VS:
BP: 140/90, P: 62, R: 16, Sp02: 99%
EXAM:
The patient is slightly diaphoretic and appears uncomfortable. A 12 lead ECG is obtained.
ACTIONS:Do you activate the cath lab?
Do you administer NTG?
12 LEAD ECG:
12 LEAD ECG CASE DISCUSSION:
The ECG shows a first degree heart block. ST segment elevations are apparent in Leads II, III, and aVF. Reciprocal changes are present in Leads I and aVL. ST segment changes are present in the septal leads of V3 to V4. The diagnosis of a posterior wall myocardial infarction is less likely given (1) the absence of tall R waves and (2) The absence of ST depression in leads V1-V3. However, anytime anterior precordial ST depression appears concurrently with an inferior wall MI, you should consider the diagnosis of a posterior wall infarction. Recall that the posterior descending coronary artery comes from the right coronary artery. It is wise to be cautious with nitroglycerin since this infarction may involve portions of the right ventricle. Have IV access established and consider right sided chest leads if there is concern for a right ventricular infarction. This patient went emergently to the cardiac catheterization lab and was found to have a completely (100%) occluded right coronary artery. Finally, conduction delays and heart blocks are consistent with ischemia of the sinoatrial node and the conduction system.
12 LEAD ECG INTERPRETATION:
Inferior wall ST elevation myocardial infarction.
