Okay my gut is bringing me back to pulmonary function i.e. pulmonary hypertension/PE. Some of the highlighted changes in the ECG I think supports this differential - prominent S wave and lead I, invertedT lead III. TallR in VI. I will go out on a limb and suggest aRV MI.
So did you spin up the Cath Lab in time? I'm just guessing this patient dodged the bullet thanks to your attention and clear dDx
