Pericardium and Heart Flashcards
(29 cards)
What is pericardium?
The pericardium is afibro-serous, double walled fluid-filled sack that surrounds the muscular body of the heart and the roots of the great vessels
What are the great vessels?
The aorta, pulmonary artery, pulmonary veins, and the superior and inferior vena cava.
What is fibrous pericardium attached to?
Central tendon of diaphragm and the sternum
Where does pericardium receive its nerve supply from?
Phrenic nerves supply diaphragm and gives branches to supply fibrous and parietal pericardium
Name the four physiological roles of pericardium
Fixes the heart, prevents overfilling, lubrication, protection from infection
How does pericardium fix the heart?
Fixes heart in mediastinum and limits its motion
How does pericardium prevent overfilling of heart?
The relatively inextensible fibrous layer of the pericardium prevents the heart from increasing in size too rapidly
How does pericardium help lubrication?
A thin film of fluid between the two layers of the serous pericardium reduces the friction generated by the heart as it moves within the thoracic cavity
How does pericardium help lubrication?
A thin film of fluid between the two layers of the serous pericardium reduces the friction generated by the heart as it moves within the thoracic cavity
How does pericardium protect from infection?
The fibrous pericardium serves as a physical barrier between the muscular body of the heart and adjacent organs prone to infection, such as the lungs
How many layers form the wall of the heart?
3, they are the epicardium, myocardium and endocardium
Epicardium
Outermost layer of the heart, formed by the visceral layer of the pericardium
Composed of connective tissue and fat
Myocardium
Myocardium is composed of cardiac muscle and is an involuntary striated muscle
The myocardium is responsible for contractions of the heart
Endocardium
The innermost layer of the cardiac wall is known as the endocardium
Endocardium lines the cavities and valves of the heart\
Describe the heart
Muscular organ in most animals
Pumps blood through blood vessels of circulatory system
Pumped blood carries oxygen and nutrients to body
Metabolic waste such as co2 is carried to lungs
Approximately size of closed fist
Where is the great cardiac vein?
In the anterior interventricular sulcus of the heart is the great cardiac vein
What does right atrium consist of?
Main cavity and a small out-pouching, the auricle
What is junction between the right atrium and the right auricle called?
This depression id the sulcus terminalis
What is internal ridge of sulcus terminalis called?
Crista terminalis
What is the part of the atrium in front of the ridge roughened by?
Muscle fibers, musculi pectinati- run from the crista terminalis to the auricle
Name the openings in the right atrium
Superior vena cava
inferior vena cava
coronary sinus
anterior cardiac veins
right atrioventricular orifice
Superior vena cava
returns the blood from the upper half of the body
inferior vena cava
returns blood from the lower half of the body
coronary sinus
drains most of the blood from the heart wall, opens into the right atrium
