MSNCB Cardiac Nursing 3 — Questions and Answers
Question 1: A patient with an implantable cardioverter-defibrillator (ICD) receives an appropriate shock. After the event, the priority nursing intervention is to:
- Immediately call the electrophysiology team to reprogram the device
- Assess the patient's hemodynamic status and level of consciousness (Correct answer)
- Apply a magnet over the device to disable further shocks
- Restrict all activity and place the patient on bed rest for 48 hours
Correct answer: Assess the patient's hemodynamic status and level of consciousness
Following an ICD shock, the nurse must first assess the patient's hemodynamic status and consciousness to determine if the device successfully terminated the dysrhythmia.
Question 2: A patient with mitral stenosis is most likely to develop which complication due to left atrial enlargement?
- Right ventricular hypertrophy from increased preload
- Atrial fibrillation due to atrial wall distension (Correct answer)
- Aortic regurgitation from valve annulus dilation
- Pulmonary embolism from right-sided thrombus
Correct answer: Atrial fibrillation due to atrial wall distension
Left atrial enlargement from mitral stenosis stretches atrial muscle fibers, disrupting electrical conduction and predisposing the patient to atrial fibrillation.
Question 3: When teaching a patient about warfarin therapy after mechanical heart valve replacement, the nurse emphasizes which dietary instruction?
- Increase vitamin K-rich foods to maintain therapeutic levels
- Eliminate all vitamin K-containing foods from the diet
- Maintain consistent vitamin K intake to stabilize INR (Correct answer)
- Supplement daily with vitamin K to counteract warfarin effects
Correct answer: Maintain consistent vitamin K intake to stabilize INR
Consistent intake of vitamin K-rich foods is recommended because sudden changes in vitamin K consumption cause unpredictable INR fluctuations.
Question 4: A patient's telemetry shows P waves that are upright in lead II, a PR interval of 0.24 seconds, and a QRS of 0.08 seconds. This rhythm is best described as:
- Junctional rhythm with retrograde P waves
- First-degree atrioventricular block (Correct answer)
- Second-degree AV block, Mobitz type I
- Bundle branch block with prolonged conduction
Correct answer: First-degree atrioventricular block
A PR interval greater than 0.20 seconds with consistent 1:1 AV conduction and normal QRS indicates first-degree AV block.
Question 5: A patient is admitted with decompensated heart failure and started on a dobutamine infusion. The nurse understands this medication primarily acts to:
- Reduce preload by dilating venous capacitance vessels
- Increase myocardial contractility via beta-1 receptor stimulation (Correct answer)
- Lower afterload by blocking peripheral alpha-1 receptors
- Reduce heart rate to improve ventricular filling time
Correct answer: Increase myocardial contractility via beta-1 receptor stimulation
Dobutamine is a beta-1 adrenergic agonist that increases myocardial contractility and cardiac output in patients with severely reduced ejection fraction.
Question 6: A nurse is caring for a patient after coronary artery bypass graft (CABG) surgery. Which finding in the first 24 hours requires the most immediate attention?
- Chest tube drainage of 80 mL/hr
- Temperature of 37.8°C (100°F)
- Mediastinal drainage suddenly decreasing to 5 mL/hr (Correct answer)
- Serum glucose of 160 mg/dL
Correct answer: Mediastinal drainage suddenly decreasing to 5 mL/hr
Sudden decrease in mediastinal drainage after CABG may indicate tube occlusion and impending cardiac tamponade, requiring immediate assessment.
Question 7: Which hemodynamic profile is most consistent with cardiogenic shock?
- Low PCWP, low CO, low SVR
- High PCWP, low CO, high SVR (Correct answer)
- Low PCWP, high CO, low SVR
- High PCWP, high CO, low SVR
Correct answer: High PCWP, low CO, high SVR
Cardiogenic shock presents with elevated PCWP (pulmonary congestion), low cardiac output (pump failure), and elevated SVR (compensatory vasoconstriction).
MSNCB Cardiac Nursing 3
A patient with an implantable cardioverter-defibrillator (ICD) receives an appropriate shock.
After the event, the priority nursing intervention is to: