Correct Answer: A

Rationale: The correct action is to hold the beta blocker and notify the healthcare provider. A heart rate of 50 bpm is already low, and beta blockers can further decrease the heart rate, potentially causing adverse effects like bradycardia or heart block. Administering the beta blocker as ordered (Choice B) can exacerbate the low heart rate. Decreasing the dose of the beta blocker (Choice C) may not be sufficient to address the potential harm. Monitoring the client's heart rate and reassessing in 30 minutes (Choice D) may delay necessary interventions if the heart rate drops further. Therefore, the priority is to hold the medication and seek guidance from the healthcare provider.

Correct Answer: A

Rationale: A stress test, also known as an exercise stress test, evaluates the heart's response to physical stress by monitoring its activity during exercise, typically on a treadmill. This test helps assess the heart's performance, detect coronary artery disease, and evaluate the effectiveness of heart treatments. Echocardiogram (choice B) is an ultrasound of the heart that provides detailed images of the heart's structure and function, but it does not involve physical stress like a stress test. Holter monitor (choice C) is a device for continuously monitoring the heart's rhythm and rate over a period (usually 24-48 hours), not during exercise. CT angiography (choice D) is a diagnostic test that uses X-rays to visualize blood vessels but does not involve physical stress like a stress test.

Correct Answer: A

Rationale: The correct answer is Pneumothorax. Pneumothorax occurs when air or gas accumulates in the pleural space, causing the lung to collapse. This condition can result in symptoms such as chest pain and difficulty breathing. Pulmonary embolism (choice B) is a blockage in one of the pulmonary arteries in the lungs, usually caused by a blood clot. Pleural effusion (choice C) is the accumulation of excess fluid in the pleural space, not air or gas. Atelectasis (choice D) refers to the collapse or closure of a lung resulting in reduced or absent gas exchange.

Correct Answer: A

Rationale: The correct answer is Electrocardiogram (ECG or EKG). An electrocardiogram is a test that measures the electrical activity of the heart and can detect irregularities in heart rhythm. Choices B, C, and D are incorrect because a chest X-ray, MRI, and CT scan do not specifically measure the electrical activity of the heart or detect heart rhythm problems.

Correct Answer: A

Rationale: Valve replacement is the correct answer because it specifically involves surgically replacing a damaged or diseased heart valve with a prosthetic valve to address narrowing or blockage, thereby improving blood flow and heart function. Angioplasty (choice B) is a procedure to widen narrowed or obstructed arteries, typically using a balloon catheter. Stent placement (choice C) involves inserting a mesh tube to support a weakened artery. Coronary bypass surgery (choice D) is a procedure to create new routes for blood flow to the heart muscle by bypassing blocked arteries.