Spring at the Novosibirsk National Medical Research Center. It turned out that Academician N.Mchlekina was the fruit of unique operations. For the first time in domestic medical practice, surgeons performed a technically difficult operation on a 21-year-old patient to replace the aortic valve with an autograft – its own pulmonary artery valve, and through a small opening – an opening 6 cm in size. At the moment, only two cases of this complex surgical intervention are known in the world.
The fact is that Ross’ procedure – replacing the diseased aortic valve with a valve of the patient’s pulmonary artery identical in structure and physiology – has not been popularized in heart surgery due to the complexity of the operation itself and the narrow range of indications for it. But in the case in question, the patient had a rare congenital heart anomaly – the unicuspid aortic valve. Moreover, in childhood and early adolescence, the symptoms of the defect did not appear. However, over time, the increasing stenosis of the aortic valve (partial stenosis of the lumen) made it difficult for blood to flow into the aorta, which supplies the entire body. With this narrowing of the valve opening, patients experience shortness of breath, dizziness, fainting, swelling of the lower extremities, they can not bear the load, suffer from asthma attacks.
Commented the Director of the Institute of Circulatory Diseases of NN Michalkina Alexander Pugachev Prokofiev. – However, current mechanical and biological prosthetics, unfortunately, still do not meet the functional and physiological parameters necessary for a normal life. Implanting a prosthesis would have affected the girl’s quality of life, limiting her physical activity and forcing her to take anticoagulants for life. Given the young age of the patient and the possibility of pregnancy in the future, we decided to perform the Ross operation. Autograft has good hemodynamic properties, long-term action, resistance to infection. In addition, there is no risk of thromboembolic complications after the operation, and therefore the patient does not need anticoagulant treatment and can return to his normal life. During the intervention, we took the patient’s pulmonary valve, immersed it in an artificial vascular prosthesis to prevent dilatation of the aortic root, and implanted it in place of the affected aortic heart valve. In place of the pulmonary valve, a replica graft (a specially treated implant taken from a donor) was implanted. The entire intervention was performed through a 6 cm small inlet, which became an insignificant alternative to the standard medium approach, which involves 18 to 20 cm sternum dissection. “
The above-mentioned shortcomings of domestic and foreign prosthetics stimulated scientific research by NMIC employees who received grants from the Russian Science Foundation. In particular, the group project under the leadership of the Director General of the National Center for Medical Research was named after F. Academician EN Michalkin Corresponding Member of the Russian Academy of Sciences Alexander Chernyavsky on the creation of a new original hybrid prosthesis for the thoracic aorta. The project of pediatric heart surgeon Ilya Soinov and colleagues should solve the import substitution problem.
According to NMIC statistics, most pediatric cardiac surgeons have complex heart defects that require artificial limbs for blood flow from the right ventricle to the pulmonary artery. To date, such operations have been performed on the open heart under cardiopulmonary bypass, which is associated with the risk of complications. Vascular methods of pulmonary valve replacement have become an alternative. The prosthesis is connected to the affected area of the artery through a blood vessel using a catheter. In this way, complications associated with open surgery can be avoided, and the patient’s stay in the hospital can be reduced to 2-3 days. However, despite the high demand for pulmonary valve prostheses for catheter implantation, there are no domestic analogues of these products, and the use of foreign products is limited to a number of design flaws. With the support of the Russian Science Foundation, scientists from the Melchlin Center are creating an artificial heart valve that has no analogues in the world for pediatric heart surgery. The surgeons and research team of the NN Bioprosthetics Laboratory Dr. EN Meshalkina have already begun developing a self-expanding pulmonary valve prosthesis for transcatheter implantation. Structurally, it is very complex: it is a self-expanding frame made of nitinol with a fixed fold device made of xenopericardium biomaterial that has undergone anti-calcium treatment. It is worth emphasizing that the system for connecting the first home heart valve is several times smaller than foreign analogues, which makes it possible to implant a prosthesis in children weighing less than 30 kg.
Another unique operation, also the first in home practice, was associated with the elimination of arrhythmias in a patient with a defect in the development of the cardiovascular system. A 58-year-old man with atrial fibrillation. In the case of such a disease, the irregular atrial contractions go randomly to the ventricles of the heart and cause shortness of breath, a feeling of rapid heartbeat, general weakness and increased fatigue, and chest discomfort.
In the standard case, arrhythmia is treated by radiofrequency ablation: special catheters are inserted into the heart cavity through the femoral vein, and the left atrium, where radiofrequency exposure is performed, is accessed through the atrial septal puncture. But in this case, it was not possible to carry out a conventional intervention: the patient had a congenital anomaly of the cardiovascular system – the atrial septum consists of two parts. The only way to enter the left side of the heart was through the main arterial vessel – the aorta. Through the femoral artery, surgeons inserted the catheter into the aorta, and then through the aortic valve of the heart into the left atrium, where they stopped the foci of pathological electrical activity. The intervention was performed using an automated navigation system.
And in this field, scientific research contributes to the development of high-tech medicine. As part of another Russian Science Foundation project, a team led by Alexander Romanov, Deputy Director of the National Research Center for Research, is studying the mechanisms of autonomic nervous system dysfunction in arrhythmias. Scientists have developed an effective method for visualizing the autonomic nervous system using gamma scintigraphy and computed tomography, along with 3D reconstruction of the inner surface of the left atrium. This technology allows you to plan the tactics of surgical intervention individually for each patient. Thanks to this technique, the surgeon can precisely influence the areas of pathological activity of the autonomic nervous system using radio frequencies. The intermediate results of the study show that with the standard method, the effectiveness of paroxysmal atrial fibrillation treatment reaches 70%, with the use of a new technique – 87%. This allows us to talk about the first global trial of personalized treatment for atrial fibrillation.
Olga Kolisova
Photo provided by the press service of the NMITs. Academic