Massive Precordial ST Elevation. What is it?

This case comes from my book, The ECG in Acute MI:

A male in his 70’s had a cardiac arrest and was successfully defibrillated.  Below is a 12-lead ECG.    

What do you think of this ECG?  What do you think the angiogram showed? 

Due to the obvious ST elevation, he was given tPA (it was a small rural hospital) and the ST elevation quickly resolved.  The patient had bradycardia, heart block, and hypotension. He was intubated, externally paced, and started on pressors.  There was no pulmonary edema.  What is going on?  See below for answer.















This appears to be a right sided ECG, as the R-waves in I and aVL are not present in V5 and V6 (sorry, I don't have the left sided one).

There is an S-wave in lead I and very large R-waves in V1R to V3R.  As there is an rSR' in precordial leads, is this right bundle branch block?  This is a bit uncertain because lead I appears to have normal QRS duration, but V4R to V6R appear wide.  In any case, is there right  ventricular hypertrophy?  It is difficult to make a diagnosis of right ventricular hypertrophy in the presence of RBBB because both cause an S-wave in lead I and a large R'-wave in V1.  However, in this case the R'-wave in V1-V3 is far larger than with a normal RBBB.  In any case, the R' wave is very large, diagnostic of RV hypertrophy.

ST elevation: There is ST elevation in II, III, aVF with reciprocal ST depression in aVL (inferior STEMI), and ST elevation from V1R to V6R (right ventricular STEMI).  Angiogram showed subtotal occlusion of proximal RCA.  Wedge pressure was 18 (low for a patient in cardiogenic shock).  Echocardiogram showed severe RV hypertrophy with very poor RV function and good LV function but poor LV filling pressures.  It was later discovered that the patient had a history of pulmonary fibrosis and pumonary hypertension.  ST elevation was due to right ventricular STEMI in the setting of severe right ventricular hypertrophy.