The inclusion criteria were comatose survivors of out-of-hospital cardiac arrest (OHCA) that had shockable rhythms and return of spontaneous circulation. Patients were excluded if they had STEMI in the ED, shock, or an obvious non-cardiac cause of arrest.
The study was powered to detect a whopping 40% difference between the groups. Of course, it is quite ambitious to think immediate angiography would be so efficacious. Therefore, the study had an “adaptive design” that allowed for an increase in sample size if they detected a trend towards benefit during an interim analysis of the first 400 patients. (Kinda sounds like cheating… but I get it)
Those Dutch know how to conduct a study (must be something in the Heineken).
Adherence to protocol was fantastic. Median time to angiography was about 45 minutes in the immediate group and about 5 days in the delayed.
Acute thrombotic occlusion of a coronary vessel was found in a small minority of patients. Only 3.4% in the immediate and vs. 7.6% in the delayed. As such PCI and CABG was performed less than a third of the time.
I think you know where this is going… this was a negative study.
At 90 days 64% of the immediate group and 67% of the delayed group were alive.
So what should we conclude?
I think it is safe to say that we should not send all patients with OHCA without STEMI to the cath lab.
But one of the major challenges with evidence-based medicine is extrapolating the results of a study to the individual patient in front of us.
What about the patient with some degree of hemodynamic or electrical instability? Or what about lots of dynamic ST and T wave changes on the ECG (of course this could also come from intracranial catastrophe)? What if they just smell like a coronary occlusion?
In summary, don’t send all patients to the cath lab. But I think we should still consider it on an individual basis. Now back to my Grolsch...
Covering: Lemkes JS, Janssens GN, van der Hoeven NW, et al. Coronary Angiography after Cardiac Arrest without ST-Segment Elevation. N Engl J Med 2019;380:1397-1407. [link to article]
Dr Brian Doyle is an emergency physician originally from the United States but now very much calls Tasmania his home. Unfortunately, it will now be a bit more difficult to deport him from the country as he passed his Australian citizenship test a few years ago. (He was able to answer that Phar Lap won the Melbourne rather than the Davis Cup). His main interests are mostly the clinical aspects of emergency medicine but also in education, ultrasound and critical appraisal of the literature. He spends much of his time annoying people to help out with conferences.