Post on 03-Jan-2016
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Cardiovascular SystemCardiovascular System
HeartHeart
Introduction of Cardiovascular Introduction of Cardiovascular SytemSytem
Consists of;Consists of;
1.1. BloodBlood
2.2. HeartHeart
3.3. Blood VesselsBlood Vessels
Location of HeartLocation of Heart
Heart lies between the lungs in the Heart lies between the lungs in the mediastinum.mediastinum.
Location of HeartLocation of Heart
Two-thirds of its mass is to the left of Two-thirds of its mass is to the left of the midlinethe midline
Location of HeartLocation of Heart
Precordium – The area of the chest Precordium – The area of the chest anterior to the heart anterior to the heart
Location of HeartLocation of Heart
Lies between the vertebral column Lies between the vertebral column and the sternumand the sternum
Structure and Function of Structure and Function of HeartHeart
1.1. PericardiumPericardium
2.2. Layers of the Heart Wall Layers of the Heart Wall
PericardiumPericardium
The heart is enclosed and held in The heart is enclosed and held in place by the pericardiumplace by the pericardium
PericardiumPericardium
Consists of;Consists of;
1.1. Fibrous pericardium (outer)Fibrous pericardium (outer)
2.2. Serous pericardium (inner) Serous pericardium (inner)
PericardiumPericardium
Fibrous pericardium – anchors the Fibrous pericardium – anchors the heart in the mediastinumheart in the mediastinum
PericardiumPericardium
Serous pericardium composed of;Serous pericardium composed of;
1.1. Parietal layerParietal layer
2.2. Visceral layerVisceral layer
PericardiumPericardium
Pericardial cavity – a space between Pericardial cavity – a space between the parietal and visceral layers filled the parietal and visceral layers filled with pericardial fluid with pericardial fluid
Layer of the HeartLayer of the Heart
1.1. EpicardiumEpicardium
2.2. MyocardiumMyocardium
3.3. EndocardiumEndocardium
EpicardiumEpicardium
Consists of the visceral layer of Consists of the visceral layer of pericardium and connective tissue pericardium and connective tissue (adipose)(adipose)
MyocardiumMyocardium
Composed of cardiac muscleComposed of cardiac muscle
MyocardiumMyocardium
The cells are branched, involuntary, The cells are branched, involuntary, and have one nucleusand have one nucleus
MyocardiumMyocardium
The cells are connected by The cells are connected by intercalated discs, which have gap intercalated discs, which have gap junctions that allow ions to flow in junctions that allow ions to flow in between cells during depolarizationbetween cells during depolarization
EndocardiumEndocardium
Lines the chambers and covers the Lines the chambers and covers the connective tissue in the heart valvesconnective tissue in the heart valves
EndocardiumEndocardium
It consists of endotheliumIt consists of endothelium
Chambers of the HeartChambers of the Heart
1.1. Right AtriumRight Atrium
2.2. Right VentricleRight Ventricle
3.3. Left AtriumLeft Atrium
4.4. Left VentricleLeft Ventricle
Chambers of the HeartChambers of the Heart
On the surface of the heart are On the surface of the heart are auricles and sulciauricles and sulci
Chambers of the HeartChambers of the Heart
Auricles – small pouches on the Auricles – small pouches on the anterior surface of each atrium anterior surface of each atrium
Chambers of the HeartChambers of the Heart
Sulci – Are grooves that contain Sulci – Are grooves that contain coronary arteries and fat and coronary arteries and fat and separate the chambersseparate the chambers
Right AtriumRight Atrium
The right atrium receives systemic The right atrium receives systemic venous blood from;venous blood from;
1.1. Superior Vena CavaSuperior Vena Cava
2.2. Inferior Vena CavaInferior Vena Cava
3.3. Coronary sinusCoronary sinus
Right AtriumRight Atrium
The atrium receives blood low in O2 The atrium receives blood low in O2 and high in CO2and high in CO2
Right AtriumRight Atrium
Interatrial septum - separates the Interatrial septum - separates the right and left atriaright and left atria
Right AtriumRight Atrium
Fossa ovalis – an oval depression in Fossa ovalis – an oval depression in the interatrial septum; it is a remnant the interatrial septum; it is a remnant of the foramen ovaleof the foramen ovale
Right AtriumRight Atrium
Tricuspid Valve – Blood passes from Tricuspid Valve – Blood passes from the right atrium into the right the right atrium into the right ventricle through hereventricle through here
Right VentricleRight Ventricle
Forms most of the anterior surface of Forms most of the anterior surface of the heartthe heart
Right VentricleRight Ventricle
Pulmonary semilunar valve - Blood Pulmonary semilunar valve - Blood passes from the right ventricle to the passes from the right ventricle to the pulmonary trunk via this valvepulmonary trunk via this valve
Left AtriumLeft Atrium
Receives pulmonary venous blood Receives pulmonary venous blood from the pulmonary veins which is from the pulmonary veins which is rich in oxygen and low in CO2rich in oxygen and low in CO2
Left AtriumLeft Atrium
Mitral Valve – Blood passes from the Mitral Valve – Blood passes from the left atrium to the left ventricle via left atrium to the left ventricle via this valvethis valve
Left VentricleLeft Ventricle
Thickest and strongest chamberThickest and strongest chamber
Left VentricleLeft Ventricle
Forms the apex of the heartForms the apex of the heart
Left VentricleLeft Ventricle
Blood passes from the left ventricle Blood passes from the left ventricle through the aortic valve into the through the aortic valve into the aortaaorta
Left VentricleLeft Ventricle
During fetal life the ductus arteriosus During fetal life the ductus arteriosus shunts blood from the pulmonary shunts blood from the pulmonary trunk into the aortatrunk into the aorta
Left VentricleLeft Ventricle
At birth the ductus arteriosus closes At birth the ductus arteriosus closes and becomes the ligamentum and becomes the ligamentum arteriosumarteriosum
Left VentricleLeft Ventricle
The left ventricle is separted from The left ventricle is separted from the right ventricle by the the right ventricle by the interventricular septuminterventricular septum
Myocardial Thickness and Myocardial Thickness and FunctionFunction
The atria walls are thin because they The atria walls are thin because they only pump blood to the nearby only pump blood to the nearby ventriclesventricles
Myocardial Thickness and Myocardial Thickness and FunctionFunction
The ventricle wall are thicker The ventricle wall are thicker because they pump blood greater because they pump blood greater distancesdistances
Myocardial Thickness and Myocardial Thickness and FunctionFunction
The right ventricle walls are thinner The right ventricle walls are thinner than the left because they pump than the left because they pump blood to the nearby lungs blood to the nearby lungs
Myocardial Thickness and Myocardial Thickness and FunctionFunction
The left ventricle walls are thicker The left ventricle walls are thicker because they pump blood through because they pump blood through the bodythe body
Function of Heart ValvesFunction of Heart Valves
Valves open and close in response to Valves open and close in response to pressure changes as the heart pressure changes as the heart contracts and relaxescontracts and relaxes
Myocardial Thickness and Myocardial Thickness and FunctionFunction
Two types of valves;Two types of valves;
1.1. Atrioventricular ValvesAtrioventricular Valves
2.2. SemilunarSemilunar
Atrioventricular ValvesAtrioventricular Valves
1.1. Tricuspid (right side)Tricuspid (right side)
2.2. Mitral or bicuspid (left side)Mitral or bicuspid (left side)
Atrioventricular ValvesAtrioventricular Valves
AV valves prevent blood flow from AV valves prevent blood flow from the ventricles back into the atriathe ventricles back into the atria
Atrioventricular ValvesAtrioventricular Valves
Back flow is prevented by the Back flow is prevented by the contraction of papillary muscles and contraction of papillary muscles and tightening the chordae tendinaetightening the chordae tendinae
Semilunar ValvesSemilunar Valves
SL valves allow ejection of blood SL valves allow ejection of blood from the heart into the pulmonary from the heart into the pulmonary arteries and aortaarteries and aorta
Semilunar ValvesSemilunar Valves
Prevent back flow into the ventriclesPrevent back flow into the ventricles
Circulation of BloodCirculation of Blood
1.1. Systemic Systemic
2.2. PulmonaryPulmonary
3.3. CoronaryCoronary
Systemic CirculationSystemic Circulation
The left side of the heart pumps The left side of the heart pumps oxygenated blood from the left oxygenated blood from the left ventricle into the ascending aorta.ventricle into the ascending aorta.
Systemic CirculationSystemic Circulation
The coronary arteries arise off of the The coronary arteries arise off of the ascending aortaascending aorta
Pulmonary CirculationPulmonary Circulation
The right side of the heart receives The right side of the heart receives deoxygenated blood from the body.deoxygenated blood from the body.
Pulmonary CirculationPulmonary Circulation
The right side of the heart pumps The right side of the heart pumps blood from the right ventricle and blood from the right ventricle and sends it into the lungs via the sends it into the lungs via the pulmonary arterypulmonary artery
Circulation of BloodCirculation of Blood
Right atrium receives blood from the Right atrium receives blood from the superior and inferior vena cavasuperior and inferior vena cava
Circulation of BloodCirculation of Blood
The Left atrium receives blood from The Left atrium receives blood from the pulmonary veinsthe pulmonary veins
Coronary CirculationCoronary Circulation
It delivers oxygenated blood and It delivers oxygenated blood and nutrients to and removes CO2 and nutrients to and removes CO2 and wastes from the myocardiumwastes from the myocardium
Coronary CirculationCoronary Circulation
The The left and right coronary left and right coronary arteriesarteries branch from the ascending branch from the ascending aorta and carry oxygenated bloodaorta and carry oxygenated blood
Coronary CirculationCoronary Circulation
Left coronary artery branches into Left coronary artery branches into the;the;
1.1. Left anterior descending arteryLeft anterior descending artery
2.2. Circumflex arteryCircumflex artery
Coronary CirculationCoronary Circulation
Right coronary artery branches into;Right coronary artery branches into;
1.1. Marginal arteryMarginal artery
2.2. Posterior descending arteryPosterior descending artery
Coronary CirculationCoronary Circulation
Deoxygenated blood returns to the Deoxygenated blood returns to the right atrium through the coronary right atrium through the coronary sinussinus
Histology of Cardiac MuscleHistology of Cardiac Muscle
In comparison to skeletal muscle In comparison to skeletal muscle fibers, cardiac muscle fibers are fibers, cardiac muscle fibers are involuntary, shorter in length, larger involuntary, shorter in length, larger in diameter, and squarish rather than in diameter, and squarish rather than circular in transverse section.circular in transverse section.
Histology of Cardiac MuscleHistology of Cardiac Muscle
They also exhibit branchingThey also exhibit branching
Histology of Cardiac MuscleHistology of Cardiac Muscle
Have same arrangement of actin and Have same arrangement of actin and myosin, and the same bands, zones, myosin, and the same bands, zones, and Z discs as skeletal musclesand Z discs as skeletal muscles
Cardiac Conduction SystemCardiac Conduction System
There is an atrial and ventricular There is an atrial and ventricular networknetwork
Cardiac Conduction SystemCardiac Conduction System
Fibers within the networks are Fibers within the networks are connected by intercalated discsconnected by intercalated discs
Cardiac Conduction SystemCardiac Conduction System
The intercalated discs allow the The intercalated discs allow the fibers to work together so that each fibers to work together so that each network serves as a functional unitnetwork serves as a functional unit
Cardiac Conduction SystemCardiac Conduction System
Cardiac muscle cells are Cardiac muscle cells are autorhythmic cells because they are autorhythmic cells because they are self-excitable.self-excitable.
Cardiac Conduction SystemCardiac Conduction System
They repeatedly generate They repeatedly generate spontaneous action potentials that spontaneous action potentials that then trigger heart contractionthen trigger heart contraction
Cardiac Conduction SystemCardiac Conduction System
The components of this system are;The components of this system are;
1.1. Sinoatrial node (SA)Sinoatrial node (SA)
2.2. Atrioventricular node (AV)Atrioventricular node (AV)
3.3. Bundle of HisBundle of His
4.4. Right and Left Bundle branchesRight and Left Bundle branches
5.5. Purkinje fibersPurkinje fibers
Cardiac Conduction SystemCardiac Conduction System
SA node is the pacemaker SA node is the pacemaker
Cardiac Conduction SystemCardiac Conduction System
From the SA node, a cardiac action From the SA node, a cardiac action potential travels throughout the potential travels throughout the atrial muscle and down to the AV atrial muscle and down to the AV nodenode
Cardiac Conduction SystemCardiac Conduction System
At the AV node the impulse is At the AV node the impulse is delayed (about 0.1sec)delayed (about 0.1sec)
Cardiac Conduction SystemCardiac Conduction System
This gives the atria time to This gives the atria time to completely contract before completely contract before ventricular contraction beginsventricular contraction begins
Cardiac Conduction SystemCardiac Conduction System
It then passes through the Bundle of It then passes through the Bundle of His, Right and Left Bundle Branches, His, Right and Left Bundle Branches, and the Purkinje fibers, resulting in and the Purkinje fibers, resulting in ventricular contractionventricular contraction
Cardiac CycleCardiac Cycle
Consists of;Consists of;
1.1. Systole (contraction) and Diastole Systole (contraction) and Diastole (relaxation) of both atria(relaxation) of both atria
2.2. Systole and Diastole of both Systole and Diastole of both ventriclesventricles
Atrial DiastoleAtrial Diastole
The atria are relaxedThe atria are relaxed
Atrial DiastoleAtrial Diastole
They receive blood from three veinsThey receive blood from three veins
Atrial DiastoleAtrial Diastole
The A-V valves are open, allowing for The A-V valves are open, allowing for 70% of ventricular filling. The 70% of ventricular filling. The ventricles are therefore also in ventricles are therefore also in diastole.diastole.
Atrial SystoleAtrial Systole
The SA node then fires; after this The SA node then fires; after this electrical event, atrial systole begins electrical event, atrial systole begins (a mechanical event)(a mechanical event)
Atrial SystoleAtrial Systole
Atrial contraction accounts for 30% Atrial contraction accounts for 30% of ventricular fillingof ventricular filling
Ventricular SystoleVentricular Systole
Shortly after the beginning of Shortly after the beginning of ventricular depolarization, ventricular ventricular depolarization, ventricular systole beginssystole begins
Ventricular SystoleVentricular Systole
The ventricles contract. The The ventricles contract. The ventricular pressure becomes higher ventricular pressure becomes higher than atrial pressures, causing the AV than atrial pressures, causing the AV valves to close.valves to close.
Ventricular SystoleVentricular Systole
The SL valves open when the The SL valves open when the ventricular pressure becomes higher ventricular pressure becomes higher than aortic (pulmonary arterial) than aortic (pulmonary arterial) pressure.pressure.
Ventricular SystoleVentricular Systole
Then blood is ejected into the aorta Then blood is ejected into the aorta and pulmonary trunk.and pulmonary trunk.
Ventricular DiastoleVentricular Diastole
Begins when the ventricles relaxBegins when the ventricles relax
Ventricular DiastoleVentricular Diastole
Ventricular pressures drop below Ventricular pressures drop below arterial pressures, causing the SL arterial pressures, causing the SL valves to closevalves to close
Ventricular DiastoleVentricular Diastole
The ventricular pressures continue to The ventricular pressures continue to drop below atrial pressures, causing drop below atrial pressures, causing the AV valves to openthe AV valves to open
AuscultationAuscultation
Listening to sounds within the body Listening to sounds within the body with a stethoscopewith a stethoscope
AuscultationAuscultation
The first heart sound (lubb) is The first heart sound (lubb) is created by the closing of the AV created by the closing of the AV valves soon after ventricular systole valves soon after ventricular systole beginsbegins
AuscultationAuscultation
The second heart sound (dupp) The second heart sound (dupp) represents the closing of the SL represents the closing of the SL valves close to the end of the valves close to the end of the ventricular systole.ventricular systole.
Cardiac OutputCardiac Output
The volume of blood ejected from the The volume of blood ejected from the left ventricle (or the right ventricle) left ventricle (or the right ventricle) into the aorta (or pulmonary trunk) into the aorta (or pulmonary trunk) each minute.each minute.
Cardiac OutputCardiac Output
Cardiac Output = Stroke volume X Cardiac Output = Stroke volume X Heart RateHeart Rate
Cardiac OutputCardiac Output
Stroke volume – the volume of blood Stroke volume – the volume of blood ejected by the ventricle with each ejected by the ventricle with each contractioncontraction
Cardiac OutputCardiac Output
Stroke Volume = End Diastolic Stroke Volume = End Diastolic Volume (130ml) – End Systolic Volume (130ml) – End Systolic Volume (60ml)Volume (60ml)
Cardiac OutputCardiac Output
Heart Rate – number of beats per Heart Rate – number of beats per minuteminute
Regulation of Heart RateRegulation of Heart Rate
Sympathetics impulses increase Sympathetics impulses increase heart rate and force of contractionheart rate and force of contraction
Regulation of Heart RateRegulation of Heart Rate
Parasympathetic impulses decrease Parasympathetic impulses decrease heart rateheart rate
TachycardiaTachycardia
Heart Rate over 100 beats/minHeart Rate over 100 beats/min
BradycardiaBradycardia
Heart Rate below 60 beats/minHeart Rate below 60 beats/min
FibrillationFibrillation
Prolonged tachycardiaProlonged tachycardia
Exercise And The HeartExercise And The Heart
Sustained exercise increases oxygen Sustained exercise increases oxygen demand in musclesdemand in muscles
Exercise And The HeartExercise And The Heart
Resting cardiac output 5.25 Resting cardiac output 5.25 Liters/minuteLiters/minute
Exercise And The HeartExercise And The Heart
In sedentary people CO may go up to In sedentary people CO may go up to 22 liters/minute22 liters/minute
Exercise And The HeartExercise And The Heart
In trained athletes CO may go up to In trained athletes CO may go up to 40 liters/minute40 liters/minute
Exercise And The HeartExercise And The Heart
Sedentary people increase their CO Sedentary people increase their CO during exercise by an increase in HR during exercise by an increase in HR and SVand SV
Exercise And The HeartExercise And The Heart
Sedentary peopleSedentary people Increase in HR more dramaticIncrease in HR more dramatic Stroke volume only goes up by 10-Stroke volume only goes up by 10-
35%35%
Exercise And The HeartExercise And The Heart
For a given activity, sedentary For a given activity, sedentary people’s maximum HR will be higher people’s maximum HR will be higher than in a trained athletethan in a trained athlete
Exercise And The HeartExercise And The Heart
Trained athletes increase their CO Trained athletes increase their CO during exercise by an increase in HR during exercise by an increase in HR and SVand SV
Exercise And The HeartExercise And The Heart
Trained AthletesTrained Athletes Increase in SV more dramatic than Increase in SV more dramatic than
HRHR Their SV goes up to 60%Their SV goes up to 60%
Exercise And The HeartExercise And The Heart
Athletes have larger stroke volumes Athletes have larger stroke volumes due to longer filling time due to longer filling time
Electrocardiogram (ECG or Electrocardiogram (ECG or EKG)EKG)
Records the electrical currents of the Records the electrical currents of the body generated by the heartbody generated by the heart
Electrocardiogram (ECG or Electrocardiogram (ECG or EKG)EKG)
P= depolarization of the atriaP= depolarization of the atria
Electrocardiogram (ECG or Electrocardiogram (ECG or EKG)EKG)
QRS= depolarization of the ventriclesQRS= depolarization of the ventricles
(repolarization of atria, but don’t see)(repolarization of atria, but don’t see)
Electrocardiogram (ECG or Electrocardiogram (ECG or EKG)EKG)
T= ventricles repolarizationT= ventricles repolarization
Electrocardiogram (ECG or Electrocardiogram (ECG or EKG)EKG)
PR interval= between beginning of PR interval= between beginning of atrial depolarization and ventrical atrial depolarization and ventrical depolarizationdepolarization
Electrocardiogram (ECG or Electrocardiogram (ECG or EKG)EKG)
ST segment= ventricle contractionST segment= ventricle contraction
Electrocardiogram (ECG or Electrocardiogram (ECG or EKG)EKG)
QT interval = ventricle depolarization QT interval = ventricle depolarization through ventricle repolarizationthrough ventricle repolarization