Inferior MI

This is part of: Myocardial Infarction

ST elevation in II, III and aVF

This part of the heart muscle lies on the diaphragm and is supplied of blood bij the right coronary artery (RCA) in 80% of patients. In the remaing 20% the inferior wall is supplied by the ramus circumflexus(RCX).

An occlusion of the RCA can be distinguished of a RCX occulusion on the ECG:[1]

Distal RCA occlusion (sens 90%, spec 71%)

• ST segment elevation in III higher than ST segment elevation in II ("the highest elevation points at the culprit")and
• ST segment depression in I, AVL, or both (>1 mm)

Proximal RCA occlusion (sens 79%, spec 100%)

• Additional ST segment elevation in V1, V4R or both

RCX occlusion (sens 83%, spec 96%)

• ST segment elevation in I, AVL, V5, and V6 and
• ST segment depression in V1, V2, and V3

Examples

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  A typical example of an inferior wall infarction.]]

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  Inferior-posterior MI due to RCA occlusion

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  Inferior MI due to RCA occlusion

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  Inferior MI due to RCX occlusion

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  Posterior-lateral MI due to RCX occlusion

References

1. Zimetbaum PJ and Josephson ME. Use of the electrocardiogram in acute myocardial infarction. N Engl J Med. 2003 Mar 6;348(10):933-40. DOI:10.1056/NEJMra022700 |