How often you assess the success of Primary PCI with degree of ST segment regression or resolution ?
I posed this query to a freshly hatched , Intelligent and energetic cardiologist in an upscale dedicated heart care center.
He said, “No, we don’t .We always go with TIMI flow in IRA .TIMI 3 flow with less than 30% narrowing of IRA is success, that’s it ! He continued ,very often ,we don’t even Insist to take serial ECGs after the procedure . . . forget about analysing ST segment ! His body language seemed to suggest, he didn’t expect such a question (Silly !) from me , talking about ECG in this era of hyper Interventionism where we literally live within the coronary artery !
What a grave error in coronary cognition ? . . . thats commited day in day out of cath lab all over the globe !
TIMI flows across IRA lesion tell more about epicardial patency while the humble ECG reveals the true myocardial reperfusion.
So ,which will you use for assessment for successful reperfusion ? Ideally both , right !
But , as of 2017 ST segment regression is not considered worthy to define success of pPCI by the all powerful world scientific cardiology community .This is unfortunate (Or Intentional ?) we have ignored this Inspite periodic research papers showing the importance of the same. (Link to this land mark Brodie BR AJC 2005)
Do you know , none of the trials that celebrated the superiority of primary PCI in the last two decades used ST segment criteria. But then ,we realised much later even TIMI 3 flow can have near zero myocardial perfusion. So ,can we now say all these trials are invalid ?
We also never bothered to include no reflow as a liability during pPCI. We have enough data to say even restored No reflow during pPCI has worrying long-term outcome as reocclusion and tissue level perfusion is dismal .(Can we call it a pPCI failure equivalent ?) This is because the Cocktail of anti no-reflow drug we administer often give us a momentary satisfaction with transient myocardial blushes ! (Only to occlude minutes later as the patient is wheeled out of cath lab .We will never ever know how often this happens !) This is because , microvascular bed integrity is notoriously unpredictable and defies the conventional salvage time window . We have seen patients with ultrafast pPCI ending up with severe LV dysfunction.
Final message
If you apply the ST regression criteria by 90* minutes after pPCI (as we do for lysis ) the true success rate of pPCI will emerge .My prediction would be , if you do that routinely the hype of perceived superiority of pPCI might go down the drain (At Least in all low risk STEMI ! ) Let us do a large-scale trial comparing ST regression with TIMI flows, blushes ,frame counts etc and rediscover the true face of our beleaguered coronary microcirculatory sense !
*In fact ST regression should occur much early with pPCI than lysis (May be 10 minutes after restoring IRA patency ! )
Post-ample and a Quiz !
If coronary thrombus laden IRA is the chief culprit in STEMI battle field , Why is that Immediate , routine aspiration of thrombus in the ground zero is counter productive ?
That’s what the sophisticated mega trials of coronary thrombus TASTE, TOTAL revealed. I’m looking for an answer !
Reference
Counter point (and adding more confusion !)
Surprisingly , a Danish(DANAMI) study showed ST regression may not be Important in pPCI .This appears curious , especially when it suggests , ST segment regression didn’t occur because of more complete revascularisation by PCI !
Dr.S.Venkatesan MD 