NU606 | NU606 Advanced Pathophysiology Exam 2
Version 2 | Questions with Correct Answers and
Expert Explanation for Each Question | Regis
1. A patient presents with sudden onset of chest pain, diaphoresis, and nausea. The
ECG shows ST-segment elevation in leads V1-V4. Which coronary artery is most likely
occluded?
A. Right coronary artery
B. Left anterior descending artery
C. Left circumflex artery
D. Posterior descending artery
Correct Answer: B
Expert Explanation: The ST-segment elevation in leads V1 through V4 indicates an
anterior wall myocardial infarction. The left anterior descending (LAD) artery is the
primary vessel responsible for supplying blood to the anterior wall of the left
ventricle. Occlusion of this artery typically results in the ECG patterns observed in
these specific precordial leads.
2. Which compensatory mechanism is activated in response to a decrease in cardiac
output during heart failure?
A. Parasympathetic nervous system activation
,B. Activation of the sympathetic nervous system
C. Inhibition of the renin-angiotensin-aldosterone system
D. Decreased secretion of antidiuretic hormone
Correct Answer: B
Expert Explanation: When cardiac output drops, the body attempts to maintain
perfusion through several compensatory mechanisms. The sympathetic nervous
system is rapidly activated, leading to an increase in heart rate and contractility.
This response is intended to restore blood pressure but can eventually lead to
increased myocardial oxygen demand and further cardiac damage.
3. In the pathogenesis of atherosclerosis, which cells are responsible for the formation
of ‘foam cells’ after ingesting oxidized LDL?
A. Neutrophils
B. Endothelial cells
C. Smooth muscle cells
D. Macrophages
Correct Answer: D
Expert Explanation: Atherosclerosis begins with endothelial injury that allows LDL
to enter the arterial intima. Macrophages migrate to the site of injury and
,phagocytize oxidized LDL particles. Once these macrophages become engorged with
lipids, they are referred to as foam cells, which are a hallmark of early
atherosclerotic plaques.
4. A 65-year-old male with a history of chronic hypertension presents with a tearing
sensation in his chest radiating to his back. What is the most likely pathophysiological
diagnosis?
A. Acute pericarditis
B. Pulmonary embolism
C. Aortic dissection
D. Stable angina
Correct Answer: C
Expert Explanation: Aortic dissection involves a tear in the tunica intima of the
aorta, allowing blood to enter the media layer. The classic presentation is a sharp,
tearing or ripping pain that radiates to the back or between the shoulder blades.
Hypertension is the most significant risk factor for this life-threatening condition
due to the chronic stress placed on the aortic wall.
5. Which valvular disorder is characterized by a mid-systolic click and a late systolic
murmur?
A. Mitral valve prolapse
, B. Aortic stenosis
C. Mitral regurgitation
D. Tricuspid stenosis
Correct Answer: A
Expert Explanation: Mitral valve prolapse (MVP) occurs when the mitral valve
leaflets bulge into the left atrium during systole. This displacement often causes a
characteristic mid-systolic click followed by a murmur if regurgitation is present. It
is the most common valvular abnormality in the United States and is often
asymptomatic.
6. A patient with a history of rheumatic fever presents with dyspnea on exertion and a
low-pitched diastolic rumble at the apex. Which valve is most likely affected?
A. Mitral valve
B. Pulmonary valve
C. Tricuspid valve
D. Aortic valve
Correct Answer: A
Expert Explanation: Mitral stenosis is commonly caused by previous rheumatic
heart disease, which leads to scarring and narrowing of the valve. The narrowing
Version 2 | Questions with Correct Answers and
Expert Explanation for Each Question | Regis
1. A patient presents with sudden onset of chest pain, diaphoresis, and nausea. The
ECG shows ST-segment elevation in leads V1-V4. Which coronary artery is most likely
occluded?
A. Right coronary artery
B. Left anterior descending artery
C. Left circumflex artery
D. Posterior descending artery
Correct Answer: B
Expert Explanation: The ST-segment elevation in leads V1 through V4 indicates an
anterior wall myocardial infarction. The left anterior descending (LAD) artery is the
primary vessel responsible for supplying blood to the anterior wall of the left
ventricle. Occlusion of this artery typically results in the ECG patterns observed in
these specific precordial leads.
2. Which compensatory mechanism is activated in response to a decrease in cardiac
output during heart failure?
A. Parasympathetic nervous system activation
,B. Activation of the sympathetic nervous system
C. Inhibition of the renin-angiotensin-aldosterone system
D. Decreased secretion of antidiuretic hormone
Correct Answer: B
Expert Explanation: When cardiac output drops, the body attempts to maintain
perfusion through several compensatory mechanisms. The sympathetic nervous
system is rapidly activated, leading to an increase in heart rate and contractility.
This response is intended to restore blood pressure but can eventually lead to
increased myocardial oxygen demand and further cardiac damage.
3. In the pathogenesis of atherosclerosis, which cells are responsible for the formation
of ‘foam cells’ after ingesting oxidized LDL?
A. Neutrophils
B. Endothelial cells
C. Smooth muscle cells
D. Macrophages
Correct Answer: D
Expert Explanation: Atherosclerosis begins with endothelial injury that allows LDL
to enter the arterial intima. Macrophages migrate to the site of injury and
,phagocytize oxidized LDL particles. Once these macrophages become engorged with
lipids, they are referred to as foam cells, which are a hallmark of early
atherosclerotic plaques.
4. A 65-year-old male with a history of chronic hypertension presents with a tearing
sensation in his chest radiating to his back. What is the most likely pathophysiological
diagnosis?
A. Acute pericarditis
B. Pulmonary embolism
C. Aortic dissection
D. Stable angina
Correct Answer: C
Expert Explanation: Aortic dissection involves a tear in the tunica intima of the
aorta, allowing blood to enter the media layer. The classic presentation is a sharp,
tearing or ripping pain that radiates to the back or between the shoulder blades.
Hypertension is the most significant risk factor for this life-threatening condition
due to the chronic stress placed on the aortic wall.
5. Which valvular disorder is characterized by a mid-systolic click and a late systolic
murmur?
A. Mitral valve prolapse
, B. Aortic stenosis
C. Mitral regurgitation
D. Tricuspid stenosis
Correct Answer: A
Expert Explanation: Mitral valve prolapse (MVP) occurs when the mitral valve
leaflets bulge into the left atrium during systole. This displacement often causes a
characteristic mid-systolic click followed by a murmur if regurgitation is present. It
is the most common valvular abnormality in the United States and is often
asymptomatic.
6. A patient with a history of rheumatic fever presents with dyspnea on exertion and a
low-pitched diastolic rumble at the apex. Which valve is most likely affected?
A. Mitral valve
B. Pulmonary valve
C. Tricuspid valve
D. Aortic valve
Correct Answer: A
Expert Explanation: Mitral stenosis is commonly caused by previous rheumatic
heart disease, which leads to scarring and narrowing of the valve. The narrowing
