Nursing Elites

1. What is the term that describes the inability of cardiac cells to respond to a new stimulus while they are still in contraction from a previous stimulus?

• A. Refractoriness
• B. Excitability
• C. Contractility
• D. Automaticity

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.

2. What is a condition where the heart muscle becomes thickened without an obvious cause, leading to a reduction in the heart's ability to pump blood?

• A. Hypertrophic cardiomyopathy
• B. Dilated cardiomyopathy
• C. Restrictive cardiomyopathy
• D. Myocarditis

Correct answer: A

Rationale: Hypertrophic cardiomyopathy is the correct answer. It is a condition characterized by the abnormal thickening of the heart muscle without an obvious cause, which impairs the heart's ability to effectively pump blood. Dilated cardiomyopathy (choice B) involves the enlargement and weakening of the heart chambers, not thickening. Restrictive cardiomyopathy (choice C) refers to the stiffening of the heart muscle, limiting its ability to fill properly. Myocarditis (choice D) is inflammation of the heart muscle usually caused by a viral infection, not thickening.

3. 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.

4. Which type of medication helps to reduce the workload on the heart by slowing down the heart rate?

• A. Beta-blocker
• B. Calcium channel blocker
• C. Diuretic
• D. ACE inhibitor

Correct answer: A

Rationale: Beta-blockers are medications that work by blocking the action of hormones like adrenaline, thereby reducing the heart rate and the workload on the heart. This makes them effective in managing high blood pressure and various heart conditions. Calcium channel blockers work by relaxing blood vessels and reducing the heart's workload, but they do not primarily slow down the heart rate. Diuretics help the body get rid of excess salt and water by increasing urine production, which can lower blood pressure but not by slowing down the heart rate. ACE inhibitors work by relaxing blood vessels, not by directly affecting heart rate.

5. What is a condition where the heart muscle becomes abnormally enlarged, thickened, or stiffened, often leading to heart failure?

• A. Cardiomyopathy
• B. Pericarditis
• C. Aortic stenosis
• D. Mitral valve prolapse

Correct answer: A

Rationale: Cardiomyopathy is the correct answer. It is a condition characterized by the abnormal enlargement, thickening, or stiffening of the heart muscle, which can lead to heart failure. Pericarditis (choice B) is inflammation of the pericardium, the sac surrounding the heart, not directly related to heart muscle enlargement. Aortic stenosis (choice C) is the narrowing of the aortic valve opening, affecting blood flow from the heart, but not directly related to heart muscle enlargement. Mitral valve prolapse (choice D) is a condition where the valve between the left atrium and left ventricle doesn't close properly, causing blood to leak backward, and is not directly related to heart muscle enlargement.

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