2. • It is a cone-shaped hollow muscular organ which pumps blood to the
body and back.
• It has weight about 250-300 grams.
• Size is that of a fist: 12cm length, 8cm wide, 6cm thick
• Location: -in middle mediastinum.
-1/3rd to right of midsternal plane and 2/3rd to left of it.
-posterior to body of sternum and 2nd-6th costal cartilages.
-anterior to vertebral column at level of T5-T8
-superior to superior surface of diaphragm.
3. • Base -quadrilateral directed upward, backward and posteriorly
-made of –left atrium
--parts of right atrium
• Apex –directed forward, downward and to left
-made of –parts of left ventricle
4. • 4 Surfaces: sternocostal/anterior surface- consist of right ventricle, some right atrium, some left ventricle.
diaphragmatic/inferior surface- consist of left ventricle, some right ventricle.
left pulmonary surface- consist of left atrium and left ventricle.
right pulmonary surface- consist of right atrium.
• 4 Margins: right margin
left margin
inferior/ acute margin- between anterior and diaphragmatic surfaces
obtuse margin- between anterior and left pulmonary surfaces
• 4 Grooves: coronary sulci- divide atria from ventricles
interatrial groove- divide left and right atria
interventricular grooves - anterior
- posterior
5. FUNCTION
• Pumps blood throughout the body via the circulatory system.
• Supply oxygenated blood with nutrients to tissues.
• Remove carbon dioxide and other wastes therefore receive
deoxygenated blood from body.
6. HEART WALL
• The Heart has three layers from inside to
outside: endocardium, myocardium,
epicardium.
• All these are surrounded by a double-
membrane sac of Pericardium.
7. PERICARDIUM AND EPICARDIUM
• It has 2 components:
• 1) Fibrous pericardium- outer tough connective tissue
• 2) Serous pericardium- inner thin layer, has 2 layers – Parietal layer- line
inner surface of fibrous pericardium
--Visceral layer-
attached to heart {EPICARDIUM}
• In between these two present the pericardial cavity having serous fluid.
• It allow lubrication of heart for friction-free movements.
• Prevent overfilling of heart with blood.
8. MYOCARDIUM
• The middle layer of the heart wall, thickest
• Cardiac muscle- involuntary striated muscle tissue surrounded by
collagen.
• The cardiac muscle pattern- muscle cells swirl and spiral around
the chambers of the heart, with the outer muscles forming a
figure 8 pattern around the atria and around the bases of the
great vessels and the inner muscles, forming a figure 8 around
the two ventricles and proceeding toward the apex. This complex
swirling pattern allows the heart to pump blood more effectively
9. ENDOCARDIUM
• The innermost layer.
• Lining of simple squamous epithelium.
• Covers heart chambers and valves and is continuous with the
endothelium of the veins and arteries of the heart.
• Secrete Endothelin- regulate contraction of the myocardium.
• Conduction system is present here.
10. CHAMBERS
• Heart has 4 chambers divided by the grooves, septum and valves.
• Right Heart: right atrium and right ventricle
• Left Heart: left atrium and left ventricle
• There are interatrial septum, interventricular septum, and
atrioventricular septum.
• There are bicuspid (mitral) valve, tricuspid (bazian) valve, aortic valve and
pulmonary valve.
11. RIGHT HEART
• Right atrium is separated by right ventricle by atrioventricular septum and
tricuspid valve (ant., septal, post cusps).
• Right Atrium: has right auricle, pectinate muscles around wall
-has opening of inferior and superior vena cava, coronary sinus
- in interatrial septum, Fossa Ovalis is present.
• Right Ventricle: has papillary muscles
- has chordae tendineae which attach to tricuspid valve
-receive blood from right atrium and pass to pulmonary trunk
-semilunar pulmonary valve (right, left, ant. Cusps) is present at
opening of pulmonary trunk
12. LEFT HEART
• Left atrium is separated from left ventricle by atrioventricular septum and
bicuspid valve (ant , post cusps).
• Left Atrium: has left auricle, pectinate muscles around wall
- has opening of pulmonary veins carrying oxygenated blood
• Left Ventricle: has papillary muscles
- has chordae tendineae attached to bicuspid valve
-receive blood from left atrium and pass to aorta
-semilunar aortic valve (right, left, post cusps) is present at
opening of aorta
- wall is 3 times thicker than of right ventricle
13.
14. CIRCULATORY SYSTEM
• It include heart, lungs and vessels.
• The Heart has double circulation: pulmonary circulation and
systemic circulation
15. PULMONARY CIRCULATION
• Begin from right ventricle ->> deoxygenated blood goes through pulmonary arteries ->> to lungs ->> oxygenation occur and
waste and carbon dioxide exhaled from body ->> oxygenated blood goes through pulmonary veins ->> to left atrium.
16. SYSTEMIC CIRCULATION
• Begin from left ventricle ->> oxygenated blood goes through
aorta ->> to body ->> transfer oxygen and nutrients to tissues
and become deoxygenated ->> deoxygenated blood goes
through inferior and superior vena cava and coronary sinus -
>> to right atrium.
17. CONDUCTION SYSTEM OF HEART
• Cardiac muscle cells have capacity of generating self-impulse.
• 1st Sino-Atrial Node: pacemaker, located at upper right corner of
right atrium, generate action potential and cause atrial systole.
• 2nd Atrio-Ventricular Node: located in right atrium near interatrial
septum, delay the signal.
• Between these 2 are present internodal pathways.
• 3rd Bundle of Hiss: AV bundle, located in interventricular septum, has
right and left bundle branches.
• 4th Purkinje Fibers: located in right and left ventricles, cause
ventricular systole.
18. CARDIAC CYCLE• Sequence of events that occurs when the heart beats.
• One cardiac Cycle is of 0.8 seconds.
• As the heart beats, it circulates blood through pulmonary and systemic
circuits of the body.
• There are two phases of the cardiac cycle: systolic and diastolic
• For 1st 0.1 sec. – atrial systole; rest 0.7 sec. – atrial diastole,
• after 0.1 sec, up to 0.3 sec. – ventricular systole; rest 0.5 sec. –
ventricular diastole
• Represented by ECG
• During systole- semilunar valves are open and atrioventricular valves are
closed. Closing of atrioventricular valves produce 1st heart sound ‘LUB’.
• During diastole- atrioventricular valves are open and semilunar valves
are closed. Closing of semilunar valves produce 2nd heart sound ‘DUB’.
19.
20. VASCULATURE OF HEART
• Arteries:
• 1) Right coronary artery- supply right atrium and
posterior surface of both ventricles.
• Branches- marginal artery
- posterior interventricular artery
• 2) Left coronary artery- supply left atrium and ventricle.
• Branches- circumflex artery
- anterior interventricular artery
21. • Veins:
• Coronary sinus- receive blood from – great cardiac vein
- anterior cardiac vein
- middle cardiac vein
- small cardiac vein
22. INNERVATION
• Vagus nerve
• Sympathetic trunk
• These nerves form a network of nerves that lies over
the heart called the cardiac plexus.
23. CLINICAL CASES
• Heart Arrhythmia :
• Condition of irregular heart beat.
• Causes- Coronary artery disease.
-High blood pressure.
-cardiomyopathy
-Valve disorders.
-Electrolyte imbalances in the blood, such as
sodium or potassium.
24. • Cardiogenic Shock:
• condition in which heart suddenly can't pump enough blood to meet body's needs.
• Causes- damage to heart's right ventricle, which sends blood to lungs to receive oxygen.
- myocardial infarction
-pulmonary embolism
-pericardial tamponade
-sudden valvular regurgitation
-inability of heart muscle to work properly
-ventricular tachycardia.
25. • Keshan disease:
• congestive cardiomyopathy caused by a combination of dietary
deficiency of selenium and the presence of a mutated strain of
Coxsackievirus.
• Found in the areas with low selenium in the soil.
• Can cause- hypothyroidism, including extreme fatigue, mental
slowing, goiter, cretinism, and recurrent miscarriage
26. • Eisenmenger's syndrome:
• long-standing left-to-right cardiac shunt in interventricular
septum caused by a congenital heart defect causes pulmonary
hypertension
• Result into- Cyanosis
-High red blood cell count
-clubbed finger tips
-Heart failure
-Abnormal heart rhythms
-Iron deficiency
-Kidney problems
-Stroke
