Peer tutorial Flashcards
What are the two major patterns of MI?
- Transmural (usually STEMI)
2. Subendocardial (usually NSTEMI)
What conditions are characterised as acute coronary syndromes and which ones are characterised as chronic coronary syndrome?
ACS: 1. Unstable angina 2. Myocardial infarction 3. Sudden cardiac death CCS: 1. Stable angina 2. Chronic myocardial ischemia
Histological features 1 day post MI
Irreversible injury: Key: - Eosinophilic - Hemorrhagic, therefore RBCs Other: - Coagulative necrosis - Breakdown of nuclei - Disarray - Not many inflammatory cells
Histological features 3-7 days post MI
Acute inflammation:
- Neutrophils
Histological features 1-2 wks post MI
Early granulation tissue:
- Complete disarray
- Fibroblasts (main cell). These won’t appear earlier.
- Macrophages
- Capillaries
- Lymphocytes
Histological features 6-8 wks post MI
Scar tissue:
- No structure, just scar tissue
- Scattered fibroblasts
- Eosinophilic
Gross pathology of MI 3-10days post event
- Pale (coagulative necrosis)
- Thin (after some time)
- Fibrous
Supply of the LAD
- Anterior 2/3 of septum
- Anterior wall of LV
Supply of left circumflex
- Lateral wall of LV
Supply of right coronary artery
- SA/AV node
- Posterior 1/3 of septum
- Right ventricle
Complications of MI
Immediate: 1. Arrhythmias 2. Acute cardiac failure 3. Cardiogenic shock Days: 1. Mechanical complications (papillary muscle or wall rupture, acquired VSD) 2. Infarct expansion 3. Pericarditis 4. Arrhytmias 5. Mural thrombus formation 6. Progressive cardiac failure Weeks-months 1. LV aneurysm and thombus formation 2. Chronic cardiac failure - this is KEY 3. Arrhythmias (hear block, sick sinus syndrome)
Complications of MI
Immediate: 1. Arrhythmias 2. Acute cardiac failure 3. Cardiogenic shock Days: 1. Mechanical complications (papillary muscle or wall rupture, acquired VSD) 2. Infarct expansion 3. Pericarditis 4. Arrhythmias 5. Mural thrombus formation 6. Progressive cardiac failure Weeks-months 1. LV aneurysm and thombus formation 2. Chronic cardiac failure - this is KEY 3. Arrhythmias (hear block, sick sinus syndrome)
Complications of MI
Immediate: 1. Arrhythmias 2. Acute cardiac failure 3. Cardiogenic shock Days: 1. Mechanical complications (papillary muscle or wall rupture, acquired VSD). N.B. Ventricular septal defect. 2. Infarct expansion 3. Pericarditis 4. Arrhythmias 5. Mural thrombus formation 6. Progressive cardiac failure Weeks-months 1. LV aneurysm and thombus formation 2. Chronic cardiac failure - this is KEY 3. Arrhythmias (hear block, sick sinus syndrome) N.B. At all stages there is the possibility of arrhythmia and cardiac failure (acute -> progressive -> chronic)
Most common problem post MI
Chronic ischemic heart disease
Causes of sudden cardiac death
- Fatal tachyarrhythmia (often can be idiopathic). Can be the 1st manifestation of ischemic heart disease
- Acute MI
What is an aneurysm
- Bulge/dilation of lumen in blood vessel wall. Not dissection, because blood still contained in lumen
- Caused by weakening in MEDIA
What is an aneurysm
- Bulge/dilation of lumen in blood vessel wall. Not dissection, because blood still contained in lumen
2 types of true aneursym
- Saccular (one side)
2. Fusiform (both sides)