STEMI mimickers Flashcards
1
Q
What are some of the most common STEMI mimickers?
A
- LBBB
- RBBB
- Paced rhythms
- Ventricular escape rhythm
- Pericarditis
- Dissecting aortic aneurysm
- Left ventricular hypertrophy
- Benign early repolarization
- Ventricular aneurysm
2
Q
Explain the physiology behind ECG changes in LBBB
A
- Electrical conduction is blocked through the left bundle branch
- Impulse spreads to the right ventricle via the RBBB and then to the left ventricle via the septum
- Produces tall “R” waves in lateral leads (V5, V6) and deep “S” waves in the right precordial leads (VI-V3)
- Ventricles are activated right to left, rather than simultaneously, which produces “M” shape in lateral leads and “W” in precordial leads (VI)
3
Q
Explain the physiology behind ECG changes in RBBB
A
- Activation of right ventricle is delayed but left ventricle is activated normally
- Early portion of QRS complex is unchanged
- Delayed activation to right ventricle produces a secondary “R” wave in Leads VI-V3, slurred ‘s” waves in lateral leads, and an “M” shaped QRS in VI-V3
- ST segment depression and T wave inversion normal in VI-V3
4
Q
What are the causes of LBBB?
A
- Acute MI
- Aortic stenosis
- Coronary Artery Disease
- HTN
- Digoxin toxicity
- Hyperkalaemia
- Disease of the conduction system
5
Q
What are the causes of RBBB?
A
- Right ventricular hypertrophy/cor pulmonale
- Pulmonary embolis
- Ischemic heart disease
- Myocarditis or cardiomyopathy
- Congenital heart disease
- Disease of the conduction system
6
Q
Notching or slurring J point is an indication of which mimicker?
A
BER
7
Q
T waves with a smaller amplitude than the hyperactive T waves seen in STEMIs are indicative of which mimicker?
A
Ventricular aneurysm
