Histopathology 6 - Vascular and Cardiac pathology Flashcards
What are the 3 stages of atheroma development?
- Raised lesion
- Soft lipid core
- White fibrous cap
Recall the 7 steps of atheroma pathophsyiology
- Endothelial injury
- LDL enters intima and gets trapped in intimal space
- LDL is converted into oxidised LDL –> inflammation
- Macrophages take up OxLDL via scavenger receptors –> foam cells
- Foam cell apoptosis –> inflammation and cholesterol deposition to form plaque core
- Endothelium expresses more adhesion molecules –> more macrophages and T cells enter plaque
- VSMCs form fibrous cap
What % occlusion of a vessel lumen by atheroma is considered ‘critical stenosis’?
70%
What causes prinzmental angina?
Coronary artery spasm
Which parts of the cardiac muscle are affected by an infarction of the LAD?
Anterior wall of left ventricle, anterior septum and apex
Which parts of the cardiac muscle are affected by an infarction of the RCA?
Posterior wall of left ventricle, posterior septum and posterior wall of right ventricle
Which parts of the cardiac muscle are affected by an infarction of the LCx?
Lateral wall of left ventricle
What are the 4 most important complications of MI?
- Contractile dysfunction (eg cardiogenic shock)
- Arrhythmia
- Myocardial rupture (occurs at day 4-5)
- Pericarditis
What is Dressler’s syndrome?
Pericarditis occuring weeks-months post-MI
What is the average time between MI and myocardial rupture?
4-5 days
What is the prognosis of papillary muscle rupture following MI?
Rubbish - very high mortality
What is the most common cause of sudden cardiac death?
Lethal arrhythmia
What is restrictive cardiomyopathy?
When there is impaired ventricular compliance (contractibility)
Normal size heart but with large atria - may be due to amyloidosis
Recall 3 possible causes of aortic regurgitation
Infective endocarditis
Marfan’s
Ankylosing spondylitis
What is Monckeberg atherosclerosis?
Focal calcification of the media of small-medium sized vessels; no associated inflammation
What histological findings would be found within 6 hours of an MI?
Normal histology and normal CK-MB
What histological findings would be found 6 -24 hours following an MI? (3)
- Loss of nuclei
- Homogenous cytoplasm
- Necrotic cell death
What histological findings would be found 1-4 days following an MI?
Infiltration of polymorphs and macrophages (to clear up debris)
What histological findings would be found 5-10 days following an MI?
Removal of debris
What histological findings would be found 1-2 weeks following an MI?
Granulation tissue
New blood vessels
Myofibroblasts
Collagen synthesis
What histological findings would be found in the months following an MI?
Strengthening, de-cellularising scar tissue
Recall the possible complications of MI
Mnemonic = PACE MAKERED
Papillary muscle dysfunction
Arrhythmia
Ccf
Effusion (pericardial)
Mural thrombus
Aneurism (ventricular)
(K)ontractile dysfunction
Early pericarditis
Rupture of venticular wall
Elevation of ST segment
Dressler’s syndrome
What types of cardiomyopathy can be caused by sarcoidosis?
Dilated and restrictive
Which type of cardiomyopathy is associated with alcohol misuse?
Dilated
