Chapter 22: Introduction to the Cardiovascular System

The nurse is caring for a client admitted with angina who is scheduled for cardiac catheterization. The client is anxious and asks the reason for this test. What is the best response?

"Cardiac catheterization is usually done to assess how blocked or open a client's coronary arteries are." Cardiac catheterization is usually used to assess coronary artery patency to determine if revascularization procedures are necessary. A thallium stress test shows myocardial ischemia after stress. An ECG shows the electrical activity of the heart.

A 52-year-old female patient is going through menopause and asks the nurse about estrogen replacement for its cardioprotective benefits. What is the best response by the nurse?

"Current evidence indicates that estrogen replacement is not effective at preventing cardiovascular disease and carries some risks." In the past, hormone therapy was routinely prescribed for postmenopausal women with the belief that it would deter the onset and progression of coronary artery disease (CAD). However, based on results from the multisite, prospective, longitudinal Women's Health Initiative study, the American Heart Association (AHA) no longer recommends the use of hormone therapy to prevent cardiovascular disease. However, hormone replacement therapy has not been shown to be harmful for all women, and it may be a good choice for some women seeking to reduce symptoms of menopause.

The nurse is conducting client teaching about cholesterol levels. When discussing the client's elevated LDL and lowered HDL levels, the client shows an understanding of the significance of these levels by stating what?

"Increased LDL and decreased HDL increase my risk of coronary artery disease." Elevated LDL levels and decreased HDL levels are associated with a greater incidence of coronary artery disease.

The nurse is caring for a client who has a history of heart disease. What factor should the nurse identify as possibly contributing to a decrease in cardiac output?

A heart rate of 54 bpm Cardiac output is computed by multiplying the stroke volume by the heart rate. Cardiac output can be affected by changes in either stroke volume or heart rate, such as a rate of 54 bpm. An increase in preload will lead to an increase in stroke volume. A pulse oximetry reading of 94% does not indicate hypoxemia, as hypoxia can decrease contractility. Transitioning from standing to sitting would more likely increase rather than decrease cardiac output.

A lipid profile has been ordered for a client who has been experiencing cardiac symptoms. When should a lipid profile be drawn in order to maximize the accuracy of results?

After a 12-hour fast Although cholesterol levels remain relatively constant over 24 hours, the blood specimen for the lipid profile should be obtained after a 12-hour fast.

The nurse is caring for a patient who has undergone peripheral arteriography. How should the nurse assess the adequacy of peripheral circulation?

By checking peripheral pulses Peripheral arteriography is used to diagnose occlusive arterial disease in smaller arteries. The nurse observes the patient for bleeding and cardiac dysrhythmias and assesses the adequacy of peripheral circulation by frequently checking the peripheral pulses. Hemodynamic monitoring is used to assess the volume and pressure of blood in the heart and vascular system.

A nurse assessing a client who underwent cardiac catheterization finds the client lying flat on the bed. The client's temperature is 99.8° F (37.7° C). The client's blood pressure is 104/68 mm Hg. The client's pulse rate is 76 beats/minute. The nurse detects weak pulses in the leg distal to the puncture site. Skin on the leg is cool to the touch. The puncture site is dry, but swollen. What is the most appropriate action for the nurse to take?

Contact the health care provider and report the findings. The client is probably developing a hematoma at the puncture site. The decreased pulses, swelling, and cool temperature in the leg are all classic signs that blood flow to that extremity is compromised. The nurse should notify the health care provider immediately to preserve the blood flow in the client's leg. Documenting findings and checking the client again in 1 hour, slowing the I.V. fluid, and encouraging the client to perform isometric leg exercises aren't appropriate actions for the nurse to take at this time.

A patient's gradual decline in activity tolerance and increased shortness of breath have prompted her health care provider to assess the structure and size of her heart. Which of the following diagnostic tests is most likely to yield these assessment data?

Echocardiography An echocardiogram yields a two-dimensional rendering of the heart's structure and mechanical function. An ECG indicates the heart's electrical activity, and angiography and cardiac catheterization are used to assess the patency of the coronary arteries.

The nurse receives a laboratory report indicating the client's magnesium level is 5.2 mEq/L. What symptoms is the client at risk to experience? Select all that apply.

Headache Hypotension Irregular heartbeat The normal serum magnesium level is 1.5-2.5 mEq/L. Hypermagnesemia can cause nausea, headache, hypotension and irregular heartbeat. Hypomagnesemia can cause ventricular and atrial tachycardia.

Following the morning assessment of an older adult patient, the nurse has documented, "Edema 3+ present to ankles and feet; dorsalis pedis and posterior tibial pulses palpable bilaterally." The nurse should recognize that this patient may be exhibiting symptoms of:

Heart failure Peripheral edema is associated with heart failure and peripheral vascular diseases, such as deep vein thrombosis or chronic venous insufficiency. Angina and hypertension do not directly cause peripheral edema. Intermittent claudication is a symptom that represents arterial insufficiency.

A brain (B-type) natriuretic peptide (BNP) sample has been drawn from an older adult client who has been experiencing vital fatigue and shortness of breath. This test will allow the care team to investigate the possibility of what diagnosis?

Heart failure The level of BNP in the blood increases as the ventricular walls expand from increased pressure, making it a helpful diagnostic, monitoring, and prognostic tool in the setting of HF. It is not specific to cardiomyopathy, pleurisy, or valve dysfunction.

The physician has ordered a high-sensitivity C-reactive protein (hs-CRP) drawn on a client. The results of this test will allow the nurse to evaluate the role of what process that is implicated in the development of atherosclerosis?

Inflammation High-sensitivity CRP is a protein produced by the liver in response to systemic inflammation. Inflammation is thought to play a role in the development and progression of atherosclerosis.

In preparation for transesophageal echocardiography (TEE), the nurse must:

Inform the patient that blood pressure (BP) and electrocardiogram (ECG) monitoring will occur throughout the test The patient will have BP and ECG monitored throughout the test and must be NPO 6 hours before the procedure. The patient is sedated to make him or her comfortable, but will not be heavily sedated. Also, the patient will have an IV line initiated before the procedure.

During a shift assessment, the nurse is identifying the client's point of maximum impulse (PMI). Where should the nurse best palpate the PMI?

Left midclavicular line of the chest at the fifth intercostal space The left ventricle is responsible for the apical beat or the point of maximum impulse, which is normally palpated in the left midclavicular line of the chest wall at the fifth intercostal space.

The nurse is administering a beta blocker to a patient in order to decrease automaticity. Which medication will the nurse administer?

Metoprolol Patients may receive beta-blockers prior to the scan to control heart rate and rhythm.

The physical therapist notifies the nurse that a client with coronary artery disease (CAD) experiences a much greater-than-average increase in heart rate during physical therapy. The nurse recognizes that an increase in heart rate in a client with CAD may result in what?

Myocardial ischemia Unlike other arteries, the coronary arteries are perfused during diastole. An increase in heart rate shortens diastole and can decrease myocardial perfusion. Clients, particularly those with CAD, can develop myocardial ischemia. An increase in heart rate will not usually result in a pulmonary embolism or create electrolyte imbalances. Atrial-septal defects are congenital.

A client has had a myocardial infarction and has been diagnosed as having damage to the layer of the heart responsible for the pumping action. This client experienced damage to what area of the heart?

Myocardium The myocardium is the layer of the heart responsible for the pumping action.

While assessing a client with coronary artery disease following a coronary arteriography, the nurse observes that the client has cool toes, an absent distal peripheral pulse, and a rapid pulse. Which intervention would be most appropriate?

Notify the physician immediately. Absent distal peripheral pulses, cool toes, and pale or cyanotic arms and legs indicate arterial occlusion, usually from a blood clot. These signs as well as a rapid or irregular pulse rate indicate a medical emergency that the nurse must report immediately to the physician. Flexion of the extremity is contraindicated following the procedure.

A critically ill client is admitted to the ICU. The health care provider decides to use intra-arterial pressure monitoring. After this intervention is performed, what assessment should the nurse prioritize?

Perfusion distal to the insertion site The radial artery is the usual site selected. However, placement of a catheter into the radial artery can further impede perfusion to an area that has poor circulation. As a result, the tissue distal to the cannulated artery can become ischemic or necrotic. Vigilant assessment is thus necessary. Alterations in temperature and the development of esophageal varices or compartment syndrome are not high risks.

The nurse is educating a patient at risk for atherosclerosis. What nonmodifiable risk factor does the nurse identify for the patient?

Positive family history The health history provides an opportunity for the nurse to assess patients' understanding of their personal risk factors for coronary artery, peripheral vascular, and cerebrovascular diseases and any measures that they are taking to modify these risks. Risk factors are classified by the extent to which they can be modified by changing one's lifestyle or modifying personal behaviors. Stress, obesity, and hyperlipidemia are all risk factors that can be modified by personal behaviors. Family history is a nonmodifiable risk factor, because it cannot be changed.

The nurse is assessing a patient's blood pressure. What does the nurse document as the difference between the systolic and the diastolic pressure?

Pulse pressure The difference between the systolic and the diastolic pressures is called the pulse pressure.

While auscultating heart sounds, the nurse hears "lub-dub-dee" and recognizes that this would be characterized as which heart sound?

S3 An S3 heart sound is characterized as sounding like "Ken-tuck-y" or "lub-dub-dee." It follows S1 and S2 and is called a ventricular gallop. Although normal in children, it is often an indication of heart failure in an adult. S1 is the first normal heart sound; it sounds like "lub." S2 is the second normal heart sound; it sounds like "dub." An extra sound just before S1 is an S4 heart sound, or atrial gallop. Some say this sound resembles the word "Ten-nes-see" or "lub-lub-dub."

A nurse is describing the process by which blood is ejected into circulation as the chambers of the heart become smaller. The instructor categorizes this action of the heart as what?

Systole Systole is the action of the chambers of the heart becoming smaller and ejecting blood. This action of the heart is not diastole (relaxation), ejection fraction (the amount of blood expelled), or repolarization (electrical charging).

A patient tells the nurse, "I was straining to have a bowel movement and felt like I was going to faint. I took my pulse and it was so slow." What does the nurse understand occurred with this patient?

The patient had a vagal response. When straining during defecation, the patient bears down (the Valsalva maneuver), which momentarily increases pressure on the baroreceptors. This triggers a vagal response, causing the heart rate to slow and resulting in syncope in some patients. Straining during urination can produce the same response. Myocardial infarction is damage to the heart and clients will experience pain or shortness of breath. Anxiety causes the heart rate to increase. The client with an abdominal aortic aneurysm will experience back or abdominal pain, not a decrease in heart rate.

The patient has a heart rate of 72 bpm with a regular rhythm. Where does the nurse determine the impulse arises from?

The sinoatrial node The sinoatrial node, the primary pacemaker of the heart, in a normal resting adult heart has an inherent firing rate of 60 to 100 impulses per minute; however, the rate changes in response to the metabolic demands of the body (Weber & Kelley, 2010).

A patient recently diagnosed with pericarditis asks the nurse to explain what area of the heart is involved. How does the nurse best describe the pericardium to the client?

Thin fibrous sac that encases the heart. The pericardium is a thin, fibrous sac that encases the heart. It is composed of two layers, the visceral and the parietal pericardium. The space between these two layers is filled with fluid.

The nurse is performing an intake assessment on a client with a new diagnosis of coronary artery disease. What would be the most important determination to make during this intake assessment?

Whether the client and involved family members are able to recognize symptoms of an acute cardiac problem and respond appropriately During the health history, the nurse needs to determine if the client and involved family members are able to recognize symptoms of an acute cardiac problem, such as acute coronary syndrome (ACS) or HF, and seek timely treatment for these symptoms. Each of the other listed topics is valid, but the timely and appropriate response to a cardiac emergency is paramount.

Before conducting diagnostic procedures of the cardiovascular system, which baseline data are necessary to collect from a client who is experiencing chest pain?

description of the pain If the client is experiencing chest pain, a history of its location, frequency, and duration is necessary, as is a description of the pain, if it radiates to a particular area, what precipitates its onset, and what brings relief. The nurse weighs the client and measures vital signs. The nurse may measure BP in both arms and compare findings. The nurse assesses apical and radial pulses, noting rate, quality, and rhythm. The nurse also checks peripheral pulses in the lower extremities.

Within the heart, several structures and several layers all play a part in protecting the heart muscle and maintaining cardiac function. The inner layer of the heart is composed of a thin, smooth layer of cells, the folds of which form heart valves. What is the name of this layer of cardiac tissue?

endocardium The inner layer, the endocardium, is composed of a thin, smooth layer of endothelial cells. Folds of endocardium form the heart valves. The middle layer, the myocardium, consists of muscle tissue and is the force behind the heart's pumping action. The pericardium is a saclike structure that surrounds and supports the heart. The outer layer, the epicardium, is composed of fibrous and loose connective tissue.

Which area of the heart is located at the third intercostal (IC) space to the left of the sternum?

erb point Erb point is located at the third IC space to the left of the sternum. The aortic area is located at the second IC space to the right of the sternum. The pulmonic area is at the second IC space to the left of the sternum. The epigastric area is located below the xiphoid process.

The nurse auscultates the apex beat at which anatomical location?

fifth intercostal space, midclavicular line The left ventricle is responsible for the apex beat or the point of maximum impulse, which is normally palpable in the left midclavicular line of the chest wall at the fifth intercostal space. The right ventricle lies anteriorly, just beneath the sternum. Use of inches to identify the location of the apex beat is inappropriate based upon variations in human anatomy. Auscultation below and to the left of the xiphoid process will detect gastrointestinal sounds, but not the apex beat of the heart.

The critical care nurse is caring for a client with a central venous pressure (CVP) monitoring system. The nurse notes that the client's CVP is increasing. This may indicate:

hypervolemia. CVP is a useful hemodynamic parameter to observe when managing an unstable client's fluid volume status. An increasing pressure may be caused by hypervolemia or by a condition, such as heart failure, that results in decreased myocardial contractility. Stress, dislodgment of the catheter, and low magnesium levels would not typically result in increased CVP.

The nurse cares for a client prescribed warfarin orally. The nurse reviews the client's prothrombin time (PT) level to evaluate the effectiveness of the medication. Which laboratory values should the nurse also evaluate?

international normalized ratio (INR) The INR, reported with the PT, provides a standard method for reporting PT levels and eliminates the variation of PT results from different laboratories. The INR, rather than the PT alone, is used to monitor the effectiveness of warfarin. The therapeutic range for INR is 2 to 3.5, although specific ranges vary based on diagnosis. The other laboratory values are not used to evaluate the effectiveness of warfarin.

Each chamber of the heart has a particular role in maintaining cellular oxygenation. Which chamber is responsible for receiving oxygenated blood from the lungs?

left atrium The left atrium receives oxygenated blood from the lungs. The left ventricle pumps that blood to all the cells and tissues of the body. The right atrium receives deoxygenated blood from the venous system. The right ventricle pumps that blood to the lungs to be oxygenated.

Each chamber of the heart has a particular role in maintaining cellular oxygenation. Which chamber is responsible for pumping blood to all the cells and tissues of the body?

left ventricle The left ventricle pumps blood to all the cells and tissues of the body. The left atrium receives oxygenated blood from the lungs. The right ventricle pumps blood to the lungs to be oxygenated. The right atrium receives deoxygenated blood from the venous system.

A client with a hypertensive history has fallen several times in the past two weeks. It is important for this client to rise slowly from a sitting or lying position because gradual changes in position:

provide time for the heart to increase rate of contraction to resupply oxygen to the brain. It is important for the nurse to encourage the client to rise slowly from a sitting or lying position because gradual changes in position provide time for the heart to increase its rate of contraction to resupply oxygen to the brain.

What does decreased pulse pressure reflect?

reduced stroke volume Decreased pulse pressure reflects reduced stroke volume and ejection velocity or obstruction to blood flow during systole. Increased pulse pressure would indicate reduced distensibility of the arteries, along with bradycardia.

Each chamber of the heart has a particular role in maintaining cellular oxygenation. Which chamber is responsible for receiving deoxygenated blood from the venous system?

right atrium The right atrium receives deoxygenated blood from the venous system.

The electrical conduction system of the heart has several components, all of which are instrumental in maintaining polarization, depolarization, and repolarization of cardiac tissue. Which of the conductive structures is known as the pacemaker of the heart?

sinoatrial node The SA node is an area of nerve tissue located in the posterior wall of the right atrium. The SA node is called the pacemaker of the heart because it initiates the electrical impulses that cause the atria and ventricles to contract. When the impulse from the SA node reaches the AV node, it is delayed a few hundredths of a second. While the ventricles fill with blood, the impulse travels from the AV node to the bundle of His, to the right and left bundle branches, and eventually to the Purkinje fibers. Then, both ventricles contract. While the ventricles fill with blood, the impulse travels from the AV node to the bundle of His, to the right and left bundle branches, and eventually to the Purkinje fibers. Then, both ventricles contract.

During auscultation of the lungs, what would a nurse note when assessing a client with left-sided heart failure?

wheezes with wet lung sounds If the left side of the heart fails to pump efficiently, blood backs up into the pulmonary veins and lung tissue. For abnormal and normal breath sounds, the nurse auscultates the lungs. With left-sided congestive heart failure, auscultation reveals a crackling sound, wheezes, and gurgles. Wet lung sounds are accompanied by dyspnea and an effort to sit up to breathe. With left-sided congestive heart failure, auscultation does not reveal a high pitched sound.

Before a transesophageal echocardiogram, a nurse gives a client an oral topical anesthetic spray. When the client returns from the procedure, the nurse observes no active gag reflex. What nursing action is a priority?

withhold food and fluids. Following a transesophageal echocardiogram in which the client's throat has been anesthetized, the nurse should withhold food and fluid until the client's gag reflex returns. There's no indication that oral airway placement would be appropriate. The client should be in the upright position, and the nurse needn't insert an NG tube.