Heart Flashcards
1
Q
location of the heart
A
mediastinum, with two-thirds of its mass to the left of the midline.
2
Q
left ventricle forms the
A
apex
3
Q
left atrium forms the
A
base
4
Q
part of the heart between the apex and
right surface and rests mostly on the diaphragm
A
inferior surface
5
Q
deep to the sternum and ribs.
A
anterior surface
6
Q
The membrane that surrounds and protects the heart is the
A
pericardium
7
Q
The pericardium consists of two main parts
A
fibrous pericardium and serous pericardium
8
Q
prevents overstretching of the heart, provides protection, and anchors the heart in the mediastinum; partially fused to the central tendon of the diaphragm and therefore movement of the diaphragm, as in deep breathing, facilitates the movement of blood by the heart
A
fibrous pericardium
9
Q
refers to an emergency procedure for establishing a normal heartbeat and rate of breathing
A
cardiopulmonary resuscitation
10
Q
deeper layer that is thinner, more delicate
mesothelial membrane that forms a double layer around the heart
A
serous pericardium
11
Q
visceral layer of the serous pericardium, which is also called the
A
epicardium
12
Q
Inflammation of the pericardium
A
pericarditis
13
Q
If a great deal of fluid accumulates, this is a life-threatening condition because the fluid compresses the heart, a condition called
A
cardiac tamponade
14
Q
The wall of the heart consists of three layers
A
epicardium, myocardium, and endocardium
15
Q
The epicardium contains
A
blood vessels, lymphatics and nerves that supplies the myocardium
16
Q
layer that is responsible for the pumping action of the heart and is composed of cardiac muscle tissue. It makes up approximately
95% of the heart wall
A
myocardium
17
Q
Inflammation of the myocardium that usually occurs as a complication of a viral infection,
rheumatic fever, or exposure to radiation or certain chemicals or medications.
A
myocarditis
18
Q
refers to an inflammation of the endocardium and typically involves the heart valves
A
endocarditis
19
Q
The smooth endothelial lining minimizes the surface friction as blood passes through the
heart; continuous with the endothelial lining of the large blood vessels attached to the heart.
A
endocardium
20
Q
On the anterior surface of each atrium is a wrinkled pouchlike structure called an
A
auricle
21
Q
Also on the surface of the heart are a series of
grooves that contain coronary blood vessels and a variable amount of fat
A
sulci
22
Q
marks the external boundary between two chambers of the heart
A
sulcus
23
Q
encircles most of the heart and marks the external boundary between the superior atria and inferior ventricles
A
coronary sulcus
24
Q
A shallow groove on the anterior surface of the heart that marks the external boundary between the right and left ventricles on the
anterior aspect of the heart.
A
anterior interventricular sulcus
25
marks the external boundary between the
ventricles on the posterior aspect of the heart
posterior interventricular sulcus
26
forms the right surface of the heart and receives blood from three veins
right atrium
27
RA receives blood from three veins
superior vena cava, inferior vena cava, and coronary sinus
28
RA: The inside of the posterior wall is smooth; the inside of the anterior wall is rough due to the presence of muscular ridges called
pectinate muscles
29
Between the right atrium and left atrium is a thin partition called the
interatrial septum
30
RA: A prominent feature of this septum is an oval depression; the remnant of the foramen ovale, an opening in the interatrial septum of the fetal heart that normally closes soon after birth
Fossa ovalis
31
Blood passes from the right atrium into the right ventricle through a valve that is called the
right atrioventricular valve
32
right atrioventricular valve is also called
tricuspid valve
33
RV: The inside of the right ventricle contains a series of ridges formed by raised bundles of cardiac muscle fibers called
trabeculae carneae
34
RV: The cusps of the right atrioventricular valve are connected to tendon-like cords
chordae tendineae
35
RV: chordae tendineae which in turn are connected to cone-shaped trabeculae carneae called
papillary muscles
36
right ventricle is separated from the left ventricle by a partition called the
interventricular valve
37
Blood passes from the right ventricle through the
pulmonary valve to pulmonary trunk to left and right pulmonary arteries to lungs
38
It receives blood from the lungs through four pulmonary veins
left atrium
39
Blood passes from the left atrium into the left ventricle through the
left atrioventricular valve
40
left atrioventricular valve is also called
bicuspid valve or mitral valve
41
Blood passes from the left ventricle through the
aortic valve to ascending aorta
42
During fetal life, a temporary blood vessel, shunts blood from the pulmonary trunk into the aorta
ductus arteriosus
43
The ductus arteriosus normally closes shortly after birth, leaving a remnant, which connects the aortic arch and pulmonary trunk
ligamentum arteriosum
44
serves as a point of insertion for bundles of cardiac muscle fibers and acts as an electrical insulator between the atria and ventricles.
fibrous skeleton of the heart
45
The aortic and pulmonary valves are known as the
semilunar valves
46
The left side of the heart pumps oxygenated blood into the
systemic circulation
47
the right side of the heart pumps deoxygenated blood into the
pulmonary circulation
48
the myocardium has its own network of blood vessels
coronary circulation
49
branch from the ascending aorta and encircle the heart as a crown encircles the head
coronary arteries
50
When the heart relaxes, however, the
high pressure of blood in the aorta propels blood through the coronary arteries, into capillaries, and then into
coronary veins
51
A narrowing of a heart valve opening that restricts blood flow is known as
stenosis
52
failure of a valve to close completely is termed
insufficiency
53
scar formation or a congenital defect causes
narrowing of the left atrioventricular valve.
mitral stenosis
54
there is backflow of blood from the left ventricle into the left atrium
mitral insufficiency
55
cause of mitral insufficiency
mitral valve prolapse
56
aortic valve is narrowed
aortic stenosis
57
there is backflow of blood from the aorta into the left ventricle
aortic insufficiency
58
artery passes inferior to the left auricle
and divides into the anterior interventricular and circumflex arteries
left coronary artery
59
in the anterior interventricular sulcus and supplies oxygenated blood to the walls of both ventricles.
anterior interventricular artery
60
lies in the coronary sulcus and distributes oxygenated blood to the walls of the left
ventricle and left atrium.
circumflex artery
61
left coronary artery divides into
anterior interventricular and circumflex
arteries
62
follows the posterior interventricular sulcus and supplies the walls of the two ventricles with oxygenated blood.
inferior (posterior) interventricular artery
63
beyond the coronary sulcus runs along the
right margin of the heart and transports oxygenated blood to the wall of the right ventricle
marginal branch
64
connections of two or more arteries
anastomoses
65
alternate route by anastomoses
collateral circulation
66
Most of the deoxygenated blood from the myocardium drains into a large vascular sinus in the coronary sulcus on the posterior surface of the heart, called the
coronary sinus
67
The deoxygenated blood in the coronary sinus empties into the
right atrium
68
The principal tributaries carrying blood into the coronary sinus are the
Great cardiac vein
Middle cardiac vein
Small cardiac vein
Anterior cardiac veins
69
vein in the anterior interventricular sulcus, which drains the areas of the heart supplied by the left coronary artery (left and right ventricles and left atrium)
great cardiac vein
70
vein in the posterior interventricular sulcus, which drains the areas supplied by the inferior interventricular artery of the right coronary artery (left and right ventricles)
Middle cardiac vein
71
vein in the coronary sulcus, which drains
the right atrium and right ventricle
Small cardiac vein
72
veins which drain the right ventricle and open directly into the right atrium
Anterior cardiac veins
73
When blockage of a coronary artery deprives the heart muscle of oxygen, the reestablishment of blood flow, may damage the tissue further
reperfusion
74
antioxidants which remove oxygen free radicals from circulation
vitamin E, vitamin C, beta-carotene, zinc,
and selenium
75
Partial obstruction of blood flow in the coronary arteries may cause a condition of reduced blood flow to the myocardium
myocardial ischemia
76
literally means “strangled chest,” is a severe pain that usually accompanies myocardial ischemia
Angina pectoris
77
ischemic episodes without pain, is particularly dangerous because the person has no forewarning of an impending heart attack.
Silent myocardial ischemia
78
A complete obstruction to blood flow in a coronary artery may result in a condition commonly known as heart attack
myocardial infarction (MI)
79
is the death of an area of tissue because of interrupted blood supply
infarction
80
The ends of cardiac muscle fibers connect to neighboring fibers by irregular transverse thickenings of the sarcolemma called
intercalated discs
81
The discs contain ____ which hold the fibers together
desmosomes
82
low muscle action potentials to conduct from one muscle fiber to its neighbors; allow the entire myocardium of the atria or the ventricles to contract as a single, coordinated unit.
gap junctions
83
The source of this electrical activity is a network of specialized cardiac muscle fibers
(cells) called
autorhythmic fibers
84
autorhythmic fibers have 2 functions
act as a natural pacemaker
form the cardiac conduction system
85
Cardiac excitation normally begins in the
sinoatrial node (SA)
86
The spontaneous depolarization is a
pacemaker potential
87
By conducting along atrial muscle fibers, the action potential reaches the
atrioventricular (AV) node
88
located in the interatrial septum, just anterior to the opening of the coronary sinus
atrioventricular (AV) node
89
From the AV node, the action potential enters the
atrioventricular (AV) bundle (also known as the bundle of His)
90
This bundle is the only site where action potentials can conduct from the atria to the
ventricles
bundle of his
91
After propagating through the AV bundle, the action potential enters both the
right and left bundle branches
92
rapidly conduct the action potential beginning at the apex of the heart upward to the remainder of the ventricular myocardium. Then the ventricles contract, pushing the blood upward toward the semilunar valves.
subendocardial conducting network or Purkinje fibers
93
it is the natural pacemaker
SA node
94
a device that sends out small electrical currents to stimulate the heart to contract.
artificial pacemaker
95
Inflow of Na+ down the electrochemical
gradient, through the voltage-gated fast Na+
channels, produces a
rapid depolarization
96
system that ensures that the chambers of the heart contract in a coordinated manner
conduction system
97
period that prevents tetanus in cardiac muscle fibers
long refractory period
98
The next phase of an action potential in a contractile fiber is a period of maintained depolarization due in part to opening of voltage gated slow Ca2+ channels in the sarcolemma.
plateau
99
The recovery of the resting membrane
potential
repolarization
100
repolarization is due to
outflow of potassium ions and closing of Ca channels
101
increases contraction force by enhancing Ca2+ flow into the cytosol.
epinephrine
102
is the time interval during which a second contraction cannot be triggered
refractory period
103
indicated by the presence in blood of creatine kinase (CK), the enzyme that catalyzes transfer of a phosphate group from creatine phosphate to ADP to make ATP
Myocardial infarction
104
a recording of these electrical signals.
electrocardiogram
105
The instrument used to record the changes
electrocardiograph
106
three clearly recognizable waves appear with each heartbeat
P wave
QRS complex
T wave
107
is a small upward deflection on the ECG; represents atrial depolarization, which spreads from the SA node through contractile fibers in both atria
P wave
108
begins as a downward deflection, continues as a large, upright, triangular wave, and ends as a downward wave; represents rapid ventricular depolarization, as the action potential spreads through ventricular contractile fibers.
QRS complex
109
third wave is a dome-shaped upward deflection; indicates ventricular repolarization and occurs just as the ventricles are starting to relax
T wave
110
Larger P waves indicate
enlargement of an atrium
111
enlarged Q wave may indicate
myocardial infarction
112
enlarged R wave generally indicates
enlarged ventricles.
113
The T wave is flatter than normal when the heart muscle
is receiving insufficient oxygen—as, for example, in coronary artery disease.
114
The T wave may be elevated in
hyperkalemia
115
is the time required for the action potential to travel through the atria, atrioventricular node, and the remaining fibers of the conduction system.
P–Q interval
116
represents the time when the ventricular contractile fibers are depolarized during
the plateau phase of the action potential
S–T segment
117
It is the time from the beginning of ventricular depolarization to the end of ventricular repolarization
Q–T interval
118
Abnormal heart rhythms and inadequate blood flow to the heart may occur only briefly or unpredictably. It is detected by
continuous ambulatory electrocardiography
119
phase of contraction
systole
120
phase of relaxation
diastole
121
heart rate
75/ min
122
includes all of the events associated with
one heartbeat; consists of systole and diastole of the atria plus systole and diastole of the ventricles
cardiac cycle
123
causes contraction and _____ causes relaxation of cardiac muscle fibers.
Depolarization; repolarization
124
the act of listening to sounds within the body, is usually done with a stethoscope
auscultation
125
is an abnormal sound consisting of a clicking, rushing, or gurgling noise that either is heard before, between, or after the normal heart sounds, or may mask the normal heart sounds
heart murmurs
126
caused by blood turbulence associated with closure of the AV valves soon after ventricular systole begins
S1
127
caused by blood turbulence associated with closure of the SL valves at the beginning of ventricular diastole.
S2
128
is the volume of blood ejected from the left ventricle (or the right ventricle) into the aorta (or pulmonary trunk) each minute.
cardiac output
129
Cardiac output equals the
stroke volume and heart rate
130
average cardiac output is
5250 mL/min
131
difference between a person’s maximum cardiac output and cardiac output at rest
Cardiac reserve
132
Three factors regulate stroke volume and ensure that the left and right ventricles pump equal volumes of blood
preload
contractility
afterload
133
Nervous system regulation of the heart originates in the cardiovascular (CV) center
medulla oblongota
134
During strenuous activity, a well-trained athlete can achieve a cardiac output double that of a sedentary person, in part because training causes hypertrophy (enlargement) of the heart. This condition is referred to as
physiological cardiomegaly
135
is the replacement of a severely damaged heart with a normal heart from a brain-dead
or recently deceased donor.
cardiac (heart) transplant
136
The heart begins its development from a group of mesodermal cells called
cardiogenic mesenchyme
137
from the effects of the accumulation of atherosclerotic plaques in coronary arteries, which leads to a reduction in blood flow to the myocardium.
coronary artery disease
138
Thickening of the walls of arteries and loss of elasticity are the main characteristics of a group of diseases called
arteriosclerosis
139
a progressive disease characterized by the formation in the walls of large and medium- sized arteries of lesions called atherosclerotic plaques
atherosclerosis
140
abnormal rhythm as a result
of a defect in the conduction system of the heart
arrhythmias
141
