Every year, the frequency of use of biological prostheses for treatment of valvular heart disease increases.The implantation of a biological prosthesis allows avoiding lifelong anticoagulant therapy, but at the same time it may require further replacement due to the dysfunction development.Traditional reoperation is associated with a certain risk of trauma to various structures and cardiac chambers during explantation of non-functioning valve.Transcatheter replacement of the prosthesis (“valve-in-valve”) is not always realizable due to lack of routes for the delivery system and small diameter of the initial valve.“Valve-in-valve” is not always demanded because it does not provide an option to choose mechanical or biological prosthesis.Valve-on-valve implantation technique implies that the new prosthesis is implanted in the carcass of the previous valve. It allows avoiding severe intraoperative complications, reducing the duration of the main stage of the surgery and adverse events in the early postoperative period, and provide an option to choose implantable device.In this review, the authors attempted to comprehensively evaluate the world experience in applying the “valve-on-valve” technique.

Aim: to evaluate the manipulative properties of the system being developed for cardiac valve re-operation on an in vitro bovine heart model.Material and methods. The prototype of the prosthesis being developed, mounted on the implant holder, as well as the dilatation balloon of its own design, were used as the objects of the study. The bioprosthesis «UniLine» of 21 mm size for the aortic position was chosen as the target site of implantation, which was established by the «classical» suture method. After that, the implantation of the tested device was carried out as a «valve in valve» and the quality of the installation and the combined operation of all the components of the re-prosthesis system were evaluated.Results. The test implantation demonstrated the consistency of the proposed method on the basis of balloon seamless fi xation, as well as high ergonomic characteristics: the average time of seamless implantation of the developed prototype on an in vitro animal heart model was 3 minutes versus the implantation of the «UniLine» bioprosthesis – 11 min, Implantation provided a reliable prosthesis The breaking force was 12.9 N, which is equivalent to a pressure of 279 mm Hg.

<p>A clinical case of endovascular correction of a biological mitral valve prosthesis dysfunction by implantation of a transcatheter aortic valve into the mitral position is described. Considering the clinical status of the patient, the condition was determined to be inoperable. Subsequently, based on vital fluoroscopy and echocardiography findings, the patient was implanted with a transcatheter aortic valve in the mitral valve bioprosthesis position. The technical and clinical aspects of the intervention and its results were analysed during the hospital period and for 5 months after implantation. The selected method of treatment was found to be appropriate.</p><p>Received 10 January 2020. Revised 18 March 2020. Accepted 19 March 2020.</p><p><strong>Funding</strong>: The study did not have sponsorship.</p><p><strong>Conflict of interest:</strong> Authors declare no conflict of interest.</p><p><strong>Author contributions</strong><br />Drafting the article: N.V. Rogulina, I.V. Ganyukov, A.M. Kochergina, V.I. Ganyukov, R.S. Tarasov, I.K. Khalivopulo, I.N. Sizova <br />Literature review: V.I. Ganyukov, R.S. Tarasov, N.V. Rogulina, I.K. Khalivopulo, I.V. Ganyukov, A.M. Kochergina <br />Illustrations: I.V. Ganyukov, I.N. Sizova, N.V. Rogulina <br />Critical revision of the article: V.I. Ganyukov, R.S. Tarasov, E.A. Shloido, L.S. Barbarash <br />Surgical treatment: E.A. Shloido, V.I. Ganyukov, R.S. Tarasov<br />Final approval of the version to be published: V.I. Ganyukov, E.A. Shloido, R.S. Tarasov, N.V. Rogulina, I.K. Khalivopulo, I.V. Ganyukov, A.M. Kochergina, I.N. Sizova, L.S. Barbarash</p>

Tetralogy of Fallot (ToF) is the most common cyanotic congenital heart defect. Since the first radical correction in 1954, treatment strategy has been constantly improving. Current treatment of ToF ensures the long-term survival (30-year survival ranges from 68.5% to 90.5%), yet it is still challenging in underweight patients. Here we present a clinical case of two-step surgery which included right ventricular outflow tract (RVOT) stenting and further radical correction in an underweight child who was then followed-up for six years. RVOT stenting is an appropriate alternative to the bypass surgery which has higher risk of perioperative complications. RVOT stenting significantly reduces hypoxia, enhances the development of the pulmonary vasculature and increases end-diastolic index ultimately permitting efficient radical correction after 4 months. The described approach resulted in a favorable outcome and quality of life after 6 years of follow-up.

<p>Owing to the development of prenatal diagnosis and interventional cardiology, newborns can survive complex palliative surgical procedures. Modern methods make it possible to change the principles of treatment for children undergoing haemodynamic correction, the last surgery being Fontan operation, and also stimulate the development of hybrid interventions (catheter procedures and surgical operations in the neonatal period). This article presents the dynamic monitoring of a child diagnosed with left heart hypoplasia syndrome, who underwent Norwood surgery at the age of 2 weeks, followed by restenosis of the distal anastomosis and balloon dilatation of neo-aorta restenosis with installation of a cobalt-chromium balloon-expandable stent (Andrastent XL) along with pararectal left-side access to the infrarenal section of the aorta at 11 months in order to reduce surgical risk and prepare for the next stage of correction (Glenn and Fontan operations).</p><p>Received 18 March 2020. Revised 10 April 2020. Accepted 17 April 2020.</p><p><strong>Funding:</strong> The study did not have sponsorship.</p><p><strong>Conflict of interest:</strong> Authors declare no conflict of interest.</p>