MedSurge: Ch.52 Cardiovascular Problems Flashcards
1
Q
What side of the body is the heart on?
A
Left.
2
Q
How many layers of the heart are there?
A
3
3
Q
What are the three layers of the heart?
A
The epicardium is the outermost layer of the heart.
The myocardium is the middle layer and is the actual contracting muscle of the heart.
The endocardium is the innermost layer and lines the inner chambers and heart valves.
4
Q
What is the Pericardial Sac?
A
Encases and protects the heart from trauma and infection
5
Q
What are the two layers of the pericardial sac?
A
The parietal pericardium is the tough, fibrous outer membrane that attaches anteriorly to the lower half of the sternum, posteriorly to the thoracic vertebrae, and inferiorly to the diaphragm.
The visceral pericardium is the thin, inner layer that closely adheres to the heart.
6
Q
Where is the pericardial sapce?
A
The pericardial space is between the parietal and visceral layers; it holds 5 to 20 mL of pericardial fluid, lubricates the pericardial surfaces, and cushions the heart.
7
Q
How many chambers of the heart are there?
A
4
8
Q
What is the job of the right atria?
A
The right atrium receives deoxygenated blood from the body via the superior and inferior vena cava.
9
Q
What is the job of the right ventricle?
A
The right ventricle receives blood from the right atrium and pumps it to the lungs via the pulmonary artery.
10
Q
What is the job of the left atrium?
A
The left atrium receives oxygenated blood from the lungs via 4 pulmonary veins.
11
Q
What is the job of the left ventricle?
A
The left ventricle is the largest and most muscular chamber; it receives oxygenated blood from the lungs via the left atrium and pumps blood into the systemic circulation via the aorta.
12
Q
What is the 4 valves of the heart?
A
There are 2 atrioventricular valves, the tricuspid and the mitral, which lie between the atria and ventricles.
There are 2 semilunar valves, the pulmonic and the aortic.
13
Q
What is the sinoatrial (SA) node?
A
The main pacemaker that initiates each heartbeat
14
Q
Where is the SA node located?
A
It is located at the junction of the superior vena cava and the right atrium.
15
Q
How much does the SA node generate? What is it controlled by?
A
The SA node generates electrical impulses at 60 to 100 times per minute and is controlled by the sympathetic and parasympathetic nervous systems.
16
Q
What is the AV node?
A
Atrioventricular (AV) node
17
Q
Where is the AV node located?
A
Located in the lower aspect of the atrial septum.
18
Q
What is the job of the AV node?
A
Receives electrical impulses from the SA node.
If the SA node fails, the AV node can initiate and sustain a heart rate of 40 to 60 beats per minute.
19
Q
What is the bundel of his?
A
- A continuation of the AV node; located at the interventricular septum
- It branches into the right bundle branch, which extends down the right side of the interventricular septum; and the left bundle branch, which extends into the left ventricle.
- The right and left bundle branches terminate in the Purkinje fibers.
20
Q
What are the Purkinje fibers?
A
- Purkinje fibers are a diffuse network of conducting strands located beneath the ventricular endocardium.
- These fibers spread the wave of depolarization through the ventricles.
- Purkinje fibers can act as the pacemaker with a rate between 20 and 40 beats per minute when higher pacemakers (such as the SA and AV nodes) fail.
21
Q
! The right main coronary artery does what?
A
The right main coronary artery supplies the right atrium and ventricle, the inferior portion of the left ventricle, the posterior septal wall, and the SA and AV nodes.
22
Q
What does the left main coronary artery consist of?
A
The left main coronary artery consists of 2 major branches, the left anterior descending (LAD) and the circumflex arteries.
23
Q
What does the LAD DO?
A
The LAD artery supplies blood to the anterior wall of the left ventricle, the anterior ventricular septum, and the apex of the left ventricle.
24
Q
What do the circumflex arteries do?
A
The circumflex artery supplies blood to the left atrium and the lateral and posterior surfaces of the left ventricle.
25
What is the main job in a nutshell of the coronary arteries?
They supply blood to the capillaries of the myocardium.
26
If a blockage occurs in the coronary arteries what can happen?
Myocardial infarction (MI).
27
What are the four heart sounds?
1. The first heart sound (S1) is heard as the atrioventricular valves close and is heard loudest at the apex of the heart.
2. The second heart sound (S2) is heard when the semilunar valves close and is heard loudest at the base of the heart.
3. A third heart sound (S3) may be heard if ventricular wall compliance is decreased and structures in the ventricular wall vibrate; this can occur in conditions such as heart failure or valvular regurgitation. However, a third heart sound may be normal in individuals younger than 30 years.
4. A fourth heart sound (S4) may be heard on atrial systole if resistance to ventricular filling is present; this is an abnormal finding, and the causes include cardiac hypertrophy, disease, or injury to the ventricular wall.
28
! The faster the heart rate?
The faster the heart rate, the less time the heart has for filling. At very fast rates the cardiac output decreases.
29
What is the normal sinus heart rate?
The normal sinus heart rate is 60 to 100 beats per minute.
30
What is considered sinus tachycardia?
A heart rate more than 100 beast per min.
31
What is sinus bradycardia?
less than 60 beats per min.
32
What makes up the autonomic nervous system?
Sympathetic and parasympathetic nervous system.
33
What do we get when we stimulate the sympathetic nerve fibers? What does that do?
releases the neurotransmitter norepinephrine, producing an increased heart rate, increased conduction speed through the AV node, increased atrial and ventricular contractility, and peripheral vasoconstriction.
34
When does the body stimulate the sympathetic nerve fibers?
Stimulation occurs when a decrease in pressure is detected.
35
What happens when we stimulate the parasympathetic nerve fibers?
Stimulation of the parasympathetic nerve fibers releases the neurotransmitter acetylcholine, which decreases the heart rate and lessens atrial and ventricular contractility and conductivity. Stimulation occurs when an increase in pressure is detected.
36
What are baroreceptors?
Baroreceptors (specialized nerve endings affected by changes in the arterial BP), also called pressoreceptors, are located in the walls of the aortic arch and carotid sinuses.
37
What stimulates the baroreceptors?
Increases in arterial pressure stimulate baroreceptors, and the heart rate and arterial pressure decrease.
38
What does a decrease in arterial pressure do to the baroreceptors?
Decreases in arterial pressure reduce stimulation of the baroreceptors and vasoconstriction occurs, as does an increase in heart rate.
39
What are the stretch receptors?
Stretch receptors, located in the vena cava and the right atrium, respond to pressure changes that affect circulatory blood volume.
40
What happens when the When the BP decreases as a result of hypovolemia?
A sympathetic response occurs, causing an increased heart rate and blood vessel constriction; when the BP increases as a result of hypervolemia, an opposite effect occurs.
41
What is the generic name of Antidiuretic hormone ?
Vasopressin.
42
How does Antidiuretic hormone (vasopressin) influences BP?
indirectly by regulating vascular volume.
43
Increases in blood volume result in what when it comes to antidiuretic hormone?
Increases in blood volume result in decreased antidiuretic hormone release, increasing diuresis, decreasing blood volume, and thus decreasing BP.
44
What happens to ant-diuretic hormone when blood volume decreases?
Decreases in blood volume result in increased antidiuretic hormone release; this promotes an increase in blood volume and therefore BP.
45
What is renin?
A potent vasoconstrictor, causes the BP to increase.
46
What does renin convert into?
Renin converts angiotensinogen to angiotensin I; angiotensin I is then converted to angiotensin II in the lungs.
Angiotensin II stimulates the release of aldosterone, which promotes water and sodium retention by the kidneys; this action increases blood volume and BP.
47
! What are arteries?
Arteries are vessels through which the blood passes away from the heart to various parts of the body; they convey highly oxygenated blood from the left side of heart to the tissues.
48
! What are arterioles?
Arterioles control the blood flow into the capillaries.
49
! What are capillaries?
Capillaries allow the exchange of fluid and nutrients between the blood and the interstitial spaces.
50
! What are venules?
Venules receive blood from the capillary bed and move blood into the veins.
51
! What is the job of veins?
Veins transport deoxygenated blood from the tissues back to the right heart and then to the lungs for oxygenation.
52
! What is the job of valves?
Valves help return blood to the heart against the force of gravity.
53
! What is the job of the lymphatic system?
The lymphatics drain the tissues and return the tissue fluid to the blood.
54
What is Troponin?
A chemical released by the heart when there is heart damage.
55
What is a normal troponin range?
less than 0.35
56
If your troponin is over 0.35 what does that mean?
There is heart damage.
57
What is CK-MB creatine kinase, myocardial muscle)?
An elevation in value indicates myocardial damage.
b. An elevation occurs within hours and peaks at 18 hours following an acute ischemic attack.
c. Normal value for CK-MB (CK-2) is 2 to 6 ng/mL (2 to 6 mcg/L) for males and 2 to 5 ng/mL (2 to 5 mcg/L) for females.
58
What is myoglobin?
a. Myoglobin is an oxygen-binding protein found in cardiac and skeletal muscle.
b. The level rises within 2 hours after cell death, with a rapid decline in the level after 7 hours; however, it is not cardiac specific.
59
When it comes to the heart what can red blood cell count tell us?
The red blood cell count decreases in rheumatic heart disease and infective endocarditis and increases in conditions characterized by inadequate tissue oxygenation.
60
What is happening with the white blood cell count in regards to the heart?
The white blood cell count increases in infectious and inflammatory diseases of the heart and after MI, because large numbers of white blood cells are needed to dispose of the necrotic tissue resulting from the infarction.
61
When it comes to the heart what does a elevation of hematocrit mean?
An elevated hematocrit level can result from vascular volume depletion.
62
What does a Decreases in hemoglobin and hematocrit levels can indicate?
Anemia.
63
! when can an increase of blood coagulation factors occur? What can this cause?
An increase in coagulation factors can occur during and after MI, which places the client at greater risk for thrombophlebitis and formation of clots in the coronary arteries.
64
What does the lipid profile measure?
Serum cholesterol, triglyceride, and lipoprotein levels.
65
What is the lipid profile used to diagnose?
The lipid profile is used to assess the risk of developing coronary artery disease.
66
What should your LDL be?
less than 30. or you have plaque and clots.
67
Homocysteine?
Elevated levels may increase the risk of cardiovascular disease; normal value is 4.5 to 11.9 mcmol/L (4.5 to 11.9 mcmol/L), age and gender dependent.
68
Highly sensitive C-reactive protein (hsCRP)?
Detects an inflammatory process such as that associated with the development of atherothrombosis; a level less than 1 mg/L is considered low risk, and a level greater than 3 mg/L places the client at high risk for heart disease.
69
Microalbuminuria?
A small amount of protein in the urine has been a marker for endothelial dysfunction in cardiovascular disease.
70
What is hypokalemia affect on the heart?
Hypokalemia causes increased cardiac electrical instability, ventricular dysrhythmias, and increased risk of digoxin toxicity.
71
What does the ECG show for a heart in hypokalemia?
In hypokalemia, the electrocardiogram (ECG) shows flattening and inversion of the T wave, the appearance of a U wave, and ST depression.
72
What kind of dyrythmias does hyperkalemia cause?
Hyperkalemia causes asystole and ventricular dysrhythmias.
73
In hyperkalemia what does the heart look like?
In hyperkalemia, the ECG may show tall, peaked T waves, widened QRS complexes, prolonged PR intervals, or flat P waves.
74
What drug do we use to decrease serum sodium?
The serum sodium level decreases with the use of diuretics.
75
In heart failure what happens?
The serum sodium level decreases in heart failure, indicating water excess.
76
What can hypocalcemia cause?
Ventricular dysrhythmias, prolonged ST and QT intervals, and cardiac arrest.
77
What does hypercalcemia look like on a ecg?
Hypercalcemia can cause a shortened ST segment and widened T wave, atrioventricular block, tachycardia or bradycardia, digitalis hypersensitivity, and cardiac arrest.
78
How should we interpret phosphate levels?
Phosphorus levels should be interpreted with calcium levels, because the kidneys retain or excrete one electrolyte in an inverse relationship to the other.
79
What is the affect of magnesium on the heart?
A low magnesium level can cause ventricular tachycardia and fibrillation.
80
What does the ecg of a hypomagnesium?
Electrocardiographic changes that may be observed with hypomagnesemia include tall T waves and depressed ST segments.
81
What is the affect of hypermagnesium?
A high magnesium level can cause muscle weakness, hypotension, and bradycardia.
82
What does the ecg look like with hyper magnesium?
Electrocardiographic changes that may be observed with hypermagnesemia include a prolonged PR interval and widened QRS complex.
83
! What is the effect of electrolytes and mineral imbalances on the heart?
Electrolyte and mineral imbalances can cause cardiac electrical instability that can result in life-threatening dysrhythmias.
84
Blood urea nitrogen what is it?
The blood urea nitrogen level is elevated in heart disorders such as heart failure and cardiogenic shock that reduce renal circulation.
85
What is the blood glucose level in relation to the heart?
An acute cardiac episode can elevate the blood glucose level.
86
! B-type natriuretic peptide (BNP)?
BNP is released in response to atrial and ventricular stretch; it serves as a marker for heart failure.
87
! What are the normal levels for BNP?
BNP levels should be less than 100 ng/mL (less than 100 mcg/L); the higher the level, the more severe the heart failure.
88
What is a chest x-ray?
Radiography of the chest is done to determine anatomical changes such as the size, silhouette, and position of the heart.
89
What are the interventions for a chest x-ray?
a. Prepare the client, explaining the purpose and procedure.
b. Remove jewelry.
c. Ensure that the client is not pregnant.
90
What is elctrocardiograophy?
This common noninvasive diagnostic test records the electrical activity of the heart and is useful for detecting cardiac dysrhythmias, location and extent of MI, and cardiac hypertrophy, and for evaluation of the effectiveness of cardiac medications.
91
What are the interventions for elctrocardiograophy?
a. Determine the client’s ability to lie still; advise the client to lie still, breathe normally, and refrain from talking during the test.
b. Reassure the client that an electrical shock will not occur.
c. Document any cardiac medications the client is taking.
92
What is a holter monitor?
A noninvasive test; the client wears a monitor and an electrocardiographic tracing is recorded continuously over a period of 24 hours or more while the client performs her or his activities of daily living.
93
What does the holter monitor identify?
The monitor identifies dysrhythmias if they occur and evaluates the effectiveness of antidysrhythmics or pacemaker therapy.
94
! What are the interventions for holter monitoring?
Instruct the client to resume normal daily activities and to maintain a diary documenting activities and any symptoms that may develop for correlation with the electrocardiographic tracing.
Instruct the client using a wired monitor to avoid tub baths, showers, or swimming, because they will interfere with the electrocardiographic recorder device.
95
What is echocardiography?
This noninvasive procedure is based on the principles of ultrasound and evaluates structural and functional changes in the heart.
96
What is echocardiography used for?
Used to detect valvular abnormalities, congenital heart defects, wall motion, ejection fraction, and cardiac function.
97
What is transesophageal echocardiography?
Transesophageal echocardiography may be performed, in which the echocardiogram is done through the esophagus to view the posterior structures of the heart; this is an invasive exam and requires preparation and care similar to endoscopy procedures.
98
What are the interventions for echocardiography?
Advise the client to lie still, breathe normally, and refrain from talking during the test.
99
What is a stress test?
This noninvasive test studies the heart during activity and detects and evaluates coronary artery disease.
b. Treadmill testing is the most commonly used mode of stress testing.
100
What do we do if the client cannot withstand exersize?
If the client is unable to tolerate exercise, an intravenous (IV) infusion of dipyridamole or dobutamine hydrochloride is given to dilate the coronary arteries and simulate the effect of exercise; the client may need to be NPO (nothing by mouth) for 3 to 6 hours preprocedure.
101
What is the pre-procedure for a stress test?
a. Ensure that an informed consent is obtained if required.
b. Encourage adequate rest the night before the procedure.
c. Instruct the client having a noninvasive test to eat a light meal 1 to 2 hours before the procedure.
d. Instruct the client to avoid smoking, alcohol, and caffeine before the procedure.
e. Instruct the client to ask the primary health care provider (PHCP) or cardiologist about taking prescribed medication on the day of the procedure; theophylline products are usually withheld 12 hours before the test, and calcium channel blockers and beta blockers are usually withheld on the day of the test to allow the heart rate to increase during the stress portion of the test.
if. Instruct the client to wear nonconstrictive, comfortable clothing and supportive rubber-soled shoes for the exercise stress test.
g. Instruct the client to notify the PHCP if any chest pain, dizziness, or shortness of breath occurs during the procedure.
102
What is the post-procedure for a stress test?
Instruct the client to avoid taking a hot bath or shower for at least 1 to 2 hours.
103
Myocardial nuclear perfusion imaging (MNPI)?
Nuclear cardiology involves the use of radionuclide techniques and scanning for cardiovascular assessment.
104
What is the most common MNPI?
The most common tests include technetium pyrophosphate scanning, thallium imaging, and multigated cardiac blood pool imaging; these tests can evaluate cardiac motion and calculate the ejection fraction.
105
! What are the preprocedures for a MNPI?
a. Ensure that an informed consent is obtained.
b. Inform the client that a small amount of radioisotope will be injected and that the radiation exposure and risks are minimal.
106
What is the postprocedure for MNPI?
a. Assess vital signs.
b. Assess injection site for bleeding or discomfort.
c. Inform the client that fatigue is possible.
107
Magnetic resonance imaging (MRI)? What information does it tell us?
This is a noninvasive diagnostic test that produces an image of the heart or great vessels through the interaction of magnetic fields, radiowaves, and atomic nuclei.
b. It provides information on chamber size and thickness, valve and ventricular function, and blood flow through the great vessels and coronary arteries.
108
What is the pre-procedure for an MRI?
a. Evaluate the client for the presence of a pacemaker or other implanted items that present a contraindication to the test.
b. Ensure that the client has removed all metallic objects such as a watch, jewelry, clothing with metal fasteners, and metal hair fasteners.
c. Inform the client that she or he may experience claustrophobia while in the scanner.
109
What are Electrophysiological studies?
An invasive procedure in which a programmed electrical stimulation of the heart is induced to cause dysrhythmias and conduction defects; assists in finding an accurate diagnosis and aids in determining treatment.
110
What is a Electron-beam computed tomography (EBCT) scan?
Determines whether calcifications are present in the arteries; a coronary artery calcium (CAC) score is provided (a score higher than 300 indicates high risk of myocardial infarction and requires intensive preventive treatment).
111
What is a cardiac catheterization?
a. An invasive test involving insertion of a catheter into the heart and surrounding vessels
b. Obtains information about the structure and performance of the heart chambers and valves and the coronary circulation
112
! What is the preprocedure for cardiac catheterization?
a. Ensure that informed consent has been obtained.
b. Assess for allergies to seafood, iodine, or radiopaque dyes; if allergic, the client may be premedicated with antihistamines and corticosteroids to prevent a reaction.
c. Withhold solid food for 6 to 8 hours and liquids for 4 hours as prescribed to prevent vomiting and aspiration during the procedure.
d. Document the client’s height and weight, because these data will be needed to determine the amount of dye to be administered.
e. Document baseline vital signs and note the quality and presence of peripheral pulses for postprocedure comparison.
f. Inform the client that a local anesthetic will be administered before catheter insertion.
g. Inform the client that she or he may feel a fluttery feeling as the catheter passes through the heart, a flushed and warm feeling when the dye is injected, a desire to cough, and palpitations caused by heart irritability.
h. The insertion site is prepared by shaving or clipping the hair and cleaning with an antiseptic solution.
i. Administer preprocedure medications such as sedatives if prescribed.
j. Insert an IV line if prescribed.
113
! What is the postprocedure for a cardiac cathertereization?
a. Monitor vital signs and cardiac rhythm for dysrhythmias at least every 30 minutes for 2 hours initially.
b. Assess for chest pain and, if dysrhythmias or chest pain occurs, notify the PHCP.
c. Monitor peripheral pul1111ses and the color, warmth, and sensation of the extremity distal to the insertion site at least every 30 minutes for 2 hours initially.
d. Notify the PHCP if the client reports numbness and tingling; if the extremity becomes cool, pale, or cyanotic; or if loss of the peripheral pulses occurs. This could indicate clot formation and is an emergency.
e. Apply a sandbag or compression device (if prescribed) to the insertion site to provide additional pressure if required.
f. Monitor for bleeding; if bleeding occurs, apply manual pressure immediately and notify the PHCP.
g. Monitor for hematoma; if a hematoma develops, notify the PHCP.
h. Keep the extremity extended for 4 to 6 hours, as prescribed, keeping the leg straight to prevent arterial occlusion.
i. Maintain strict bed rest for 6 to 12 hours, as prescribed; however, the client may turn from side to side. Do not elevate the head of the bed more than 15 degrees.
j. If the antecubital vessel was used, immobilize the arm with an armboard.
k. If the PHCP uses a vascular closure device to seal the arterial puncture site, there is no need for prolonged compression or bed rest, and clients may be out of bed in 1 to 2 hours.
l. Encourage fluid intake, if not contraindicated, to promote renal excretion of the dye and to replace fluid loss caused by the osmotic diuretic effect of the dye.
m. Monitor for nausea, vomiting, rash, or other signs of hypersensitivity to the dye.
114
What is Intravascular ultrasonography (IVUS)?:
A catheter with a transducer is used as an alternative to injecting a dye into the coronary arteries and detects plaque distribution and composition; it also detects arterial dissection and the degree of stenosis of an occluded artery.
