Where is the impulse from the SA node delayed, enabling atrial contraction to complete before the ventricles are stimulated and contract?
- A. AV node
- B. Bundle of His
- C. SA node
- D. Aorta
Correct Answer: A
Rationale: The impulse from the SA node is delayed at the AV node to allow time for the atria to contract before the ventricles. The AV node acts as a gatekeeper, slowing down the electrical signal before transmitting it to the Bundle of His, which then conducts the signal to the ventricles. This delay ensures proper coordination between atrial and ventricular contractions. Choices C and D are incorrect as the SA node does not delay its own impulse, and the aorta is not involved in the conduction system.
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Which chronic condition is characterized by abnormally thickened heart muscle, making it harder for the heart to pump blood efficiently?
- A. Hypertrophic cardiomyopathy
- B. Dilated cardiomyopathy
- C. Restrictive cardiomyopathy
- D. Ventricular hypertrophy
Correct Answer: A
Rationale: Rationale:
1. Hypertrophic cardiomyopathy (HCM) is characterized by thickening of the heart muscle.
2. The thickening reduces the heart's ability to pump blood efficiently.
3. This leads to symptoms like shortness of breath, chest pain, and fatigue.
4. HCM is a genetic condition that affects the heart's structure.
5. Dilated cardiomyopathy involves the heart becoming enlarged, not thickened.
6. Restrictive cardiomyopathy refers to stiffening of the heart muscle.
7. Ventricular hypertrophy is a general term for thickening of the heart's chambers, not the muscle itself.
Summary:
A is correct as HCM matches the description provided. B, C, and D do not align with the specific characteristics of abnormally thickened heart muscle seen in HCM.
A patient who underwent a percutaneous, transluminal coronary angioplasty four weeks ago has a subsequent ejection fraction of 30%. The patient returns for a follow-up visit. Examination reveals lungs that are clear on auscultation and slight pedal edema. The patient's medications are digoxin (Lanoxin), furosemide (Lasix), enalapril maleate (Vasotec), and aspirin. The patient reports a 5 lb (2.27 kg) weight gain over the past two days. The cardiac-vascular nurse's initial action is to:
- A. document the weight and reassess the patient at the next session.
- B. inquire about the patient's medication compliance.
- C. notify the patient's physician.
- D. review the patient's most recent nuclear scan.
Correct Answer: B
Rationale: Weight gain and pedal edema suggest fluid retention, so assessing medication compliance is essential.
Which type of heart disease involves the stiffening of the heart muscle, reducing its ability to relax and fill with blood?
- A. Restrictive cardiomyopathy
- B. Hypertrophic cardiomyopathy
- C. Dilated cardiomyopathy
- D. Ventricular hypertrophy
Correct Answer: A
Rationale: The correct answer is A: Restrictive cardiomyopathy. This type of heart disease involves the stiffening of the heart muscle, leading to decreased ability to relax and fill with blood. Restrictive cardiomyopathy is characterized by abnormal stiffening of the heart muscle, impairing its ability to properly expand and contract during the cardiac cycle. This results in reduced filling of the heart chambers, leading to symptoms of heart failure.
Choice B: Hypertrophic cardiomyopathy involves thickening of the heart muscle, not stiffening.
Choice C: Dilated cardiomyopathy involves enlargement and weakening of the heart chambers, not stiffening.
Choice D: Ventricular hypertrophy is a general term for thickening of the heart muscle, not specific to stiffness.
What is a surgical procedure to create an opening in the windpipe to assist with breathing?
- A. Tracheostomy
- B. Lobectomy
- C. Thoracotomy
- D. Pleurodesis
Correct Answer: A
Rationale: The correct answer is A: Tracheostomy. This surgical procedure involves creating an opening in the windpipe to assist with breathing by bypassing any obstructions in the upper airway. It is commonly performed in cases of severe respiratory distress or when a patient requires long-term mechanical ventilation.
Choice B: Lobectomy involves surgical removal of a lobe of the lung and does not directly relate to creating an opening in the windpipe for breathing assistance.
Choice C: Thoracotomy is a surgical incision into the chest wall but is not specifically related to creating an opening in the windpipe.
Choice D: Pleurodesis is a procedure to treat recurrent pleural effusion by creating adhesions between the layers of the pleura but does not involve creating an opening in the windpipe.
Which term describes a type of abnormal heart rhythm characterized by rapid and irregular beating of the atria?
- A. Atrial fibrillation
- B. Ventricular fibrillation
- C. Atrial flutter
- D. Sinus tachycardia
Correct Answer: A
Rationale: A: Atrial fibrillation is the correct answer as it is characterized by rapid and irregular beating of the atria due to disorganized electrical signals. This leads to inefficient pumping of blood and increases the risk of blood clots.
B: Ventricular fibrillation is incorrect as it refers to rapid, irregular beating of the ventricles, which is life-threatening and requires immediate medical intervention.
C: Atrial flutter is incorrect as it is characterized by a rapid but regular beating of the atria, different from the irregular pattern seen in atrial fibrillation.
D: Sinus tachycardia is incorrect as it is a normal response to stress, exercise, or excitement, characterized by a fast but regular heartbeat originating from the sinus node in the heart.