I think, overall, I chose this case not that this scenario comes up every day, but I think one of the concerns we often have is if you have an issue that it's difficult to rewire the side branch and occasionally, you know, patients are pretty unhappy during that period of time. And so one of those cases would be a dissection because of managing sub-intimal issues with that. So this is a case where I think that's employed, but does sort of highlight how doing a mini-crush or DK-crush strategy helps you protect that side branch and makes re-accessing it easier because of some of those escalation strategies. So this is a 60-year-old woman, this was a couple of years ago, that she presented with an NSTEME, difficulty wiring the diagonal, which was the culprit, and she was basically left with medical management, but unfortunately had quite a bit of ongoing angina, normal EF, was, you know, clinically doing well, was an active person. So we, after some discussion in clinic, had brought her in and basically started off with IFR of the LAD just to see how significant that was. I think it's one of those cases where you have a few options, but if we, you know, many times to prioritize the LAD over the diag, maybe you'd miss in just a hair with your stent or try to T that or line that up, but there's enough disease in that area, the bifurcation of the LAD. You're always thinking things can always get worse in these cases, so if I mess up something with the LAD, what options would we have? But that was marginally significant, and also did IVUS there just to kind of understand if we needed to do a lot of vessel preparation for the LAD, I think easier to do that before we get busy wiring the diagonal, so. With that information up front, she does have a little bit of eccentric calcium, but fortunately not too bad here. So after that, we leave basically a safety wire down the LAD, and not too unexpectedly also got sebentamol in the diagonal branch there. So spent a little bit of time trying to rewire that, and I think this is where Ministar can be helpful as a bailout if a patient's really acting up during a case or if this is a large area in particular without a lot of side branches. So basically you see the knuckle on that screen on the left here just starting to fold over. Didn't like that shape as much, but a lot of the wires that will form a smaller knuckle will reenter pretty rapidly in an area of more healthy tissue and especially at an area of side branch. So you are basically just advancing that wire without torque or really any skill involved at all. But what you're looking for is that movement and getting some acceleration as it shrinks as it comes forward, and so that's what we're seeing here. We use that marker from the fluorosave to decide how far we need to balloon so that we can connect the areas of flow to the normal trulumen in the distal vessel. So here, it's common in these cases, is a 2,540 balloon just to basically massage some of that. And you can see here, we not unexpectedly have a large dissection plane here at the ostium, but do have some restored flow there into the diagonal branch. So at this point, I think IVAS for landing zones is quite helpful. It will say in most of these cases, you know, we're doing this as a bailout for CTO-type techniques. In most of these cases, we wouldn't put a stent in at that time unless we're quite sure about landing zones and the flow and let that heal. But because we were going to gel that with the LED stent, we had pretty good outflow. And also, it looks like we have a reasonable spot to land here in the distal vessel of the diagonal. We went ahead and did plan to proceed with that. So we've got reasonable flow here. This is after a little bit more modification of the actual LED. And so, you know, she's doing well, and so decided to go ahead and start with the sidebranch stenting. So here, many times, you're not necessarily going to, you know, stent out to the apex of this vessel. The re-stenosis rates are quite high in those circumstances, but trying to find a good landing zone with our IVAS imaging and knowing about where we re-entered, we put, I think, a 2,538-millimeter stent in there. And I think one of the kind of simple, quick check marks that we're doing here is if I'm really worried about an edge dissection—obviously, in this case, we have diffuse dissection planes and we're checking for flow—but if you're worried about an edge dissection, that's easier to manage now, because otherwise, the stent there really makes that rewiring into the sidebranch quite a bit easier. It can be more aggressive with jacketed wires, and we're not worried about managing that. In this particular case, obviously, we're expecting some dissection planes there, but we do have some good outflow so that we're prepared to pull that wire as well. I think this is where having the main branch IVAS already done is quite helpful so that you can appropriately size that balloon. One of the mistakes I have certainly seen and done myself is being a little wimpy on that balloon in the main branch, and so getting an ineffective crush, it's a lot easier to catch the stent and a lot harder to rewire, and I like that question about which cell that you're going after. So if you don't have an ineffective crush there, that makes that a lot more challenging, and the metal often ends up getting crunched more under the main branch stent, something that we can see on imaging after the fact. So I think in these cases, if I have a patient who's really hemodynamically not tolerating or I'm concerned about tolerating that, so more specifically the left main, I think the priority is just opening the ostium here after the first recross, and really that first recross or first kissing balloon inflation is facilitating the second and final one, so we get final optimization, so really that's the benefit there. I've seen that skipped. It's not that you can't complete the case and get good results, but oftentimes that is when that recross is more difficult or that there's an incomplete stent expansion in the side branch stent and that something there was missed. If there's any concerns about that, this was heavily calcified or we thought we could get away without atherectomy, but we're on the fence, sometimes just IVUSing or making sure that we've got that side branch optimized, I think at this stage before crushing is helpful, but most of the time here we'll just do that and post-dilate at the same time of doing the gel break there. So then, of course, we're bringing the LAD stent. We were a little too proximal here, so we'll advance that based off our IVUS landmarks and then go ahead and do the first pot. The other comments about ways to make sure that you're within that branch, if there's not a lot of seismic match and you've pretty aggressively deployed the stent, sometimes I'll skip that one. Again, if I'm really just trying to be efficient in a case, you just have to be absolutely sure you're not around that. So oftentimes just jam the wire through that segment I think actually can be enough, but certainly any time there's a lot of seismic match, it's just good to make sure that we've got that optimized. So the rewiring for the second time here, we're looking to go more distal to avoid that metal into the carinae, do our second kissing balloon inflation, and then a final pot. So altogether, I think while this is not perhaps a very common scenario, I think there are other cases where once you get into vessel preparation or doing some issue for the main branch, if you have a dissection in the side branch, that's where I think this is a preferred strategy. And it also just helps you to maintain your main branch access throughout the case. So really your risk of losing control of the LAD is effectively zero as well. So I think from a safety standpoint, if you run into dissections in a bifurcation case, that's why I like this strategy. Some of the principles of decay crush were already mentioned. I think just to highlight that, that hadn't made a lot of sense to me of where we're crossing. I will admit sometimes depending on the angles, I don't know for sure which strut we're crossing, but doing that where you advance the wire in a pullback to try to get a distal one so you have a little bit of sense of where you're dropping in I think can be helpful. But really just visualizing that if you rewire from the proximal cell when you're crossing into the crush stent itself, that way you're avoiding pushing that metal into a segment that's going to be pretty tight. And then kind of the parts to slow down are really for the final kissing balloon inflation that's associated with the outcomes there. And then for the repot, just to make sure that there if I need a more prolonged balloon inflation to really optimize the main branch stent and do that. And I think, again, sometimes if you've already done that and your imaging looks perfect, you could probably avoid that. But it just feels more efficient. And usually the bigger thing I'm looking for on my final imaging run is that whether or not that pot was done enough into the carina. So I know for me, if you've got like a 5-0 balloon in the left main and you're worried about putting that too far into the LED, you might err on the side of caution and actually miss the distal left main. And those are the things that we're looking for in our final IBIS. So I think case planning here does help keep the case efficient just so you kind of know what your priorities are, keep going. Really, now that we have both physiology to help guide some of the up-print decisions, but especially with imaging, we're not guessing about sizes. So our crush is more effective and all of the results really do look better because we're not guessing about the sizes. So between that and atherectomy for vessel preparation, I think these cases really have gotten a lot simpler. And again, I think a decay crush just helps if you're worried about something like a dissection where rewiring it and salvaging it for provisional may be difficult. Thank you.

interventional cardiologist

NSTEMI

diagonal artery

mini-crush strategy

DK-crush strategy