Cardiac surgeon Marko T. Boskovski, MD, MHS, MPH, provides compelling data on the ultimate failure of traditional valve replacements to support the lifespan of physically active non-elderly adults and describes the value of the Ross procedure – calling it “the only replacement option that restores long-term survival.” Learn details that illuminate why the Ross autograft holds up over time and how the multifaceted Ross center of excellence at UCSF serves patients referred for aortic stenosis or regurgitation.
Hi, my name is Marco Boskowski. I am a cardiac surgeon at the University of California San Francisco, and I'm also the director of the Ross and theortic Valley Preserving Program. And today I wanna talk to you about this program and specifically about the Ross procedure which we perform at UCSF, um, in particular on both uh the Ross procedure and aortic valve uh preservation or repair is a group of procedures that we tend to do for younger patients with aortic valve disease, uh, and that's what we're gonna talk about today. So as I mentioned, our focus today is to talk about non-elderly adults who have aortic valve disease, and what do I mean by that? Well, these are patients who have high level of physical activity, who have certain quality of life going into surgery and an expectation of a certain quality of life afterwards, as well as most importantly a prolonged life expectancy. And the reason why this matters is because traditionally we perform aortic valve replacement to treat aortic valve disease, and the two types of valves that we normally use, which are tissue valves and mechanical valves, have certain complications that tend to compound over time. So for tissue valves, that's degeneration and potential reoperation and for uh mechanical valves, it's bleeding and thromboembolism. So what are we talking about? Well, certainly we can have a young gentleman such as the gentleman up here who is perhaps in his mid-30s, but we can also talk about a lady such as the one on the picture there that may be in her mid-50s where her expected Life expectancy is close to 30 years, so if we were to treat her aortic valve disease, we have to think of a solution that's going to last almost 3 decades, and this is where the Ross procedure and aortic valve repair tend to shine. So as I mentioned, these tend to be problems that we have to plan for for many years, and oftentimes we talk about different sequence of events in terms of valve replacement, whether that be surgical valve replacement first, followed by trans catheter, aortic valve replacement or caver or vice versa. So it's important to realize that currently there is no robust data for tavern and non-elderly adults. So accordingly, the guidelines do state that if you are non-elderly or under 65 years of age, surgery is the preferred option for the treatment of aortic valve disease. So, this diagram illustrates our approach at UCSF in treatment of adult non-elderly adults with aortic valve disease. As we know, there can be aortic stenosis and aortic regurgitation, and in patients who have aortic regurgitation, if the aortic valve cusps are repairable, then our preferred option is to do aortic valve repair, and this is both in patients who have aortic aneurysms and those that don't have aneurysmal disease. However, if we have aortic regurgitation with disease cusps where we cannot repair the valves, then our preferred option is the Ross procedure. This is also the case for aortic stenosis, where by definition the cusps are very calcified and they obviously cannot be repaired. So why the Ross procedure? And the reason is that traditional aortic valve replacement leads to suboptimal long-term results in young patients. Certainly the short term results are quite excellent, but the long term results can certainly be improved upon. This is a paper that was published in the New England Journal of Medicine where they looked at almost 10,000 patients that underwent isolated aortic valve replacement, and these were young patients under 65 years of age, and this was based on the California registry. So these are our patients that we treat every day. And the main point of the paper was actually to look at outcomes comparing biological versus mechanical prostheses, but you will notice is that regardless of the valve, if you were 45 to 54 years of age, Your mortality at 15 years after isolated AVR was 26 to 32%, and if you were 55 to 64 years of age, your 15 year mortality was 32 to 36%, certainly higher than what we would imagine. So in 15 years, a quarter to a third of patients with AVR are dead in the state of California. So that's pretty impressive numbers. So I will submit to you that conventional aortic valve replacement in the young leads to excess mortality and is a palliative procedure. This is another study from Sweden from the Sweetheart registry where they looked at. How patients did after aortic valve replacement based on how far out they were from surgery. So in the white dots we have the general population, and the black dots are patients who have had aortic valve replacement and you will see that starting at about 6 to 7 years after surgery, there is excess mortality among patients who have had aortic valve replacement compared to the general population. Now you might think that perhaps these are patients who are older who have more comorbidities, who are sicker that are driving the signal. So to address this question, the authors looked at the observed over expected outcomes based on age group, and actually the reverse was true. So if you were older, then your observed over expected mortality was 1.0. In other words, there was no excess mortality. But the younger you are, the more excess mortality there is, and the observed over expected ratio is over 4 if you're under 50 years of age. So most of the signal is actually driven by younger patients and not by older patients. And this is an older study that was published in 2000. There is An updated series that was published in 2019 in the Journal of the American College of Cardiology where the findings were exactly the same. So we have the expected survival of the general population in the red curves and the observed survival in the blue curves, and if you'll see if you're 80 years of age and more, the two curves are superimposed, but if you're younger, there is excess mortality. So, as I mentioned, conventional AVR leads to excess mortality, appears to be a palliative procedure in the young, and the question is why. And the reason is that the aortic root and the aortic valve is a living structure. So, there is a certain durability, excellent hemodynamics, low thermogenicity, resistance to infections that comes from this living structure. And this is translated to better survival, lower valve related complications, better quality of life. So if we can find a living solution to aortic valve disease that can be superior to aortic valve replacement with a man-made prosthesis where this is no longer a living structure. So when we talk about options for aortic valve replacement. Folks tend to focus on the different characteristics of mechanical versus biological valves, but to me they're all one and the same. In other words, they are acellular non-living substitutes with no potential for growth, repair, or adaptation, and this is why it leads to suboptimal results. So what is the Ross procedure? Well, in the Ross procedure. As shown in this video here from a recent surgery that I did, we take the patient's native pulmonary valve, and we use that as the replacement valve for the aortic valve. And when it is implanted in the aortic position, the pulmonary valve continues to live, it continues to have resistance to infection and is able to repair itself to damage. And then to replace the pulmonary valve that was taken out, we use a homograft or cadaveric valve as a replacement. So I will argue, and hope to convince you that the Ross procedure is the only replacement operation that restores long-term survival following aortic valve replacement. This is a study that was done from the same California registry that I showed you in that New England Journal paper, and it was also combined with the New York registry, and they took 1300 patients, young patients, meaning aged 36 years of age, and the propensity matched 1 to 1 to 1. Patients who had the Ross procedure versus those that had tissue AVR versus those that had mechanical AVR and that followed them on average for 12.5 years and what you will notice is that one, the Ross Boort survival was equal to the matched US general population. And two, that those patients that had AVR either with tissue or mechanical valve had a hazard ratio of 2.5 compared to the Ross procedure in terms of long term mortality. This is another paper that was recently published in JAMA Cardiology. This is based on a randomized trial that was done in the 90s by Magdi A Coop, one of the pioneers of the Ross procedure, where they randomized the Ross procedure to homograph the aortic valve replacement, which we do not do anymore, but they took the Ross cohort and they've now followed it for 25 years. So this is the original cohort of 108 patients that were that was randomized in the 90s. Their median age at the time of operation was 38, and the median follow up is 24 years, which is almost unheard of in terms of studies that are done today, and the completeness of follow-up was 98%, so excellent follow up. What you will see on the graph is that the survival of this cohort is indistinguishable from the general population. As you see on this graphic, it's an illustration of what a Ross program should look like. Obviously there has to be a Ross surgeon, an experienced Ross surgeon, but we need much more than that. We need dedicated cardiac anesthesia. We need advanced ISU services, as well as cardiologists with valve expertise, as well as expertise in multi-modality imaging, and the Ross program here in the team. He is certainly expert in all of these aspects of care. So I've presented some data that unfortunately shows that traditional aortic valve replacement can lead to suboptimal long term results in young patients. But I've also presented the data that's hopefully convincing that the Ross procedure is the only replacement operation that restores long term survival following AVR. What does this mean in practice? Certainly both aortic stenosis or regurgitation that warrants intervention can be eligible for the Ross procedure. This is regardless of the valve nephrology. So regardless of whether the aortic valve is tricuspid, bicuspid, or even unic cuspid, which is not uncommon because a lot of the patients are young. Another category are patients who have root aneurysms with significant aortic valve pathologies that we can't repair. And typically this in practice means asymmetric bicuspid valves that are difficult to repair. In terms of the age where these patients benefit from the Ross procedure, certainly if they're under 55 years of age, Ross is the preferred option at UCSF, especially when the patients are healthy. If there's major organ dysfunction in terms of kidney failure, liver failure, or other organs, then perhaps the Ross procedure doesn't make as much sense. But otherwise we prefer the Ross procedure if you're under 55 years of age. For ages 56 to 60, we will consider it, but it has to be a patient who is not only healthy but also very active and stands to benefit from the long term benefits of the Ross procedure. And the point that I'm trying to get across here is that we try to provide individualized care and decision making for each individual patient. So with that, I want to thank you for your attention. This is my email. If you have any further questions or if you have a patient who may benefit or should be considered for the Ross procedure, please do not hesitate to contact us. Thank you.
