ANATOMY AND PHYSIOLOGY Flashcards
What are the 5 surfaces of the heart?
Base
Diaphragmatic (inferior)
Sternocostal (anterior)
Left pulmonary surface
Right pulmonary surface
What are the 4 heart chambers and what are their functions?
Right atrium and ventricle - recieve deoxygenated blood from systemic veins and pumps it to the lungs
Left atrium and ventricle - recieve oxygenated blood from the lungs and pumps it to the systemic vessels
What separates the left and right sides of the heart?
Interatrial and interventricular septa
What separates the atria and ventricles?
Atrioventricular septa
What prevents backward prolapse of the cusps of the valves?
Chordae tendinae (fibrous cords that connect the papillary muscles of the ventricular wall to the atrioventricular valves)
What are the 2 sets of valves?
Atrioventricular (prevent back flow from ventricles to atria) and semilunar (prevent back flow from the great vessels into ventricles)
What are the 2 atrioventricular valves and describe their structure?
Right atrioventricular valve - tricuspid valve - has 3 cusps which are anterior, septal and posterior
Left atrioventricular valve - bicuspid valve - has 2 cusps which are anterior and posterior
LAB RAT
What are the 2 semilunar valves and describe their structure?
The pulmonary semilunar valve - between right ventricle and opening of pulmonary trunk - has 2 semilunar cusps (anterior, left and right)
The aortic semilunar valve - between left ventricle and opening of aorta - has 3 semilunar cusps (left, right and posterior)
Outline the blood flow through the heart?
The right atrium receives deoxygenated blood from the superior and inferior venae cavae and coronary sinus
The right atrium contracts pushing blood through the right atrioventricular valve into the right ventricle. The right ventricle then contracts passing the blood into the pulmonary trunk via the pulmonary valve to reach the lungs
In the lungs, the blood gets oxygenated then moves back into the heart entering the left atrium through the pulmonary veins.
The left atrium contracts and pushes the blood into the left ventricle through the left atrioventricular valve.
The left ventricle pushes oxygenated blood through the aortic semilunar valve into the aorta, from which blood is distributed throughout the body.
What supplies the heart with oxygenated blood?
The left and right coronary arteries
Where do the coronary arteries arise from?
Aortic sinuses at the beginning of the ascending aorta
What collects venous blood from the heart?
The middle, posterior and small cardiac veins
What are the great vessels of the heart?
Aorta
Pulmonary artery
Pulmonary vein
Superior vena cava
Inferior vena cava
What are the major branches of the aorta?
Brachiocephalic trunk
Left common carotid artery
Left subclavian artery
Whats the weight of a normal heart in males and females?
Males - 310g
Females - 255g
What are the 3 layers of the heart wall?
Epicardium - outer layer formed by the visceral layer of the serous pericardium
Myocardium - contains the excitable tissue and conducting system
Endocardium
Which coronary artery carries 80% of the flow to the heart muscles?
Left main coronary artery
What are the branches of the left coronary artery and what do they supply?
Left anterior descending - its diagonal branches supply the interventricular septum and both ventricles
Circumflex coronary artery - typically gives rise to the left marginal artery and other small arteries. Supplies blood to the lateral and posterior portions of the left ventricle and left atrium
What are the branches of the right coronary artery?
Anterior branches - Conal artery, sinus node branch, anterior atrial branch, anterior ventricular branch
Marginal branches - right acute marginal branch
Inferior branches - atrioventricular nodal branch, posterior descending artery, posterolateral branch
What does the right marginal atrery supply?
Lateral portion of right ventricle and apex
What does the posterior descending artery supply?
Inferior aspect of the heart
What does the right coronary aretry supply?
Right atrium and ventricle
Where do most coronary veins coalesce?
Coronary sinus (runs in the left posterior atrioventricular groove and opens into the right atrium)
What are thebesian veins?
Smallest cardiac veins
The small valveless veins in the walls of the 4 heart chambers that are responsible for venous return of 10% of coronary blood supply
Where is the heart found?
In the middle mediastinum
Where are the pulmonary arteries found?
Receive deoxygenated blood from the right ventricle and deliver it to th lungs
They begin as the pulmonary trunk which is separated from the right ventricle by the pulmonary valve
At level T5-T6 the pulmonary trunk splits into the right and left pulmonary arteries. Each of these then split into 2 and supply blood to the right and left lung respectively
Right pulmonary artery is thicker and longer than left
Where are pulmonary veins found and what are their function?
They receive oxygenated blood from the lungs and deliver it to th left side of the heart to be pumped around the body
There are 4 with one superior and one inferior for each lung
They enter the pericardium to drain into the superior left atrium on the posterior surface
Superior pulmonary veins return blood from upper lobes of lung and inferior veins from lower lobes
What is the oblique sinus?
an inverted J-shaped reflection of the venae cavae and pulmonary veins
It lies behind the atria and in between left and right pulmonary veins.
What is the transverse sinus?
the tunnel-shaped passage posterior to the aorta and pulmonary trunk and anterior to the superior vena cava
What is the superior sinus?
anterior to the ascending aorta and the pulmonary trunk
What are the 3 pericardial sinuses?
Impressions in the pericardial sac
?Superior, oblique and transverse
Where does the apex of the heart point to?
Anterior-inferior direction
What are the sulci of the heart?
The grooves on the surface of the heart formed by the chambers of the heart
Coronary sulcus (runs transversely around the heart and represents the wall dividing the atria from the ventricles)
Anterior and posterior interventricular sulci (runs vertically on their respective sides of the heart and represent the interventricular septum)
Where does the right atrium recieve its deoxygenated blood fron?
Superior and inferior vena cava and coronary veins
What are the 2 parts of the interior surface of the right atrium?
Sinus venarum
Atrium proper
What separates the sinus venarum and atrium proper?
Crista terminalis (muscular ridge)
Where is the sinus venarum? Where does it receive blood from? Where is it embryologically derived from?
located posterior to the crista terminalis. This part receives blood from the superior and inferior vena cavae. It has smooth walls and is derived from the embryonic sinus venosus.
Where is the atrium proper? Where does it receive blood from? Where is it embryologically derived from?
located anterior to the crista terminalis, and includes the right auricle. It is derived from the primitive atrium, and has rough, muscular walls formed by pectinate muscles.
What is the fossa ovalis?
The small oval-shaped depression in the septal wall in the right atrium that is the remnant of the foreamen oval in the foetal heart
Where does the left atrium recieve blood from?
The 4 pulmonary veins
What is the left auricle?
Aka the left atrial appendage
A flag of heart wall on the anterior surface of the left atrium of the heart. It’s a small, conical-shaped chamber that collects blood from the veins and directs it to the ventricles
It increases the capacity of the atrium