Aortic valve replacement with a mechanical valve requires anti-coagulation therapy. Use of blood-thinning medications is particularly dangerous in elderly people. Dr. Anton Titov, MD. They have a higher risk of falls. You have studied the risks of using mechanical and tissue aortic valves in aortic valve replacement surgery. What is your method of aortic valve replacement? Dr. Anton Titov, MD. What factors influence your choice of tissue aortic valve or mechanical aortic valve? How to choose the best type of aortic valve for replacement, especially in elderly patients? Dr. Jürgen Ennker, MD. Yes, this is a very important point. 20 years ago we started surgery in our institution. We implanted more than 90% mechanical valves. Now it's just the other way around. Why did this happen? The risk of anti-coagulation is bleeding, cerebral infarction, embolism. If the patient is not taking the medication correctly, he may get a thrombosed heart valve. That is an emergency situation. Because the valve will be obstructed. The patient will have risk of embolism of thrombotic material. So we have patients who are not able to take their medication correctly. This leads to a risk of 0.7% to 1% complications per year. So after 10 years we have 7% to 10% risk of aortic valve thrombosis. This led to us to the current practice that more patients are getting biological aortic valves. Dr. Jürgen Ennker, MD. You don't need oral anti-coagulation with a Medtronic Freestyle valve. This is true with other models of biological heart valves. These patients only get 100 milligrams of aspirin per day. Aspirin is also recommended for patients older than 50 years. It's a relatively low dose of Aspirin. Absolutely, that's a very low dose. Actually I'm taking Aspirin myself because I'm over 50 now. Medical articles in The New England Journal of Medicine say you get less cerebral infarction and less myocardial infarctions if you take Aspirin. Dr. Jürgen Ennker, MD. So we should come back to the aortic heart valves. In previous times, patients received only biological valves when they were older than 70 years of age. Because the idea was that the heart valve would be more durable than the life expectancy. Because the surgeons or the patients were afraid of re-operations. Nowadays re-operation is not such a big risk. For example, we implant biological aortic heart valves also in patients of 50 years of age. If the heart valve fails after 10 or 15 years, the patient enjoyed 10 or 15 years without oral anti-coagulation. He did not have any problems. Then we will see how the medical technology will be developed. If you have a patient 65 years of age, a re-operation is not as big a problem as it used to be. Repeat surgical operation should have the same risk, the same mortality, as the first operation. The risk of death is 1% or 2%. At least it is less than 3%. And patient is saved several percent of complications. Dr. Jürgen Ennker, MD. This would happen if a patient would have used oral anti-coagulation. So we're using biological heart valves in younger patients. We don't wait until the age of 70. Dr. Anton Titov, MD. Because, what happens if a biological heart valve fails? Most of the time a heart valve leaflet will tear. Then patient develops cardiac insufficiency, he gets shortness of breath. But this is not a cardiac emergency. This has to be operated the same day due to the risk of embolism or thrombosis. So basically a patient with a tissue valve has a little bit more of the time to get an appropriate operation as a planned operation. Dr. Jürgen Ennker, MD. Absolutely, that's the point. Patient can make a decision. Dr. Anton Titov, MD. Does he want to have another cardiac operation? If he is 70 or 75 years of age, does he want to have a transcatheter aortic valve implantation? There is more time for reconsideration. So in your hands it looks like the tissue aortic valves are really gaining our confidence. There is a wider use of indications at the younger age for pig or cow aortic heart valves for replacement. Dr. Jürgen Ennker, MD. Yes, but there are other publications who will state that even a younger age, mechanical heart valves are adequate. So we should inform our patients and they should make their own decision. Dr. Anton Titov, MD. Do they want to take oral anti-coagulation every day? Or do they want to wait what happens to their implanted biological heart valve without having oral anti-coagulation?