- Let's discuss aortic valve replacement in elderly patients. You have very extensive experience, you have published a series of 493 consecutive elderly patients in whom you did an aortic valve replacement. In half of those patients you also did Coronary Artery Bypass Grafting [CABG], either close to the time of aortic valve replacement surgery or together. And these are patients who are over 80 years of age. What have you learned from your very large experience about heart surgery in elderly patients? What is the best way, how do you approach in your practice aortic valve replacement in elderly patients, over 80 years of age? Well, first we have to differentiate between the biological age and the numerical age, because you have patients who are biologically much younger, and they are more fit for a cardiac operation. The second, you always have to listen to the patient. If the patient says, "I'm too old, this is nothing for me," don't force the patient into any operation. The patient has to want this operation, and he has to follow the recommendations, what he has to do after the operation. He has to cough, he has to breathe. He has to mobilize himself. And then we are able to get an adequate result. So listen to the patient. And the other one is we have to consider the risk factors. So if a patient is nearly 90, he has had previous operations, he is in a low cardiac output, he has renal disease, surgery may not be adequate solution for this patient. But we are very fortunate for patients who are unoperable by conventional surgery, we have the so-called TAVI technique, transcatheter aortic valve implantation, where we can place a catheter into the groin and bring the valve into the patient's aortic annulus. And then we can replace the valve and there's no need for regular operation, just the catheter procedure. So this is taking place in Germany right now. About 50% are operated interventionally by such a TAVI procedure and the other half is enjoying a conventional procedure. So patients over 80, they have to make up their mind because, as you know, a man, for example, in Germany if he's 80, he has life expectancy of 6.9 years, women have about 8 years. And if they don't get such an operation, they will lose several years full of quality life.

- So this is very important. It's not just a question of biological age, but it's a question of fit of the patient and psychological desire to do an operation and have a higher quality of life.

- Absolutely!

- We have the so-called frailty index, which measures the ability of the patient to survive such an operation and his level of fitness, and this is very important.