ACLS review: Acute Coronary Syndromes Part 5

Anatomic regions

·         I, aVL, V5, V6                              High lateral wall

·        V5, V6                                          Low lateral wall

·         II, III, aVF                                     Inferior wall

·         V1-V4                                          Anterior wall

·         V4R                                             Right ventricle

Coronary anatomy

·         I, aVL, V5, V6                              Circumflex artery

·         II, III, aVF                                     Right coronary artery

·         V1-V4                                          Left anterior descending

·         V4R                                             Right coronary artery

Inferior wall MI

Inferior Wall MI



Inferior ST elevation in II,III, and aVF. 
Anterior ST elevation also in V3 but not in V2 or V4 so this is probably not significant.  Remember, ST elevation has to be in two contiguous leads to be significant for an MI.
The RCA profuses the inferior wall of the left ventricle as well as the right ventricle.  In a patient with an inferior wall MI that becomes extremely hypotensive with either nitroglycerine or even morphine suspect that there may be some right ventricular involvement. This patient will require fluid volume instead.

Anterior wall MI

Anterior Wall MI

Anterior ST elevation in V1-V4.   The anterior wall of the left ventricle is profused by the LAD artery.  An occulsion of the LAD may lead to an infarction of a large amount of muscle mass in the left ventricle and subsequently lead to cardiogenic shock.  The LAD also profuses the intraventricular septum so the patient may exhibit a Mobitz II or complete heart block. 



High Lateral Wall MI

High Lateral Wall MI



High lateral ST elevation is evident in leads I and aVL.   The lateral wall is profused by the left circumflex artery.  In left dominant individuals, the circumflex profuses the SA node (10%) and AV node (45%) as well as the posterior left ventricle.  Infarction at the level of the AV node may lead to a Mobitz I block.

Low Lateral Wall MI

Low Lateral Wall MI





Low lateral ST elevation is observed in leads V5-V6.

Proximal Left Main Occulsion

Global ST elevation in all leads.