Does Cardiac Catheterization Help After OHCA?

Yes!

Probably.

It sure seems like it.

But, we still don’t really know for whom.

We’ve reviewed several of the prospective and retrospective studies regarding post-arrest cardiac catheterization on this blog over the years.  The general conclusion – the authors are very enthusiastic about their outcomes, but their comparison groups are invalidated by selection bias.  So, unsurprisingly, when a systematic review and meta-analysis of these studies is performed – the same critiques hold.

This review identifies 50 studies with sufficient reporting and design for analysis.  27 of these studies describe use in STEMI complicated by OHCA – and outcomes are largely excellent, compared to typical OHCA survival.  Good neurologic survival, in the 18 studies reporting such, averaged 68.4%.  There’s not much debate regarding STEMI complicated by OHCA – cardiac catheterization, when available.

The problem, however, arises when evaluating patients with OHCA and no clear cause for arrest.  There were 15 studies comparing outcomes with and without cardiac catheterization – and, overall, good neurologic outcome was present in 58% versus 35.8%, with and without cardiac catheterization, respectively.  However, 11 of these 15 studies were retrospective, and patients undergoing conservative management tended to have poorer prognosis at baseline and those who underwent cardiac catheterization tended to have more prominent ischemic changes on post-arrest ECG.

So, it’s another garbage-in, garbage-out sort of meta-analysis and review.  It cannot be used to support universal expansion of the target population for cardiac catheterization after OHCA, and tells us, essentially, what we already knew.  Clearly, some patients – particularly those for whom a culprit lesion is identified – benefit.  For the remainder, the treatment population remains unclear, particularly in the face of the extraordinary resource utilization.

“Cardiac catheterization is associated with superior outcomes for survivors of out of hospital cardiac arrest: Review and meta-analysis”