Describe events in cardiac cycle.
Describe atrial, ventricular and aortic pressure changes during cardiac cycle.
Describe the changes in ventricular volume & stroke volume during cardiac cycle.
Relate ECG changes to the phases of cardiac cycle.
Describe the functions of cardiac valves and relate their state to the production of heart sounds during cardiac cycle.
med_students0
Describe events in cardiac cycle.
Describe atrial, ventricular and aortic pressure changes during cardiac cycle.
Describe the changes in ventricular volume & stroke volume during cardiac cycle.
Relate ECG changes to the phases of cardiac cycle.
Describe the functions of cardiac valves and relate their state to the production of heart sounds during cardiac cycle.
med_students0
Cardiac cycle refers to a complete heartbeat from its generation to the beginning of the next beat.
Cardiac events that occur from –
beginning of one heart beat to the beginning of the next are called the cardiac cycle.
Right Atrium of human heart
This PPT help to understand the external and internal structures of right atrium.
sulcus terminalis on external surface of rt atrium,
crista terminalis on internal side of rt. atrium,
interior is divided into rough anterior part and smooth posterior part ( sinus venarum)
superior and inferior venae cavae drains deoxygenated blood into rt. atrim
there is Eustachian valve to guard the opening of IVC and Thebesian valve to guard the opening of coronary sinus
septal wall presents fossa ovalis with its border limbus fossa ovalis
Cardiac cycle (The Guyton and Hall physiology)Maryam Fida
Sequence of events from the beginning of one systole to the beginning of next consecutive systole.
One heart beat consists of one systole and one diastole.
Each cardiac cycle is initiated by the cardiac impulse which originates from the SA node.
During each cardiac cycle, certain events occur in the heart and these include pressure changes, volume changes, production of heart sounds, closure and opening of heart valves and electrical changes in the heart.
HEART RATE
REGULATION OF HEART RATE
VASOMOTOR CENTER – CARDIAC CENTER
MOTOR (EFFERENT) NERVE FIBERS TO HEART
FACTORS AFFECTING VASOMOTOR CENTER
for all medical & health care students
Cardiac cycle refers to a complete heartbeat from its generation to the beginning of the next beat.
Cardiac events that occur from –
beginning of one heart beat to the beginning of the next are called the cardiac cycle.
Right Atrium of human heart
This PPT help to understand the external and internal structures of right atrium.
sulcus terminalis on external surface of rt atrium,
crista terminalis on internal side of rt. atrium,
interior is divided into rough anterior part and smooth posterior part ( sinus venarum)
superior and inferior venae cavae drains deoxygenated blood into rt. atrim
there is Eustachian valve to guard the opening of IVC and Thebesian valve to guard the opening of coronary sinus
septal wall presents fossa ovalis with its border limbus fossa ovalis
Cardiac cycle (The Guyton and Hall physiology)Maryam Fida
Sequence of events from the beginning of one systole to the beginning of next consecutive systole.
One heart beat consists of one systole and one diastole.
Each cardiac cycle is initiated by the cardiac impulse which originates from the SA node.
During each cardiac cycle, certain events occur in the heart and these include pressure changes, volume changes, production of heart sounds, closure and opening of heart valves and electrical changes in the heart.
HEART RATE
REGULATION OF HEART RATE
VASOMOTOR CENTER – CARDIAC CENTER
MOTOR (EFFERENT) NERVE FIBERS TO HEART
FACTORS AFFECTING VASOMOTOR CENTER
for all medical & health care students
Medical science of cardiovascular system. It is the importance system in the human body. Blood is a specialised fruit can keep tissue which is circulated by cardiovascular system. Other system are respiratory system nervous system, gastrointestinal system . But cardiovascular system is the important system in our human body. Which involved heart
Useful for medical and biology students who want to study the cardiac cycle in a short time with big benefits !!
CVS physiology - Wigger Diagram - ECG of cardiac cycle - Heart sounds
CARDIAC CYCLE, ECG AND HEART SOUNDS.pptxthiru murugan
CARDIAC CYCLE, ECG AND HEART SOUNDS: BY Wincy Thirumurugan..
“Cardiac cycle refers to the series of events that take place when the heart beats.”
Each cycle is initiated by spontaneous contraction in the SA node and then transmit through the A-V bundle and branches into the ventricles results completion of one cycle.
EVENTS OR PHASES OF CARDIAC CYCLE: Diastolic phase (Diastole) in this phase the heart chamber are in the state of relaxation and fills with blood that receives from the veins [IVC, SVC,PULMONARY VEINS]
Systolic phase (Systole) in this the heart chambers are contracting and pumps the blood towards the periphery via the arteries. [ Pulmonary artery and aorta]
PHASES OF THE CARDIAC CYCLE
The different phases of the cardiac cycle involve:
Atrial diastole - Atrial relaxation
Atrial systole -Atrial contraction
Isovolumic relaxation -ventricular relaxation in the early phase but blood will not move and the Atrio ventricular valves will be closed
Ventricular filling - ventricular relaxation, the Atrio ventricular valves will be open allows filling blood in the ventricles
Isovolumic contraction of ventricle – ventricular systole in the early phase but no movement of the blood. The semilunar valves will be closed.
Ventricular ejection -ventricular contraction and send blood out of the ventricles through opened semilunar valves.
6. Ventricular Filling Stage: second phase. Rapid Filling, Slow Filling & Last Rapid Filling Duration of Cardiac Cycle:
In a normal person, a heartbeat is 72 beats/minute.
An Electrocardiogram (ECG) is a medical test that detects cardiac (heart) abnormalities by measuring the electrical activity generated by the heart as it. The machine that records the patient’s ECG is called an electrocardiograph.
contracts.
PLACEMENT OF ECG LEADS
ECG WAVES:
The P wave is caused by spread of depolarization through the atria, After the onset of the P wave, The QRS waves Occurs as a result of electrical depolarization of the ventricles, the ventricular T wave represents the stage of repolarization of the ventricles, The 'U' wave is a wave comes after the T wave of ventricular repolarization and may not always be observed.
HEART SOUNDS: First Heart Sound (S1)
The first heart sound results from the closing of the mitral and tricuspid valves. Second Heart Sound (S2): The second heart sound is produced by the closure of the aortic and pulmonic valves. Third Heart Sound (S3):
The third heart sound, also known as the “ventricular gallop,” occurs just after S2 when the mitral valve opens, allowing passive filling of the left ventricle. The S3 sound is actually produced by the large amount of blood striking a very compliant LV.
[Compliance heart means how easily the chamber of heart or the lumen of blood vessels expands when it is filling with the blood]
Fourth Heart Sound (S4):
The fourth heart sound, also known as the “atrial gallop,” occurs just before S1 when the atria contract to force blood into the LV.
Cardiac cycle and how the different chambers of the heart fill. We talk about the ventricular fillings and how diastole and systole work.
How pressure changes during all cycles
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
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
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.
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
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
Title: Sense of Taste
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 structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
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
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
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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.
Ocular injury ppt Upendra pal optometrist upums saifai etawah
Cardiac cycle made easy
1. Cardiac Cycle
Dr. Md. Mostafizur Rahman Bhuiyan
Resident (Phase: A)
Dept. of Paediatric Cardiology
2. Definition:
The cardiac events that
occur from the beginning
of one heartbeat to the
beginning of the next are
called the cardiac cycle.
Cardiac Cycle
3. Events in cardiac cycle :
Electrocardiogram
Mechanical changes
Atrial systole & diastole
Ventricular systole & diastole
Pressure Changes
Aortic pressure
Ventricular pressure
Atrial pressure
Pulmonary artery pressure
Volume changes
Heart sounds
A Wiggers diagram, named after its developer, Dr. Carl J. Wiggers, is a standard diagram
used in teaching cardiac physiology. In the Wiggers diagram, the X axis is used to plot time,
while the Y axis contains all of the following on a single grid.
4.
5. Relationship of the Electrocardiogram
to the Cardiac Cycle
• Each cardiac cycle is initiated by
spontaneous generation of an action
potential in the SA node.
The P wave
Is caused by spread of depolarization
through the atria
It is followed by atrial contraction
It causes a slight rise in the atrial
pressure curve immediately after the P
wave.
About 0.16 s after the P wave, the QRS
appear
6. Relationship of the Electrocardiogram
to the Cardiac Cycle
QRS complex:
• Caused by electrical depolarization of
the ventricles
• It initiates contraction of the ventricles
i.e ventricular systole
T wave:
• It represents the stage of repolarization
of the ventricles when the ventricular
muscle fibers begin to relax.
• Therefore, the T wave occurs slightly
before the end of ventricular
contraction.
7. • A-V Valves Open; Semilunar Valves Closed
• Atrial systole (1): About 80% of blood normally
flows continually from the great veins into the
atria. Then, atrial contraction causes an
additional 20% filling of the ventricles.
• Atrial diastole : At the end of systole diastole
occurs and during this period blood enters into
atria from great veins.
• Atrial systole occurs during the last phase of
ventricular diastole. Atrial diastole is not
considered as a separate phase, since it
coincides with the whole of ventricular systole
and earlier part of ventricular diastole.
Mechanical events in Cardiac cycle
8. • Ventricular systole: starts at the
end of atrial sytole.
• Isovolumic contraction (2):
– Immediately after ventricular
contraction begins, the ventricular
pressure rises abruptly, causing the
A-V valves to close, produces the
1st heart sound
– during this period, ventricle
contracts but muscle does not
shorten and no blood passes out of
ventricle, thus pressure increases.
– It strarts from the closure of AV
valve and terminated by opening
of semilunar valve
9. • Period of rapid ejection (3) : the first third
of ejection is called the period of rapid
ejection as 70 per cent of the blood
emptying occurring during this time.
• Period of slow ejection (4): remaining 30
per cent emptying occurs during the last
two third of cardiac cycle known as the
period of slow ejection.
Period of Ejection:
When the left ventricular pressure rises slightly
above 80 mm Hg (and the right ventricular
pressure slightly above 8 mm Hg), the
ventricular pressures push the semilunar
valves open. Immediately, blood begins to
pour out of the ventricles.
10. • Ventricular diastole:
• Protodiastolic phase :
– pressure in ventricles
falls
– semilunar valve closes
due to high aortic
pressure
– produces 2nd heart
sound
11. Isovolumic relaxation (5) :
• interval between closure of semilunar valve and
opening of AV valve
• At the end of systole, ventricular relaxation begins
suddenly, allowing both the right and left
intraventricular pressures to decrease rapidly.
• The elevated pressures in the distended large
arteries that have just been filled with blood from
the contracted ventricles immediately push blood
back toward the ventricles, which snaps the aortic
and pulmonary valves closed.
• For another 0.03 to 0.06 second, the ventricular
muscle continues to relax, even though the
ventricular volume does not change, giving rise to
the period of isovolumic or isometric relaxation.
• During this period, the intraventricular pressures
decrease rapidly back to their low diastolic levels.
• Then the A-V valves open to begin a new cycle of
ventricular pumping.
12. • Rapid filling phase(6):
– ventricular pressure fall markedly and the
blood rushes from atria to ventricle.
• Blood was accumulated in the rt & lt atria during
ventricular systole for the closed A-V valves &
the moderately increased atrial pressure push
the A-V valves open and allow blood to flow
rapidly into the ventricles
– 3rd heart sound produces
• Slow filling phase /diastasis (7):
– amount of filling is minimum (blood from
the veins and passes through the atria
directly into the ventricles)
– ventricular pressure slowly rises
• Last rapid filling (Atrial systole):
– due to atrial contraction blood rushes from
atria to ventricle. It accounts for about 20
per cent of the filling of the ventricles during
each cardiac cycle.
13. Mechanical events in Cardiac cycle
DIVISIONS AND DURATION OF CARDIAC CYCLE
When the heart beats at a normal rate of 72/minute, duration of each cardiac cycle is about 0.8 second.
ATRIAL EVENTS Time VENTRICULAR EVENTS Time
Atrial systole 0.11
(0.1)
Ventricular systole 0.27
(0.3)
1.Isovolumetric
contraction
0.05
2. Ejection period 0.22
Atrial diastole
=
0.69
(0.7)
Ventricular diastole 0.53
(0.5)
1. Protodiastole 0.04
2. Isometric relaxation 0.08
3. Rapid filling 0.11
4. Slow filling /
diastasis
0.19
5. atrial systole / Last
rapid filling
0.11
14. Atrial Events Vs
Ventricular Events
• Out of 0.7 sec of atrial diastole, first
0.3 sec (0.27 sec accurately)
coincides with ventricular systole.
• Then, ventricular diastole starts and
it lasts for about 0.5 sec (0.53 sec
accurately).
• Later part of atrial diastole
coincides with ventricular diastole
for about 0.4 sec. So, the heart
relaxes as a whole for 0.4 sec.
15. Pressure Changes in the Atria
In the atrial pressure curve three minor elevations, called the
a, c, and v atrial pressure waves, are noted.
The a wave
• caused by atrial contraction.
• right atrial pressure increases 4 to 6 mm Hg during
atrial contraction, and the left atrial pressure
increases about 7 to 8 mm Hg.
The c wave
• occurs when the ventricles begin to contract;
• it is caused partly by slight backflow of blood into
the atria at the onset of ventricular contraction
• and mainly by bulging of the A-V valves backward
toward the atria because of increasing pressure in
the ventricles.
The v wave
• occurs toward the end of ventricular contraction;
it results from slow flow of blood into the atria
from the veins while the A-V valves are closed
during ventricular contraction
16. Pressure change in Ventricle:
Intra ventricular Pressure Change During
Ventricular Systole:
• When the heart is in diastole, pressure in
the systemic arteries averages about 80
mmHg.
• In Isometric contraction period,
intraventricular pressure sharply rises as
ventricle contracts in a closed cavity due to
closure of both AV & Semilunar valve.
• In maximum ejection phase, pressure in the lt
ventricle and aorta rises about 120 mmHg,
when blood passage out & volume decreases
• But the force of contraction is stronger than
out flow, so intraventricular pressure rises .
17. Pressure change in ventriular diastole:
• In protodiastolic phase, pressure continue
to fall.
• In isomertic relaxation phase, LV pressure
sharply falls blow the pressure in Aorta,
semilunar valves snap shut. The pressure
in the aorta falls to 80 mmHg, while
pressure in the left ventricle falls to 0
mmHg.
• Rapid filling phase: When the pressure in
the ventricles falls below the pressure in
the atria, the AV valves open and a phase
of rapid filling of the ventricles occurs.
• last rapid filling phase, corresponds with
atrial systole, blood pumps into ventricle
& pressure suddenly rises.
Pressure change in Ventricle:
18. Pressure changes during cardiac cycle
Pressures observed within cardiac chambers during systole and
diastole
Heart region Pressure (mmHg)
Right atrium 0-4
Right ventricle 25 systolic; 4 diastolic
Pulmonary artery 25 systolic; 10 diastolic
Left atrium 8-10
Left ventricle 120 systolic; 10 diastolic
Aorta 120 systolic; 80 diastolic
19. • During diastole, normal filling of the ventricles increases the volume of
each ventricle to about 110 to 120 milliliters. This volume is called the
end-diastolic volume.
• Then, as the ventricles empty during systole, the volume decreases
about 70 milliliters, which is called the stroke volume.
SV=EDV−ESV
• The remaining volume in each ventricle, about 40 to 50 milliliters, is
called the end-systolic volume.
• The fraction of the end-diastolic volume that is ejected is called the
ejection fraction - usually equal to about 60 per cent.
ejection fraction (EF) is used to evaluate stroke volume and
contractility. It is described as:
EF=(SV / EDV)×100%
A higher EF suggests more efficient heart activity.
Volume changes in ventricles:
20. Phonocardiogram
A graphic recording of cardiac
sound
A specially designed
microphone on the chest wall.
Sound waves amplified,
filtered and recorded.
Doppler Echocardiography has
replaced the
phonocardiography
21. 1st heart sound(lubb)
•The 1st heart sound, marks the
beginning of systole (end of diastole).
•Related to the closure of the mitral
and tricuspid valves.
2nd heart sound (Dub)
• The 2nd heart sound, marks the
end of systole (beginning of
diastole).
• Related to the closure of the aortic
and pulmonic valves
Heart sound in cardiac cycle
22. Heart sound in cardiac cycle
Third Heart Sound
• The third heart sound (S3) is a low-
pitched, early diastolic sound
audible during the rapid entry of
blood from the atrium to the
ventricleFourth Heart Sound
The fourth heart sound (S4)
• is a late diastolic sound that
corresponds to late ventricular
filling through active atrial
contraction. It is a low-intensity
sound heard best with the bell of
the stethoscope.