Cardiovascular Anatomy-01 Flashcards
where is the heart located?
in the middle of the mediastinum and surrounded by the pericardium
apex of the heart
tip of the heart formed by the left ventricle and the most inferior surface
base of the heart
broader area of the heart where great vessels arise from
what are some major landmarks of the heart?
SVC, IVC, pulmonary trunk, aorta
structures superior to the heart/in superior mediastinum
aortic arch, esophagus, trachea
structures anterior to the heart/in the anterior mediastinum
thymus gland, sternebrae
structures posterior to the heart/in posterior mediastinum
descending aorta, esophagus, lymph nodes, vagus nerve, thoracic duct
structures in the middle mediastinum
ascending aorta, pulmonary trunk, phrenic nerves
anterior surface features
RV most prominent, RA has an associated auricle to accommodate more blood; LV off to side and tip forms apex, LA + associated auricle tucked in behind heart; SVC & IVC drain deoxygenated blood from body, ascending aorta continues as aortic arch behind heart to become descending thoracic aorta, pulm. trunk delivers de-O2 blood to lungs
posterior surface features
LA most prominent (vessels entering are pulm. veins), left ventricular wall + some of RA slightly visible, SVC/IVC quite indistinguishable from RA
sulci of the heart
grooves where coronary BV sit as protection from heart moves against pericardium, fat pads also provide added protection
coronary sulci
left and right sulci between the atria and ventricles
interventricular (IV) sulci
anterior and posterior sulci occurring between the ventricles
what do coronary arteries do and where are they located?
supply blood to the heart muscle itself; L and R coronary arteries come off the base of the ascending aorta
what does the left coronary artery branch off into?
it bifurcates past the pulm. trunk to become the circumflex artery going through the coronary sulcus and the LAD artery going through the IV sulcus
what does the right coronary artery branch off into?
it starts in the coronary sulcus and curls around the back of the heart to get to the right IV sulcus as the posterior IV artery, and laterally down the right side as the marginal artery
what is the main left coronary vein?
great cardiac vein
what are the right coronary veins?
small, anterior, and middle cardiac veins
what is the coronary sinus?
a dilated vessel on the posterior aspect of the heart that empties blood into the right atrium
which vessels empty into the coronary sinus?
great, small and middle cardiac veins; the anterior cardiac vein dumps blood directly into the RA via a hole
what does the pericardium consist of?
fibrous pericardium (irregular dense CT), parietal pericardium and visceral pericardium (thin epithelia layer secreting serous fluid)
cardiac tamponade
acute compression of the heart due to the accumulation of fluid within the pericardial cavity, excess fluid can be drained with a needle
what are the layers of the heart wall from superficial to deep?
epicardium, myocardium and endocardium
what is the difference b/w the L & R ventricle?
LV: cylindrical/conical shape, heart wall is thick b/c lots of pressure needs to be generated to pump blood to every tissue of the body
RV: half moon shape, has a thinner wall b/c less pressure needs to be generated (only sends blood to the lungs which have little vascular resistance)
inflammation of the heart can occur as:
epicarditis (pericarditis), myocarditis, endocarditis
epicarditis
inflammation of the epicardium (outer lining of the heart) caused by fluid/pus accumulation
myocarditis
caused by viral infection, rheumatic fever, radiation or meds
endocarditis
often bacterial and affects heart valves, fatal if left untreated
path of blood flow in the heart
2 closed circuits. systemic circuit carries oxygenated blood in the left side of the heart and in the arteries, pulmonary circuit carries deoxygenated blood in the right side and in veins to the lungs
what is the function of heart valves?
to ensure blood flows in one direction (can be useful when applying cardiac compressions
AV valves
tricuspid and bicuspid (mitral) valves, have cusps/leaflets; chordae tendinae attach to papillary muscles (sub-valvular apparatus) — provide tension to prevent AV valve prolapse
how do the AV valves open?
When the pressure of the blood in the atria becomes higher than the pressure inside the ventricles
semilunar valves
aortic and pulmonary SL valves, 3 semilunar leaflets and C-shaped cusps that capture the blood to prev. backflow into ventricle, also causes them to close
how do the semilunar valves open?
when the ventricular pressure is higher than the pulmonary trunk and aorta pressure (no sub-valvular apparatus)
fibrous skeleton
made of collagen fibres that become dense around the cusps of valves and form annular rings
what are the 4 functions of the fibrous skeleton?
provide structural foundation for heart valves,
maintains valve diameter (prevents overstretching), attachment site for muscle fibers, electrically separates the atria from the ventricles
how are heart sounds auscultated?
heard at locations that do not correspond to where the valves are located; stethoscope should be placed away from the heart in the direction sound waves travel from a valve when it closes
what is represented by the lub-dub sound?
Lub → AV valves closing
Dub → ventricular relaxation (SL valves go)
where is the aortic SL valve sound heard?
2nd intercostal space (right)
where is the pulmonary SL valve sound heard?
2nd intercostal space (left)
where is the bicuspid valve sound heard?
5th intercostal space (left)
where is the tricuspid valve sound heard?
left lower sternal border (LLSB)
heart valve stenosis
cusps or flaps of heart valve are too stiff and unable to open fully, making it difficult for blood to flow through; narrowing
what valves are affected by stenosis?
aortic (common wear and tear), pulmonic (developmental issues in infants), mitral (most common)
heart valve prolapse
heart valve cusps are insufficient/incompetent, allowing blood to flow backward (regurgitation) through valve when heart chamber contracts; most commonly occurs in mitral valve and is hear as a murmur (“whoosh”)
