Paul A. Friedman, M.D., chair, Cardiovascular Medicine, interviews Malakh L. Shrestha, M.B.B.S., Ph.D., director of the Aortic Center and a cardiac surgeon at Mayo Clinic. They talk about aortic regurgitation and how the David procedure has advanced surgical treatment for aortic insufficiency and diseases of the aorta. They discuss key symptoms for aortic disease and diagnostic workup. They discuss the benefits of aortic valve repair using a valve-sparing technique. They also review which patients are likely the best candidates for this procedure. For more information, visit Mayo Clinic Medical Professionals — Cardiovascular Diseases and Cardiac Surgery .
Hi, my name is Paul Friedman. I'm Chair of the Department of Cardiovascular Medicine. And I'm fortunate to have with me today, Doctor Malik Retzer, who uh is the director of the Mayo Clinic Aortic Center of Excellence and he directs our Aortic surgery uh unit for our uh cardiovascular surgical department. Malik, thank you so much for joining me today. Thank you very much for having me today. Um Today, I'd like to discuss aortic regurgitation, maybe a few brief comments about how it's diagnosed, but I'm really interested in the DAVID procedure and how that's advanced the treatment, the surgical treatment for aortic insufficiency and diseases of the AORTA. So just to review for our listeners, maybe make a few words about how patients present with aortic insufficiency and what the key findings and dye plastic tools are. Yeah, in contrast to the aortic stenosis, um unfortunately, with the aortic insufficiency, patient can have a normal life till really cardiac insufficiency symptoms start in. Uh so in most of the patients, they do come with some sort of shortness of breath and then or in some of the patients, they have a routine cardiac checkup and the cardiologist or the physician picks up some murmur. So that's how they get diagnosed with aortic insufficiency. But having said that the third group would be, which is we do talk about Conal heart problem. One of them is a bias feed aortic valve, which is very common because 1 to 2% of the human population has it. So we are talking of millions of people here. So these uh a group of the bicuspid aortic valve, uh patients develop aortic valve agitation. So they are two separate groups. C right? And of course, there's a huge long list of physical exam findings from Corrigan's pulse to quins pulse that Bobby uvula and the pounding pulses because of the big pulse pressure and the low diastolic pressure. But what's really intriguing is some of the new surgical treatments. So, tell me about the David procedure. So classically, actually, if the valve had a problem, it would be replaced. So over the last 50 years, since the first averting valve replacement was done, there are basically two types of valves, one with a mechanical valve and a tissue valve. Both have, you know, advantages and disadvantages with a tissue valve. It lasts maybe 1015 years with a mechanical valve. The patient would be kept on a lifelong Coumadin, which is a big drawback, especially for younger patients. But, you know, in aortic insufficiency, the third choice could be the aortic valve repair. So in 1992 it's quite an old technique now. So Tyrone David in Toronto, in fact, came up with this technique called the val sparing re implantation technique where replaced aortic root but preserved the valve. So over the time, this procedure because it was became very famous and we now call the David procedure. So whereby the aortic valve is preserved and the dilated aortic root and the ascending aorta is replaced with a graft. So, are there any patients who you say are particularly good candidates for the David procedure? Yes. Uh Thank you for asking me this question. This is very important because especially in younger patients, let's say Mahan disease patients or any other cognitive tissue pa uh tissue uh disorder patients, they would have dilated aortic roots but a normal aortic valve and they are usually young, you know, 1520 25 for these people putting in a mechanical valve is a tragedy because they would have 5060 years to look ahead with Coumadin. That is horrible. And a tissue valve is not an option because they would need to come every 10 years. So, if you could offer the David procedure for these patients, they could have put in silly 2030 years uh free uh from uh not only valve replacement but also from Coumadin and redo operation. So we've shown that uh also that after 20 years, also that the freedom from valve replacement is more than 85% in this group also. So this is great for our funds, but also for the bikers video valves. Also, a lot of surgeons have been just doing a valve replacement and B was usually present in, you know, between thirties and the forties. So even they have 30 to 40 years to look forward to life expectancy. So they also, this group is the second most important group. So it's really the younger cohort that people, once they're older above 7075 then maybe it's less important. Yeah, exactly. Because this does take uh at least twice as long as to do a wild replacement and technically more difficult. I think after the age of 70 the results have shown that there is no added advantage because even if you put a tissue valve, it gets quicker and the patients of course, because they don't survive 20 more years, then it's enough. Yeah. So when you're talking to a patient and you're reviewing the options, mechanical valve, tissue valve, David procedure, what do you see is the pros and cons of each choice? So with the mechanical valve, of course, the biggest drawback is that the patients need to be kept on lilo coad. So not everyone is. So, you know, uh sure of taking the medicines at a regular interval, getting checked so that the inr level is at the perfect level. So if someone forgets for 23 months or sometimes I had patients who didn't want to take medicines and comes back with clots in the OD valve. So that has always been the biggest problem because when we say the valve lasts forever, it only lasts forever outside the human body inside. Right? And with the tissue valve, although the tissue valves are getting better every year with new valves, prostheses coming to the market. But they still on the general last maybe 15 years and especially in young age group, it doesn't last that much. So, although the patients do not need to take umin, they do not last long. So they may, they will have to come back again, especially younger patients with the David procedure. The first one was done in 92. If the valve leaflets are still normal at the index operation, then Tyrone has shown in his series over the last 30 years with more than 300 patients that freedom from valve replacement after 15 years was more than 95%. Even my own results that we did in Hanover in Germany, which we published over the years where we had about 800 patients. Now, the freedom from valve replacement after 20 years were more than that 85%. So this is a big advantage and because the valve is a living tissue, the rate of endocarditis is extremely low. It is less than 0.5%. So it's less than not even half a 1%. Whereas with the tissue valves or the mechanical valves both because they are foreign materials inside the heart. There is 1 to 2% chances of endocarditis if the patients are not careful every year. So that's a big advantage. If the valve can be repaired, then I think that is should be done, especially in younger patients. Now. Is, is it a technically difficult procedure? How is it done and how widely is it offered? So technically, it's a lot more difficult than replacing the valve. You had to preserve the valve, take out the hole and replace the whole root re implanting the coronary. So it is technically, it does take years to learn this technique. And because at the end of the procedure, the valve has to be perfect without any vegetation. That's why a lot of surgeons are not really keen to do this unless they can do it perfectly. So that's why, although it's done all over the world, not in big numbers, there are only some centers of excellence in every country that do them. No, that, that makes sense. And um I'm interested in terms of follow up for the uh cardiologist or, or general physician looking after the patient. Um maybe a few general comments about following up the patient who's had an aortic valve surgical therapy and anything different about the David procedure than some of the other procedures we should be mindful of. I think with the more or less it is similar, but especially this is a lot more easier than the let's say the mechanical valve patients or the tissue valve patients because patients do not need to take any Coumadin. I put my patients only on aspirin, postoperatively. And before this SARS, because we have to replace the route, we do uh maybe one CT scan depending on whether how much water we have replaced and then follow up is only echocardiography. So this is a lot easier and you know, because the patients do not need to take Coumadin after this procedure unless they have any other con competent uh problems, uh comorbidities. So this is very easy for the follow up. So maybe once every year, it's enough. Clearly a big advance in the surgical therapy for patients with aortic insufficiency. Uh Doctor Fraser. Thank you so much for joining me today. A fascinating topic. Thank you. Thank you very much, Doctor Friedman.