Sometimes the aortic valve tightens, the one that opening and closing regularly makes the blood pass from the left ventricle to the aorta artery which must then distribute it throughout the body. In fact, this valve can lose its elasticity and tend to calcify, creating an obstruction to the passage of blood, with a consequent decrease in expectation and quality of life. We talk about stenosis of the aortic valve, a disease whose incidence continues to increase, also due to the aging of the population. This condition represents a challenge for the heart surgery of the future, called to identify targeted therapeutic techniques and strategies.
Heart valve surgery has already reached a very high quality standard and is the scene of significant innovations. There Tavi, an acronym that stands for “transcatheter percutaneous implantation of aortic valve”, allows for example to implant a new valve without the need to open the thorax, using a peripheral artery as an access route (percutaneous route). The method is now more than ten years old and comparative data with the standard surgery are available. The problem is choosing the right solution for each patient. Scientific studies are underway, such as Outstanding Italy of the Cardiology Network, which assess which type of intervention is able to improve not only survival, but also the quality of life, especially in the elderly population in Italy.
How to choose the tailor-made treatment
Age is undoubtedly one of the main factors guiding the choice between the two approaches. As he explains Lorenzo Menicanti, director of the heart-adult surgical area at the IRCCS San Donato Polyclinic in Milan and president of the IRCCS Cardiology Network: “If I have to operate an elderly patient, eighty years old, who is certainly more fragile and with many risk factors, the my first choice will be the minimally invasive approach. If, on the other hand, I have a patient of fifty, with a normal life expectancy, standard surgical therapy is probably the best solution. Not only that, with the Tavi, the valve that is implanted is biological, that is of animal derivation, while with standard surgery I can choose between a biological or mechanical valve, with carbon materials “. The biological valve has a limited duration in time (about 10-15 years) and must therefore be replaced, the mechanical one does not have this problem, but requires the intake of an anticoagulant for life, to avoid a possible risk of ischemic stroke. “The data published by the clinical registers – reports Menicanti – however show that patients around the age of 55 or younger take advantage of the mechanical valve, while above this age the two valves are equivalent. The type of intervention is therefore , chosen on the basis of several factors that also include conditions in general. In very complex patients, with significant atherosclerosis, the femoral route may not be viable; alternative routes may be used (radial of the wrist or brachial of the arm) but may be less effective. Therefore, in both cases, traditional or minimally invasive surgery, the procedure that most increases life expectancy and improves its quality should be considered and recommended to the patient “.
Elderly, a combined no-scalpel technique to treat a diseased heart
by Federico Mereta
What science says
Tailor-made treatment, therefore, is the word that guides the expert. With the Tavi, for example, a new valve is implanted, which “crushes” the native one and takes its place. This is a widely studied technique which has proven effective. “Inside the catheter, which passes through the femoral artery and enters the diseased valve, there is a valve that is extruded – adds Menicanti. – The fact of compressing the native valve can lead to three scenarios: the first is the non perfect adhesion of the new valve against the native valve and therefore the possibility of a certain reflux. The second possibility is that, by compressing the native valve, the conduction tissue, that is the one that conducts the impulse between the atria and ventricles and gives the rhythm the heart itself may be damaged and a pacemaker must then be implanted. In the third case, the compression of the native valve frees the fragments of the valve itself which could create embolisms (stroke in the brain or in other districts). These complications are also present in traditional surgery. For example, according to data published by major international clinical registries, the possibility of suffering a stroke with the surgical approach ico standard is around 0.9%, with the Tavi being around 2.5%, so it’s a minimal difference. The need for a pacemaker is around 3% in the first case, while with the Tavi it is around 7.5%. Both procedures have enormous value beyond the differences; we need to understand what is the best approach for the patient “.
And it should not be forgotten that the clinical and engineering development of extracorporeal circulation, necessary in traditional surgery, has made enormous progress and pursued more and more the miniaturization of the circuits, that is, the reduction of the total length of the artificial path that the blood is obliged to fulfill. It ensures the patient a cardio-respiratory function as close as possible to normal physiology and minimizes the contact of the patient’s blood with external elements such as air, for the benefit of greater safety.
What awaits us tomorrow
“Transcatheter procedures will increase in the future, as we have seen for coronary angioplasty for the treatment of coronary stenosis – concludes Menicanti. – As we continue to acquire data, however, we will always better adjust the shot, improving our experience on the type of patient who can benefit the most from the different methods. Another field where we expect novelties is that of valves, so it should no longer be necessary to take anticoagulants. There are studies in progress, and valves, instead of be made with materials of carbon or metal derivatives, they could have for example plastics. They will therefore be valves that, in theory, do not degenerate like biological ones, but that behave as if they were “.
The wireless pacemaker that “melts” when it is no longer needed is on the way
by Federico Mereta
