Heart Flashcards
What are the big picture ideas of the heart?
Location Pericardium External Structure Circulation Internal Structure Coronary Circulation Conduction
Describe the location of the heart
Superiorly - the heart is suspended in the rib cage by the great vessels
Anteriorly - body of the sternum and the thymus
Anterolateral/lateral/posterolateral - lungs and its pleura
Posteriorly - right and left lung/esophagus/aorta
Inferiorly - inferior vena cava penetrates diaphragm on the right side - diaphragmatic portion of parietal pericardium/pericardial sac is fused with central tendon of the diaphragm
Describe what is superior to the heart
The heart is suspended in the rib cage by the great vessels
Describe what is anterior to the heart
The body of the sternum and the thymus
Describe what is anterolateral/lateral/posterolateral to the heart
Lungs and its pleura
Describe what is posterior to the heart
Parts of the lungs
Esophagus
Aorta
Describe what is inferior to the heart and their relationship
Diaphragm - pericardial sac is firmly fused to the central tendon of the diaphragm
What structure of the heart pierces the diaphragm?
Inferior vena cava
What structure encloses the heart and the proximal portion of the great vessels, originating and terminating in the heart, consisting of a parietal and visceral component?
Pericardium
Define and describe the pericardium
Originating and terminating in the heart, the pericardium encloses the heart and the proximal portions of the great vessels - consists of both a parietal and a visceral component
Describe the parietal pericardium
Fibrous pericardium with a serous lining
Describe the visceral pericardium
Inner layer of serous pericardium that covers the origins and terminations of great vessels and the heart
What is another term for visceral pericardium
Epicardium
Describe the pericardial cavity
Between the parietal and the visceral pericardium - surfaces are in contact but are covered in a watery fluid to reduce friction during contractions
What are the external structures of the heart?
Base Apex Coronary Sulcus Anterior and Posterior Interventricular Sulci Auricle Cardiac Fat
Describe the base of the heart
Top of the heart - heart is suspected at its base by the great vessels
Describe the apex of the heart
The apex is the area at which the heart comes to a point at the bottom - points anteriorly, inferiorly, and towards the left
Describe the coronary sulcus of the heart
Groove in the heart separating the ventricles
Describe the anterior and posterior interventricular sulci of the heart
Groove on the anterior and posterior of the heart that divide the right and left ventricles - meeting at the notch near the apex
Describe the auricle of the heart
An appendage of the atrium - strong muscles that help empty the atrium
Describe cardiac fat
Varying amounts of fat the occupy the sulci of the heart
In relation to the chambers of the heart, which is mostly posterior?
Left atrium
In relation to the chambers of the heart, which sits most anteriorly, occupying most of the sternocostal surface?
Right ventricle
In regards to basic circulation by the heart, what are the primary divisions?
Systemic circulation
Pulmonary Circulation
What are the internal structures of the heart?
Left and Right Atria
Left and Right Ventricles
What are the main functions of atria of the heart?
Receive blood
What are the main functions of the ventricles of the heart?
Pump blood to body and lungs
What is the sequence of blood flow in the heart?
Right atrium to right ventricle to the lungs for oxygenation back to the left atrium to the left ventricle to pump to the body
What are the parts of the right atrium of the heart?
Principal cavity
Auricle
Which vessels empty blood into the right atrium of the heart?
Anterior cardiac veins Superior vena cava Inferior vena cava Coronary sinus Thebesian veins (venarum minimarum)
How many vessels empty blood into the right atrium of the heart?
5
Of the vessels that empty blood into the right atrium of the heart, how many are myocardial?
3 myocardial vessels
- coronary sinus
- anterior cardiac veins
- Thebesian veins
Of the vessels that empty blood into the right atrium of the heart, which are not myocardial vessels?
Superior vena cava
Inferior vena cava
Which structure of the heart separates the right atrium from the left atrium?
Interatrial septum
Describe the fossa ovalis of the heart
The remains of the aperture of the foramen ovale in the interatrial septum through which blood flows from the right atrium to the left atrium before birth
Describe the foramen ovale of the heart
The foramen of the heart through which blood flows from the right to the left atrium in the fetus before birth (since blood does not go to the lungs to get oxygenated in the fetus)
What is the limbus of the fossa ovalis of the heart?
A raised margin of the fossa located above and anteriorly to the fossa
What is the purpose of the limbus of the fossa ovalis?
Directs blood flow
What are the valves associated with the right atrium of the heart?
Valve of the inferior vena cava
Valve of the coronary sinus
Tricuspid Valve
Describe the valve of the inferior vena cava of the right atrium of the heart
Falciform fold (much larger in fetus) directs blood from inferior vena cava directly through foramen ovale into atrium in fetal life
Describe the valve of the coronary sinus of the right atrium of the heart
A small fold - incompetent in preventing back-flow into coronary sinus
Describe the tricuspid valve of the right atrium of the heart
Guards the right atrioventricular ostium
Describe the crista terminal is of the right atrium of the heart
Muscular ridge extends downward from near the ostium of the superior vena cava towards the front of the inferior vena cava (smooth from pectinate)
Describe the pectinate muscles of the right atrium of the heart
Muscular ridges within the right auricle of the right atrium of the heart
Describe the right auricle of the right atrium of the heart
Blind ear-shaped pouch extending anteroinferiorly from the heart
What is the function of right ventricle of the heart?
Pumps blood from the heart to the lungs for oxygenation of the blood
How do the walls of the right ventricle differ from the walls of the left ventricle of the heart and why?
Walls of the right ventricle are generally about a 1/3 of the thickness of the walls of the left ventricle because the right ventricle pumps blood only to the lungs
Describe the conus arteriosus of the right ventricle of the heart
Funnel-shaped upper end of right ventricle which gives rise to pulmonary trunk
Describe the chordae tendineae of the right ventricle of the heart
Fibrous cords extending from the cusps of the tricuspid valve to the ends of the papillary muscles
Describe the trabeculae carneae of the right ventricle of the heart
Ridge-like bundles of muscles which project into the cavity of the ventricle - a particularly prominent muscle of this group is the moderator band - contains the right crus of the AV bundle
What is the other term for the moderator band of the right ventricle of the heart?
Septomarginal trabecula
What are the valves associated with the left ventricle of the heart?
Tricuspid valve Pulmonary valve (semilunar)
Describe the pulmonary valve of the right ventricle of the heart
Lies anterior to the aortic valve and consists of a semilunar valve
What is the function of the left atrium of the heart?
Receive oxygenated blood from the lungs
How does the left atrium compare in size to the right atrium?
The left atrium is smaller than the right atrium
What are the vessels that empty into the left atrium of the heart?
4 pulmonary veins
What are the structures of the left atrium of the heart?
Interatrial septum
Left auricle
What is the function of the left ventricle?
Pump oxygenated blood to the body
True or false: The apex of the left ventricle is also the apex of the heart
True
What are the structures of the left ventricle?
Chordae tendineae
Papillary muscles
Trabeculae carneae
Interventricular septum
What are the valves associated with the left ventricle?
Bicuspid/mitral valve
Aortic valve
Describe the bicuspid/mitral valve of the left ventricle of the heart
Guards the left AV ostium (large opening from left atrium to left ventricle)
How many cusps does the mitral valve of the left ventricle have?
2 cusps - bicuspid
Describe the aortic valve of the left ventricle of the heart
Located behind the pulmonary valve
Composed of 3 cusps
Prevents regurgitation of blood into the ventricle while pressure in aorta is high
Of the valves of the heart, which wears out most frequently?
Mitral valve of the left ventricle - creates regurgitation of blood back into left atrium
Viewed from above the heart (having removed atria and arteries), which valve is most anterior?
Pulmonary valve
Viewed from above the heart (having removed atria and arteries), which valve is most in the “middle”?
Aortic valve
Viewed from above the heart (having removed atria and arteries), which valve is on the left?
Bicuspid valve
Viewed from above the heart (having removed atria and arteries), which valve is on the right?
Tricuspid Valve
Describe stenosis and calcium deposits in terms of the heart
Stenosis describes hardening of the valves after calcium deposits within the valves
What happens to the heart in response to stenosis of the valves?
Growth of the heart muscle occurs in response to stenosis of the valves - myocardium can be anywhere from 1/4”-1/2” thick but with stenosis can enlarge to approx an 1” thick
Describe myocardial infarction
Obstruction of a coronary artery that leads to anoxia of the heart area supplied, resulting in a heart attack
True or false: Coronary arteries and cardiac veins are quite variable in origin, course, and termination
True