# Heart
The heart is a four-chamber muscle central pumping organ that receives and pumps blood throughout the body. It is a conical or heart-shaped organ, originally 12 centimeters (5 in) wide, 8 centimeters (3.5 in) wide and 6 centimeters (2.5 in) in thickness.
# Location:
It is located in the medial mediastinum between the two lungs and is placed obliquely behind the body of the sternum. About a third of it is on the right and two-thirds of it on the left of the middle.
# Heart Level:
Three layers of tissue from the wall of the heart.
1. Epicardium: The outer layer of the wall of the heart
2. Myocardium: The middle layer of the heart
Endocardium: The inner layer of the heart.
# Chamber of Hearts:
The inner cavity of the heart is divided into four cells:
1. Right atrium
2. Right ventricle
3. The left atrium
4. Left ventricle
The two atria are thin-walled chambers that receive blood from the veins. The ventricles are densely walled cells that forcefully pump blood from the heart. This difference in thickness is due to the presence of myocardium in the chamber. The right atrium receives deoxygenated blood from the systemic vein and the left atrium receives oxygenated blood from the pulmonary vein.
# Heart valve:
There are four valves in the heart.
1. Right atrioventricular valve a . It is located between the right atrium and the right ventricle b . It is also called a tricuspid valve.
C. It has three casks
Me. Anterior or infanadibular
Aa Successive or marginal iii. Medial or septal
2. Left atrioventricular valve a . It is located between the left atrium and the left ventricles . This is called bispecid valve or mitral valve CO . It has two cusps
Me. Anterior or cosmic ii .posterior
3. Semilunar valve a . They are located at the base of the large vessels leaving the ventricles . They are of two types: pulmonary and aortic.
C. The pulmonary semilunar valve is located between the right ventricle and the pulmonary trunk.
D. The aortic semilunar valve is located between the left ventricle and the aorta.
# Heart muscle
It is also called cardiac muscle, formed by involuntary striated muscle, known as myocardium. The heart muscles are made up of three major types of cardiac muscles
1. The muscles of the atria
2. Ventricular muscle
3. Special stimulating and conductive muscle fibers-
A. The SOS node (SA node)
B The second letter of the English alphabet. Intranodal tract c . Atrioventricular node (AV node)
D. AV bundle e . Purkin fibers
# Functional structure of the heart muscle:
A. Myocardial cells or myocytes are functional units of the myocardium.
B The second letter of the English alphabet. They are about 100µm long in branching system.
C. They contain a bundle of parallel myofibrils.
D. Each myofibril is composed of a similar serum.
E. A sarcomere is bound to two transverse Z lines.
F. Actin filaments attach to the Z line and overlap with the dense parallel protein filaments known as myosin.
G. Actin and myosin bind to each other cross-bridges that contain ATPase.
J. Sarcomare is the unit of contraction of the myocardium.
Me. The cells of the muscle fibers are widely branched and are connected to each other via intercalated disks.
J. The intercalated discs are part of the sarcolemma (a membrane of a striated muscle fiber cell) and have two structures: gap junctions and desmosomes.
T A gap junction forms the channel between adjacent cardiac muscle fibers that allows currents to flow from one cardiac muscle cell to another.
Yes. Lysosomes are a cell structure that anchors the edges of cardiac muscle fibers together so that cells do not differentiate during compression of individual fibers.
Mr. The myocardium is divided into two populations:
1. pacemaker and management cell i ) SA node ii). AV junctional tissue iii) His iv) Bundle of Purkinje fiber
2) Myocardial cell functioning
i) Actin ii) Myosin iii) Troponin iv) Tropomyosin
# The connective tissue of the heart
Cardiac muscle is typically composed of certain structures that are responsible for initiating and conducting cardiac impulses at a regular and faster rate than other muscles. These are called connective tissue of the heart.
1. Sinus node (China-atrial node or SA node)
2. The path of the internodal atrial
3. atrioventricular node (AV node)
৪. His and the bundle of branches
5. Purkin Fiber
It is one of the major components of the cardiac conduction system that regulates heart rate.
। It is a banana-shaped structure that varies in size, usually 10-30 mm long, 5-7 mm wide and 1-2 mm deep.
য়ে In a healthy heart, the SA node continuously creates an activity, establishes the rhythm of the heart and is therefore known as the natural pacemaker of the heart.
। It consists of a cluster of cells located at the upper vena cava connector at the upper part of the right atrioventricular wall. These notches run between the entrances of the superior vena cava and the inferior vena cava.
। It produces electrical tendons and conducts them throughout the heart muscle, encouraging the heart to contract and pump blood.
These cells maintain about 70-80impulse per minute, which imparts up to natural heart rate.
2. Internal concealment path
। This is the path that guides the emotions from the SA node to the AV node and the left atrium.
এই These internodal tracts contain purkinje fiber.
Three three-way there is i . Bacamyanera a previous intaranodala tract [George byacamyana]
Aa Intermodal tract between Wenzbach (Karel Frederickwenbach)
III. A posterior internodal tract of the thorax
The anterior internodal tract, after exiting the SA node, is curved around the superior vena cava and divided into two. The dwarf bundle, induces the left atrium and merges into another AV node.
মাঝ The medial internodal tract is merged from the SA node to the AV node.
postiriora intaranodala tract to reach the AV node.
। Collectively, they serve as peripheral pathways for the transmission of emotion from the SA node to the AV node and the left atrium.
3. The AV node
It is located at the north and right borders of the interstitial septum (wall of tissue that separates right and left atria of heart).
The atrioventricular node or AV node is a part of the cardiovascular system that combines the apex of the heart.
। It usually manages the motivation between the atria and the ventricle.
S Cells are mainly cardiac muscle fibers with low myofibril.
They transmit impulses from the node to the SA node through him and his branch bundle at a rate of 0.1 m / s.
AV nodal impulse at a rate of 40-60 impulse / min.
ক্ষেত্রে In case of SA node failure, AV node can generate impulse and that is why it is called Reserve pacemaker.
৪. His or the AV bundle bundle: [Wilhelm his junior]
। It extends from the AV node and extends across the medial septum.
The intarabhentrikulara septamera the top, it is divided into left and right branches.
The left bundle is further divided into anterior and anterior aorta.
All physical Purkinje system and branches are combined.
It is the system that propagates from the atrium to the ventricle.
In the case of SA or AV node failure, he can generate the impulse at a rate of 30-36 impulse/min in bulk.
5. Perkin Fiber
Purkinje fibers are specialized conducting fibers with a low number of myofibrils and mitochondria.
They can handle cardiac action potentials more quickly and efficiently than any other cell in the heart.
। It originates from the branch of his bundle, from the intestinal septum to the papillary muscles of the heart.
fiber bhentrikulara mayokardiyamera spread to all parts.
It imapalasa 15-40 / minute rate could start prompting.
# Characteristics of heart muscles
The characteristics of the heart muscle are:
1. Autonomy
2. Tension and contraction
A. All or any law b . Frank-Sterling Law
3. Driver
4. Refractory duration
5. Tonicity
A. Auto-correction
1. No external stimulation of the muscles of the heart is required to produce emotion (automata) at regular intervals.
2. The heart muscles are induced by their junctional tissue at regular intervals with no external stimulation.
৩. The SA node and the junctional tissues produce induced rather than myocardial cells.
৪. The SA node produces impulses and propagates other junctional tissues throughout their myocardial cells.
B Excitation and contraction
1. Response of the muscles of the heart to a stimulus of sufficient strength and duration.
2. Minimum chance of excitement is -1 meter.
৩. The stimulation and response can be either electrical, mechanical or thermal.
৪. Heart muscle stimulation shows when a stimulus is involved and it develops the possibility of an action.
৫. This propagated action is likely responsible for initiating contraction.
6. This contraction is due to chemical and mechanical changes between Actin and myosin.
All . All the contractions put pressure on the blood in the ventricle to come out of these cavities, and the blood pressed on.
A. All or no law
If stimulation is applied sufficiently to the muscles of the heart, then the muscles respond most to it, but if the stimulus is not sufficient, it will not respond at all.
B The second letter of the English alphabet. Frank Sterling Law
In physiological limits, the longer the length of cardiac muscle fibers, the greater the compressive strength.
The C driver
1. It is the ability to transmit the tendency generated from the SA node to the rest of the heart muscle.
2. The source, generated from the SA node at a rate of 70-80 Imps / min, goes to the junction fibers of the AV node with an accelerated internodal path of 0.04 seconds.
৩. From the junction fibers, the tendon reaches the AV nodal fiber at a speed of 0.06 seconds.
The stimulus then travels to the transitional fibers with 0.1-second delay before excitation.
D. Refractory duration
1. It is a period in which the heart muscle is unresponsive to external stimulation.
2. The refractory period of the heart is 0.30 seconds.
৩. It is of two types: absolute and relative.
৪. In absolute RFP, the muscles of the heart are resistant to any stimulation, and it takes about 0.25 seconds.
৫. In relative RFP, the cardiac muscle is slightly responsive to any strong stimulus and is almost
0.05 seconds
This tonic
It is a partial contraction of the heart muscle over the underlying blood.
* Pacemaker (SA node)
In a general sense, the pacemaker is the rider who sets the pace of a nation. The SA node is called a heart pacemaker because it produces 70-80 impulses / minute. The emotions are first generated at the SA node and they maintain the entire cardiac rhythm. The rate and rhythm are higher than any other junctional tissue in the heart, such as the SA node called the pacemaker of the heart.
# Cardiac cycle
The cardiac cycle is the cardiac events that occur from one heartbeat to the next. The cardiac cycle is inversely proportional to the heart rate. If the normal heart rate is 75, the cardiac cycle will be 60/75 seconds or 0.8 seconds.
# Events in the cardiac cycle
In atria
1. Atrial systole
Systole is the period of contraction of the muscles of the heart. The atrial systole initiates the cardiac cycle as the stomachmaker (SA node) is in Atheria. Duration is about 0.1 seconds. It drives some blood (30%) into the ventricle.
2. Atrial cardiovascular atrophy
Diastole is the period of muscle relaxation. At the end of the atrial systole, there is atrial diastole. During this period, blood enters the atria from the great vein. Duration is about 0.7 seconds. About 70% of ventricular filling occurs during this period.
In the ventricle
3. Ventricular systole
It starts at the end of the atrial systole and lasts 1.5 seconds. At the beginning of the episode, the valve of AV and Semiluna closes and produces the sound of the 1st heart. The pressure appears up to 120 mm-Hg and the semilunar valves are open. As a result, blood is released from the ventricle.
4. Ventricular diastole
It starts at the end of the ventricular systole and lasts 0.5 seconds. It starts with the semilunar valve closing. As diastole begins, the ventricle pressure drops to 80 mm-Hg and produces a second heartbeat.
#Transmission of the heart:
The human circulatory system has a two-part system (systemic and pulmonary) whose purpose is to bring oxygen-carrying blood to all tissues of the body. In a systematic loop, blood circulates in the body's system, brings in oxygen, and collects carbon dioxide waste. In the lung loop, blood is circulated to and from the lungs to emit blood carbon dioxide and to pick up new oxygen.
Pulmonary loop (controlled by the right side of heart)
1. Oxygen-poor blood from the right atrium (10) reaches the right ventricle (1) via the tricuspid valve.
2. During ventricular contraction, the blood pushes into the pulmonary artery (2), which is divided into two main parts: one to the left lung (3) and the other to the right lung (3).
৩. Here, the blood rich in carbon dioxide in the lungs is converted to oxygen-rich blood.
৪. The fresh, oxygen-rich blood returns to the left atrium (5) of the heart via the pulmonary vein (।).
Systemic loop (controlled by the left side of the heart)
1. Oxygen-rich blood (3) from the lungs enters the left atrium (5) of the heart through a pulmonary vein (4).
2. As the chamber is full it presses the mitral valve and blood flow to the bottom left ventricle (6).
৩. During ventricular contraction, the blood on the left side is pressed into the aorta ()).
৪. The pandemic releases oxygen to all the cells of the body through a network of blood vessels and capillaries (৮).
৫. Blood used from the body is returned to the heart through the veins.
The . All blood from the body is ultimately collected in the two largest veins: the upper vena cava (9), which receives blood from the upper body, and the inferior vena cava, which receives blood from the lower body region.
Both . In both veins, blood reaches at the right atrium of the heart (10).
Renal circulation:
The renal circulation supplies blood to the kidneys through the arteries in the kidney, left and right, which branch directly from the aorta of the lower abdomen. The kidneys account for about 20% of cardiac output despite their relatively small size.
Cerebral Circulation: Blood circulation through the network of cerebral arteries and veins that provide cerebral circulation to the brain.
# The word of the heart
The pulsing motion of the heart was produced during various events of the cardiac cycle through the heart and produced a special acoustic sound called the heart sound. Heart's words are four in number. The sounds of the 1st and 2nd heart are audible through the stethoscope but have been detected by the third and fourth phonoderographs.
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Clinical significance:
1. Diagnosis of valvular heart disease
2. Diagnosis of cardio-dynamic status
৩. Diagnosis of congenital heart disease
3 ) The jaw is different or whether it is systolic or diastolic.
# Pulse
The pulse is the rhythmic propagation and expansion of the supernatural wall as a result of pressure changes caused by the excretion of blood from the heart to the periphery. The normal range of pulses is 6090 / min.
# The result of heart disease
The amount of blood that comes out of each ventricle or pumps into the aorta every minute through the heart is called cardiac output.
Cardiac output CO = stroke volume * heart rate = 70 * 72 ml = 5042 ml / min = 5.04 liters / minute.
The stroke rate is 70 ml/beat and the heart rate is 72 beats/min (average).
# Stroke volume
The amount of blood that is extracted by each ventricle on each beat is the amount of stroke. It is about 70 ml. Stroke volume = end-diastolic volume - end-systolic volume.
# Factors affecting cardiac output
1. Physiological
a. Age: CO increases with age
b . Gender: Due to low body weight and surface area, women have 10-20% less CO than men.
C. Surface area: The greater the surface area, the more CO.
D. Posture: CO sits and lies more than erect posture.
E. Practice: CO increases significantly in severe exercise.
F. The emotion, the temperature.
2. Pathological
a . Hyperthyroidism: CO increases due to high body metabolism.
B The second letter of the English alphabet. Fever: CO increases as temperature and metabolism increase.
C. Anemia, fibrillation, noise
# Factors controlling cardiac output:
1. Venus returns 2. Heart contraction force 3. Frequency of heart rate 4. Ejection fraction
5. Peripheral resistance
# Cardiac index
The cardiac output is the cardiac index per square meter of body surface area.
The average value is 3.5 liters / minute / sqm
# Last systolic volume
The volume of blood that is in each ventricle at the end of the ventricular systole. It is about 40-50 ml.
# Last Diastolic Volume
The volume of blood that is in each ventricle at the end of the ventricular diastole. It is about 110-120 ml.
# Back to the vein
It is the amount of blood that comes from the periphery every minute to the right atria of the heart. This equates to cardiac output. It is about 5 liters/minute.
# Total peripheral resistance
Blood must be overcome when the periphery is passed. This is expressed as TPR = p / q, where p is the pressure and q is the blood flow.
Blood Pressure: It applies blood to the blood vessels or walls of the heart cells.
Comparison curves
Diastolic vs. systolic comparison chart
Diastolic systolic
The definition is that the pressure is placed on the walls of the various arteries around the body when the heart relaxes. It measures the amount of blood pressure applied to the arteries and vessels while striking the heart.
Normal range 60 - 80 mmHg (adult obtained); 65 mmHg (infant); 65 mmHg (6 to 9 years) 90 - 120 mmHg (adult); 95 mmHg (infant); 100 mmHg (6 to 9 years)
The importance of elderly diastolic readings is especially important in monitoring blood pressure in young people. As a person ages, the importance of measuring their systolic blood pressure increases.
Blood pressure represents the lowest pressure in the diastolic artery. Represents the maximum pressure applied to the systolic artery
Blood Vessels Relaxed Contract
The lower the number of blood pressure reads is the diastolic pressure. The higher the number is the systolic pressure.
# Heart shaking
Heart rate is the heart rate per minute. The average range is 60-90 / min for an adult with an average of 72 beats/min.
# Factors Affecting Heart Rate
1. Respiration: HRT increases during inspiration and decreases with expiration.
2. Cardio-Vascular Reflexes: Reduction of Baroreceptor and Stimulation of the Brain Bridge Increases HR.
3. Temperature: Increasing temperature increases HR by stimulating the SA node.
৪. Intracranial pressure: Increased intracranial pressure slows down HR.
৫. Muscular Exercise: It increases HR by reducing O2 and increasing body temperature.
6. Age: From infancy to old age, gradually decreases.
Ender. Gender: Women have slightly faster HR than men.
8. Surface area: HR in inversely proportional to the surface area of the surface.
# Tachycardia
The term tachycardia means fast heart rate. An increase of HR above 100 beats/min is commonly referred to as tachycardia.
# Bradycardia
The term bradycardia means a slower rate of growth. The reduction of HR below 60 beats/min is commonly referred to as bradycardia.
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Autonomic nervous system: The part of the nervous system that regulates the involuntary activity of the heart, intestines, and glands.
Sympathetic nervous system: A part of the autonomic nervous system that increases blood pressure and heart rate under pressure, restricts blood vessels and dilates students.
Parasympathetic nervous system: part of the autonomic nervous system that inhibits or opposes the effects of the sympathetic nervous system.
Norepinephrine: A catecholamine with multiple roles including hormones and neurotransmitters. Areas in the body that are produced or damaged by these substances are described as noradrenergic.
Cardiovascular Center: The Cardiovascular Center is an organ of the autonomic nervous system and responsible for controlling cardiac output.
Located in the Medulla Icongata at the Cardiovascular Center, the Cardiovascular Center has three distinct components: the Cardio Accelerator Center, the Cardioinhibitory Center and the Vasomotor Center. These are a cluster of neurons that work independently to control blood pressure and flow.
The majority of these neurons act by releasing neurotransmitter norepinephrine (adrenaline) from sympathetic neurons. Although each center operates individually, they are not physically separate.
The Cardiac Accelerator Center stimulates cardiac function by controlling heart rate and stroke volume through sympathetic stimulation from the nerve.
Cardiovascular center slows cardiac function through parasympathetic stimulation from the visceral nerve, reducing heart rate and stroke volume.
The vasomotor center controls the tone or smooth muscle contraction of the vessel in the tunica media. Changes in diameter affect peripheral resistance, pressure, and flow, which in turn affect cardiac output.
Baroreceptors: A nerve endings that are sensitive to blood pressure changes. Baroreceptors are specialized stretch receptors within the thin areas of the blood vessels and small areas of the heart that respond to the degree of stretch caused by the presence of blood.
• They send literature to the blood pressure control cardiovascular center. Vascular baroreceptors are mainly found in the sinuses (small cavities) in the aorta and carotid artery.
• The aortic sinus, only the aortic valve, is found in the superior ascending cervical wall as the carotid sinus is located in the base of the internal carotid artery.
• Also, the inferior baroreceptors are located in the vena cava and on the right atrium wall.
• When blood pressure rises, baroreceptors expand more tightly and at a higher rate when the possibility of action begins.
• Low blood pressure extends to low degrees and slows firing rate. When the cardiovascular center of the medulla oblongata receives this input, it is a reflex that trips which maintains homeostasis.
Blood Pressure Control:
1।
2।
1A. Baroreceptor Reflexes:
When blood pressure rises too high, baroreceptors shoot at high rates and trigger parasympathetic stimulation of the heart. As a result, cardiac output falls. Sympathetic stimulation of peripheral arterioles will also decrease, resulting in vasodilation. Combined, these activities cause blood pressure to drop.
When blood pressure is too low, the rate of firing of the baroreceptor decreases. This triggers an increase in sympathetic stimulation of the heart, thereby increasing the cardiac output. It also drives the sympathetic stimulation of peripheral vessels, resulting in vasoconstriction. Combined, these activities increase blood pressure.
1B chemoreceptor mechanism:
1C. Ischemic response to the central nervous system:
2. Long-term control:
• Juxtaglomerular cell: The juxtaglomerular cell (JG cell or granular cell) is the cell in the kidney that synthesizes, stores, and secretes the enzyme renin.
• Adrenal Cortex: The outer part of the adrenal gland that produces the hormones required for homeostasis.
• Aldosterone: A mineralocorticoid hormone secreted by the adrenal cortex that regulates the body's sodium and potassium balance.
# Depolarisation and repolarization of cardiac muscles
• Cardiac cells at rest are considered polarization, which means no electrical activity takes place.
• The myocardial cell when resting has a negative membrane potential.
• Electrical impulses are created by the automaticity of specialized cardiac cells.
• Once the electric cell produces an electrical tendency, these electrical propulsion ions cross the cell membrane, called activity potentials.
• Stimulation above a threshold value gives voltage-limiting ion channel opening and a flood of cations to the cell.
• An action of the ion by entering the positively charged cell can be characterized by potential depolarization.
• The movement of ions across the cell membrane through sodium, potassium and calcium channels, causing contraction of cardiac cells/muscle (shrinkage).
• Depolarization with the corresponding contraction of a wave-like myocardial muscle moves through the heart.
• Repolarization returns the ions to their previous resting state, which is not identical to the relaxation of the myocardial muscle (dilation of the cardiac atrium).
• After a delay, the potassium channel opens, and K + causes repolarization to occur while sleeping out of the flow cell.
• Depolarization and repolarization of electrical activities have caused muscular activity.
• Repolarization cycle - The potential curve of activation shows electrical changes in the myocardial cell during depolarization.
• This electrical activity is done when the ECG, or muscular activity is detected.
# Action potential
The possibility of cardiac action is a brief change in the voltage (membrane potential) across the membrane of the cardiac cell. This is caused by the movement of ions inside and outside the cell through the ion channels.
NB: The leakage of these ions, across the membrane, is maintained by the activity of the pumps, which help to keep the intercellular density more or less constant.
1. Sodium (from Na +) and potassium (k +) ions are governed by the use of energy in the form of sodium-potassium pumps that move out of the cell and into two K + cells (in the form of adenosine triphosphate (ATP)).
2. Sodium-calcium exchanger that removes a Ca2 + from the cell for three Na +.
Episode # of action possibilities
The resting membrane potential of myocardial cells is about -90 millivolts. It is more negative than the outside inside the membrane. The major ions found outside the cell at rest are sodium (Na +) and chloride (Cl), but inside the cell it is mainly potassium (K +).
Stage 0: Degradation
১. As a result of activity in neighboring cardiomyocytes, the membrane potential can rise above 1 mV.
2. Starting to open the Na + channel one by one and leak information into the Na + cells, raising further membrane potential.
৩. The membrane potential approaches of m70mV, at this point, open sufficiently fast Na + channels to generate self-sustaining internal Na + current.
৪. The large N + current rapidly divides the MP into 1 mV.
৫. No + channels are time dependent, no + channels are off.
6. L-type ("long-opening") Ca2 + channels are -40 mV larger than TMP when open.
First Stage: Early Recovery
1. This episode begins with the rapid inactivation of Na + channels.
2. At the same time the potassium channels open and close very quickly, allowing a short flow of potassium ions from the cell, making the membrane potential a bit more negative.
Stage 2: The Plateau Episode
1. Ca2 + channels are still open and Ca2 + has a small, constant internal current.
2. K + traps its density gradient through channels.
৩. These two defenses are electrically balanced and the membrane potential remains in a plateau below 0 mV throughout the phase.
The third step: redistribution
1. Ca2 + channels are slowly inactivated.
2. The continuous external trend of K + returns to the possibility of resting - 90 mV - to prepare the room for a new cycle.
# ECG (electronic card)
It records the electronic changes of the heart from the body surface of each cardiac cycle.
# A pretty common ECG
A typical ECG drawn five-wave PQRST shows shows three positive waves, P, R, T and two negative waves, Q, S and a complex QRS.
1. P wave:
A. This is the first ward upward reflection with a small constant wave.
B The second letter of the English alphabet. It represents activation of left and right atrial activity (atrial depolarization).
C. This induction originates at the SA node with a 0.10-second duration and 25 mV voltage.
D. This indicates that the SA node works correctly.
2. Question wave:
A. This is a downward, small isolation.
B The second letter of the English alphabet. This represents septal depolarizing from left to right, created by septal activity.
C. It usually presents with left ventricular function.
D. Cue waves greater than 1 small square in width and deeper than 2 mm indicate myocardial infarction.
3. R wave:
A. This is an upward-reflection with the hit constant and the longest peak of the obvious.
B The second letter of the English alphabet. It follows along with the Q Wave.
C. This indicates apical left ventricular degeneration.
৪. S Wave:
A. This is a downward reflection of the R wave.
B The second letter of the English alphabet. It represents posterior basal left ventricular depolariization.
5. QRS Critical:
A. The QRS complex represents the activation of the right and left ventricles.
B The second letter of the English alphabet. It is produced by ventricular depolarization and atrial repolarization.
C. The total duration is 0.08-0.10 seconds.
D. Because of the large ventricular mass, the peak is larger than the P wave.
6. T wave:
A. It is a slow and low wave produced by ventricular reabsorption.
B The second letter of the English alphabet. It has a 0.2-0.4 mV voltage with a duration of 0.13 seconds.
C. Reversal of the t wave in ischemia, heart block or digoxin poisoning.
7. ECG intervals:
AP-R intervals
Me. This is the length of time from the beginning of the P wave to the start of the QRS complex.
Aa Duration is 0.12-0.20 seconds.
III. The 0.4-second pause indicates that the heart block can occur at any time.
b.QT intervals i . It extends from the beginning of the QRS complex to the end of the T wave.
Aa Duration <0.44 seconds.
III. The length of the QT interval indicates the event of sudden death.
CR-R intervals
Me. It is two consecutive and wave intervals.
Aa The same RR intervals indicate degeneration of the rhythmic ventricle.
III. Duration is 0.80-0.83 seconds.
DP-P intervals
Me. It is the interval between two successive P waves.
Aa The same PP intervals indicate the rhythmic atrial degradation.
ES-T Departments i . This is the period between the end of the QRS and the start of the T wave.
Aa This section should be isoelectric and straight line.
FT-P intervals
Lymphatic System:
The lymphatic system is a part of the circulatory system and an important part of the immune system, in combination with a large network of lymphatic vessels that direct the fluid from the vascular to the heart. The lymphatic system was first described independently in the seventeenth century by Olaus Rudebeck and Thomas Bartholin.
The lymphatic and blood circulatory system are very closely involved but they work quite differently. The blood system is two-dimensional (blood flows in two directions, away from the heart and away) in a closed circulatory system (blood flows through it but cannot get out of it). It is controlled by the central organ, the heart, which beats the blood and pumps blood through the circulation system.
The lymphatic system is a one-way circulatory system (the lymph always travels in one direction, towards the heart). It lacks the central pumping system like the heartbeat; Instead, the compression of the lymph vessels causes the lymph to be pushed through the system.
Human blood circulation processes an average of 20 liters of blood daily through capillary filtration, which removes plasma when it is released. About 17 liters of filtered plasma is directly resuspended in the blood vessel, while the remaining 3 liters are in the interstitial fluid. One of the main functions of the lymph system is to provide an accessory return route for three liters of blood for the surplus.
The components of the lymphatic system:
- Lymph
- Lymphatic vessels
- Lymph node:
- Lymphatic tissues and lymphatic organs
১. Lymph: (Latin, nymph means "water") A is a clear, sometimes strangely yellow and somewhat gradual, fluid that is collected from all the body in tissues, flows through the lymphatic vessels and lymph nodes, and finally. Blood is added to the veins.
Lymph Composition:
Lymph contains a variety of substances, including protein, salt, glucose, fat, water and white blood cells. Unlike your blood, the lymph usually does not contain any red blood cells.
The composition of the lymph changes drastically depending on where it originates in your body. On the lymphatic vessels in your arms and legs, the lymph is clean and transparent and its chemical combination is like blood plasma (the fluid part of the blood). However, lymphoma contains less protein than plasma.
The lymph that returns from your intestines is due to the fatty acids in your diet. This mixture of fat and lymph is called chile, and the specialized lymphatic vessels around your intestine that collect chile are called lactails.
2. Lymph capillaries: Lymphatic circulation starts at the blind end (closed at one end) through highly permeable superficial lymph capillaries, which contain button-like junctions through endothelial cells that allow fluid to pass through them when the interstitial pressure is high enough. .
৩. The lymphatic vessels are similar and attached to the blood vessels. However, the lymphatic vessels transport the lymph during the blood transfusion, which eventually enters the bloodstream while the blood vessels are always in the bloodstream.
i) Afferent ships
Afferent lymph vessels enter all parts of the periphery of the lymph node and open into the lymph sinus of the cortical part after branching and thickened plexus formation in the capsule material. It carries the lymph located at the node. Doing so they lose all the coats except their endothelial lining which is continuous with a layer of cells similar to the lining in the lymph pathways.
Afferent lymphatic vessels are found only in the lymph nodes. This is in contrast to the pleural lymphatic vessels that are also found in the thymus and plane.
ii) Shipwrecked ships
The pulmonary lymphatic vessel begins at the lymph sinus of the medial part of the lymph node and leaves the lymph nodes in the hilum, either in the veins or in the larger nodes. It carries filtered lymph beyond the node.
Afferent lymphatic vessels are also found in the thymus and plane. This is in contrast to afferent lymphatic vessels that are found only at the lymph node.
• 4. The lymphatic duct is a great lymphatic vessel that empties the lymph into a subclavian vein. There are two lymph vessels in the body - the right lymphatic tube and the bust tube. The right lymphatic duct protrudes from the right upper limb, the left upper limb, and the right side of the head and neck. Thoracic duct in the left brachiocephalic vein between the buccal subclavian and left internal jugular veins drains the thoracic duct into the blood circulation system.
• 5. Lymph nodes: small ovarian bodies of the lymphatic system, armpit, nipple, neck, chest cluster, and abdomen.Only the organ that distributes along the filter lymph; A site for T and B cell activation.
- Oval structures located along the lymphatic
- Involved by a fibrous capsule
- Cortex = outer part
Germinal centers produce lymphocytes
- Medulla = inner part
• The marrow rope
- Lymph afferents enter the nodes via lymphatics, flow through the sinuses, exit through the lung lymphatics.
Ly. Lymphoid tissues and organs are found at various sites in the body and are heavily populated by lymphocytes (white blood cells that protect against infection and are part of the immune system).
A. The tonsils
1. Pharyngeal tonsils (adenoid)
- A single tonsil on the walls of the mouth
2. Palatine tonsils
- A pair; In the northern part of the Oral Cavity
- The largest and most frequently infected is called tonsillitis (treatment - with tonsillectomy or antibiotic).
৩. Lingual tonsils (many)
- At the root of the tongue
Function: The main function of the tonsils is to trap germs (bacteria and viruses) that you can breathe the Antibodies produced by the immune cells of the tonsils help to kill germs and help prevent throat and lung infections.
B The second letter of the English alphabet.
The largest lymphatic organ
Located between the abdomen and the diaphragm
The structure is like a node
• Capsules present
• However, there are no approved vessels or sinuses
Place of call
• Red decoration contains all the ingredients
Blood circulation
White pulp is similar to lymphatic nodules
Activities
Filters blood, saves blood
C. Thymus gland
- Position - behind the sternum of the mediastinum
- The capsule divides it into 2 lobes
- Development
• Children - obvious
• Adolescence - Maximum size
• Maturity - decreases in size
- Function
• Differences and completeness of T cells
Function of the lymphatic system
1. Liquid recovery:
ECF from TC absorbs proteins and fluids (2 to 4 L / day) and returns it to the bloodstream.
• Interference with lymphatic drainage leads to acute inflammation such as. Lap
• Cause-mosquito-carrying roundworms will infect lymph nodes and block the lymph flow
• Symptoms - chronic inflammation, especially aggravation; Thickening of the skin
2. Immunity:
• Fluids are filtered from all capillary beds
• Resistant cells are ready to react with foreign cells or chemicals
3. Lipid absorption:
• Lacteals in the small intestine can absorb dietary lipids.
The end
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