Cardiovascular System Exam

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.

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.

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.

Correct Answer: A

Rationale: Thoracentesis is the correct answer. It is a procedure where a needle is inserted into the pleural space to drain fluid, relieving pressure and helping the patient breathe more easily. Bronchoscopy (choice B) is a procedure used to examine the airways, not to drain fluid. An echocardiogram (choice C) is an imaging test to assess the heart's structure and function, not related to draining pleural fluid. A CT scan (choice D) is a cross-sectional imaging test that provides detailed pictures of the inside of the body, not used for draining pleural fluid.

Correct Answer: A

Rationale: Ventricular tachycardia is the correct answer. It is a condition characterized by the heart's electrical system malfunctioning, leading to very fast heartbeats originating from the ventricles. Ventricular tachycardia can be life-threatening as it may progress to ventricular fibrillation, causing cardiac arrest. Atrial fibrillation (choice B) involves rapid, irregular beating of the atria, not the ventricles. Supraventricular tachycardia (choice C) originates above the ventricles and does not involve ventricular malfunction. Bradycardia (choice D) is the opposite of tachycardia, characterized by an abnormally slow heart rate.