cardiovascular system - makes up about 95% of the heart and
responsible for the heart to contract
Cardiovascular System 3. Endocardium
● Compose of the: heart, blood, blood vessels - innermost layer, provides lining for the
● The heart of a healthy adult, at rest, pumps chambers of the heart
approximately 5 liters (L) of blood per minute.
● The heart is actually two pumps in one. The Heart chambers and internal anatomy
RIGHT SIDE of the heart pumps blood to the
lungs and back to the left side of the heart through Atria
vessels of the pulmonary circulation. ● Thin-walled, superior and posterior part of the
● The LEFT SIDE of the heart pumps blood to all heart
other tissues of the body and back to the right ● Receiving or entrance chambers not important in
side of the heart through vessels of systemic the pumping activity of the heart
circulation. ● The atria function primarily as reservoirs.
● R atrium has three major openings: inferior and
HEART superior vena cava , coronary sinus
● L atrium has 4 openings,
● Size, shaped and location: ○ (4 pulmonary veins)
● Shaped like a blunt cone, apprx size of a close ● The two atria are separated from each other by a
fist, larger in physically active adults partition called the
● Generally decreases in size apprx at age 65 ● interatrial (between the atria) septum.
● Located in the thoracic cavity between the lungs, Ventricles
directed to the left of the midline of mediastinum, - thick-walled, anterior and inferior part of the hear
2/3 of its mass lies to the left. discharging chambers or actual pumps of the
● Lies obliquely in the mediastinum heart
● APEX, blunt rounded point of the cone, directed
anteriorly and inferior ● when they contract, blood is propelled out of the
● BASE, part opposite the end of cone apex, heart and into circulation
directed posteriorly and superior, 2nd intercostals ● LV is thicker than the RV
space, 7-9 cm left of the sternum ● L ventricle forms the heart apex
● The heart of a healthy adult, at rest, pumps ● Interventricular septum: divides the heart
approximately 5 liters (L) of blood per minute. longitudinally, between 2 ventricles
● RV opens into the pulmonary trunk
● LV opens into the aorta
● However, the left and right ventricles pump nearly
Chambers of the Heart: the same volume of blood.
● The higher pressure generated by the left
● Four Chambers of the heart: 2 atrium, 2 ventricle moves blood through the larger systemi
ventricles circulation
● Each chamber is lined with endocardium ● whereas the lower pressure generated by the
right ventricle moves blood through the smaller
What are the clinical reasons why we need to know the pulmonary circulation.
location of the heart?
Atrioventricular Valves:
Heart Wall - Composed of cusps or flaps
- Pericardium or pericardial sac: double-layered - Allows blood to flow from the atria and ventricles
closed sac that surrounds and protects the heart - Prevent blood flowing back into the atria
Layers of the Heart Wall: 1. Tricuspid valve: has 3 cusps, located between R
1. Epicardium atrium and R ventricle
- external layer, thin transparent outer layer of the 2. Bicuspid or Mitral valve: has 2 cusps located
heart wall. (smooth, slippery texture) between L atrium and L ventricle
2. Myocardium: thick middle layer
responsible for the heart to contract
Cardiovascular System 3. Endocardium
● Compose of the: heart, blood, blood vessels - innermost layer, provides lining for the
● The heart of a healthy adult, at rest, pumps chambers of the heart
approximately 5 liters (L) of blood per minute.
● The heart is actually two pumps in one. The Heart chambers and internal anatomy
RIGHT SIDE of the heart pumps blood to the
lungs and back to the left side of the heart through Atria
vessels of the pulmonary circulation. ● Thin-walled, superior and posterior part of the
● The LEFT SIDE of the heart pumps blood to all heart
other tissues of the body and back to the right ● Receiving or entrance chambers not important in
side of the heart through vessels of systemic the pumping activity of the heart
circulation. ● The atria function primarily as reservoirs.
● R atrium has three major openings: inferior and
HEART superior vena cava , coronary sinus
● L atrium has 4 openings,
● Size, shaped and location: ○ (4 pulmonary veins)
● Shaped like a blunt cone, apprx size of a close ● The two atria are separated from each other by a
fist, larger in physically active adults partition called the
● Generally decreases in size apprx at age 65 ● interatrial (between the atria) septum.
● Located in the thoracic cavity between the lungs, Ventricles
directed to the left of the midline of mediastinum, - thick-walled, anterior and inferior part of the hear
2/3 of its mass lies to the left. discharging chambers or actual pumps of the
● Lies obliquely in the mediastinum heart
● APEX, blunt rounded point of the cone, directed
anteriorly and inferior ● when they contract, blood is propelled out of the
● BASE, part opposite the end of cone apex, heart and into circulation
directed posteriorly and superior, 2nd intercostals ● LV is thicker than the RV
space, 7-9 cm left of the sternum ● L ventricle forms the heart apex
● The heart of a healthy adult, at rest, pumps ● Interventricular septum: divides the heart
approximately 5 liters (L) of blood per minute. longitudinally, between 2 ventricles
● RV opens into the pulmonary trunk
● LV opens into the aorta
● However, the left and right ventricles pump nearly
Chambers of the Heart: the same volume of blood.
● The higher pressure generated by the left
● Four Chambers of the heart: 2 atrium, 2 ventricle moves blood through the larger systemi
ventricles circulation
● Each chamber is lined with endocardium ● whereas the lower pressure generated by the
right ventricle moves blood through the smaller
What are the clinical reasons why we need to know the pulmonary circulation.
location of the heart?
Atrioventricular Valves:
Heart Wall - Composed of cusps or flaps
- Pericardium or pericardial sac: double-layered - Allows blood to flow from the atria and ventricles
closed sac that surrounds and protects the heart - Prevent blood flowing back into the atria
Layers of the Heart Wall: 1. Tricuspid valve: has 3 cusps, located between R
1. Epicardium atrium and R ventricle
- external layer, thin transparent outer layer of the 2. Bicuspid or Mitral valve: has 2 cusps located
heart wall. (smooth, slippery texture) between L atrium and L ventricle
2. Myocardium: thick middle layer
