STEMI Without The "STE"

HPI: 57 y/o woman with remote hx of CABG/PCI presents with 2 hrs of 6-10/10 substernal chest tightness and SOB. No recent cardiac events/complaints. Initial troponin is 1.48.

Question:  Is this patient experiencing a STEMI despite the lack of ST elevations ≥1mm?  How would you diagnose this and explain to your cardiology consultants?