Cardiovascular System Exam Questions

Correct Answer: B

Rationale: An INR of 1.5 is below the therapeutic range for a client on warfarin, indicating that the client may be at risk of clot formation. The nurse's priority action should be to hold the next dose of warfarin to prevent further reduction of the INR. Increasing the dose could potentially lead to an increased risk of bleeding, and continuing the current dose may not be sufficient to bring the INR within the therapeutic range. Monitoring the client's INR closely is important but not the priority action in this scenario.

Correct Answer: C

Rationale: The correct answer is C: Tachycardia. Dobutamine is a medication that primarily increases heart rate (tachycardia) and blood pressure. Therefore, the adverse effects of dobutamine include tachycardia. Choices A, B, and D are incorrect. Heart failure is not an adverse effect of dobutamine; in fact, it is used to treat heart failure by increasing heart contractility. Bradycardia (slow heart rate) is not an expected adverse effect of dobutamine, as it usually increases heart rate. Respiratory distress is not a common adverse effect of dobutamine.

Correct Answer: A

Rationale: The correct answer is A, restrictive cardiomyopathy. This condition specifically involves the stiffening of the heart muscle, leading to a reduced ability to relax and fill with blood between beats. Choice B, hypertrophic cardiomyopathy, is characterized by abnormal thickening of the heart muscle, not stiffening. Choice C, dilated cardiomyopathy, involves the enlargement and weakening of the heart chambers, not stiffening. Choice D, ventricular hypertrophy, refers to the thickening of the walls of the heart's pumping chambers but does not specifically involve the stiffening that is characteristic of restrictive cardiomyopathy.

Correct Answer: A

Rationale: Refractoriness is the correct term to describe the inability of cardiac cells to respond to a new stimulus while they are still in contraction from a previous stimulus. This period is essential for the heart to complete its contraction and relaxation phases without interference. Excitability refers to the ability of cells to respond to stimuli, not the inability to respond. Contractility is the force of cardiac muscle contraction, and automaticity is the ability of cardiac cells to generate electrical impulses spontaneously, which are not relevant to the described scenario.

Correct Answer: A

Rationale: The correct answer is Atrial fibrillation. Atrial fibrillation is indeed a type of abnormal heart rhythm characterized by rapid and irregular beating of the atria. This condition can increase the risk of stroke and heart failure. Choice B, Ventricular fibrillation, is incorrect because it refers to a life-threatening arrhythmia that occurs in the ventricles, not the atria. Choice C, Atrial flutter, is incorrect as it describes a different type of atrial arrhythmia characterized by a regular but fast heartbeat. Choice D, Sinus tachycardia, is incorrect because it is a normal increase in heart rate originating from the sinus node, not an abnormal rhythm.