ATI RN
Cardiovascular System Exam
1. What does the PR interval measure?
- A. Time it takes for the electrical impulse to travel from the atria to the ventricles
- B. Measurement of ventricular depolarization
- C. Duration of ventricular repolarization
- D. Segment representing the time between ventricular depolarization and repolarization
Correct answer: A
Rationale: The PR interval measures the time it takes for the electrical impulse to travel from the atria to the ventricles. It is crucial in diagnosing heart rhythm disorders, as abnormalities in this interval can indicate conduction abnormalities between the atria and ventricles. Choices B, C, and D are incorrect. The QRS complex represents ventricular depolarization, the QT interval represents the duration of ventricular repolarization, and the ST segment represents the time between ventricular depolarization and repolarization.
2. What is the term for the amount of blood ejected by the left ventricle into the aorta per beat, determined by preload, contractility, and afterload?
- A. Stroke volume
- B. Cardiac output
- C. End-diastolic volume
- D. Ejection fraction
Correct answer: A
Rationale: The correct answer is A: Stroke volume. Stroke volume refers to the volume of blood ejected by the left ventricle during each heartbeat. This is determined by preload (the degree of stretch of the cardiac muscle fibers at the end of diastole), contractility (the force of myocardial contraction), and afterload (the pressure or resistance that the ventricle must overcome to eject blood). Choice B, Cardiac output, is the volume of blood pumped by the heart per minute and is calculated by multiplying the heart rate by the stroke volume. Choice C, End-diastolic volume, is the volume of blood in the ventricle at the end of diastole before contraction. Choice D, Ejection fraction, is the proportion of blood pumped out of the ventricle with each contraction, calculated by dividing the stroke volume by the end-diastolic volume.
3. Which surgical procedure involves removing a portion of the lung?
- A. Lobectomy
- B. Pneumonectomy
- C. Tracheostomy
- D. Bronchoscopy
Correct answer: A
Rationale: A lobectomy is the surgical removal of a lobe of the lung. This procedure is commonly performed to treat conditions like lung cancer or severe lung diseases. Pneumonectomy involves removing an entire lung, making it incorrect. Tracheostomy is a surgical procedure to create an opening in the windpipe, not involving lung tissue removal. Bronchoscopy is a diagnostic procedure that allows visualization of the airways using a thin, flexible tube with a camera, not involving lung tissue removal.
4. What test uses sound waves to create images of the heart and assess its structure and function?
- A. Echocardiogram
- B. MRI
- C. CT scan
- D. X-ray
Correct answer: A
Rationale: An echocardiogram is the correct answer because it is a test specifically designed to use sound waves to create images of the heart, allowing healthcare providers to assess both its structure and function, as well as to detect any abnormalities. MRI (Choice B), CT scan (Choice C), and X-ray (Choice D) do not primarily use sound waves for imaging the heart; therefore, they are not the most appropriate choices for this scenario.
5. Which medication relaxes the muscles around the airways, making it easier to breathe?
- A. Bronchodilator
- B. Corticosteroid
- C. Antihistamine
- D. Mucolytic
Correct answer: A
Rationale: The correct answer is A, Bronchodilator. Bronchodilators are medications that relax the muscles surrounding the airways, which helps to open them and makes breathing easier. Corticosteroids (choice B) work by reducing inflammation, antihistamines (choice C) are used to manage allergies, and mucolytics (choice D) help to break down and thin mucus in the airways.
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