Acute Myocardial Infarction, Atherosclerosis

1. A 55-year-old Hispanic male presents with lower back pain. Physical examination reveals an obese man with BP of 160/110 mm Hg; he has moderately limited range of motion of the back. Arteriography of the patient's abdominal aorta is shown for your evaluation below. Which of the following is the most likely underlying cause for aortic dilation in the patient?

Atherosclerosis

Cystic medial necrosis

Fibrinoid necrosis

Medial degeneration

The most likely underlying cause for aortic dilation in this patient is atherosclerosis. Atherosclerosis is a condition characterized by the buildup of plaque in the arteries, leading to narrowing and stiffening of the vessel walls. In this case, the patient's obesity and hypertension are risk factors for the development of atherosclerosis. The arteriography of the patient's abdominal aorta would likely show the presence of plaques or blockages, which could lead to dilation of the aorta. Cystic medial necrosis, fibrinoid necrosis, and medial degeneration are not typically associated with aortic dilation caused by atherosclerosis.

Explanation

The most likely underlying cause for aortic dilation in this patient is atherosclerosis. Atherosclerosis is a condition characterized by the buildup of plaque in the arteries, leading to narrowing and stiffening of the vessel walls. In this case, the patient's obesity and hypertension are risk factors for the development of atherosclerosis. The arteriography of the patient's abdominal aorta would likely show the presence of plaques or blockages, which could lead to dilation of the aorta. Cystic medial necrosis, fibrinoid necrosis, and medial degeneration are not typically associated with aortic dilation caused by atherosclerosis.

2. A 58 year old female experienced the onset of severe chest pain. An EKG demonstrated changes consistent with an acute myocardial infarction. There was significant elevation of CK-MB, LDH enzymes and Troponin I, in serum. The increase in serum enzyme levels in the serum results from which of the following changes in the myocardial fibers?

Defects in the cell membrane

Clumping of nuclear chromatin

Swelling of the mitochondria

Autophagy by lysosomes

Detachment of ribososmes

Irreversible cell injury is associated with loss of membrane integrity. This allows intracellular enzymes to leak into theserum.
All other morphologic changes listed are associated with reversible cell injury, in which the cell membrane remains intact.

Explanation

Irreversible cell injury is associated with loss of membrane integrity. This allows intracellular enzymes to leak into theserum.
All other morphologic changes listed are associated with reversible cell injury, in which the cell membrane remains intact.

3. The pathology seen in this heart is most likely associated with:

Viral Infection

Systemic Lupus Erythematosus

Tuberculosis

Acute myocardial infarction

Tumor invasion

Notice the fibrinous material sticking to pericardium

Fibrinous Pericarditis:

"Sticky" adherent fibrin strands on surface
Fibrin rich exudate
Caused by:
*Acute myocardial infarction
Uremia (uremic pericarditis) - renal failure
**Post-pericardotomy syndrome -> after coronary artery bypass graft surgery
*Dressler's syndrome

Explanation

Notice the fibrinous material sticking to pericardium

Fibrinous Pericarditis:

"Sticky" adherent fibrin strands on surface
Fibrin rich exudate
Caused by:
*Acute myocardial infarction
Uremia (uremic pericarditis) - renal failure
**Post-pericardotomy syndrome -> after coronary artery bypass graft surgery
*Dressler's syndrome

4. A 67-year-old Hispanic male is found dead in his house. Autopsy reveals hemopericardium due to ventricular wall rupture. How long before his death did the man probably have a myocardial infarction?

< 1 day

1 – 3 days

4 – 7 days

7 – 14 days

14 – 28 days

The presence of hemopericardium due to ventricular wall rupture suggests that the individual likely experienced a myocardial infarction (heart attack) before his death. It takes approximately 4-7 days for a ventricular wall rupture to occur following a myocardial infarction. Therefore, the man probably had a myocardial infarction 4-7 days before his death.

Explanation

The presence of hemopericardium due to ventricular wall rupture suggests that the individual likely experienced a myocardial infarction (heart attack) before his death. It takes approximately 4-7 days for a ventricular wall rupture to occur following a myocardial infarction. Therefore, the man probably had a myocardial infarction 4-7 days before his death.

5. A 65-year-old male recovers from an anterior MI with no complications. An echocardiogram is obtained prior to discharge. What problem is the test is most likely to show?

Ventricular rupture

Constrictive pericarditis

Increased ejection fraction

Severe mitral regurgitation

Ventricular dyskinesia

An echocardiogram is a test that uses sound waves to create images of the heart. It is commonly used to evaluate the structure and function of the heart. In this case, the 65-year-old male has recovered from an anterior myocardial infarction (MI) with no complications. Ventricular dyskinesia refers to abnormal movement of the ventricular wall during contraction. It can occur after a myocardial infarction and is characterized by areas of the ventricular wall that do not move normally. Therefore, an echocardiogram is most likely to show ventricular dyskinesia in this patient.

Explanation

An echocardiogram is a test that uses sound waves to create images of the heart. It is commonly used to evaluate the structure and function of the heart. In this case, the 65-year-old male has recovered from an anterior myocardial infarction (MI) with no complications. Ventricular dyskinesia refers to abnormal movement of the ventricular wall during contraction. It can occur after a myocardial infarction and is characterized by areas of the ventricular wall that do not move normally. Therefore, an echocardiogram is most likely to show ventricular dyskinesia in this patient.

6. Postmortem examination of a patient who died of a confirmed acute myocardial infarction reveals the cardiac changes shown in the image below. What is the most likely "age" of myocardial infarction in this patient?

24 – 72 hours

12 – 24 hours

< 12 hours

4 – 7 days

Explanation

7. A 45-year-old man had a myocardial infarction (MI) 4 days ago and is recovering in the cardiac intensive care unit. Which complication is he MOST AT RISK for developing at this time?

Cardiac aneurysm

Hemopericardium

Atrial myxoma

Mural thrombus

Nutmeg liver

Hemopericardium refers to blood in the pericardial sac of the heart. It is clinically similar to a pericardial effusion, and, depending on the volume and rapidity with which it develops, may cause cardiac tamponade.

The condition can be caused by full-thickness necrosis (death) of the myocardium (heart muscle) after myocardial infarction, as well as trauma, and in patients receiving anticoagulants. Other causes include ruptured aneurysm of sinus of Valsalva and other aneurysms of the aortic arch.

Explanation

Hemopericardium refers to blood in the pericardial sac of the heart. It is clinically similar to a pericardial effusion, and, depending on the volume and rapidity with which it develops, may cause cardiac tamponade.

The condition can be caused by full-thickness necrosis (death) of the myocardium (heart muscle) after myocardial infarction, as well as trauma, and in patients receiving anticoagulants. Other causes include ruptured aneurysm of sinus of Valsalva and other aneurysms of the aortic arch.

8. The pathology associated with this heart is most likely due to:

Familial Hyperlipidemia

Infection

Acute Myocardial infarction

Dialted cardiomyopathy

Cheeseburgeremia

Purulent (Suppurative) Pericarditis

Thick yellow effusion (pus)
Inflammatory exudate
Caused by:
Infection

Explanation

Purulent (Suppurative) Pericarditis

Thick yellow effusion (pus)
Inflammatory exudate
Caused by:
Infection

9. A 56 year old man suffered a myocardial infarction 7 days ago and is recovering in the intensive care unit. If he were to die suddenly at this time, what are the principle microscopic changes you would expect to see in his heart tissue?

Focal coagulative necrosis of myocytes

Abundant cellular debris and neutrophil infiltration

Exuberant macrophage reaction with phagocytosis

Fibrosis and scar tissue

Fibroblast proliferation

Explanation

10. The pathology associated with this heart tissue is:

Lyme disease

Acute myocardial infarction

Myomatous tumor

Chagas

Rheumatic fever

Eosinophilic Myocarditis

Drug reaction (hypersensitivity)
antibiotics, chemotherapeutics
typically have a rash or other immune response
Chagas disease (protozoal infection)
Trypanosoma cruzi
"Kissing bug"

Explanation

Eosinophilic Myocarditis

Drug reaction (hypersensitivity)
antibiotics, chemotherapeutics
typically have a rash or other immune response
Chagas disease (protozoal infection)
Trypanosoma cruzi
"Kissing bug"