Skye, it's a pleasure to be here and for this kind of invitation. I'm just going to follow on the heels of what Dr. Rab and Dr. Todd had gone over about coulotte technique. We wanted to talk about a single-cell double kissing coulotte technique, which is a slight modification of the original technique. I'll start off with this case of an 83-year-old male who presented with a non-ST segment elevation myocardial infarction. Here's his angiogram here on the left. You can see a caudal view showing severe distal left main as well as osteo-LAD and osteo circumflex disease. You can see a cranial view on the right-hand side. You can see the disease extends into the proximate LAD. Conventional contemporary interventional techniques for bifurcation lesions have really evolved to try and minimize the stent layers at the side branch osteum and avoid the amount of metal to reduce the rate of stenosis rates, which occur predominantly or more commonly at the osteum or side branch, such as a circumflex. As we all witness here, double kiss coulotte techniques emerge as a great alternative to DK Crush for appropriate lesion anatomy. As we talked about, one of the issues is the amount of stent metal in the left main. Our group here at Emory tried to innovate in terms of the technique by coming up with a way where we can have maybe one or two stent struts in the side branch osteum as part of the DK coulotte technique. I'm going to go through the steps here. If you're interested, we've published this paper. It's in Jack Intervention. If you're interested, you can go check it out. I want to thank my co-authors as well for the innovation. Just going back to the case here, we did IVAS of the LED as well as the circumflex. We did a pullback from the osteum from the circumflex. You can see there's severe calcified disease both in the distal left main as well as the osteum as well as proximal circumflex. There's a calcified nodule there in the circumflex. Similarly, in the LED, you can see the severe distal left main disease as well as almost concentric calcification in the osteum of the LED. We decided to start with adequate vessel performed shockwave lithotripsy both in the circumflex and the LED osteum and distal left main here, as you can see. We used impella support mostly because the patient's ejection fraction was 25-30%. Actually, after the first balloon inflation, he had some hypotension. This was inserted after we predilated the distal left main with a semi-compliant balloon. Once the vessel is adequately prepped, we went ahead with our stenting technique. The first step for the single cell culotte technique is to prepare the stents outside the guide catheter, the side branch stents. We uncovered the stent cover a few millimeters here. You can see the stents inflated to 2-3 atmospheres. The proximal struts are opened. We then inserted the main branch guide wire through a single cell strut crossing from one side to another. You can see here in this picture of the side branch stent. After this, we used a one-to-one size non-compliant balloon for the main branch, which was mounted on a main branch guide wire and advanced through the stent struts. Finally, the stent was loaded, as you can see here, on the side branch guide wire. And then, as a unit together, the balloon and the stent were crimped back, as you can see on the right-hand panel. Finally, the entire unit, you can see here, were advancing into our copilot. On the right-hand side, this still image is what you'll see when both the balloon and the stent are advanced into the coronary artery. And so, this is a quick video here, kind of explaining what we just went through in preparing outside of the guide catheter. So, you have your side branch stent here that's inflated to 2-3 atmospheres. We'll then take our main branch guide wire and advance it through a single strut. Or, if you want two struts to cover the ostium of the side branch, you can do two stent struts. We'll then mount the main branch one-to-one sized NC balloon onto this main branch guide wire. You can just see how the wire is crossing through the stent struts there. We can speed it up a little bit here. So, we then take the main branch NC balloon, sized one-to-one, that's advanced through this one cell strut, and then the stent is crimped back onto the balloon, and then we load the stent on the side branch guide wire, as you can see here. And then, the entire unit is advanced, so we're crimping the stent back, and the entire unit is advanced into the co-pilot. So, now we're ready to advance this into the coronary. And so, you can see, going back to our case here, on the left-hand side, the balloon and stent as a unit into the guide, which are then advanced into the coronary. And, obligatorily, once it's advanced, you have coverage of the ostium, side branch ostium, with one or two stent struts, and then the main branch balloon is in place already, as you can see there. We then deployed the side branch stent, 3-5 by 22 millimeter stent, and then pulled the stent balloon back and performed the first kissing balloon inflation, as we described earlier. So, usually, we'll go high pressure, sequentially, and then simultaneous. I usually prefer 6-8 atmospheres. So, what you've done here, essentially, is done the first kiss and re-crossing, which is all prepped outside of the body and then just advanced into the coronary. At this point, we perform an angiogram to evaluate the side branch vessel, make sure there's no distal edge dissection. You can see here, on the left, we then remove the side branch guide wire. The LED stent was then delivered and deployed from the left main into the prox LED, as you can see on the right-hand side. Finally, we performed a proximal optimization technique, and then we rewired the side branch and performed our second kissing balloon inflation, and then performed a final proximal optimization technique. This is our final result here, on the left, the caudal view and cranial view of the LED on the right. As you can see, we achieved really, really excellent minimum stent areas by IVUS of 14 millimeters in the left main, 8.6 at the ostium of the circumflex, and 11 at the ostium of the LED. Some of the advantages of this modified technique are, one, you maintain wire access in the main branch throughout the procedure, and the side branch wire is only removed once after the stent is deployed. One of the most challenging steps, as we've talked about for bifurcation stenting, is rewiring. If you prepare the stent outside the body, the first rewiring is essentially done, and you already have the balloon across the stent to perform the first kissing inflation. This really improves your efficiency, as well as it makes it easier for the guide wire crossing and the kissing balloon delivery. Also, you're guaranteed accurate carinal positioning based on the preparation of the pre-mounting outside of the body. Also, it minimizes the amount of contrast that's used when the first half of the decay coulottes are already completed prior to the stent and the stent balloon being advanced into the coronaries. I think this really minimizes the amount of steps that are actually performed within the coronary arteries and simplifies the decay coulotte technique for left main bifurcation. I would have some cautions and highlight some of the limitations of the technique. One of them is the combination of stent and balloon are pretty bulky. We've done about five cases so far, and we've used a 7-inch guide catheter just to allow for more easier delivery of the combination. Also, we are partially deploying the stent or inflating it outside the body. It is possible, if it's not properly curved back, that proximal stent struts can theoretically get stuck. You may lose the stent in the guiding catheter, so it's absolutely important to keep that in mind. I think this technique is best suited for well-prepared left main bifurcation. It may be very challenging to deliver both the stent as well as the balloon distally, whether through calcified areas or tortuosity. We have not tried this in distal coronary bifurcation lesions. Finally, the technique may not work with ultra-thin stent struts, which can be easily deformed while trying to pre-mount outside of the guiding catheter. That's all I had. Thank you very much. My other question, you kind of told us all the limitations of the technique, but the one thing is most stents right now have abluminal DES coating, right? The drug is coated in the outside. They specifically tell you, don't touch the stent. Now you are doing a lot of manipulation and crimping it back. Do you think that's going to affect? Oh, sorry. I don't think so. I think you also have, if you remember the parts of the stent that you're exposing and you're toying, you're going to have that covered with the other stent, the main brand stent. I'm not as concerned about that, but obviously we don't have micro-CT or we don't have more detailed analysis of the technique to really definitively say that that's not an issue. I may add one thing is that again, everyone should know the devices, what you have in the cat lab. Some of the stents have different size cells in the proximal part of the stent to strengthen the stent configuration. Some of the stents have much smaller cells in the proximal few millimeters. So you have to know which stent you have and you have to be sure that you have large enough cells in the proximal part where you just pick it up. We did, this sounds like a bit the combination of the, it was described the sub-technique. I think it was described 20 years ago to osteostenting and we described in 2014 the single stent string culotte. We didn't prepare it outside the body, but we positioned the stent with TN protrusion, with minimal protrusion and with image guidance, we managed to pick this one protruding cell towards the main branch. But as you say, it was still a tricky thing to get it and kind of unpredictable whether you succeed or not. Indeed, in this case, when you prepare it outside, it's quite a nice idea. Yeah, I think it really, especially if you have patients that are unstable, I think it makes it very efficient and quick to, you've already done the recross and the balloons already in place to do the first case. And you don't lose wire access to your main branch. Just several advantages here to preparing or pre-mounting outside of the guide capacitor. I'm sorry, you can't see Gaber in person, he's having connection issues and video, but go ahead Arasi, do you have something to say? I was just asking John, if you have any questions from the chat we should discuss. We do, and it kind of hits on the point that we saw three very interesting case presentations of the Kulak technique today, and there's obviously a multitude of other bifurcation strategies. One of the participants was wondering, just for the panel in general, and it might be a good final statement, does the location of the bifurcation affect your choice of strategy? Are you basing it solely on anatomy? So the example is, is it just the left main? Are you thinking about that differently than an LED diagonal bifurcation based off your strategy up front? Dr. Raab, why don't you take this question? I think if you're proficient in any of the Kulak techniques, you should be able to do both Kulak in the left main and not in the left main situation. Lately, I've become a little more professional digging Kulak, so I can offer the technique to any location with left main, LED diagonal, and distant right. Of course, Pratik's technique is really most suitable for the distant left main. Many years ago, I actually did try the disabled technique, but the devices are bulky, the stems are bulky, and actually when you sort of open up the cells, you can actually dissect the vessel and the stems and struts are pulled back in one way or the other, so you've got to be very, very careful that you crimp it down properly, and you should actually feel it with your fingers to make sure there are no sharp edges at the back as you do that. And, you know, I think that we should move away from classic Kulak unless it's very difficult to do a first kiss in balloon, but you should always be able to do a final kissing balloon in any circumstance of two-stem technique, that's a must, otherwise you'll have a very high stem thrombosis rate and fatality, particularly if you have a left main situation. My preference, you know, I'm still using a lot of DK Krush for my bifurcation strategies, but it's a good technique to know about, and I think DK Kulak really puts a finishing touch in a classic Kulak. So, do you want to take on this chat question? The Chinese operatives were suggesting that there was high risk of mace with the Kulak techniques. I don't think there's been a study comparing DK Kulak to DK Krush, but what's your take on it? Yeah, so, of course, data are data, and without having the data, we cannot really argue with this statement. I can just think of some important aspects from the trials where DK Krush was compared with other techniques, or DK Krush was compared with traditional Kulak. In the traditional Kulak arm, I cannot tell you the exact figures, but in the traditional Kulak arm, there was a relatively high rate of cases where the final kissing was not performed, they were not able to perform the final kissing. If you think on the bench cases what I am showing, and with this massive deformation in the first hand when placing the second one, it already gives you a hint for potential reasons why you cannot perform final kissing, because, of course, it's such deformation you will never, you really need to be lucky to enter that side branch afterwards with the balloon, or even if you enter the side branch with the balloon, it won't look like a brilliant result at the end in terms of structure. So, for me, the number of cases where you are not able to perform final kissing, the number of cases where you might falsely rewire the side branch because of this deformation which was left there, and considering that this can be corrected by the first kissing and the double kissing approach, I think we can avoid many of these potential late mace risk causing situations by performing DK approach for Kulak. This is, of course, speculation, we have not, we don't have the data, we don't have a clear comparison, but we understood a lot of pitfalls from bench, pitfalls of traditional Kulak which are corrected by the DK approach. Okay, well, thank you very much. We're coming to the end of time. Thank you, Ross, for your moderating session. Thank you, Gabor, for being up in Austria, giving us a brilliant talk, and thank you, Pratik, for sharing your technique, and John for being the chat moderator.

single-cell double kissing coulotte technique

bifurcation lesions

coronary arteries

angiogram images

stents

left main bifurcation lesions