Question 1

Which of the following criteria are representative of the patient in normal sinus rhythm?

Accepted Answer

The parameters for normal sinus rhythm are heart rate, 60 to 100 beats/min; rhythm, regular; PR interval, 0.12 to 0.20 second; and QRS, 0.06 to 0.10 second.

Question 2

Which of the following interventions should be strictly followed to ensure accurate cardiac output readings?

Accepted Answer

To ensure accurate readings, the difference between injectate temperature and body temperature must be at least 10° C, and the injectate must be delivered within 4 seconds, with minimal handling of the syringe to prevent warming of the solution.This is particularly important when iced injectate is used.

Question 3

Which portion of the ECG is most valuable in diagnosing atrioventricular (AV)conduction disturbances?

Accepted Answer

The PR interval is an indicator of atrioventricular nodal function.The P wave represents atrial depolarization.The QRS complex represents ventricular depolarization, corresponding to phase 0 of the ventricular action potential.The QT interval is measured from the beginning of the QRS complex to the end of the T wave and indicates the total time interval from the onset of depolarization to the completion of repolarization.

Question 4

Which of the following diagnostic tests is most effective for measuring overall heart size?

Accepted Answer

Chest radiography is the oldest noninvasive method for visualizing images of the heart, and it remains a frequently used and valuable diagnostic tool.Information about cardiac anatomy and physiology can be obtained with ease and safety at a relatively low cost.Radiographs of the chest are used to estimate the cardiothoracic ratio and measure overall heart size.

Question 5

The major key to the clinical significance of atrial flutter is the

Accepted Answer

The major factor underlying atrial flutter symptoms is the ventricular response rate.If the atrial rate is 300 and the atrioventricular (AV)conduction ratio is 4:1, the ventricular response rate is 75 beats/min and should be well tolerated.If, on the other hand, the atrial rate is 300 beats/min but the AV conduction ratio is 2:1, the corresponding ventricular rate of 150 beats/min may cause angina, acute heart failure, or other signs of cardiac decompensation.

Question 6

During a history examination, a patient tells the nurse, "The cardiologist says I have a leaking valve." The nurse documents that the patient has a history of

Accepted Answer

Aortic insufficiency is an incompetent aortic valve.If the valve cusps do not maintain this seal, the sound of blood flowing back into the left ventricle during diastole is heard as a decrescendo, high-pitched, blowing murmur.A pericardial friction rub is a sound that can occur within 2 to 7 days after a myocardial infarction.The friction rub results from pericardial inflammation (pericarditis).Classically, a pericardial friction rub is a grating or scratching sound that is both systolic and diastolic, corresponding to cardiac motion within the pericardial sac.Acute mitral regurgitation occurs when the ventricle contracts during systole and a jet of blood is sent in a retrograde manner to the left atrium, causing a sudden increase in left atrial pressure, acute pulmonary edema, and low CO and leading to cardiogenic shock.Chronic mitral regurgitation is auscultated in the mitral area and occurs during systole.It is high pitched and blowing, although the pitch and intensity vary, depending on the degree of regurgitation.As mitral regurgitation progresses, the murmur radiates more widely.

Question 7

The physiologic effect of left ventricular afterload reduction is

Accepted Answer

Afterload is defined as the pressure the ventricle generates to overcome the resistance to ejection created by the arteries and arterioles.After a decrease in afterload, wall tension is lowered.The technical name for afterload is systemic vascular resistance (SVR).Resistance to ejection from the right side of the heart is estimated by calculating the pulmonary vascular resistance (PVR).The PVR value is normally one-sixth of the SVR.

Question 8

A patient with heart failure may be at risk for hypomagnesemia as a result of

Accepted Answer

Hypomagnesemia can be caused by diuresis.Diuretic use with heart failure often contributes to low serum magnesium levels.

Question 9

ST segment monitoring for ischemia has gained increasing importance with the advent of thrombolytic therapy.The most accurate method for monitoring the existence of true ischemic changes is

Accepted Answer

Cardiac biomarkers are proteins that are released from damaged myocardial cells.The initial elevation of cTnI, cTnT, and CK-MB occurs 3 to 6 hours after the acute myocardial damage.This means that if an individual comes to the emergency department as soon as chest pain is experienced, the biomarkers will not have risen.For this reason, it is clinical practice to diagnose an acute myocardial infarction by 12-lead electrocardiography and clinical symptoms without waiting for elevation of cardiac biomarkers.

Question 10

Contractility of the left side of the heart is measured by

Accepted Answer

Contractility of the left side of the heart is measured by the left ventricular stroke work index.

Question 11

Pulsus paradoxus may be seen on intra-arterial blood pressure monitoring when

Accepted Answer

Pulsus paradoxus is a decrease of more than 10 mm Hg in the arterial waveform that occurs during inhalation.It is caused by a fall in CO as a result of increased negative intrathoracic pressure during inhalation.

Question 12

A patient was admitted on the night shift with a diagnosis of acute myocardial infarction.Upon auscultation, the nurse hears a harsh, holosystolic murmur along the left sternal border.The nurse notifies the physician immediately because the symptoms are indicate the patient has developed

Accepted Answer

Ventricular septal rupture is a new opening in the septum between the two ventricles.It creates a harsh, holosystolic murmur that is loudest (by auscultation)along the left sternal border.Papillary muscle rupture is auscultation of a new, high-pitched, holosystolic, blowing murmur at the cardiac apex.Tricuspid stenosis is a quiet murmur that becomes louder with inspiration and is located in the epigastrium area.A pericardial friction rub is a sound that can occur within 2 to 7 days after a myocardial infarction.The friction rub results from pericardial inflammation (pericarditis).Classically, a pericardial friction rub is a grating or scratching sound that is both systolic and diastolic, corresponding to cardiac motion within the pericardial sac.

Question 13

When assessing a patient with PVCs, the nurse knows that the ectopic beat is multifocal because it appears

Accepted Answer

If the ventricular ectopic beats are of various shapes in the same lead, they are multifocal.Multifocal ventricular ectopics are more serious than unifocal ventricular ectopics because they indicate a greater area of irritable myocardial tissue and are more likely to deteriorate into ventricular tachycardia or fibrillation.

Question 14

A patient with a serum potassium level of 6.8 mEq/L may exhibit electrocardiographic changes of

Accepted Answer

Normal serum potassium levels are 3.5 to 4.5 mEq/L.Tall, narrow peaked T waves are usually, although not uniquely, associated with early hyperkalemia and are followed by prolongation of the PR interval, loss of the P wave, widening of the QRS complex, heart block, and asystole.Severely elevated serum potassium (greater than 8 mEq/L)causes a wide QRS tachycardia.

Question 15

The rationale for giving the patient additional fluids after a cardiac catheterization is that

Accepted Answer

Fluid is given for rehydration because the radiopaque contrast acts as an osmotic diuretic.Fluid is also used to prevent contrast-induced nephropathy or damage to the kidney from the contrast dye used to visualize the heart structures.

Question 16

A patient with ventricular fibrillation (VF)is

Accepted Answer

In VF, the patient does not have a pulse, no blood is being pumped forward, and defibrillation is the only definitive therapy.No forward flow of blood or palpable pulse is present in VF.

Question 17

When assessing the pulmonary arterial waveform, the nurse notices dampening.After tightening the stopcocks and flushing the line, the nurse decides to calibrate the transducer.What are two essential components included in calibration?

Accepted Answer

Ensuring accuracy of waveform calibration of the system includes opening the transducer to air and leveling the air-fluid interface of the transducer to the phlebostatic axis.

Question 18

A characteristic event in junctional dysrhythmias is

Accepted Answer

After an ectopic impulse arises in the junction, it spreads in two directions at once.One wave of depolarization spreads upward into the atria and depolarizes them, causing the recording of a P wave on the electrocardiogram.At the same time, another wave of depolarization spreads downward into the ventricles through the normal conduction pathway, producing a normal QRS complex.

Question 19

A patient was admitted to the ICU 3 days ago with a diagnosis of myocardial infarction.The patient is complaining of increased chest pain when coughing, swallowing, and changing positions.The nurse hears a systolic scratching sound upon auscultation of the apical pulse.The nurse notifies the physician.Based on the symptoms, the physician suspects a(n)

Accepted Answer

A pericardial friction rub is a sound that can occur within 2 to 7 days after a myocardial infarction.The friction rub results from pericardial inflammation (pericarditis).Classically, a pericardial friction rub is a grating or scratching sound that is both systolic and diastolic, corresponding to cardiac motion within the pericardial sac.Acute mitral regurgitation occurs when the ventricle contracts during systole and a jet of blood is sent in a retrograde manner to the left atrium, causing a sudden increase in left atrial pressure, acute pulmonary edema, and low CO and leading to cardiogenic shock.Chronic mitral regurgitation is auscultated in the mitral area and occurs during systole.It is high pitched and blowing, although the pitch and intensity vary, depending on the degree of regurgitation.As mitral regurgitation progresses, the murmur radiates more widely.Aortic insufficiency is an incompetent aortic valve.If the valve cusps do not maintain this seal, the sound of blood flowing back into the left ventricle during diastole is heard as a decrescendo, high-pitched, blowing murmur.

Question 20

The mean arterial pressure (MAP)is calculated by

Accepted Answer

The mean arterial pressure is one-third systole and two-thirds diastole.

Quiz 11: Cardiovascular Clinical Assessment and Diagnostic Procedures