Heart Flashcards
The external boundary between the atria and ventricles is the
coronary sulcus
EKG to their descriptions: indicates ventricular repolarization
T wave
EKG to their descriptions: represents the time from the beginning of ventricular depolarization to the end of ventricular repolarization
Q-T interval
EKG to their descriptions: represents atrial depolarization
P wave
EKG to their descriptions: represents the time when the ventricular contractile fibers are fully depolarized; occurs during the plateau phase of the action potential
S-T segment
EKG to their descriptions:represents the onset of ventricular depolarization
QRS complex
EKG to their descriptions:represents the conduction time from the beginning of atrial excitation to the beginning of ventricular excitation
P-Q interval
major branch from the ascending aorta; passes inferior to the left auricle
left coronary artery
lies in the posterior interventricular sulcus; supplies the walls of the ventricles with oxygenated blood
posterior interventricular branch
located in the coronary sulcus on the posterior surface of the heart; receives most of the deoxygenated blood from the myocardium
coronary sinus
lies in the coronary sulcus; supplies oxygenated blood to the walls of the right ventricle
marginal branch
lies in the coronary sulcus; drains the right atrium and right ventricle
small cardiac vein
major branch from the ascending aorta; lies inferior to the right auricle
right coronary artery
lies in the posterior interventricular sulcus; drains the right and left ventricles
middle cardiac vein
lies in the anterior interventricular sulcus; supplies oxygenated blood to the walls of both ventricles
anterior interventricular branch (left anterior descending artery
lies in the anterior interventricular sulcus; drains the walls of both ventricles and the left atrium
great cardiac vein
lies in the coronary sulcus; supplies oxygenated blood to the walls of the left ventricle and left atrium
circumflex branch
drain the right ventricle and open directly into the right atrium
anterior cardiac veins
collects oxygenated blood from the pulmonary circulation
left atrium
pumps deoxygenated blood to the lungs for oxygenation
right ventricle
their contraction pulls on and tightens the chordae tendineae, preventing the valve cusps from everting
papillary muscles
cardiac muscle tissue
myocardium
increase blood-holding capacity of the atria
auricles
tendonlike cords connected to the atrioventricular valve cusps which, along with the papillary muscles, prevent valve eversion
chordae tendineae
the superficial dense irregular connective tissue covering of the heart
fibrous pericardium
outer layer of the serous pericardium; is fused to the fibrous pericardium
parietal pericardium
endothelial cells lining the interior of the heart; are continuous with the endothelium of the blood vessels
endocardium
pumps oxygenated blood to all body cells, except the air sacs of the lungs
left ventricle
prevents backflow of blood from the right ventricle into the right atrium
tricuspid valve
collects deoxygenated blood from the systemic circulation
right atrium
left atrioventricular valve
bicuspid valve
the remnant of the foramen ovale, an opening in the interatrial septum of the fetal heart
fossa ovalis
blood vessels that pierce the heart muscle and supply blood to the cardiac muscle fibers
coronary circulation
grooves on the surface of the heart which delineate the external boundaries between the chambers
sulci
prevent backflow of blood from the arteries into the ventricles
semilunar valves
internal wall dividing the chambers of the heart
septum
separate the upper and lower heart chambers, preventing backflow of blood from the ventricles back into the atria
atrioventriclular valves
inner visceral layer of the pericardium; adheres tightly to the surface of the heart
epicardum
amount of blood contained in the ventricles at the end of ventricular relaxation
end-diastolic volume
period of time when cardiac muscle fibers are contracting and exerting force but not shortening
isovolumetric contraction
amount of blood ejected per beat by each ventricle
stroke volume
amount of blood remaining in the ventricles following ventricular contraction
end-systolic volume
difference between a person’s maximum cardiac output and cardiac output at rest
cardiac reserve
period of time when semilunar valves are open and blood flows out of the ventricles
ventricular ejection
period when all four valves are closed and ventricular blood volume does not change
isovolumetric relaxation
This law of the heart equalizes the output of the right and left ventricles and keeps the same volume of blood flowing to both systemic and pulmonary circuits
STARLING LAW OF THE HEART
this term refers to the pressure that must be overcome before semilunar valves can open
afterload
