Cardio: Ischemic Heart Disease and MI Flashcards
1
Q
- Secondary to atherosclerosis; exertional chest pain in classic distribution
- Usually w/ ST depression on ECG
- Resolves w/ rest
A
Stable Angina
2
Q
- Occurs at rest, secondary to Coranary artery spasm
- Transient ST elevation
- A/w tobacco, cocaine, and triptans
- Treat w/ Ca2+ channel blockers, Nitrates, and Smoking cessation
A
Variant Angina (Prinzmetal)
3
Q
- Thrombosis with incomplete coronary artery occlusion
- ST depression
- Increasing frequency and intensity of chest pain
A
Unstable Angina
4
Q
- Distal to Coronary stenosis, vessels are maximally dilated at baseline
- Administration of vasodilators (dipyridamole, regadenoson) dilates normal vessels and shunts blood toward well-perfused areas
→ ↓ flow and ischemia in the poststenotic region - Principle behind pharmacologic stress tests
A
Coronary Steal Syndrome
5
Q
- Most often Acute Thrombosis due to Coronary Artery Atherosclerosis w/ complete occlusion of Coronary Artery and Myocyte necrosis
- Cardiac biomarkers are diagnostic
- Transmural, ECG will show ST elevations
- Subendocardial, ECG will show ST depression
A
Myocardial Infarction
6
Q
Evolution of MI: 0 - 4 hr
A
- Gross: None
- Microscope: None
- Complications:
- Arrhythmia, HF, Cardiogenic shock, Death
7
Q
Evolution of MI: 4 - 12 hr
A
- Gross:
- Occluded artery → Dark mottling w/ tetrazolium stain
- Microscope:
- Early coagulative necrosis, release of necrotic cell contents into blood; edema, hemorrhage, wavy fibers
- Complications:
- Arrhythmia, HF, Cardiogenic shock, Death
8
Q
Evolution of MI: 12 - 24 hr
A
- Gross: Occluded Coronary Artery
- Microscope:
- Neutrophil migration starts
- Reperfusion injury may cause contraction bands due to free radical damage
- Complications:
- Arrhythmia, HF, Cardiogenic shock, Death
9
Q
Evolution of MI: 1 - 3 days
A
- Gross: Hyperemia
- Microscope:
- Extensive Coagulative necrosis
- Tissue surrounding infarct shows acute inflammation w/ Neutrophils
- Complications: Fibrinous pericarditis
10
Q
Evolution of MI: 3 - 14 days
A
- Gross:
- Hyperemic border; central yellow-brown softening - maximally yellow and soft by 10 days
- Microscope:
- Macrophages, then granulation tissue at margins
- Compications:
- Free wall rupture → tamponade; papillary muscle rupture → Mitral regurgitation; interventricular septal rupture due to macrophage-mediated structural degradation
- LV Pseudoaneurysm (Mural thrombus “plugs” hole in myocardium → “time bomb”
11
Q
Evolution of MI: 2 weeks to several months
A
- Gross: Recanalized artery w/ Gray-white scarring
- Microscope: Contracted scar complete
- Complications:
- Dressler syndrome, HF, Arrhythmias, True ventricular aneurysm (outward bulge during contraction), “Dyskinesia”
12
Q
Cardiac Troponin I
A
- Rises after 4 hrs and is ↑ for 7 - 10 days
- More specific than other protein markers
13
Q
CK-MB
A
- Predominantly found in myocardium but can also be released by skeletal muscle
- Useful in diagnosing Reinfarction following Acute MI because levels return to normal after 48 hrs
14
Q
Q waves: V1 - V4
A
Anterior wall infarct - LAD
15
Q
Q waves: V1 - V2
A
Anteroseptal infarct - LAD
