TOPIC 2 - EAQS
In caring for the patient with angina the patient states, "I walked to the bathroom. While I was having a bowel movement, I started having the worst chest pain ever. It was similar to the pain I had at home. The pain went away rather quickly." What further assessment data should the nurse obtain from the patient?
"In what areas did you feel this pain?" Using PQRST, the assessment data not volunteered by the patient is the radiation (R) of pain, the area in which the patient felt the pain and if it radiated. The precipitating event (P) was going to the bathroom and having a bowel movement. The quality of the pain (Q) was "like before I was admitted," although a more specific description may be helpful. Severity of the pain (S) was the "worst chest pain ever," although an actual number may be needed. Timing (T) is supplied by the patient describing when the pain occurred and that the patient had had this pain previously. p. 712
The nurse is caring for a patient who survived sudden cardiac death (SCD) that was caused by a lethal ventricular dysrhythmia. The nurse anticipates that which tests will be prescribed to monitor the effectiveness of drug treatment? .
-Exercise stress testing -24-hour Holter monitoring -Signal-averaged electrocardiogram (ECG) -Electrophysiologic study (EPS) under fluoroscopy Because most SCD patients have lethal ventricular dysrhythmias associated with a high recurrence rate, they are closely monitored to assess when they are most likely to have a recurrence and to determine which drug therapies are most effective for them. This monitoring includes exercise stress testing, 24-hour Holter monitoring, signal-averaged electrocardiogram, and an electrophysiologic study done under fluoroscopy. Magnetic resonance imaging is not used to monitor for lethal dysrhythmias. p. 733
The nurse reviews a patient's electrocardiogram (ECG) and determines that the patient is experiencing type I second-degree atrioventricular (AV) block. The nurse made this interpretation based on what ECG characteristics?
-Ventricular rate is slower. -P wave is normal in shape. In type I second-degree AV block, AV conduction is intermittently blocked. Therefore, some P waves are conducted and some are not. Additionally, the ventricular rate may be slower. This is due to nonconducted or blocked QRS complexes and leads to bradycardia. The P wave has a normal shape. Atrial rate is normal. There is progressive lengthening of the PR intervals until another QRS complex is blocked.
A patient experiences prolonged chest pain that is not immediately reversible. The patient's health care provider explains that the cause of the pain is that a once-stable atherosclerotic plaque has ruptured, causing platelet aggregation and thrombus formation. The nurse recognizes this meets the definition of what diagnosis?
Acute coronary syndrome (ACS) When ischemia is prolonged and not immediately reversible, ACS develops. ACS is associated with deterioration of a once stable atherosclerotic plaque that ruptures, exposes the intima to blood, and stimulates platelet aggregation and local vasoconstriction with thrombus formation. The unstable lesion, if partially occlusive, will be manifest as unstable angina or NSTEMI. If there is total occlusion, it is manifest as STEMI.
A patient with chest pain experiences a heart rate of 200 beats/minute and blood pressure of 80/50 mm Hg. The electrocardiogram shows absent P waves. The nurse expects that which intravenous medication will be prescribed?
Adenosine Paroxysmal supraventricular tachycardia (PSVT) is a dysrhythmia starting in an ectopic focus anywhere above the bifurcation of the bundle of His. The symptoms associated with PSVT include hypotension, palpitations, dyspnea, and angina. In PSVT, the heart rate will be greater than 180 beats/minute and the electrocardiogram will often show a hidden P wave. Intravenous adenosine is the standard drug for paroxysmal supraventricular tachycardia. Digoxin, atropine, and vasopressin are not prescribed for paroxysmal supraventricular tachycardia. Digoxin is used in the treatment of atrial fibrillation. Atropine is used in the treatment of junctional escape rhythm. Vasopressin is used in the treatment of asystole. p. 765
A patient reports chest pain. The nurse should assess for which clinical manifestations associated with a myocardial infarction (MI)?
Ashen skin Diaphoresis Nausea and vomiting S 3 or S 4 heart sounds During the initial phase of an MI, catecholamines are released from the ischemic myocardial cells, causing increased sympathetic nervous system (SNS) stimulation. This results in the release of glycogen, diaphoresis, and vasoconstriction of peripheral blood vessels. The patient's skin may be ashen, cool, and clammy (not flushed) as a result of this response. Nausea and vomiting may result from reflex stimulation of the vomiting center by severe pain. Ventricular dysfunction resulting from the MI may lead to the presence of the abnormal S 3 and S 4 heart sounds. p. 720
The nurse observing a telemetry monitor notes that a patient that was in sinus rhythm is now in a different rhythm. The electrocardiogram (ECG) now shows no P waves, fine and wavy lines between the QRS complexes, QRS complexes that measure 0.08 sec, and QRS complexes that occur irregularly with a rate of 120 beats/minute. The nurse correctly interprets this rhythm as what?
Atrial fibrillation Atrial fibrillation is represented on the cardiac monitor by irregular R-R intervals and small fibrillatory (f) waves. There are no normal P waves because the atria are not contracting truly, just fibrillating. Sinus tachycardia is a sinus rate above 100 beats/minute with normal P waves. Ventricular fibrillation is seen on the ECG without a visible P wave, an unmeasurable heart rate, PR, or QRS, and the rhythm is irregular and chaotic. Ventricular tachycardia is seen as three or more premature ventricular contractions (PVCs) that have distorted QRS complexes with regular or irregular rhythm; the P wave usually is buried in the QRS complex without a measureable PR interval. pp. 764, 766
The nurse is caring for a patient 24 hours after the patient was diagnosed with ST segment elevation myocardial infarction (STEMI). The nurse should monitor the patient for what complication of myocardial infarction (MI)?
Cardiac dysrhythmias The most common complication after MI is dysrhythmias, which are present in 80 percent of patients. Unstable angina is considered a precursor to MI rather than a complication. Cardiac tamponade is a rare event, and sudden cardiac death is defined as an unexpected death from cardiac causes. Cardiac dysfunction in the period following an MI would not be characterized as sudden cardiac death. p.720
Which property of the cardiac cell aids in responding mechanically to an impulse?
Contractility Cardiac cells have different properties that are associated with the stimulation and formation of impulse. The property of the cardiac cell to respond mechanically to an impulse is called contractility. The property of the cardiac cell to be electrically stimulated is called excitability. The property of the cardiac cell to initiate an impulse spontaneously and continuously is called automaticity. The property of the cardiac cell to transmit an impulse along a membrane in an orderly manner is called conductivity.
A patient's electrocardiogram (ECG) shows prolonged PR interval, normal P waves, and normal QRS complexes. The patient is asymptomatic and has a normal heart rate and a regular rhythm. The nurse interprets the finding as which type of atrioventricular (AV) block?
First-degree AV block First-degree AV block conducts every impulse to the ventricles with prolonged AV conduction time. In first-degree AV block, heart rate is normal and heart rhythm is regular. The ECG of a patient with first-degree AV block shows normal P wave, prolonged PR interval, and the normal shaped QRS complex. Third degree AV block is suspected if no impulses are conducted from atria to ventricles. Type I second-degree AV block is suspected if the rhythm on the ECG appears as grouped beats. Type II second-degree AV block is suspected if the ventricular rhythm is irregular. pp. 767-768
The nurse assesses an unresponsive patient and reviews the patient's ECG tracing. The nurse determines that the patient is experiencing pulseless electrical activity (PEA). In addition to identifying the cause, what is the priority nursing action?
Initiate cardiopulmonary resuscitation (CPR) PEA is a situation in which organized electrical activity is seen on the ECG, but there is no mechanical heart activity and the patient has no pulse. Treatment begins with CPR followed by drug therapy and intubation. Correcting the underlying cause is critical to prognosis. Applying warm blankets would help with hypothermia but can be completed later. Intubation depends upon the patient's response to cardiopulmonary resuscitation. It is not appropriate to defibrillate; the activity on the ECG is organized. p. 771
The nurse recalls that which artery is most commonly used for bypass graft?
Internal mammary artery Bypass graft surgery involves the replacement of blood vessels that transport blood between the aorta and the blocked coronary artery. The internal mammary artery (IMA) is the most common artery used for bypass graft. The long-term patency rate for an IMA graft is greater than 90 percent after 10 years. Procedures involving the radial, gastroepiploic, or inferior epigastric artery have a comparatively short-term patency rate. p. 725
The nurse is preparing an initial care plan for a patient that presents with chest pain. What is the priority nursing intervention?
Monitoring the patient's ECG A patient with chest pain may have acute coronary syndrome. The priority is to stabilize the patient, determine the plan of care, and prevent complications. Ongoing care should include continuous ECG monitoring. The nurse should help the patient with anxiety and stress to work on the losses due to chronic illness to prevent sudden depression-related cardiac workload. A patient with chronic stable angina is advised to avoid heavy meals and extreme weather to reduce the probability of symptoms. The nurse should encourage verbalization of feelings, perceptions, and fears that increases workload on heart.
The patient is diagnosed with acute coronary syndrome (ACS). The nurse reviews the patient's electrocardiogram (ECG) and notes ST segment depression and T wave inversion. The ECG findings are indicative of what?
Myocardial ischemia The ST depression and T wave inversion on the ECG of a patient diagnosed with ACS indicate myocardial ischemia from an inadequate supply of blood and oxygen to the heart. Myocardial injury is identified with ST-segment elevation. Myocardial infarction is identified with ST-segment elevation and a widened and deep Q wave. A pacemaker's presence is evident on the ECG by a spike leading to depolarization and contraction. p. 776
The nurse is examining the ECG of a patient who has just been admitted with a suspected myocardial infarction (MI). Which ECG change is most indicative of prolonged or complete coronary occlusion?
Pathologic Q wave The presence of a pathologic Q wave, which often accompanies ST segment elevation myocardial infarction (STEMI), is indicative of complete coronary occlusion. Sinus tachycardia, fibrillatory P waves (e.g., atrial fibrillation), or a prolonged PR interval (first-degree heart block) are not direct indicators of extensive occlusion.
Diagnostic tests confirm that a patient has experienced a ST-segment-elevation myocardial infarction (STEMI). The nurse should prepare the patient for what first line of treatment?
Percutaneous coronary intervention (PCI) Emergent PCI is the first line of treatment for patients with confirmed STEMI (i.e., ST-elevation on the ECG and/or positive cardiac biomarkers). The goal is to open the blocked artery within 90 minutes of arrival to a facility that has an interventional cardiac catheterization laboratory. Antiplatelet and statins therapy improves vein graft patency in a patient who has undergone CABG involving the saphenous vein. Dual antiplatelet therapy and heparin will help a patient with ongoing angina and negative cardiac markers. Transmyocardial laser revascularization is used for a patient with advanced coronary artery disease and persistent angina even after maximum medical therapy. p. 722
Which electrocardiogram (ECG) characteristics in a patient with acute coronary syndrome suggests myocardial ischemia?
ST segment depression Typical ECG changes that are seen in myocardial ischemia include ST segment depression and/or T wave inversion. The typical ECG change seen during an acute myocardial infarction is ST segment elevation. Depression of the ST segment and T wave inversion occurs in response to an inadequate supply of blood and oxygen, which causes an electrical disturbance in the myocardial cells. Pathologic Q waves may be seen in patients with a myocardial infarction. ST segment elevation may be seen in myocardial injury.
A patient is scheduled for a coronary artery bypass graft (CABG) surgery. The nurse reviews the surgical plan and notes that the type of graft that will be used is prone to future stenosis and graft occlusion. Therefore the nurse anticipates postoperative use of antiplatelet and statin therapy to improve graft patency. Which type of graft will be used for the surgery?
Saphenous vein graft Coronary artery bypass graft surgery (CABG) involves the replacement of conduits that transport blood between the aorta and the coronary artery. A patient with a saphenous vein graft may develop intimal hyperplasia, which contributes to stenosis and graft occlusions. This patient should receive antiplatelet therapy and statins after surgery to improve vein graft patency. A patient with radial artery CABG should receive calcium channel blockers and long-acting nitrates to control coronary spasms. A patient with gastroepiploic artery CABG generally has a high graft patency rate; the chances of graft-related problems are very rare. A patient with CABG of the internal mammary artery has an average graft patency of more than 90 percent, even after 10 years. A patient with high graft patency rates may not require any medication to maintain the patency of the graft. p. 725
The nurse monitors the electrocardiogram (ECG) of a patient diagnosed with acute coronary syndrome. The patient's baseline rhythm is sinus rhythm. Which additional ECG findings are most suggestive of myocardial infarction?
T-wave inversion Pathologic Q wave Elevated ST segment Typical ECG changes that are seen in myocardial infarction include ST-segment elevation (not depression), T-wave inversion, and a pathologic Q wave. The patient will not have premature atrial contractions.
A patient is hospitalized following a 3-day history of heart palpitations and dizziness. The patient's electrocardiogram (ECG) shows the following rhythm. The nurse identifies that the patient is at risk for what?
Stroke A risk of atrial fibrillation is clot formation in the atria caused by altered blood flow through the heart. If the clot forms on the right side of the heart, it can travel to the lungs, causing a pulmonary embolism. If the clot forms on the left side of the heart, the risk is of it traveling to the brain, causing a stroke or an embolism to other arteries in the body. The risk of an embolus is particularly high when the patient converts back to a normal sinus rhythm. To reduce the risk of clot formation in the heart, most patients with chronic atrial fibrillation are on some type of anticoagulation. Coumadin (Warfarin) often is prescribed. p. 766
Which statement describes the electrical activity of the heart represented by the PR interval on an electrocardiogram (ECG)?
The length of time for the electrical impulse to travel from the sinoatrial (SA) node to the Purkinje fibers. The electrical impulse in the heart must travel from the SA node through the AV node and into the Purkinje fibers for synchronous atrial and ventricular contraction to occur. When measuring the PR interval (the time from the beginning of the P wave to the beginning of the QRS), the nurse is identifying the length of time it takes for the electrical impulse to travel from the SA node to the Purkinje fibers. The P wave represents the length of time it takes for the impulse to travel from the SA node through the atrium, causing depolarization of the atria (atrial contraction). Atrial repolarization occurs during ventricular depolarization and is hidden by the QRS complex. The length of time it takes for the electrical impulse to travel from the SA node to the AV node is the flat line between the end of the P wave and the beginning of the Q wave on the ECG and usually is not measured.
The nurse reviews the cardiac cycle and ectopic impulses. The nurse identifies that the greatest risk to the patient is when the ectopy occurs in which part of the cycle?
The patient is at greatest risk if the ectopic impulse falls on the T wave of a preceding beat. This is called the R-on-T phenomenon. This is especially dangerous because the PVC is firing during the relative refractory period of ventricular repolarization. Excitability of the heart cells increases during this time, and the risk for the PVC to start VT or ventricular fibrillation (VF) is great. pp. 768-769
The nurse is preparing to perform an electrocardiogram (ECG) on a patient. The nurse observes artifact on the monitor. What are possible causes of the artifact?
The patient is shivering. Electrical interference is present. The leads and electrodes are not secure. Muscle activity caused by shivering of the patient, electrical interference, or loose leads and electrodes can cause distorted baseline and waveforms called artifact on the electrocardiogram (ECG). Oily skin is wiped dry with alcohol to prepare the patient for ECG. Electrodes may have to be replaced if conductive gel has dried out. p. 760
A patient tells the nurse, "I had severe chest pain six days ago." The nurse identifies that which cardiac biomarker will be most helpful in determining whether the patient had a myocardial infarction at the time the patient experienced chest pain?
Troponin Troponin is a serum cardiac marker that is detectable in the blood up to two weeks after myocardial injury and is used to diagnose a myocardial infarction. Troponin has two subtypes: cardiac-specific troponin T (cTnT) and cardiac-specific troponin I (cTnI). Serum levels of cTnT and cTnI increase 4 to 6 hours after the onset of myocardial injury, peak at 10 to 24 hours, and return to baseline over 10 to 14 days. Myoglobin is a protein found in skeletal and cardiac muscle. It is a sensitive indicator of early myocardial injury but is not specific for cardiac muscle; therefore it is not used to diagnose a myocardial infarction. Myoglobin peaks and returns to normal in 3 to 15 hours. Homocysteine is a protein. High levels of homocysteine may indicate an increased risk for coronary artery disease. It is not used to diagnose myocardial infarction. CK levels begin to rise about 6 hours after an MI, peak at about 18 hours, and return to normal within 24 to 36 hours. p. 722
The nurse recognizes that which cardiac dysrhythmia is life-threatening and necessitates immediate intervention?
Ventricular fibrillation Ventricular fibrillation is a life-threatening dysrhythmia that requires immediate intervention. During ventricular fibrillation, the ventricles are quivering and are no longer able to contract to produce effective cardiac output. Because there is no cardiac output, the body is left without oxygenation. Sinus tachycardia requires treatment to slow the rate to 60 to 100 beats/minute. Atrial fibrillation requires treatment to convert the rhythm back to a normal sinus rhythm with one atrial contraction for every ventricular contraction. Normal sinus rhythm, in which the rate is 60 to 100 beats/minute, requires no treatment. p. 770
