ATI RN
Cardiovascular System Exam Questions
1. Where is the impulse from the SA node delayed, enabling atrial contraction to complete before the ventricles are stimulated and contract?
- A. AV node
- B. Bundle of His
- C. SA node
- D. Aorta
Correct answer: A
Rationale: The correct answer is AV node. The AV node is responsible for delaying the impulse from the SA node, allowing the atria to contract before the ventricles. This delay ensures the effective pumping of blood in a coordinated manner. Choices B, C, and D are incorrect because the Bundle of His is responsible for transmitting the impulse to the Purkinje fibers, the SA node is the pacemaker of the heart responsible for initiating the heartbeat, and the aorta is the main artery carrying oxygenated blood from the heart to the body, respectively, none of which are involved in delaying the impulse to allow atrial contraction before ventricular contraction.
2. What is the amount of tension the ventricle must develop during contraction to eject blood from the left ventricle into the aorta?
- A. Afterload
- B. Preload
- C. Automaticity
- D. Ejection fraction
Correct answer: A
Rationale: Afterload is the correct answer because it refers to the pressure or tension that the ventricle must overcome during systole to eject blood into the aorta. Preload, on the other hand, is the degree of stretch of the ventricular muscle at the end of diastole before it contracts. Automaticity is the ability of the heart to generate electrical impulses independently, and ejection fraction is the percentage of blood pumped out of the ventricle with each heartbeat. Therefore, in the context of the question, afterload best describes the amount of tension the ventricle must develop to eject blood into the aorta.
3. The client on warfarin has an INR of 3.8. What is the most appropriate action by the nurse?
- A. Administer vitamin K.
- B. Hold the next dose of warfarin.
- C. Increase the dose of warfarin.
- D. Notify the healthcare provider immediately.
Correct answer: A
Rationale: An INR of 3.8 is elevated, indicating an increased risk of bleeding. Administering vitamin K can help reverse the effects of warfarin. Holding the next dose of warfarin would be appropriate if the INR was too high, but not as the first-line action. Increasing the dose of warfarin would worsen the situation by further increasing the INR. Notifying the healthcare provider is important, but immediate action to address the elevated INR is necessary.
4. This term refers to a change in the inotropic state of the muscle without a change in myocardial fiber length.
- A. Contractility
- B. Excitability
- C. Refractoriness
- D. Automaticity
Correct answer: A
Rationale: The correct answer is A: Contractility. Contractility specifically refers to the change in the force of contraction of the heart muscle without changing its length. In this scenario, the focus is on the change in the inotropic state of the muscle, which directly relates to contractility. Choice B, Excitability, refers to the ability of a cell to respond to a stimulus, not specifically related to changes in contractile force. Choice C, Refractoriness, pertains to the period during which a cell is unresponsive to a new stimulus. Choice D, Automaticity, refers to the ability of cardiac cells to spontaneously generate electrical impulses.
5. Which condition involves the enlargement and weakening of the left ventricle of the heart, leading to reduced pumping ability?
- A. Dilated cardiomyopathy
- B. Hypertrophic cardiomyopathy
- C. Restrictive cardiomyopathy
- D. Pericarditis
Correct answer: A
Rationale: The correct answer is A: Dilated cardiomyopathy. Dilated cardiomyopathy is characterized by the enlargement and weakening of the left ventricle of the heart, which results in a reduced ability to pump blood effectively. Choice B, Hypertrophic cardiomyopathy, involves thickening of the heart muscle, not enlargement. Choice C, Restrictive cardiomyopathy, is characterized by stiffening of the heart muscle, not enlargement. Choice D, Pericarditis, refers to inflammation of the pericardium, the lining surrounding the heart, and does not involve enlargement and weakening of the left ventricle.
Similar Questions
Access More Features
ATI RN Basic
$69.99/ 30 days
- 5,000 Questions with answers
- All ATI courses Coverage
- 30 days access
ATI RN Premium
$149.99/ 90 days
- 5,000 Questions with answers
- All ATI courses Coverage
- 30 days access