PATHOLOGY LAB 1 - 

PATHOLOGY AND PATHOPHYSIOLOGY OF ISCHEMIC HEART DISEASE

J.P. Veinot M.D. FRCPC

For another excellent tutorial on ischemic heart disease go to library.med.utah.edu/WebPath/TUTORIAL/MYOCARD/MYOCARD.html

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Students will  examine the specimens with the instructor. The group will review the angiograms and x-rays with the instructor.

For answers to questions press here answers

1- THE AORTA 

These specimens are 'plastinated' to make their handling easier. The specimens, of course, do not have the normal soft texture of real tissue. The other specimens are fixed in formalin, and again some of the normal texture has been lost as a result.

What happens to tissues when we fix them and why do we bother (in general terms)? Orient the tissue. Some of the aortas have been opened posteriorly during the autopsy.

a. Identify and name the major aortic branches. Picture of external aorta with branches

b. Identify the atherosclerotic plaques. Where are they concentrated, and why?  Aorta with fatty streaks ; Complicated aortic atherosclerosis

c. The aorta is a convenient site, because of its size, to visualize atherosclerotic plaques, and to imagine how they might cause the patient's disease. List ways these plaques might become clinically important, and explain the pathophysiologic mechanism of each. Atherosclerosis high power view ; Atherosclerotic plaque in coronary artery

d. What kind of artery is the aorta?... renal?... coronary? Do you think this matters?

 

2- Heart to Display Normal Coronary Artery Distribution:

Orient the heart.

a. Which surface is anterior, and which posterior?

b. Trace the course of the left main, the left anterior descending (LAD), the left circumflex (LCX) and right (RCA) coronary arteries (consult the diagram for help if necessary). Diagram of coronary artery distribution

c. Coronary angiograms (see example) are x-ray images prepared when dye is injected into the coronary arteries. What does this study show? What might be some of their limitations? Can you think of additional imaging techniques to visualize the arterial lesions? d. What other cardiac structures are each of the coronary arteries closely related to? Angiogram example

e. Some of the epicardial adipose tissue has been removed to better display the arteries. What is the adipose tissue's function during life?

f. Where do coronary artery atherosclerotic plaques preferentially occur in the coronary artery tree?

g. What can be done clinically when a patient presents with symptoms referable to atherosclerotic coronary artery plaque?

 

3- Heart with Infarct(s)-1

This heart is from an autopsy. Myocardial infarct ; Myocardial infarct ; Myocardial infarct complication

a. Create a mock clinical history which would explain the pathologic findings, including probable patient signs and symptoms. Consider whether the heart shows any other pathology (eg. hypertrophy, valve disease), where the infarct is located, how big and how deep the infarct is, how old the infarct is - all of these things should be reflected in the mock history of the patient.

b. The angiogram was done on the heart after it was removed from the patient. Do you see the lesion? How might a post mortem angiogram be useful?

 

4- Heart With Infarct(s)-2

This heart is a surgical (transplant) specimen. The patient had this heart removed and replaced with a healthy donor heart. The patient is now alive and well.

Myocardial infarct
Myocardial infarct

a. Describe the heart, including site, depth, age and any complications of the infarct(s). Describe the likely coronary artery pathology in the background. Describe the size and weight of the heart and the size of the left and right ventricular cavities, if these are abnormal, why are they so?

b. In general terms, what is the main indication for cardiac transplant?

c. Why is this heart cut off just above the level of the heart valves?

d. When coronary artery atherosclerosis causes heart failure, does it always do so by producing myocardial infarcts?

e. When a patient receives a new heart is it exactly like their old one? What are the differences?

 

5- Heart With Infarct Complication -1

a. What complication of infarct is demonstrated here? How common is it? MI with complication ; AMI complication

b. When in the time course of an infarct is this complication likely to occur?

c. What sort of patient, heart and infarct do you think this complication is more likely to be seen in?

d. How does this complication cause patient death, and what is the pathophysiology? What can be done, if anything, to treat it?

e. List other major infarct complications, in their frequency of incidence. What complication does the x-ray show? What is the study?

 

6- Infarct Complication - 2

a. What complication of infarct is illustrated here? Complication of MI

b. How would this patient have presented clinically? Symptoms and signs?

c. What clinical investigations might have suggested or confirmed the presence of this complication?

d. This is a surgical specimen from a patient with this complication. What operation did the surgeons perform? AMI complication

e. This complication of infarct was a treatable one. Which of the others in your list of infarct complications is also treatable? Generally, what is the treatment for each? Infarct complication