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31 Cards in this Set
- Front
- Back
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the heart's location....
How much does it weigh? |
between the lungs and rests on the diaphragm.
approx. 300g (10.6oz) |
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Layers of the heart...
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Endocardium
Myocardium Epicardium � |
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Which layer supplies the pumping action?
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myocardium
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Diastole is
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the period of ventricular filling and relaxation
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Systole is
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ventricular contraction resulting in ejection of blood from the ventricles into the pulmonary arteries and aorta.
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During the relaxation phase, all four chambers relax simultaneously
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True
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What are the two atrioventricular valves?
They separate the ____ from the ______ |
tricuspid and mitral valves.
atrium from the ventricle. |
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The semilunar valves are closed during ______
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diastole.
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The heart extracts ____ to ___ of the oxygen delivered.
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70 to 80%
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The cardiac conduction system
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generates and transmits electrical impulses that stimulate the contraction of the myocardium.
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Automaticity
Excitability Conductivity |
Initiate electrical response
respond to electrical response transmit an electrical response. |
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SA node
AV node |
primary pacemaker of the heart
secondary pacemaker of the heart. |
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SA node inherent rate in the heart
AV Ventricular |
60-100
40-60 30 to 40 |
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5 phases
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0- rapid depolarization
1- rapid repolarization, 2- plateau. calcium ions enter 3- final repolarization (completion) 4- resting phase before next depolarization |
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Stroke volume�
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amount of blood ejected with each heartbeat
� |
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Cardiac output�
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amount of blood pumped by ventricle in liters per minute
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Preload�
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degree of stretch of cardiac muscle fibers at end of diastole
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Contractility�
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ability of cardiac muscle to shorten in response to electrical impulse
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After load�
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resistance to ejection of blood from ventricle
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Ejection fraction�
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percent of end diastolic volume ejected with each heart beat
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Cardiac Stroke Volume equals
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stroke volume x heart rate
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What is responsible for the control of heart rate?
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Autonomic nervous system, baroreceptors
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What is responsible for control of stroke volume?
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Preload: Frank-Starling Law
After load: affected by systemic vascular resistance, pulmonary vascular resistance Contractility increased by catecholamines, SNS, some medications � |
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Common clinical manifestations of cardiac issues
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Chest pain
Dyspnea Peripheral edema, weight gain Fatigue Dizziness, syncope, changes in level of consciousness |
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Acute coronary syndrome
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rupture of an atheromatous plaque in a diseased coronary artery, which rapidly forms and obstructive thrombus.
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Normal cholesterol
LDL HDL Triglycerides |
less than 200
less than 160 HDL men 35-70 women 35-85 100-200 |
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Brain (B type) nautriuretic peptide (BNP)
Secreted from? |
neurohormone that helps regulate BP and fluid volume.
The ventricles in response to increased preload. |
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What is a ECG
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a graphic representation of the electrical currents of the heart.
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Echocardiography
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is noninvasive ultrasound test that is used to measure the eject fraction and examine the size shape and motion of cardiac function
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Central Venous Pressure monitoring
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a measurement of the pressure in the vena cava or right atrium.
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Dysrhythmias
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Disorders of formation or conduction (or both) of electrical impulses within heart
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