Cardiovascular System Practice Exam

Correct Answer: A

Rationale: The correct answer is A: Endocardium, Myocardium, Epicardium. The heart consists of three main layers: the endocardium, which lines the inner chambers of the heart; the myocardium, the middle layer responsible for the heart's pumping action; and the epicardium, the outermost layer that protects the heart. Choices B, C, and D are incorrect as they do not list the heart's layers in the correct order or combination.

Correct Answer: A

Rationale: The correct answer is A, systole. Systole is the phase of the cardiac cycle when the heart contracts and pumps blood out of the chambers. During diastole (choice B), the heart relaxes and fills with blood, contrasting with systole. Contractility (choice C) refers to the ability of the heart to contract effectively. Afterload (choice D) is the pressure the heart must work against to eject blood during systole.

Correct Answer: A

Rationale: The correct answer is to monitor heart rate and rhythm when a client is receiving intravenous dopamine. Dopamine is known to potentially cause arrhythmias, making this assessment crucial. While monitoring blood pressure, respiratory rate, and oxygen saturation are important nursing assessments, they are not the most critical when dopamine is being administered.

Correct Answer: A

Rationale: The correct answer is A, myocardial infarction. A myocardial infarction, commonly known as a heart attack, occurs when the blood supply to part of the heart muscle is blocked, often by a blood clot. Choices B, C, and D are incorrect because arrhythmia refers to an irregular heartbeat, stroke involves the interruption of blood flow to the brain, and an aneurysm is a bulge in a blood vessel.

Correct Answer: A

Rationale: The correct answer is A: Preload. Preload is the degree of myocardial fiber stretch before contraction, influenced by the volume of blood returning to the heart. This parameter is related to the amount of blood in the ventricles at the end of diastole. Choice B, Afterload, refers to the pressure or resistance that the ventricles must overcome to eject blood. Choice C, Contractility, is the intrinsic ability of the heart muscle to contract. Choice D, Ejection fraction, is the percentage of blood pumped out of the ventricles with each contraction.