CH 35: Diagnostic Studies Flashcards

Question

A nurse is educating a group of nursing students about CK-MB. Which statements are correct? (SATA) A. CK-MB is specific to the heart muscle. B. CK-MB levels start rising 3–6 hours after MI. C. CK-MB is the preferred biomarker for diagnosing acute MI. D. CK-MB levels return to baseline within 12–48 hours. E. CK-MB can be elevated in skeletal muscle injury.

Answer 1

A. CK-MB is specific to the heart muscle. B. CK-MB levels start rising 3–6 hours after MI. D. CK-MB levels return to baseline within 12–48 hours. Rationale: CK-MB is specific to the heart and rises 3–6 hours after MI, peaking within 12–24 hours and returning to normal in 12–48 hours. It is no longer the preferred biomarker for diagnosing MI since troponin is more specific.

Answer 2

B. Initiate a blood transfusion as prescribed. Rationale: A hemoglobin level of 8 g/dL is significantly low, affecting oxygen delivery to tissues. A transfusion is indicated for symptomatic anemia, especially in patients with cardiovascular disease.

Answer 3

A. They provide results within 1–3 hours of myocardial injury. Rationale: High-sensitivity troponin assays detect myocardial injury within 1–3 hours, allowing for faster diagnosis and treatment of acute MI.

Answer 4

A. Prothrombin time (PT) B. Activated partial thromboplastin time (aPTT) C. International normalized ratio (INR) Rationale: PT, aPTT, and INR measure clotting times and are crucial for patients at risk of thrombosis or bleeding. Hemoglobin and RBC count assess oxygen-carrying capacity but do not directly indicate clotting risk.

Answer 5

D. Troponin is the most specific test, so myocardial infarction is unlikely. Rationale: Troponin is more specific for myocardial infarction. CK-MB can be elevated due to other causes, including skeletal muscle injury, making troponin the preferred diagnostic test.

Answer 6

B. Heart failure Rationale: Chronic heart failure can lead to anemia due to reduced kidney perfusion and decreased erythropoietin production.

Answer 7

D. Start anticoagulation therapy and continuous ECG monitoring. Rationale: A rising troponin level strongly suggests myocardial infarction, requiring immediate management, including anticoagulation and continuous cardiac monitoring.

Answer 8

B. The patient has an increased risk for future cardiovascular events. Rationale: Elevated CRP levels are associated with systemic inflammation and atherosclerosis. A high CRP level is a predictor of future cardiovascular events rather than an indication of an active myocardial infarction.

Answer 9

A. CRP is produced by the liver during periods of inflammation. C. High CRP levels are linked to an increased risk of atherosclerosis. D. CRP levels can help predict future cardiovascular events. Rationale: CRP is an inflammatory marker produced by the liver. Elevated CRP is associated with atherosclerosis and can help predict future cardiovascular events, but it is not specific for diagnosing myocardial infarction like troponin.

Answer 10

B. The elevated CRP level is a response to systemic inflammation. Rationale: CRP is an acute-phase protein that rises in response to systemic inflammation, including infections and chronic conditions like atherosclerosis. It is not specific to cardiovascular disease but can indicate increased cardiovascular risk when persistently elevated.

Answer 11

D. The patient has an increased risk of cardiovascular disease. Rationale: Elevated homocysteine (Hcy) levels are associated with an increased risk for cardiovascular disease (CVD), peripheral vascular disease (PVD), and stroke. Hcy testing is particularly useful in patients with a family history of early CVD but without other common risk factors.

Answer 12

A. Vitamin B6 deficiency B. Vitamin B12 deficiency D. Folate deficiency Rationale: Homocysteine is an amino acid produced during protein metabolism. Vitamin B6, B12, and folate deficiencies impair its metabolism, leading to elevated levels. High dietary protein intake does not directly contribute, and regular exercise does not increase homocysteine levels.

Answer 13

B. A 45-year-old with a strong family history of early cardiovascular disease Rationale: Homocysteine testing is recommended for patients with a family history of early CVD or those who have CVD without common risk factors. While hypertension and hyperlipidemia are risk factors for CVD, homocysteine testing is not typically ordered unless there is a strong family history or unexplained cardiovascular events.

Answer 14

A. Increase intake of vitamin B6-, B12-, and folate-rich foods. Rationale: Elevated homocysteine levels are often due to deficiencies in vitamin B6, B12, and folate. Increasing dietary intake of these vitamins through sources like leafy greens, fortified cereals, eggs, and lean meats can help lower homocysteine levels and reduce cardiovascular risk.

Answer 15

C. The patient is experiencing heart failure exacerbation. Rationale: BNP is primarily released from the ventricles in response to increased diastolic pressure, such as in heart failure (HF). A significantly elevated BNP level is a key indicator of HF and helps distinguish it from respiratory causes of dyspnea, such as COPD or pulmonary embolism.

Answer 16

A. BNP is released from the ventricles in response to increased diastolic pressure. C. BNP and NT-pro-BNP promote natriuresis and diuresis. D. NT-pro-BNP has a longer half-life than BNP. Rationale: BNP is released from the ventricles in response to increased diastolic pressure, helping to diagnose heart failure. Both BNP and NT-pro-BNP promote natriuresis (sodium excretion) and diuresis to reduce fluid overload. NT-pro-BNP is more sensitive but less specific than BNP and has a longer half-life. BNP is used to differentiate cardiac from respiratory causes of dyspnea, not diagnose a respiratory disorder.

Answer 17

C. Moderate to severe heart failure Rationale: BNP levels correlate with the severity of heart failure. A BNP level greater than 400 pg/mL is strongly suggestive of heart failure. Levels exceeding 900 pg/mL indicate moderate to severe heart failure.

Answer 18

D. NT-pro-BNP levels are higher in elderly patients, but heart failure cannot be ruled out. Rationale: NT-pro-BNP levels naturally increase with age, making interpretation in elderly patients more complex. While levels tend to be higher, a result of 600 pg/mL does not rule out heart failure, especially in a symptomatic patient.

Answer 19

B. BNP 800 pg/mL Rationale: A BNP level above 400 pg/mL is strongly indicative of heart failure. D-dimer is used to assess for blood clots (e.g., pulmonary embolism), troponin detects myocardial injury, and ABG changes are nonspecific to HF.

Answer 20

A. Age B. Kidney function C. Obesity Rationale: BNP levels can be influenced by age (they naturally rise in older adults) and kidney function (renal insufficiency can lead to higher levels due to impaired clearance). Obesity is associated with lower BNP levels, which may mask heart failure. Steroid use and hemoglobin A1c levels do not significantly affect BNP interpretation.

Answer 21

B. Coronary artery disease (CAD) Rationale: Elevated total cholesterol, LDL, and triglycerides, along with low HDL, are strong risk factors for CAD. LDL contributes to plaque formation, while HDL plays a protective role.

Answer 22

A. LDL cholesterol contributes to plaque formation in the arteries. B. HDL cholesterol helps remove excess cholesterol from the bloodstream. C. VLDL is primarily composed of triglycerides. D. Chylomicrons transport dietary fats from the intestines to the liver. Rationale: LDL contributes to atherosclerosis, HDL helps remove cholesterol from tissues, VLDL is primarily triglycerides, and chylomicrons transport dietary fat. Increased HDL is protective, reducing CAD risk.

Answer 23

C. High risk for CAD Rationale: An LDL level of 160 mg/dL or higher is considered a major risk factor for CAD.

Answer 24

C. Low due to her high HDL level Rationale: A high HDL level (above 60 mg/dL) is protective and reduces the risk of CAD, even if total cholesterol or LDL levels are borderline.

Answer 25

D. 6 Rationale: The cholesterol-to-HDL ratio is calculated as total cholesterol ÷ HDL. A ratio above 5 increases CAD risk.

Answer 26

A. Obesity B. Smoking C. Sedentary lifestyle E. Excessive alcohol intake Rationale: Obesity, smoking, lack of exercise, and alcohol intake raise LDL and triglycerides. A high-fiber diet lowers LDL levels.

Answer 27

C. “Increased Lp(a) levels are linked to an increased risk of atherosclerosis.” Rationale: High Lp(a) levels are a risk factor for atherosclerosis and CAD, especially in women.

Answer 28

A. Increased risk for CAD Rationale: Lp-PLA2 is an inflammatory enzyme found in atherosclerotic plaques. High levels indicate increased CAD risk.

Answer 29

B. Replacing saturated fats with unsaturated fats Rationale: Unsaturated fats (found in fish, nuts, and olive oil) help lower LDL, while saturated fats (in red meat and dairy) increase LDL.

Answer 30

D. Is the major protein in LDL and strongly predicts CAD risk. Rationale: Apo B is the primary protein in LDL and is a stronger predictor of CAD than LDL alone.

Answer 31

A. Chylomicrons transport dietary fat from the intestines. C. HDL removes excess cholesterol from tissues. D. VLDL is rich in endogenous triglycerides. E. Increased HDL is protective against CAD. Rationale: LDL is mostly cholesterol, not triglycerides. The other statements are correct.

Answer 32

C. HDL Rationale: Apo A-I is the main protein in HDL and helps remove cholesterol from tissues, reducing CAD risk.

Answer 33

A. Avoid food for 12 hours before the test. Rationale: A fasting lipid panel requires at least 8-12 hours of fasting for accurate triglyceride and LDL measurements.

Answer 34

C. >60 mg/dL Rationale: HDL levels above 60 mg/dL are protective against CAD.

Answer 35

D. Total cholesterol:HDL ratio Rationale: The total cholesterol to HDL ratio is a key predictor of CAD risk.

Answer 36

B. “You should remain still during the test to prevent artifacts.” Rationale: A 12-lead ECG requires the patient to remain still to reduce motion artifact, which can interfere with accurate recording. The test is painless and does not require fasting or physical activity.

Answer 37

C. “I can remove the electrodes at night for comfort.” Rationale: The electrodes must remain in place continuously during the 24–48 hour monitoring period to ensure accurate data collection.

Answer 38

D. Records heart rhythms only when activated by the patient during symptoms. Rationale: Event monitors capture transient cardiac events by recording when activated, which allows detection of infrequent arrhythmias.

Answer 39

B. Myocardial infarction Rationale: ST-segment elevation is a hallmark of acute myocardial infarction due to myocardial ischemia.

Answer 40

B. To detect ventricular late potentials and risk for ventricular tachycardia Rationale: SAECG is used to identify late potentials, which indicate a risk for ventricular tachycardia.

Answer 41

D. Notify the provider, as the electrodes may need to be repositioned Rationale: Skin irritation is a common issue, and the provider may need to adjust electrode placement while maintaining accurate monitoring.

Answer 42

A. “This device continuously records my heart rhythm for 24 hours.” Rationale: Unlike Holter monitors, ECG event monitors do not record continuously; they capture cardiac events when activated.

Answer 43

A. The diary helps correlate symptoms with ECG changes. Rationale: A symptom diary allows healthcare providers to match patient-reported symptoms with ECG abnormalities.

Answer 44

C. “This test will record your heart’s electrical activity from multiple angles.” Rationale: A 12-lead ECG provides a comprehensive view of electrical activity from different perspectives.

Answer 45

C. Event monitors can capture infrequent arrhythmias over a longer period. Rationale: Event monitors are useful for detecting intermittent arrhythmias that may not occur within a 24-hour Holter monitoring period.

Answer 46

B. Over large muscle groups to reduce artifact Rationale: Limb leads should be placed over muscle to ensure stable electrode contact and reduce artifact.

Answer 47

B. Wet skin reduces the effectiveness of the electrodes. Rationale: Moisture can cause electrodes to detach, leading to inaccurate data collection.

Answer 48

B. Identifies small electrical signals that may trigger arrhythmias. Rationale: SAECG detects ventricular late potentials that increase the risk for ventricular tachycardia.

Answer 49

A. Call 911 if experiencing severe chest pain or dizziness. Rationale: Patients should seek emergency care if experiencing serious cardiac symptoms.

Answer 50

A. A patient with daily chest pain episodes Rationale: Holter monitoring is most useful for detecting frequent but intermittent arrhythmias over a 24–48 hour period.

Answer 51

c. “I should avoid taking my oxygen with me during the test, even though I use it daily.” Rationale: Patients who use oxygen routinely should carry or pull it with them during the test to ensure adequate oxygenation.

Answer 52

c. “Avoid caffeine for at least 24 hours before the test.” Rationale: Caffeine can interfere with test results by affecting heart rate and should be avoided for 24 hours before the stress test.

Answer 53

c. ST-segment depression on ECG Rationale: ST-segment depression is a sign of myocardial ischemia, indicating inadequate blood flow to the heart muscle. The test should be stopped immediately.

Answer 54

b. Have the patient sit down and assess vital signs. Rationale: Safety is the priority. The nurse should stop the test, assess the patient’s condition, and determine the need for further intervention.

Answer 55

c. “The test can help identify heart problems even if you do not have symptoms.” Rationale: Stress testing is useful in detecting underlying cardiac conditions that may not present with obvious symptoms.

Answer 56

b. Beta-blocker Rationale: Beta-blockers may be held for 24 hours before a stress test because they can blunt the heart rate response, affecting test results.

Answer 57

d. “This procedure is only performed in the operating room.” Rationale: Noninvasive hemodynamic monitoring is commonly used in perioperative settings, critical care units, and emergency departments, not just in the OR.

Answer 58

a. “It is based on your age and calculated by subtracting your age from 220.” Rationale: The predicted peak heart rate for a stress test is determined by subtracting the patient’s age from 220.

Answer 59

d. The patient has persistent ST-segment changes on ECG. Rationale: Persistent ST-segment changes indicate ongoing myocardial ischemia, requiring immediate medical evaluation.

Answer 60

b. Obtain a baseline set of vital signs. Rationale: Baseline vital signs provide a reference point to evaluate the patient’s response to the test and detect any abnormalities.

Answer 61

b. Ask the patient if they have had any recent x-rays and check for possible pregnancy. Rationale: Before performing a chest x-ray, it is important to assess the frequency of recent x-rays and check for pregnancy due to the potential risks associated with radiation exposure.

Answer 62

a. Ask the patient about allergies, especially to iodine or contrast materials. Rationale: It is important to assess for allergies to iodine or contrast materials, as these can cause serious allergic reactions during a CT with IV contrast.

Answer 63

c. To evaluate coronary artery calcification for heart disease risk Rationale: EBCT is primarily used to assess coronary artery calcification, which is an important indicator of heart disease risk.

Answer 64

a. Congestive heart failure Rationale: Pulmonary edema is a common finding in congestive heart failure due to the accumulation of fluid in the lungs as a result of left-sided heart failure.

Answer 65

b. No further action is required unless the patient develops symptoms Rationale: A low calcium score suggests minimal or no coronary artery disease, and no immediate intervention is needed unless symptoms arise.

Answer 66

b. The patient’s renal function, especially creatinine levels Rationale: IV contrast can affect kidney function, so assessing renal function (especially creatinine levels) is important to prevent contrast-induced nephropathy.

Answer 67

a. a. “Radiation exposure is minimized, and lead shielding is used to protect areas not being imaged.” Rationale: Radiation exposure is minimized during x-rays, and lead shielding is used to protect areas not being imaged from unnecessary exposure.

Answer 68

d. “The contrast used in this procedure may make you feel very hot and flushed.” Rationale: The IV contrast used in cardiac CT can cause a warm, flushed sensation, which is a common and benign side effect.

Answer 69

b. The patient’s renal function, allergies, and pregnancy status Rationale: Before a CMRI, the nurse must assess renal function, allergies, and pregnancy status to ensure the patient’s safety during the procedure, especially since it involves contrast materials.

Answer 70

a. Ensuring that the patient remains still to avoid image distortion Rationale: The patient must lie completely still during the CMRI to obtain clear images, as any movement can distort the results.

Answer 71

c. “You may need to fast for several hours, and a β-blocker may be given to control your heart rate.” Rationale: The patient may need to fast prior to the procedure, and a β-blocker may be administered to control heart rate, which is essential for accurate imaging during CTA.

Answer 72

b. Obtain IV access and assess for a contrast allergy Rationale: Before the CTA, the nurse must ensure IV access is established for contrast injection and assess for any contrast allergies to avoid allergic reactions.

Answer 73

b. The presence of implanted metallic devices or metal fragments Rationale: CMRI is contraindicated for patients with implanted metallic devices or metal fragments, as the magnetic field can interfere with these devices, posing a risk to the patient.

Answer 74

d. Notify the healthcare provider to determine the need for further intervention Rationale: An irregular heart rhythm can interfere with the accuracy of CTA results. The nurse should notify the healthcare provider to determine the appropriate action, which may include further interventions or rescheduling the test.

Answer 75

a. To assess for wall motion abnormalities in patients unable to exercise Rationale: A pharmacologic echocardiogram uses medications like adenosine to simulate the stress response in patients who cannot undergo exercise stress testing, allowing assessment of wall motion abnormalities.

Answer 76

b. Obtain baseline vital signs and ensure IV access for drug administration Rationale: Baseline vital signs should be obtained and IV access established before administering pharmacologic agents such as adenosine or dobutamine to ensure patient safety during the procedure.

Answer 77

b. Instruct the patient to refrain from caffeine consumption for 12 hours prior Rationale: Caffeine can interfere with the imaging results by affecting the heart’s response during the test, so it is important for the patient to avoid caffeine 12 hours before the procedure.

Answer 78

b. Checking for allergies to contrast medium and the presence of implanted metallic devices Rationale: MRA involves the use of gadolinium contrast medium, and it is contraindicated for patients with allergies to this substance or implanted metallic devices, so the nurse must assess for these factors beforehand.

Answer 79

c. The arms must be held in position to minimize artifacts and improve image quality Rationale: Holding the arms in position during the scan helps reduce artifacts in the imaging and ensures the best possible image quality.

Answer 80

b. Monitoring the patient for ECG changes during the procedure Rationale: The MUGA scan requires continuous ECG monitoring during the procedure to obtain accurate timing of cardiac events and ensure proper image acquisition.

Answer 81

c. Pregnancy or potential pregnancy Rationale: Pregnant patients or those who could be pregnant should avoid pharmacologic nuclear imaging procedures due to potential risks to the fetus from radiation exposure and the medications used during the test.

Answer 82

b. The patient’s history of allergies and metal implants Rationale: It is essential to assess for allergies to contrast medium and the presence of metal implants, as MRI procedures can be dangerous for patients with certain metallic implants.

Answer 83

c. Dyspnea, dizziness, and nausea Rationale: These are common side effects of vasodilators like adenosine, dipyridamole, and regadenoson used during pharmacologic nuclear imaging. The nurse should monitor for these symptoms and be prepared to administer aminophylline if needed.

Answer 84

c. Administer aminophylline if prescribed Rationale: Aminophylline is used to reverse the side effects of dipyridamole (dyspnea, dizziness, and nausea) and should be administered if ordered by the healthcare provider.

Answer 85

d. “You may feel some pressure and mechanical movement from the transducer during the procedure.” Rationale: Patients undergoing echocardiography may feel pressure or mechanical movement from the transducer as it is used to capture sound waves from the heart.

Answer 86

b. To measure the effect of various cardiac drugs on heart function Rationale: MUGA scans are commonly used to assess cardiac function, including the effects of cardiac or cardiotoxic drugs on heart performance.

Answer 87

c. Asking the patient to lie with their arms extended overhead for 20 minutes Rationale: The patient must lie still, often with arms extended overhead, to minimize artifacts and ensure accurate imaging during nuclear perfusion imaging.

Answer 88

d. “You will need to stay still during the scan with your arms extended overhead.” Rationale: The patient needs to stay still to ensure high-quality images and may be asked to extend their arms to minimize artifacts during the nuclear imaging scan.

Answer 89

A. “Blood glucose levels must be within a specific range to ensure accurate results.” Rationale: PET scans use fluoro-18-deoxyglucose to assess myocardial metabolic activity, which competes with circulating glucose. If blood glucose levels are too high or too low, the uptake of the tracer may be altered, leading to inaccurate results. The optimal range is 60-140 mg/dL (3.3-7.8 μmol/L).

Answer 90

C. “You will need to lie completely still during the scan.” Rationale: Movement can interfere with the imaging and affect the accuracy of results. While a short fasting period may be required, 12 hours is unnecessary. Caffeine and tobacco restrictions are more specific to stress tests rather than SPECT scans. Increased fluid intake is encouraged after the scan to help excrete the radioactive isotope.

Answer 91

A. The patient has a history of dysphagia. Rationale: A history of dysphagia raises concerns about the patient’s ability to swallow the probe safely, increasing the risk of aspiration. A sore throat is a minor concern, and dentures will be removed before the procedure. Mild anxiety is common and can be addressed with patient education and possibly sedation.

Answer 92

B. “I can take a short break between exercise and the imaging.” Rationale: Post-exercise images must be taken within 1 minute to accurately compare wall motion before and after stress. Any delay could lead to misinterpretation of results.

Answer 93

C. Severe dyspnea Rationale: Severe dyspnea may indicate bronchospasm or an adverse reaction to vasodilators such as regadenoson or dipyridamole. This requires immediate intervention, potentially with aminophylline to reverse the effects. Mild nausea, flushing, and fatigue are common and generally resolve without intervention.

Answer 94

A. A patient with a history of severe GERD Rationale: Severe GERD increases the risk of esophageal irritation, bleeding, or perforation during TEE. While pacemakers and artificial heart valves do not prevent a TEE, patients on beta-blockers may require adjustments due to their effect on heart rate during imaging.

Answer 95

A. “You can eat and drink immediately after the test.” Rationale: The gag reflex must return before the patient can eat or drink to prevent aspiration. A sore throat is expected, and sedation requires monitoring and a designated driver if done outpatient.

Answer 96

D. “The first tracer checks for blood flow, and the second evaluates how your heart cells use glucose.” Rationale: Nitrogen-13-ammonia assesses myocardial perfusion, while fluoro-18-deoxyglucose evaluates metabolic function. A mismatch indicates ischemia or damage.

Answer 97

A. Encourage fluid intake Rationale: Fluids help flush out the radioactive tracer used in the test. Deep breathing is unnecessary, and NPO status is not required post-test. A bronchodilator is only needed if the patient experiences bronchospasm.

Answer 98

B. “I drank some coffee this morning.” Rationale: Caffeine should be avoided before certain nuclear tests, especially if combined with stress testing. Jewelry must be removed, but it does not require immediate intervention. A light meal is usually acceptable, and anxiety is common.

Answer 99

C. A patient with asthma Rationale: Regadenoson and dipyridamole can trigger bronchospasm, making them dangerous for patients with asthma. Beta-agonists like aminophylline may be needed to reverse symptoms. GERD, hypertension, and anemia are not major concerns.

Answer 100

C. “Most of the tracer will lose its radioactivity within a few hours.” Rationale: Most radioactive tracers used in PET scans decay quickly, usually within a few hours. Patients are advised to drink fluids to enhance elimination. No special medication is required.

Answer 101

D. Atrial fibrillation Rationale: The patient’s ECG findings are irregularly irregular rhythm, absent P waves, and a narrow QRS complex, which are hallmark features of atrial fibrillation (AFib). In AFib, chaotic atrial depolarizations replace normal P waves, and impulses reach the AV node irregularly, leading to an unpredictable ventricular response.

Answer 102

C. Educating the patient on lifestyle modifications and possible beta-blocker therapy Rationale: The patient has PVCs and NSVT but no symptoms of syncope or hemodynamic instability. In this case, lifestyle modifications (reducing caffeine, alcohol, and stress) and beta-blockers (e.g., metoprolol) are first-line treatments to reduce ventricular ectopy.

Answer 103

A. “Avoid caffeine for 24 hours before the test.” C. “You should wear comfortable clothing and walking shoes.” D. “Stop eating at least 4 hours before the test.” E. “If you develop chest pain during the test, inform the technician immediately.” Rationale: * Caffeine should be avoided for 24 hours as it can alter test results, particularly if vasodilators like adenosine or regadenoson are used in pharmacologic stress testing. * Comfortable clothing and walking shoes are essential since the patient will be walking or running on a treadmill. * Fasting for at least 4 hours before the test prevents nausea and reduces insulin-related fluctuations that could affect the ECG. * Reporting chest pain during the test is critical as it may indicate myocardial ischemia requiring test termination. * Metformin is often held the day of the test due to the risk of lactic acidosis if contrast dye is used in follow-up imaging.

Answer 104

C. Prepare the patient for emergent percutaneous coronary intervention (PCI) Rationale: The ST-segment elevation in leads II, III, and aVF suggests an inferior wall myocardial infarction (MI), which is a medical emergency requiring immediate reperfusion therapy (PCI or thrombolysis).

Answer 105

C. Administering IV calcium gluconate Rationale: The ECG findings of tall, peaked T waves, a widened QRS complex, and a prolonged PR interval are indicative of severe hyperkalemia, which can cause life-threatening arrhythmias.

Answer 106

A. “You will wear this monitor for 2 to 4 weeks and press a button to record ECG activity when you feel symptoms.” Rationale: An event monitor is ideal for capturing intermittent arrhythmias that do not occur daily. Unlike a Holter monitor, which records continuously for 24–48 hours, an event monitor allows patients to record ECG activity only when symptoms occur, increasing the likelihood of detecting abnormalities. Additionally, this test can be used for up to 4 weeks, making it superior for identifying infrequent dysrhythmias.

Answer 107

D. “This test requires me to stop my blood thinners before sending my heart data.” Rationale: Event monitoring is a non-invasive procedure that does not require stopping anticoagulant therapy (e.g., warfarin, DOACs). Blood thinners are crucial for preventing stroke in atrial fibrillation patients and should never be stopped unless specifically instructed by a healthcare provider.

Answer 108

B. “An ILR is implanted under your skin and continuously records your heart rhythm for months to years, making it ideal for capturing rare events.” Rationale: An ILR is the best option for patients with infrequent but potentially serious arrhythmias (e.g., unexplained syncope) because it provides long-term continuous monitoring (months to years). This increases the likelihood of detecting rare but significant rhythm disturbances that may not be captured by short-term monitoring methods.

Answer 109

A. “You must keep electrodes attached to your skin at all times.” B. “Press the button when you feel symptoms so the device can record your ECG activity.” D. “Your ECG data can be transmitted to your healthcare provider in real-time or analyzed later.” E. “If you experience severe chest pain, dizziness, or shortness of breath, seek emergency medical attention instead of just pressing the button.” Rationale: The external event monitor requires continuous skin electrode attachment to ensure proper function. Patients must press the button when experiencing symptoms to capture the ECG rhythm at that moment. Many event monitors can transmit data in real time or store it for later analysis. In cases of severe symptoms, such as chest pain or shortness of breath, the patient should seek emergency care instead of relying solely on the monitor.

Answer 110

A. “These apps use wrist-based sensors or finger contact to detect and record your heart rhythm, which you can share with your healthcare provider.” Rationale: Smartphone ECG applications allow patients to check their heart rhythm by placing their fingers on a sensor or using a wrist-based device. The recorded data can then be saved or transmitted to a healthcare provider for evaluation. This technology is useful for tracking atrial fibrillation episodes and detecting irregular rhythms.

Answer 111

A. To assess how the heart responds to increased oxygen demand during physical exertion Rationale: An exercise stress test evaluates the heart’s response to physical stress by monitoring ECG and BP changes during exertion. This helps to detect coronary artery disease (CAD), exercise-induced ischemia, and arrhythmias that may not be evident at rest. This test is particularly useful in patients with symptoms that occur only with activity and can help determine exercise tolerance and safe activity levels.

Answer 112

B. The patient had an MI 3 days ago and still experiences chest pain at rest Rationale: A recent myocardial infarction (within 3-5 days) and unstable angina (chest pain at rest) are contraindications to exercise stress testing. This test increases myocardial oxygen demand, which can provoke ischemia, worsening the patient’s condition. Patients with recent cardiac events should undergo further evaluation and stabilization before any stress testing.

Answer 113

A. Instruct the patient to avoid caffeine and smoking for at least 24 hours before the test C. Ensure the patient wears comfortable clothing and walking shoes for the test D. Explain that ECG and blood pressure will be monitored throughout the exercise period E. Inform the patient that chest pain or severe shortness of breath should be reported immediately during the test Rationale: Patients should avoid caffeine and smoking for at least 24 hours before the test, as these can affect heart rate and blood pressure. Comfortable clothing and proper footwear are important for safe exercise. Continuous ECG and BP monitoring are necessary to detect cardiac abnormalities. Patients must report symptoms like chest pain or shortness of breath immediately to prevent complications.

Answer 114

B. The patient has significant functional limitations and may require further intervention Rationale: The 6-minute walk test assesses cardiac and respiratory endurance. A short walking distance with significant dyspnea or fatigue suggests poor functional capacity, which is common in heart failure and other cardiovascular conditions. These findings may prompt further evaluation and treatment adjustments.

Answer 115

D. “This test evaluates your baseline functional capacity and can monitor your response to treatment over time.” Rationale: The 6-minute walk test is a general measure of cardiac and pulmonary fitness that helps assess a patient’s exercise tolerance and response to treatment over time. It is commonly used in older adults, heart failure patients, and those undergoing rehabilitation.

Answer 116

C. Immediately stop the test and place the patient in a supine position Rationale: ST-segment depression and chest pain indicate myocardial ischemia, which can progress to a heart attack. The test must be stopped immediately to prevent further cardiac stress. Placing the patient in a supine position helps improve circulation, and further interventions (e.g., oxygen, nitroglycerin, ECG monitoring) may be needed.

Answer 117

C. Heart failure Rationale: A chest x-ray showing cardiomegaly and pulmonary congestion is highly suggestive of heart failure. Cardiomegaly indicates an enlarged heart, often due to chronic volume overload or myocardial dysfunction. Pulmonary congestion results from fluid backing up into the lungs, leading to dyspnea, crackles, and lower extremity edema. These findings are characteristic of heart failure, particularly left-sided heart failure.

Answer 118

B. “A chest x-ray can show if your heart is enlarged or if there is fluid buildup around it.” Rationale: A chest x-ray assesses the size, shape, and position of the heart and can identify conditions such as cardiomegaly, pericardial effusion, and pulmonary congestion. However, it does not provide detailed images of coronary arteries, measure cardiac output, or detect arrhythmias. Those require specialized tests like coronary angiography, echocardiography, or electrocardiography (ECG).

Answer 119

A. Instruct the patient to remove any metallic objects or jewelry from the chest and neck area B. Inform the patient that the procedure is noninvasive and painless D. Verify that the patient is not pregnant before proceeding with the x-ray E. Explain that the patient must hold their breath while the x-ray is taken Rationale: Before a chest x-ray, the nurse should ensure that the patient removes all metal objects to prevent interference with imaging, confirm that the patient is not pregnant, and explain that breath-holding is required for clear images. The procedure is noninvasive and painless. IV contrast is not required for a routine chest x-ray but is used for more advanced imaging, such as CT scans.

Answer 120

A. Mitral stenosis Rationale: Mitral stenosis is characterized by thickened, immobile mitral valve leaflets leading to impaired blood flow from the left atrium to the left ventricle. This causes exertional dyspnea, fatigue, and reduced cardiac output. Rheumatic fever is a common cause of mitral stenosis, and echocardiography is the gold standard for diagnosis.

Answer 121

D. Systolic heart failure Rationale: Ejection fraction measures the percentage of blood ejected from the left ventricle during systole. A normal EF is 55-70%. An EF of 35% indicates systolic heart failure, where the ventricle is unable to pump effectively, leading to reduced cardiac output and fluid overload.

Answer 122

A. Explain that the procedure is noninvasive and painless D. Inform the patient that sedation is not required E. Position the patient in a left lateral position during the test Rationale: A **TTE is noninvasive, does not require sedation, and is performed with the patient in the left lateral position to improve imaging. Unlike a TEE, fasting is not required since no sedation or esophageal intubation is involved.

Answer 123

B. Esophageal stricture Rationale: TEE requires passing an endoscope through the esophagus, so conditions like esophageal stricture, dysphagia, or prior radiation therapy to the chest can increase the risk of esophageal perforation.

Answer 124

B. Coronary artery disease (CAD) affecting the LAD Rationale: Stress echocardiography assesses myocardial function during increased oxygen demand. Hypokinesis in a specific region suggests ischemia due to CAD, particularly in the LAD territory.

Answer 125

C. Patent foramen ovale (PFO) Rationale: A bubble study detects right-to-left shunting, which is seen in PFO or atrial septal defects.

Answer 126

A. Esophageal perforation B. Dysrhythmias C. Stroke E. Vasovagal reaction Rationale: TEE complications include esophageal trauma, dysrhythmias, stroke (due to embolization), and vasovagal reactions. Pneumothorax is not a risk since the lungs are not directly involved.

Answer 127

C. Increases heart rate and myocardial oxygen demand Rationale: Dobutamine is a beta-agonist that increases heart rate and myocardial contractility, simulating exercise. This helps assess for ischemic changes on echocardiography.

Answer 128

A. Transesophageal echocardiogram (TEE) Rationale: TEE provides better visualization of posterior heart structures, including the mitral valve, without interference from the chest wall.

Answer 129

A. Valvular regurgitation Rationale: Color Doppler identifies abnormal blood flow patterns, and mixed colors suggest turbulent regurgitant flow.

Answer 130

A. Heart failure B. Atrial fibrillation C. Myocardial infarction E. Valvular disease Rationale: Echocardiography is used for heart failure, atrial fibrillation (to check for clots), MI (to assess wall motion), and valvular disease. It is not used for deep vein thrombosis.

Answer 131

B. Transesophageal echocardiogram (TEE) Rationale: TEE provides better visualization of the left atrium compared to TTE since the esophagus is closer to the posterior heart structures. Left atrial thrombus is a concern in atrial fibrillation and must be ruled out before cardioversion to prevent embolization.

Answer 132

A. Mitral regurgitation B. Aortic stenosis D. Tricuspid regurgitation E. Atrial septal defect Rationale: Color Doppler visualizes the speed and direction of blood flow, making it useful for identifying valvular disorders (mitral and tricuspid regurgitation, aortic stenosis) and congenital defects (atrial septal defect). Left ventricular hypertrophy is best evaluated by 2D echocardiography.

Answer 133

B. M-mode provides a single-dimensional view, while 2D echocardiography provides cross-sectional views Rationale: M-mode records intracardiac structure motion along a single US beam, measuring wall thickness and chamber size. 2D echocardiography provides a cross-sectional view of heart structures to assess spatial relationships.

Answer 134

A. Vasodilation of normal coronary arteries Rationale: Dipyridamole is a vasodilator that increases coronary blood flow in healthy arteries. Diseased arteries do not dilate as well, allowing for detection of ischemia on echocardiography.

Answer 135

A. “You will need to remain NPO for at least 6 hours before the procedure.” B. “Sedation will be used, so you will need someone to drive you home.” C. “You may experience a sore throat after the procedure.” Rationale: TEE requires NPO status due to sedation and esophageal intubation. A sore throat is common post-procedure. The patient should be positioned in a left lateral position, not completely flat. Unlike a TTE, TEE is semi-invasive.

Answer 136

B. It is a noninvasive test with less radiation exposure Rationale: Coronary CTA is noninvasive, requires less radiation than cardiac catheterization, and is useful for visualizing coronary circulation. However, cardiac catheterization remains the gold standard for diagnosing CAD and allows for intervention if blockages are found.

Answer 137

A. The patient must be in normal sinus rhythm B. IV contrast may be used, requiring an allergy assessment D. The patient should avoid caffeine before the test Rationale: Coronary CTA requires normal sinus rhythm for accurate imaging. IV contrast is often used, so an allergy assessment is necessary. Caffeine should be avoided before the test to prevent increased heart rate, which can interfere with imaging. The test is noninvasive and is not recommended for pregnant women due to radiation exposure.

Answer 138

A. Detecting early coronary artery calcification Rationale: A calcium-scoring CT scan detects calcium deposits in coronary plaque before symptoms appear, helping to predict the risk of future cardiac events. It does not measure myocardial perfusion, structural heart defects, or valve function.

Answer 139

B. It detects coronary calcium deposits in plaques Rationale: EBCT is the most common method used for calcium-scoring CT scans, detecting coronary calcium deposits and helping assess the risk of coronary artery disease (CAD).

Answer 140

A. Irregular heart rhythms B. Excessive movement during the scan C. Presence of a pacemaker E. Tachycardia Rationale: Irregular heart rhythms (Atrial fibrillation, PVCs) can distort images. Patient movement can reduce scan clarity. A pacemaker can cause artifacts that interfere with image quality. Tachycardia affects scan accuracy because higher heart rates make it harder to capture clear images. IV contrast (D) does not interfere with accuracy but is required for some CT scans.

Answer 141

C. Cardiac catheterization Rationale: Cardiac catheterization is the gold standard for diagnosing coronary artery disease (CAD) and allows for immediate intervention (angioplasty or stent placement) if blockages are found.

Answer 142

A. History of iodine allergy Rationale: IV contrast used in cardiac CT scans contains iodine, which can cause severe allergic reactions in sensitive individuals. Pre-medication with steroids or antihistamines may be needed, or an alternative imaging test should be considered.

Answer 143

A. The test involves radiation exposure B. IV contrast dye may cause allergic reactions D. It may not be suitable for patients with arrhythmias E. It can detect coronary artery calcium deposits Rationale: Coronary CTA exposes the patient to radiation, requires IV contrast, and is less effective in patients with arrhythmias due to motion artifacts. It cannot fully replace cardiac catheterization, as intervention (angioplasty/stenting) cannot be performed with CTA alone. It can detect calcium deposits in coronary arteries.

Answer 144

C. Calcium-scoring CT scan Rationale: A calcium-scoring CT scan is noninvasive and helps detect coronary artery calcium deposits, which can indicate early coronary artery disease (CAD) before symptoms develop. It is useful for risk assessment in asymptomatic patients with a strong family history.

Answer 145

A. It provides radiation-free imaging Rationale: One of the main advantages of CMRI is that it does not involve radiation, making it a safer option for patients who require multiple imaging tests, especially when monitoring heart function over time.

Answer 146

A. Myocardial infarction (MI) B. Congenital heart disorders C. Coronary artery disease (CAD) D. Aortic disorders Rationale: CMRI is useful for diagnosing myocardial infarction (MI), congenital heart disorders, coronary artery disease (CAD), and aortic disorders. It is not typically used to diagnose ventricular arrhythmias, as other diagnostic tools like EKGs are more effective for this purpose.

Answer 147

A. The patient must have a new model pacemaker that is MRI-compatible Rationale: Newer models of pacemakers are MRI-compatible, but older models may be affected by the magnetic fields, potentially altering their function. CMRI should not be performed immediately after pacemaker placement, and patients are not required to fast.

Answer 148

B. Cardiovascular magnetic resonance imaging (CMRI) Rationale: CMRI is highly sensitive in detecting even small myocardial infarctions (MIs), providing three-dimensional imaging that can reveal subtle changes in myocardial tissue that might not be visible with SPECT or other tests.

Answer 149

C. CMRI should be postponed until 6 weeks after stent placement Rationale: Patients with coronary stents are generally advised to wait 6 weeks after the procedure before undergoing CMRI to ensure the stent is securely in place and to minimize the risk of dislodging the stent during imaging.

Answer 150

D. The MRI may interfere with the device’s function Rationale: The strong magnetic field of CMRI can interfere with the function of older model pacemakers and ICDs, potentially altering their settings or causing malfunctions. However, newer models of pacemakers and ICDs are MRI-compatible and can be safely used during CMRI.

Answer 151

D. The extent of ischemic injury to the myocardium CMRI is particularly useful for assessing myocardial damage and ischemic injury caused by coronary artery disease (CAD). While it does not directly assess coronary stenosis or plaque composition, it can evaluate the effects of CAD, such as areas of ischemic injury and heart function post-infarction.

Answer 152

A. To assess ventricular wall motion and ejection fraction (EF) Rationale: The MUGA scan primarily provides information about ventricular wall motion during systole and diastole and is used to assess ejection fraction (EF), an important indicator of heart function.

Answer 153

C. To assess coronary blood flow changes with exercise or pharmacologic stress Rationale: Stress perfusion imaging is used to assess changes in coronary blood flow with exercise or pharmacological agents, helping to diagnose CAD and determine the severity of ischemia or blood flow abnormalities.

Answer 154

A. Coronary artery disease (CAD) B. Viability of myocardial tissue D. Success of coronary artery bypass surgery (CABG) Rationale: Stress perfusion imaging is used to assess CAD, determine myocardial tissue viability, and evaluate the success of interventions like coronary artery bypass surgery (CABG). It is not typically used to diagnose heart valve abnormalities or left ventricular hypertrophy.

Answer 155

D. Higher sensitivity for detecting myocardial ischemia and viability Rationale: PET offers high sensitivity for detecting myocardial ischemia and assessing the viability of myocardial tissue, making it an increasingly popular choice for evaluating CAD and other heart conditions.

Answer 156

A. When the patient has no contraindications to physical exercise Rationale: Exercise stress perfusion imaging is preferred when the patient is physically able to exercise and has no contraindications. It provides the most accurate assessment of coronary blood flow and ischemia under physical stress.

Answer 157

B. Technetium, Thallium, or Sestamibi Rationale: Common SPECT imaging agents include Technetium, Thallium, and Sestamibi, which help assess myocardial perfusion and ischemia in CAD patients. Rubidium-82 is used in PET scans, and regadenoson and adenosine are pharmacologic agents used for stress testing.

Answer 158

A. Obesity Rationale: Obesity can lead to false-positive results in SPECT imaging due to difficulty in obtaining clear images, which can cause misinterpretation of coronary perfusion. Other factors, such as multivessel coronary disease, may lead to false-negative results.

Answer 159

D. To dilate coronary arteries and simulate the effects of exercise Rationale: IV adenosine is used to dilate coronary arteries, simulating the effects of exercise for patients who cannot perform physical activity. This allows for stress testing and evaluation of myocardial perfusion and ischemia.

Answer 160

A. To assess intracardiac pressures, oxygen levels, and ejection fraction (EF) Rationale: Cardiac catheterization is primarily used to measure intracardiac pressures, oxygen levels, cardiac output (CO), and ejection fraction (EF), as well as to visualize the coronary arteries and heart chambers.

Answer 161

C. To visualize the coronary arteries and detect blockages Rationale: Coronary angiography, performed during left-sided heart catheterization, is used to visualize the coronary arteries and identify any blockages, allowing for the assessment of coronary artery disease (CAD).

Answer 162

A. Bleeding or hematoma at the puncture site B. Infection at the catheter insertion site D. Thrombus formation E. Stroke Rationale: Common complications of cardiac catheterization include bleeding or hematoma at the puncture site, infection, thrombus formation, and stroke. Electrolyte imbalances are not typically considered a direct complication of the procedure.

Answer 163

A. Femoral, internal jugular, subclavian, or antecubital vein Rationale: For right-sided cardiac catheterization, the catheter is inserted through veins, such as the femoral, internal jugular, subclavian, or antecubital veins. This allows the catheter to access the right side of the heart.

Answer 164

B. Flushed sensation Rationale: Patients typically report a temporary flushed sensation when the contrast media is injected during cardiac catheterization. This is a common, non-harmful reaction.

Answer 165

A. Radial femoral or brachial artery Rationale: For left-sided heart catheterization, the catheter is typically inserted into the radial, femoral, or brachial artery and then advanced retrogradely up to the left ventricle.

Answer 166

C. To assess the left-sided heart function Rationale: PAWP is measured during right-sided cardiac catheterization to estimate left-sided heart function, particularly the left atrial pressure, which provides insight into the function of the left side of the heart.

Answer 167

D. Femoral artery Rationale: A common insertion site for left-sided cardiac catheterization is the femoral artery, through which the catheter is passed retrograde to the left side of the heart.

Answer 168

A. Heart rate and blood pressure Rationale: Heart rate and blood pressure must be closely monitored during cardiac catheterization to detect potential complications, such as dysrhythmias, bleeding, or hypotension.

Answer 169

C. Incorrect measurement of blood pressure Rationale: If the catheter becomes kinked or looped, it may result in incorrect measurement of intracardiac pressures, which can affect the diagnosis and management of cardiac conditions.

Answer 170

B. To assess the composition, location, and thickness of plaque in the coronary arteries Rationale: IVUS is primarily used to evaluate the composition, location, and thickness of plaque within the coronary arteries, providing detailed information on the health of the arterial walls.

Answer 171

A. 3D or 2D images Rationale: IVUS provides 2D or 3D images of the arterial walls of the coronary arteries, offering a detailed cross-sectional view of the blood vessels.

Answer 172

A. By inserting a small catheter with a miniature transducer to obtain ultrasound images from within the artery Rationale: IVUS involves inserting a small catheter with a miniature transducer into the artery to obtain ultrasound images of the arterial walls, which helps assess plaque composition and arterial health.

Answer 173

B. Coronary angiography Rationale: IVUS is commonly performed alongside coronary angiography to provide detailed information about plaque and arterial wall health during coronary interventions.

Answer 174

D. Monitoring for bleeding or hematoma at the catheter insertion site Rationale: Post-procedure care after IVUS is similar to care after cardiac catheterization, with a focus on monitoring for bleeding or hematoma at the catheter insertion site and other potential complications.

Answer 175

A. Vessel response to treatments such as stent placement and atherectomy Rationale: IVUS is useful for evaluating how the coronary arteries respond to treatments such as stent placement and atherectomy, providing detailed feedback on the effectiveness of these interventions.

Answer 176

B. To determine the source and treatment of dysrhythmias Rationale: EPS is primarily used to identify the source and determine the appropriate treatment for dysrhythmias, particularly in patients at risk for sudden cardiac death.

Answer 177

C. By inserting them into the heart chambers Rationale: During EPS, electrodes are placed inside the heart chambers to record and manipulate the heart’s electrical activity, helping to assess the function of the SA node, AV node, and ventricular conduction.

Answer 178

B. Sudden cardiac death Rationale: Patients with symptomatic tachydysrhythmias are at high risk for sudden cardiac death, making accurate diagnosis and treatment critical.

Answer 179

D. Cardiac catheterization Rationale: Post-procedure nursing care after EPS is similar to that of a patient following a cardiac catheterization, with a focus on monitoring for bleeding and ensuring patient stability.

Answer 180

A. Conduction patterns of the SA node, AV node, and ventricles Rationale: EPS provides detailed information on the electrical conduction of the heart, including the SA node, AV node, and ventricles, to help assess and treat dysrhythmias.

Answer 181

D. To evaluate chest pain and assess heart function and major vessels Rationale: Cardiac catheterization with coronary angiography is used to evaluate chest pain, measure pressures within the heart, and assess the patency of the coronary arteries to identify any blockages or circulatory issues.

Answer 182

D. Assess vital signs often and monitor ECG continuously Rationale: After an EPS, nurses need to monitor vital signs frequently and provide continuous ECG monitoring to ensure there are no complications, such as dysrhythmias or hemodynamic instability.

Answer 183

C. Withhold antidysrhythmic drugs and keep the patient NPO for 6–8 hours Rationale: Antidysrhythmic drugs are often stopped several days before the EPS to ensure accurate test results. Patients should also be kept NPO for 6–8 hours before the procedure.

Answer 184

B. To determine if angioplasty or stenting is needed for nonsignificant blockages Rationale: FFR helps assess whether angioplasty or stenting is needed for nonsignificant blockages in coronary arteries by measuring pressure and flow to determine the severity of the blockage.

Answer 185

D. Inspect the insertion site for bleeding or swelling Rationale: After IVUS, which is done during cardiac catheterization, nurses should assess the insertion site for complications such as bleeding or swelling, just like other invasive catheterization procedures.

Answer 186

C. Assess for contrast media allergy and explain the sensation of the contrast injection Rationale: Before peripheral arteriography, the nurse should assess for contrast media allergy and explain to the patient that they may experience a warm sensation or salty taste after the contrast is injected.

Answer 187

C. Monitor the patient for allergic reactions to the contrast media Rationale: During peripheral arteriography, the nurse should closely monitor the patient for potential allergic reactions to the contrast media. This is a key responsibility to ensure patient safety during the procedure.

Answer 188

B. Inspect the insertion site for bleeding or swelling Rationale: After peripheral arteriography, the nurse must inspect the insertion site for complications such as bleeding or swelling and check the extremity for proper pulsation, warmth, and color.

Answer 189

B. A warm sensation and a salty taste Rationale: Patients may experience a warm sensation and a salty taste immediately after the contrast injection during peripheral arteriography due to the contrast medium.

Answer 190

B. To assess the size, consistency, and location of plaque in the arteries Rationale: IVUS is used to assess the blood vessel patency, size, and consistency of plaque and evaluate the effectiveness of coronary artery treatments.

Answer 191

A. To ensure accurate electrical activity recording during the study Rationale: Antidysrhythmic drugs are withheld before EPS to avoid interference with the heart’s electrical activity, ensuring accurate test results.

Answer 192

B. To correct electrical conduction issues or manage dysrhythmias Rationale: Pacemakers or ICDs may be inserted during EPS to correct electrical conduction problems or to manage dysrhythmias, especially if the procedure identifies a need for immediate intervention.

Answer 193

D. Severe renal impairment Rationale: Severe renal impairment is a potential contraindication due to the contrast media used in peripheral arteriography, which could further affect kidney function

Answer 194

a. Monitoring vital signs and ECG b. Checking the catheter insertion site and distal pulses

Answer 195

d. B-type natriuretic peptide (BNP) Rationale: Levels of BNP are a marker for heart failure. The other laboratory results would assess for myocardial infarction (troponin) or the risk for coronary artery disease (Hcy and LDL).

Answer 196

b. A flushed feeling is common when the contrast dye is injected. Rationale: A sensation of warmth or flushing is common when the contrast material is injected, which can be anxiety producing unless it has been discussed with the patient. The patient may receive a sedative drug before the procedure but monitored anesthesia care is not used. Arterial pressure monitoring is not routinely used after the procedure to monitor blood pressure. The patient is not immobile during cardiac catheterization and may be asked to cough or take deep breaths.

Answer 197

d. Keep a diary of daily activities while the monitor is worn. Rationale: The patient is taught to keep a diary describing daily activities while Holter monitoring is being accomplished to help correlate any rhythm disturbances with patient activities. Patients are taught that they should not take a shower or bath during Holter monitoring and that they should continue with their usual daily activities. The recorder stores the information about the patient‘s rhythm until the end of the testing, when it is removed and the data are analyzed.

Answer 198

a. Troponins Rationale: Cardiac troponins start to elevate 4 to 6 hours after myocardial injury and are highly specific to myocardium. They are the preferred diagnostic marker for myocardial infarction. High-sensitivity troponin (hs-cTnT, hs-cTnI) assays provide even earlier detection of a heart event, within 1-3 hours. Myoglobin rises in response to myocardial injury within 30 to 60 minutes but is nonspecific and rapidly cleared from the body, limiting its use in the diagnosis of myocardial infarction. Creatine kinase (CK-MB) increases 4 to 6 hours after myocardial injury but is rarely used now for diagnosis of acute MI. Homocysteine (Hcy) is an amino acid that is made during protein catabolism. Elevated levels of Hcy are linked to a higher risk of CVD, peripheral vascular disease, and stroke.

Answer 199

b. Instruct the patient to lie still. Rationale: The patient should remain still during the scan. The procedure is rapid and involves little risk, so none of the other actions are necessary.

Answer 200

c. The patient has a permanent cardiac pacemaker. Rationale: MRI is discouraged in those with older model pacemakers and ICDs because the magnets can change the function of the devices. However, when there is a strong clinical need and the benefits outweigh the risks, MRI can be done at centers experienced in this procedure. It will be important to determine the type of pacemaker. Many newer models of pacemakers and ICDs are approved for use with MRI.

Answer 201

c. Inversion of T waves on the electrocardiogram Rationale: ECG changes associated with coronary ischemia (such as T-wave inversions and ST segment depression) indicate that the myocardium is not getting adequate O 2 delivery and that the exercise test should be stopped immediately. Increases in BP and heart rate are normal responses to aerobic exercise. Feeling tired is also normal as the intensity of exercise increases during the stress testing.

Answer 202

b. The patient is allergic to contrast dye. Rationale: Patients who have allergies to contrast dye will require treatment with medications, such as corticosteroids and antihistamines before the angiogram. The other information may be communicated to the health care provider but will not require a change in the usual pre-cardiac catheterization orders or medications.

Answer 203

c. Place the patient on NPO status. Rationale: The patient will need to be NPO for 6 hours preceding the TEE, so the nurse should place the patient on NPO status as soon as the order is received. The other actions also will need to be accomplished but not until just before or during the procedure.

Answer 204

a. High troponin I level Rationale: The elevation in troponin I indicates that the patient has had an acute myocardial infarction. Further assessment and interventions are indicated. The other laboratory results indicate increased risk for coronary artery disease but are not associated with acute cardiac problems that need immediate intervention.

CH 35: Diagnostic Studies Flashcards

pages 786-794