Welcome everyone, Jonathan Leipzig here from Vancouver, British Columbia. It's really an honor and a privilege to be helping moderate this discussion with some dear friends and collaborators on a very important and I think innovative roundtable discussion that we had back at Minneapolis Heart on planning PCI with CT. This is an exciting opportunity, I believe, to understand and learn new opportunities for penetration of CT into the cath lab, to help inform more complete and more strategic, hopefully, revascularization. Without further ado, let me welcome and introduce my colleagues, Dr. Jadar Sandoval, who's from the Minneapolis Heart Institute. He co-directed or co-led this discussion and this position paper. He comes to us from the Northwestern Hospital, Abbott Northwestern Hospital, and the Center for Coronary Artery Disease at the Minneapolis Heart Institute. Professor Niemann, who's a professor of medicine and cardiovascular medicine and radiology and cardiovascular imaging at Stanford University Medical Center. Professor Garcia, Hector Garcia, who's MD-PhD section of interventional cardiology for MedStar, and a dear friend, fellow Canadian professor and Dr. Natalia Pena, coming to us from McMaster University. I think this should be a great conversation, a nice balance of two imagers, myself and Dr. Niemann, and, of course, imagers, but also interventionalists with my other colleagues. So, without further ado, let me hand it over to you, Jadar, and you can share some of the initial thoughts and really look forward to this discussion. Thank you, Jonathan, for introducing us. I mean, I'll introduce, taking the pleasure of introducing Dr. Jonathan Leipsick. He's the co-chair for this, and again, and all of us here participate in this initiative. As mentioned, for those of you listening, there's been a lot of interest in the past recent years about using CT beyond its traditional purpose for just diagnosis of coronary artery disease, but can we use these images that are already being routinely acquired in patients that are being referred to the cath lab now for pre-procedural planning? There's been a lot of interest in this. There are some pivotal trials going on. There's been a number of studies looking at different features, whether that's physiology or plaque composition, et cetera, and pretty much recognizing the opportunity, you know, both Sky and SCT came together, a partner, and said, let's identify a number of key stakeholders in this area to pretty much identify and discuss what are the opportunities. So, again, the pleasure here to have Hector and Kuhn, Dr. Pinilla, everybody here, that came together with a number of others, as highlighted in this slide, to discuss pretty much for over half a day what those areas are. This is pretty much the whole group that participated in this roundtable on behalf of both Sky and SCCT on the theme of the use of CT to guide PCI. And, again, this is supposed to be an interview, interactive, so I don't want to take much time, but this is pretty much what we're here to discuss for those of you that may not be familiar with some of those concepts or are trying to get into understanding what the opportunities are. And, again, if we take a step back, all these patients that have suspected engine, you know, suspected coronary artery disease, they are undergoing, for clinical purposes, CT to diagnose whether they have a disease or not. And what we're suggesting here is that there's now increased awareness that we can use this information beyond just diagnosis of coronary disease, but for pre-procedural planning, if we use this in a systematic fashion, and we try to understand what are the elements that we're looking for. On the left of this image, which is the central illustration of this expert opinion paper that will be released at Sky coming up, you can see images that can be routinely acquired from any CT software. Those are the MIP, the maximal intensity projection. This is an image that, again, now both Jonathan and Kun can elaborate on this further. This is an image that had usually not been used by imagers in the routine day-to-day practice because it underestimates, you know, the extent of coronary artery disease. But for PCI planning, for PCI planning, as you can see, you do not have to be an expert to see that you can understand the anatomy, that is this complexity, is there calcium, is there no calcium, what are the optimal angles. Same thing, you can get just by scrolling an image, get an understanding of actual images. You can look at multi-planar reformations to understand disease length and the cross-sections to understand the plaque compositions, is the lesion calcified or not. And again, just with this basic systematic assessment of CT, you can see you can get, again, angles, disease length, morphology, plaque composition, very easily in any patient that comes to the cath lab. Now, beyond that, if the patient is eligible, let's say this is a native vessel without previous stenting, that you can then compute physiology, you can do physiology derived from CT, as shown now on the right. And this unlocks now the opportunity to also go beyond from what we call FFRCT 1.0 to FFRCT 2.0, in which now you're using this beyond diagnostic purpose, but you're using this to phenotype coronary artery disease, understand whether the lesion is focal or diffuse, but critically, get the component of virtual PCI in which now you can understand what is the stent length that will provide an ideal improvement in flow in that vessel. Now, last, you can further complement that with other elements. Some of these ones are investigational, are being evaluated in the pivotal pre-flow trial, but those include things like even myocardial mass and even light guidance in the CT, where the CR will be moving around as you do your procedure. So again, this is a conversation, this is a chat, this is just to pretty much, you know, break the ice and start the discussions, but these are many of the elements that are available in any case, particularly the ones on the left. And I'll be very interested in kicking off the discussion here as to what are the opportunities. Thank you, Jota. That was a great overview, and I really look forward to opening it up to my colleagues to really hear their thoughts, although we've had broad conversations about these topics. But I really think you framed it well as it relates to the pragmatic utilization of CT. I think our focus now, just for the listeners, is not that the proceduralists should be going and ordering the CT, but rather they should be participating as we do in structural heart disease, and really the evaluation and the integration of this imaging into the cath lab. So maybe, not that we imagers couldn't should take a back seat, but maybe I'll pivot to Dr. Pena and Garcia first, and ask you both, maybe Hector for you first, given your decades of exploration of intravascular imaging. Obviously, there's limitations with CT as it relates to the spatial resolution, temporal resolution, but yet how do you then overcome those or accept those and accept those limitations and find value in plaque imaging as a proceduralist or as an interventionalist? No, thanks, John and Yadir for putting this group together and this very important paper. I would say it's visionary, because in a few years we might be saying, you remember when we started talking about this in the United States, using CTA for planning, guiding PCI. Let me frame this conversation or my response to your question by alluding to the current standards, to the recommended class 1a indications for PCI. And when you think about that, of course, the best roadmap we have is invasive angiography. I cannot think of a better angiography imaging than CTA. Let's talk about the next one. So, class 1a is physiology, invasive FFR. We have multiple meta-analyses showing that CT FFR has really the potential to get to the level where invasive FFR is. Let's go on with your specific question on intravascular imaging. So, I would always think that CTA has the best opportunity to give me the plaque geometry and composition, not only of the lesion that I'm going to be treating, but from the full coronary tree. And that's an advantage over intravascular imaging. So, again, when I put together the current standards and the class 1a recommendations, I cannot think of a better diagnostic tool than CTA. That's helpful. And maybe, Natalia, it seems relatively obvious. And obviously, I know you read coronary CT and you've been very engaged in the space for quite some time. What barriers do you see? I mean, we're fellow Canadians, but I'm sure this would apply, obviously, in the United States and broadly. What are the main challenges you find as a busy interventionalist as far as integrating CT and perhaps people that are less facile with CT themselves to actually start to begin this journey? Yeah, thank you so much for that question, because the more we get involved in the CT, the more we realize what the challenges are. And I think cardiac CT was seen in the past just as an imaging technique. And now we are saying this is not just an imaging. Actually, you can use this image and integrate this in the decision making, even before you go to the cath lab to an invasive procedure. So, the challenges I see right now is that the interventional cardiology field hasn't really taken the time to train on cardiac CT itself and maybe taking advantage that if this imaging modality was done in the patient, then you should have a basic knowledge of the cardiac CT to review those images and really use that information in the procedure itself. But if the interventional cardiologists don't take that step and say, okay, this imaging is actually quite important for my procedure, let me understand even the basics and decide guiding catheters, understanding the patient will require PCI that will help you with antiplatelet therapy before deciding your access for the procedure, all of those details that are very helpful. So, I think that's the main barrier I see now, because cardiac CTs get done massively right now, but I don't think we are really using that information before going to the cath lab. I think that's such an important point. And I would just even add to that, that I think the demand or the interest from interventionalists will be important to drive software development that can provide formats that are perhaps more easily integrated into the cath lab. I think that our vendor partners will develop visualization tools, as we saw in TAVR. In the very early days, TAVR was analyzed on traditional workstations that Dr. Nieman and I would use, but now they've created, of course, workflows that are really focused on answering very specific questions. And I think that continued interest will drive that development. And maybe to that end, Kun, I could ask you, you and Hector led a very important SCCT document as well around quantitative imaging. And just for those who don't know, I've collaborated with Dr. Nieman for many, many years, and he always brings such a thoughtful and also critical lens to a lot of what we do, right? With an important reflection, so that we shouldn't be too overly optimistic or excited without the evidence. And I do think it's important as an imager that we highlight some of the outstanding challenges. And Kun, maybe you could highlight some of them as it relates to the, you know, the really routine integration of CT and maybe what we need to continue to do to drive the imaging forward to support this demand. Yeah, no, I think, very fair points, Jonathan. I think we've come a long way over the past 25 years with starting with four-slice CT technology, and now we're entering photon counting technology. And so technologically, we've come a long way, and I always get a little bit embarrassed when interventional cardiologists like Hector compliment us on our image quality, and I sometimes wonder whether that's really true. We do have limitations in terms of spatial resolution. We are not as accurate as invasive angiography or IVAS. Our resolution is lower. When we want to look at plaques, we are challenged by blooming artifacts from calcifications that make it difficult to estimate the stenosis very severely, which may be better with photon counting CT, but it's a known limitation. And then with plaque characterization, we don't have the resolution to see, you know, the necrotic core or the thickness of the cap over the core. But within those limitations, I do agree that CT can be helpful for a lot of anticipation and preparation. I was surprised to hear that in the cath lab, rarely the normal vessel diameter was measured, which is very low-hanging fruit for CT to do. And so in that sense, I think it can be helpful. Another important thing to realize is that, you know, at institutions where we work, we often have access to state-of-the-art technology with technologies that are really, you know, have been trained over many, many years, and this is not available everywhere. And so for this to really grow, we need to increase access to state-of-the-art technology and training. And then finally, I think we need to start talking the same language. You know, when we, Jonathan, when CT actually started, it was from the cath lab, but, you know, gradually it became a first-line technology that we use for risk assessment and decision-making. And we never report, you know, with the interventional cardiologist in mind, and that is something that needs to change from our side. And then I think, of course, and maybe the others can comment on that, what needs to be changing from the interventional cardiologist side to better understand CT. Yeah, that's, I think those are all fundamental points. I see Natalia, I want to get you to jump back in, but I would share one other comment that I think is important, is in addition, is that I think for the imagers to be aware that this is happening, that the test, exactly to your point, is no longer just a rule-out test. So, you know, we really need to prescribe the CT protocols in accordance with the intended use, especially in patients with calcium and known disease, and, you know, obviously focus on radiation dose protection, but also on ensuring that we can use the technology to really answer the clinical questions. Yeah, Natalia, did you have something you wanted to share? Yeah, that's a great point, because when I was hitting that, I worked with radiologists to review the cardiac CTs, and we have learned from each other so much, coming to a common language, and I think that's important, because only until we got to work together, they understood what we need as interventional cardiologists, and we understand how systematic you guys are with the review and the reporting of the cardiac CTs. So, only until that conversation happens, we can really understand each other, and maybe say, oh, actually, understanding if the take-off is anterior, posterior, actually that's very important for us, or relating the plaque location to the main bifurcation that's important to us, or understanding how heavy is the quantification, how extensive is important, only until those concepts come to a common language, then it can really reflect on the procedure itself. So, I really agree with that comment. Well, let me close out this session by asking Dr. Sandoval one last question, if I could. You know, you've brought together a number of people, not just for this think tank, but also wonderful courses with yourself, and Dr. Berlakis, and Kabal Kante, and Cheng, and the team at MHI, modeled after the partnership, and in partnership with the leadership courses that were initially started in OLV in Aalst, Belgium, led by Dr. Collette, and others. Maybe you could share just a couple of thoughts with the sky hat on as well, and SCCT lens. What are the educational needs? How are we going to help support the field to really grow with this space and continue to learn? Thank you, Jonathan. I mean, I think it's clear at this point, we're still early in the process, but I think the data is quite promising, as Hector was alluding to, that the value of this is that before we enter the CAD lab, we can really plan what we need from a number of elements, right? And I think at this point, where we are, is I would say there are two huge unmet needs. One is, we at this point, and again, we will see through many of these educational opportunities, you know, these great slides and plans of how to, you know, look at the MIP, or how to look at the cross-section, or calcium, etc. But now, you know, you have to drive and do this, right? So, there are huge educational opportunities for people to know exactly the buttonology and where to click this. Yes, we want to partner with the chronic imagers, with people like yourself and learn from our imagers. We've done this at our group. But inevitably, you want to have the ability in the CAD lab to open a CT scan and say, this is the guy that I need, or look, this looks specific. So, there needs to be, I think, there are opportunities to introduce some of this education in the curriculum of our fellows, our workshops, and on that note, you know, kudos to Sky. There will be actually a number of workshops at the upcoming Sky Scientific Sessions providing this learning to interventional cardiologists, because we need to know what those opportunities are. You guys see this every day when you're reading CTs. We have historically not as an interventional community, and now we're opening our eyes to, like, maybe we should go beyond just a written paper report, and now we should click and see, all right, perfect. I understand now what Dr. Nieman is saying, that there's severe classification, because we can use those elements to plan our procedures. Now, the other opportunity is this issue about data, of course. I like what you said, where there's some degree of enthusiasm and, you know, coronary field, you know, as compared to structural, there have been not many opportunities in something that would change, you know, can we do better, and CT appears to be that, you know, new thing that appears to promise a better way to deliver better outcomes for our patients and better procedural success. But this needs to be validated, and this is, of course, we're arguing people like Dr. Collette in Belgium is leading right now the P4 trial, randomizing patients in non-inferiority trial versus HDI, but there is a need, I would say, for many such studies to validate in so many lesions. There is data for CTO, as you know, there's data for in the bypass setting, but we need a lot more data to continue to understand what are the opportunities there. So, I will add that it's a very exciting moment in coronary interventions that we have a tool that it's actually an interesting thing. It's a tool that it's an existing tool that has been available for decades, but now we are trying to understand that there are opportunities to better integrate this to the practice and better take care of our patients. Yeah, thank you for that. I think that's so important. You know, as we bring this session to a close, I really look forward to working with all of you and then collectively through Sky and SCCT, there are many outstanding questions, but there are a lot of opportunities to learn and do better for our patients. And I think, as you pointed out, this is, you know, we have a roadmap. This is what we do in structural heart disease. This is what all proceduralists do in imaging, in medicine, they integrate imaging and they go to the cath lab or they go to the procedure room with a plan. And so, I think, collectively, we can better understand how to use these tools to inform decision-making in a fashion that I hope will be more efficient and lead to even potentially a better procedural outcome. So, thank you all for the time. I'd like to thank the team from Sky for bringing us together and look forward to seeing you all soon.

CT scans

PCI procedures

cath labs

revascularization strategies

interventional cardiologists

coronary artery disease