Chapter 1 Flashcards
The apex of the heart is formed by the
Tip of the left ventricle
The left atrium receives blood from the
Pulmonary veins
True or false
Stimulation of the beta adrenergic receptor cells sites will result in peripheral vasocontriction
False
Blood pressure is the result of cardiac output and peripheral vascular resistance
True or falso
True
The anterior surface of the heart consists primarily of the _____.
right ventricle
Blood pressure is determined by _____ multiplied by _____.
cardiac output; peripheral vascular resistance
The right atrium receives venous blood from the head, neck, and thorax via the _____, from the remainder of the body via the _____, and from the heart via the _____.
uperior vena cava; inferior vena cava; coronary sinus
The heart is divided into _____ chambers but functions as a _____-sided pump.
four; two
Stimulation of alpha-adrenergic receptors results in _____.
peripheral vasoconstriction
Which side of the heart is a low-pressure system that pumps venous blood to the lungs?
Right
Which side of the heart is a high-pressure system that pumps arterial blood to the systemic circulation?
Left
The thick, muscular middle layer of the heart wall that contains the atrial and ventricular muscle fibers necessary for contraction is the _____.
myocardium
Blood flows from the right atrium through the _____ valve into the right ventricle.
tricuspid
Rapid ejection of blood from the ventricular chambers of the heart occurs because the _____ and _____ valves open.
pulmonic; aortic
The base of the heart is found at approximately the level of the _____ rib(s).
second
Which of the following are semilunar valves?
Aortic and pulmonic
Blood leaves the left ventricle through the _____ valve to the aorta and its branches and is distributed throughout the body.
aortic
Blood flows from the left atrium through the _____ valve into the left ventricle.
mitral
The right ventricle expels blood through the _____ valve into the pulmonary trunk.
pulmonic
The primary neurotransmitters of the sympathetic division of the autonomic nervous system are _____.
norepinephrine and epinephrine
Complete occlusion of the _____ coronary artery, also referred to as the widow maker, usually results in sudden death.
left main
Stimulation of beta2 receptor sites results in _____.
relaxation of bronchial smooth muscle
Chronotropy refers to an effect on _____.
heart rate
The left main coronary artery divides into the _____ branches.
anterior descending and circumflex
The primary neurotransmitter of the parasympathetic division of the autonomic nervous system is _____.
acetylcholine
The _____ artery supplies the right atrium and ventricle with blood.
right coronary
The tricuspid valve is _____.
located between the right atrium and right ventricle
When the left ventricle contracts, freshly oxygenated blood flows through the _____ valve into the _____.
aortic; aorta
Thin strands of fibrous connective tissue extend from the atrioventricular (AV) valves to the papillary muscles and prevent the AV valves from bulging back into the atria during ventricular systole. These strands are called _____.
chordae tendineae
__________ is the period during which a heart chamber is contracting and blood is being ejected.
Systole
he thick, muscular middle layer of the heart wall that contains the atrial and ventricular muscle fibers necessary for contraction is the __________.
myocardium
The _____ are the heart chambers that receive blood.
atria
The inferior surface of the heart is also called the _____ surface.
diaphragmatic
The _____ are the heart chambers that pump blood.
ventricles
_____ is the period of relaxation during which a heart chamber is filling.
Diastole
The right atrium receives deoxygenated blood from the _____ _____ _____ (which carries blood from the head and upper extremities), the _____ _____ _____ (which carries blood from the lower body), and the _____ _____ (which receives blood from the intracardiac circulation).
superior vena cava;
inferior vena cava;
coronary sinus
_____ in myocardial cells function as electrical connections and allow the cells to conduct electrical impulses very rapidly.
Gap junction
Typically results when the heart’s demand for oxygen exceeds its supply from the coronary circulation
Myocardial ischemia
Specialized nerve tissue located in the internal carotid arteries and the aortic arch that detect changes in blood pressure
Baroreceptors
The _____ septum separates the right and left atria.
Interatrial
Electrolyte very important in cardiac muscle contraction.
Calcium
A negative _____ effect refers to a decrease in heart rate.
Chronotropic
Space between the lungs that contains the heart, great vessels, trachea, and esophagus, among other structures
Mediastinum
Pulmonary arteries and veins, aorta, superior and inferior vena cavae
Great vessels
Term used to refer to distinct conditions caused by a similar sequence of pathologic events—a temporary or permanent blockage of a coronary artery
Acute coronary syndromes
Amount of blood flowing into the right atrium each minute from the systemic circulation
Venous return
Sensors in the internal carotid arteries and aortic arch that detect changes in the concentration of hydrogen ions (pH), oxygen, and carbon dioxide in the blood
Chemoreceptors
A buildup of excess blood or fluid in the pericardial space can cause cardiac _____.
Tamponade
List two factors that may affect the heart’s efficiency as a pump.
Abnormalities of cardiac muscle, the valves, or the conduction system.
Name the valve that separates the right ventricle from the right atrium.
Tricuspid valve
Define systole.
Contraction or the ejection of blood from a chamber of the heart
What is meant by the term ejection fraction?
Ejection fraction is the percentage of blood pumped out of a heart chamber with each contraction. Each ventricle holds about 150 mL when it is full; they normally eject only about half this volume (70 to 80 mL) with each contraction.
Explain the Frank-Starling law of the heart.
According to the Frank-Starling law of the heart, to a point, the greater the volume of blood in the heart during diastole, the more forceful the cardiac contraction, and the more blood the ventricle will pump (stroke volume). This is important so that the heart can adjust its pumping capacity in response to changes in venous return, such as during exercise. If, however, the ventricle is stretched beyond its physiologic limit, cardiac output may fall because of volume overload and overstretching of the muscle fibers.
A patient has a heart rate of 80 beats/min. His stroke volume is 70 mL/beat. Is his cardiac output normal, decreased, or increased?
Output is normal.
Stroke volume = 70 mL/beat
Heart rate = 80 beats/minute
SV × HR = CO
70 mL/beat × 80 beats/min = 5600 mL/min = 5.6 L/min
Cardiac output = normal (normal is between 4 and 8 L/min)
Briefly describe parasympathetic innervation of the heart.
Parasympathetic (inhibitory) nerve fibers supply the sinoatrial node, atrial muscle, and the atrioventricular junction of the heart by the vagus nerves.
The right atrium receives blood low in oxygen from three vessels. Name them.
Superior vena cava, inferior vena cava, and coronary sinus
List three types of sympathetic (adrenergic) receptor sites.
There are five main types of sympathetic (adrenergic) receptors:
alpha1, alpha2, beta1, beta2, and dopamine (or dopaminergic).
What factors affect afterload?
Afterload is the pressure or resistance against which the ventricles must pump to eject blood. Afterload is influenced by the following: arterial blood pressure, the ability of the arteries to become stretched (arterial distensibility), and arterial resistance.
Define atrial kick.
At the end of ventricular diastole, both atria simultaneously contract to eject 10% to 30% more blood into the ventricles.
What effects can be expected from sympathetic stimulation of the heart?
Sympathetic stimulation of the heart results in increased heart rate, force of contraction, conduction velocity, blood pressure, and cardiac output.
Describe the function of the right atrium of the heart.
The right atrium receives deoxygenated blood from the superior vena cava (which carries blood from the head and upper extremities), the inferior vena cava (which carries blood from the lower body), and the coronary sinus (which receives blood from the intracardiac circulation). Blood passes through the tricuspid valve to the right ventricle.
List six of the signs and symptoms of decreased cardiac output.
Acute changes in blood pressure; acute changes in mental status; cold, clammy skin; color changes in the skin and mucous membranes; crackles (rales); dyspnea; dysrhythmias; fatigue; orthopnea; restlessness
What effects can be expected from parasympathetic stimulation of the heart?
Parasympathetic stimulation has the following actions: it slows the rate of discharge of the SA node, slows conduction through the AV node, decreases the strength of atrial contraction, and can cause a small decrease in the force of ventricular contraction.
What factors affect stroke volume?
Stroke volume is determined by the degree of ventricular filling when the heart is relaxed (preload), the pressure against which the ventricle must pump (afterload), and the myocardium’s contractile state (contracting or relaxing).
Your patient is a 62-year-old woman complaining of a “racing heart.” Your examination of the patient reveals a pulse rate of 192 beats/min. Briefly explain why recognition of a rapid heart rate is important when providing patient care.
Increases in heart rate shorten all phases of the cardiac cycle. The most important is that the time the heart spends relaxing is less. If the length of time for ventricular relaxation is shortened, there is less time for them to fill adequately with blood. If the ventricles do not have time to fill, the following occur: the amount of blood sent to the coronary arteries is reduced, the amount of blood pumped out of the ventricles will decrease (cardiac output), and signs of myocardial ischemia may be seen.
Name the two main branches of the left coronary artery.
The left main coronary artery supplies oxygenated blood to its two primary branches: the left anterior descending (LAD; also called the anterior interventricular) artery and the circumflex artery (CX).
