A STEMI patient arrives late after 48 hours with chest pain .There is persistent ST elevation.
What is the likely mechanism of this chest pain ?
- Index infarct pain continuing . . .
- Post infarct Angina-IRA territory
- Re-infarction following intermittent re-perfusion and re-occlusion
- Remote ischemia from a branch of IRA
- Ischemia from a possible non IRA lesion in a multivessel CAD
If this patient comes to a non PCI eligible centre. Will you lyse him ?
If post infarct angina is unstable angina . Isn’t thrombolysis contraindicated in UA ?
How to differentiate Post Infarct Angina from Re-Infarction ?
A very tricky issue indeed.
Unless fresh ST elevation with fresh enzyme peak is documented these entities cannot be differentiated.
(Even fresh ST elevation can be related to infarct expansion ,stretch or early acute remodeling.Fresh enzyme release or new peak may not represent new infarct always .It can be due to intermittent re-perfusion of IRA .It may simply represent a enzyme flush from the index infarct zone)
What is the practical , realistic , (Unscientific !) solution ?
Why break our head ? Never bother to differentiate PIA from Reinfarction etc . Let it be any thing . Do a emergency CAG .Stent whichever lesion looks good for the same . Of course , make sure he has enough insurance coverage .
Dr.S.Venkatesan MD 