Definitions; Conducting system of Heart; Cardiac Muscle Tissue; Cardiac Cycles Flashcards
Chest Pain
Angina pectoris
heart attack due to a lack of blood supply to the myocardium; may lead to cardiac muscle death, blockage of coronary artery
Myocardial infarction(disruption of blood)
abnormal heart sound cause by faulty valve
Heart murmur- can be congenital or acquired
enlargement of the heart
cardiomegaly
narrowing of arteries due to plaque deposits- increases peripheral resistance; plaque deposits happen under the lining of the vesicles
atherosclerosis
inflammation of the pericardium cause by virus or bacteria
pericarditis
high heart rate/ heart is beating abnormally high
tachycardia
low heart rate
bradycardia
abnormal heart rhythm; more than one SA node
arrhythmia
random bursts of electrical activity in the atria, resulting in poorly coordinated contractions; can lead to blood clots and strokes. (Less severe)
atrial fibrillation
rapid, random electrical firing in the ventricles; often leads to cardiac arrest. often leads to cardiac arrest (Very severe)
ventricular fibrillation
pumping efficiency of heart declines and the heart enlarges
Congestive heart failure
specialized cardiac muscle cells, collectively called the blank, spreads impulses through the myocardium
conducting system of the heart
the heartbeat is initiated by a group of specialized cells called the blank near the superior vena cava
sinoatrial (SA) node
The SA node is referred to as the blank, spontaneously depolarizing about 72 beats per minute
pacemaker of the heart
from the SA node, the impulses spread to the blank, and then collect at the blank, in the floor of the blank
walls of the atria; atrioventricular node (av); right atrium
impulses flow from the AV node through the blank, which enters the blank and divides into the right and left blank.
atrioventricular bundle; interventricular septum; bundle branches
the bundle branches conduct impulses to blank, which begin at the blank, and extend up through the blank
perkinje fibers; apex of the heart; walls of the ventricles
blank are short and branched, with 1-2 centrally located nuclei
cardiac muscle cells
blank are joined at the ends, by blank to form cellular networks
Adjacent cardiac muscle cells; intercalated discs
the intercalated discs have two distinct regions; the blank and blank
fascia adherens and gap junctions
the blank help bind adjacent cells together and help transmit contractile force to adjacent cells
the fascia adherens
the blank allow ions to pass between cells, allowing transmission of impulse to spread through network of blank (to help the entire chamber contract at the same time)
gap junctions; cardiac muscle cells
a blank, is the time from start of one heartbeat to the initiation of the next. the contraction of the heart chamber is called blank and the relaxation is called blank
cardiac cycle; systole; diastole
1st step: contraction of the atria initiated by the SA node, causing the ventricles to fill
Atrial Systole
2nd step: atria relax and ventricles begin contracting, causing the AV valves to close (lub)
early ventricular systole
3rd step: continued contraction of the ventricles cause the semilunar valves to open and blood is ejected into the arterial trunks (the atria are still relaxed)
late ventricular systole
4th step: the ventricles begin to relax and the semilunar valves close to prevent blood from back flowing into the ventricles (dub)
early ventricular diastole
5th step: continued relaxation of ventricles causes atrioventricular valves to open and atrial contractions fill ventricles
late ventricular diastole
