volume x Heart rate
= 70ml x 72/min
= 5040 ml/min
= about 5 liters/ min
Stroke volume = volume of blood pumped by heart per
heart beat
Heart rate = ventricular systole / min
48. PULSE:
“A wave of distension felt in the arteries with
each heartbeat “
It is counted from radial artery of the wrist
Pulse rate normally is the same as the heart
rate
Tachycardia – increase in the pulse/ heart rate
over 100 beats/min
Bradycardia – decrease in the heart/pulse rate
under 50 beats/ min
Normal pulse rate – 70-90 per minute
Men – 72/min, women – 80/min
49. ELECTRO CARDIOGRAM (ECG)
Electrical current generated in the heart by the
propagation of action potential can be detected
on the surface of the body as electrical signals
These changing signals are recorded by an
instrument – Electrocardigram (ECG)
ECG – composite record of action potentials
produced by the heart muscles
Recording done by using electrodes – helps in
detection of cardiac abnormalities
50.
51. There are 3 recognizable waves
– P wave
– QRS complex
– T wave
P WAVE:
This is first wave spreading from SA node
through contractile fibres in both atria
Representing atrial depolarisation
It is seen as a small upward deflection on
ECG
52. QRS COMPLEX
• this is the second wave
• Occurs due to action potential spreadds
through ventricular contractile fibres
• Representing rapid ventricular
depolarisation
• It continues as large upright, triangular
wave
• Beginning as downward deflection and
ending as downward wave
53. T WAVE:
• This is the third wave
• Its seen when ventricle relax
• Indicating ventricular repolarisation
• Appear as dome shaped upward
deflection
• Smaller and wider than QRS complex
• This is due to the slower repolarisation
than the depolarisation
54. • Size of each wave appearing on ECG helps
in interpreting any abnormality
• Larger P wave – Enlarged atrium
• Large Q wave – possible myocardial infarction
• Large R wave – Enlargement of ventricles
• Flatter T wave – insufficient O2 supply to cardiac
muscles
• Elevated T wave – high level of K+ in the blood
55. Analysis of ECG:
• Intervals or segments are the time spans
present between the waves
• This helps in analyzing an ECG
• P-Q INTERVAL
• S-T SEGMENT
• Q-T INTERVALS
56. BLOOD PRESSURE
“BLOOD PRESSURE (BP) IS THE PRESSURE OF
CIRCULATING BLOOD ON THE WALLS OF BLOOD
VESSELS”
Normal blood pressure has high systolic value and low
diastole value 120mm Hg/ 80mm Hg in arteries
The blood pressure is measured by sphygmomanometer
57. Types of blood pressure:
Arterial blood pressure may be of 4 types
Systolic pressure :
maximum pressure exerted during systole of the heart
when LV contact & pump blood to aorta),
Normal value: 120mm Hg
Occurs in the beginning of the cardiac cycle
Diastolic pressure:
it is the minimum pressure on the arteries
Normal value: 90mm Hg
It occurs at the end of the cardiac cycle
When V is in resting phase after pumping blood
Pulse pressure: it is differential pressure of systolic and
diastolic pressure – 40mm Hg
Mean atrial pressure – average pressure on the arteries
58. REGULATION OF BLOOD PRESSURE:
SHORT TERM REGULATION OF BLOOD PRESSURE:
• BARORECEPTOR REFLEXES
• CHEMORECEPTOR REFLEXES
• CNS ISHCHAEMIC RESPONSE
• SHIFT OF CAPILLARY FLUID
LONG TERM REGULATION OF BLOOD PRESSURE
• REGULATION OF VOLUME OF EXTRACELLULAR
FLUID
• RENIN- ANGIOTENSIN MECHANISM
HORMONAL CONTROL
59. Baroreceptors reflex:
Baroreceptors are receptors found in carotid
sinus & aortic arch.
They are stimulated by changes in BP.
BP
+ Baroreceptors
Stimulate
Para Sympathetic nerve
Stimulate
Sympathetic nerve
Heart contractility &
vasoconstriction
Heart contractility &
vasoconstriction
Decrease in blood pressure
Increase in blood pressure
60. Chemoreceptors reflex:
■ Chemoreceptors are receptors found in carotid &
aortic bodies.
■ they are stimulated by chemical changes in blood
mainly - hypoxia ( O2), hypercapnia ( CO2), & pH
changes.
Chemoreceptors
Vasomotor centre
in heart rate & stroke volume
Decreased partial pressure of oxygen
Increase in the blood pressure
Increased partial pressure of oxygen
61. CNS ISHCHAEMIC RESPONSE
If the blood pressure reduces to less than 50mm Hg &
Increased partial pressure of CO2
Vasomotor centre stimulated by this
Increase in the sympathetic activity
Increases heart rate
BP turns to normal
62. Shift of capillary fluid:
• Capillary pressure is directly
proportional to arterial pressure
• When arterial pressure is more the fluid
present in the capillaries start passing
out to the capillary
• Automatically blood pressure comes to
normal
63. LONG TERM REGULATION OF BLOOD
• Regulation of volume of extracellular fluid:
Increase in volume of extra cellular fluid
↓
Which increases blood volume
↓
Thus increases arterial blood pressure
↓
The kidney excrete excess amount of water and salt
↓
There by reducing the ECF volume
↓
Brings the blood pressure to the normal
64. RENIN – ANGIOTENSIN MECHANISM:
Hypotension
↓
Low blood flow to the kidney
↓
Secretes renin
↓
Renin converts Angiotensinogen to Angiotensin-I
↓
ACE- converts Angiotensin-I to Angiotensin-II
↓
Angiotensin-II is potent vasoconstrictor
↓
Increase Blood Pressure
65. HORMONAL CONTROL
Hormones may increase or decrease blood
pressure
THYROXIN:
increases systolic blood pressure
Reduces diastolic blood pressure
ANGIOTENSIN & SERATONIN:
Increases blood pressure by vasoconstriction
BRADYKININ & ACETYLCHOLINE:
Reduces BP by vasodilatation
66. DISORDERS OF HEART:
• Coronary heart disease – affect coronary blood vessel
• Rhuematic heart disease – damage to heart muscle & valve
• Congenital heart disease – due to genetic factor deformities of heart
structure
• Stroke: interruption of blood supply to brain
• Peripheral artery disease (PAD) – Plaque in peripheral artery ( supply
blood to limbs & heart)
• Deep vein thrombosis - blood clots in the vein – carried to the heart
• pulmonary embolism – blood clots in the vein – carried to the lungs
Hypertension – High blood pressure > 140/90mm Hg
Hypotension – Low blood pressure < 90/60 mm Hg
• Angina pectoris – chest pain - decreased blood supply to heart
• Myocardial ischemia – imbalance btn supply and demand of oxygen
• Myocardial infarction – due to loss of blood supply – death of heart cell
• Congestive heart failure – heart fails to pump blood from ventricle
• Cardiac arrhythmia – irregularities in cardiac rhytham
• Arteriosclerosis – formation of fibrofatty plaques in tunica intima layer
of arteries