So my name is Thomas Engstrøm, I'm a professor in interventional cardiology at University of Copenhagen in Denmark.

What is the current research landscape for complete revascularisation in STEMI patients, and what did this trial aim to address?

Well, you know, 10 years ago we used to only do the culprit lesion, but then the question emerged, should you do also the bystander lesions, which we call the non-culprit lesions, to complete the revascularisation for the patient? And a number of studies emerged.

So over these 10 years, it's now quite confident that you should aim for complete revascularisation. And one of the studies was the DANAMI-3-PRIMULTI in which we randomised patients to culprit-only PCI versus complete revascularization guided by physiology in terms of FFR below 0.80.

And the present data that we have is that the ten-year follow-up shows that the benefit of complete revascularisation continues over the years up till now. So that's basically the preview of our recent data.

What was the study design and patient population?

So this was STEMI patients, myocardial infarctions with occluded arteries. It was a study that was conducted at all the centres in Denmark and those that had more diseased on the culprit vessel, meaning if you had more than 50% angiographic stenosis, could be randomised in the study.

What were the key findings?

So the original finding after the median of three years of follow-up was a hazard ratio of 0.56 in favour of complete revascularization. And the 10-year follow-up shows also a quite remarkable reduction in events with a hazard ratio of 0.76, which was significant in favour of complete revascularization. So that was the main finding.

On top of this, we could see from the curves and also from LANDMARK analysis after one year and three years that the divergence of the curves continued over time. This means that the events are not only occurring in the first time after your STEMI, they continue to come dripping by along the years.

What are the take-home messages for practice?

After the initial trial we aimed at complete revascularisation afterwards and this was supported by a number of other trials. For instance, the COMPLETE trial with 4,000 patients that showed the same. So I think that's the practise now—it's also in guidelines.

But of course, the interesting thing about the current data is, is this an effect that would level off? Meaning that for instance if you're elderly there's no need to do complete revascularisation because it levels off quickly. We found the opposite. So the practise here now is that we will do complete revascularisation on all STEMI patients.

What further research is needed in this area?

Yeah, there is a really intriguing question and that is FFR is a physiological-based description of the lesion, meaning, does it give ischemia or does it not give ischemia? But you can have non-ischemic lesions, meaning that they are not flow limiting. They can, however, be vulnerable. So even though not giving ischemia, the plaque can rupture and also give rise to a myocardial infarction.

So I think next step will be to investigate whether you should do the ischemic lesion. But on top of this, by means of imaging, should look for non-ischemic lesions that are dangerous and maybe prophylactically stent them as well. So I think that will be the next step.