The cardiovascular system consists of the heart, blood vessels, and blood. The heart is a hollow muscular organ located in the chest that pumps blood through two circuits: systemic circulation and pulmonary circulation. It has four chambers - right and left atria and ventricles separated by valves. Blood vessels include arteries, which carry blood away from the heart, and veins, which carry blood back to the heart. The cardiovascular system also contains a conduction system that initiates and regulates the heartbeat, starting with the sinoatrial node. Blood vessels have three layers - tunica intima, media, and externa - that vary in thickness and composition between arteries and veins.
5. Gross Anatomy
โข Conical hollow muscular organ
โข 12 x 9 cm and weighs 300g males 250g
females
โข 4 chambers
โ Right and left atria
โ Right and left ventricles
โข Septum
โ Interatrial septum
โ Interventricular septum
7. Pericardium
โข Fibroserous sac
โ encloses heart and roots of the great vessels
โข Consists of
โ Fibrous pericardium
โ Serous pericardium
โข Parietal layer โ fused with fibrous pericardium
โข Visceral layer โ fused to the heart
9. Pericardial Cavity
โข Pericardial cavity
โ Potential space between the parietal pericardium
and visceral pericardium
โ Contains thin film of serous fluid
10. Wall of the Heart
โข Three layers
โ Epicardium
โ Myocardium
โ Endocardium
11. Position of the Heart
โข Obliquely behind the body of the sternum
โข 1/3 right to the median plane other 2/3 left to
the median plane
โข Apex of the Heart
โ Formed by left ventricle
โ Directed downward, forward to the left
โ Left 5th intercostal space 3 ยฝ inches lateral to
midsternal line (just medial to the left
midclavicular line)
12. โข Base of the Heart
โ Formed by left atrium and small part of right
atrium
โ Opening of pulmonary veins
โ Forms posterior surface of the heart
13. Right Atrium
โข External extension โ right auricle
โข 3 main openings
โ Superior vena cava
โ Inferior vena cava
โ Coronary sinus
โข Interior
โ Smooth posterior part
โ Rough anterior/pectinate part ( musculi pectinati)
โ Septal wall
โข Receive blood from the whole body and pumps to
right ventricle through right AV orifice
14.
15. Left atrium
โข External extension โ left auricle
โข Two Pulmonary veins opens into the atrium
each side of the posterior wall
โข Interior
โ Greater part smooth
โ Musculi Pectinati - auricle
โข Receive oxygenated blood from the lungs
โ 4 pulmonary veins
โข Pumps to left ventricle through left AV orifice
16.
17. Right Ventricle
โข Receive blood from the right atrium
โข Pumps to the lungs through pulmonary artery
โข Interior
โ Rough part ( inflowing part)โ trabecular carneae
โข Papillary muscles โ finger like projections from the
ventricle wall
โ Other end connects to cusps of AV valves through chordae
tendinae
โ Smooth part ( out flowing part)- infundibulum
โ 2 orifices โ tricuspid, pulmonary
18.
19. Left Ventricle
โข
โข
โข
โข
Receive oxygenated blood from the left atrium
Pumps into the aorta
Forms apex of the heart
Interior
โ Rough part (inflowing)
โ Smooth part(outflow) โ Aortic vestibule
โ 2 orifices โ mitral , aortic
โข Wall Thickness โ Left ventricle>>> Right
Ventricle
21. Valves of the Heart
โข 2 types of valves
โข Atrioventricular Valves
โ Left โ bicuspid / mitral ( 2flaps)
โ Right โ tricuspid ( 3flpas)
โ Papillary muscles and chordae tendinae prevent
them from eversion towards atria
โข Semilunar Valves- aortic and pulmonary
โ 3 cusps โ directly attached to vessel wall
โ Blood caught in cusps push them to close position
30. Conduction system of the Heart
โข Consists of modified cardiac muscle cells
which are specialized for initiation and
conduction of cardiac impulse
โข Consists of
โ SA node
โข cardiac pacemaker โ impulse 70/min
โข Located at junction of SVC at right atrium
โ AV node
โข Located at right posterior part of interatrial septum
โข Only conduction pathway between atria and ventricles