Experimental validation of extended access to the interventricular septum in the surgical treatment of hypertrophic cardiomyopathy

Background . Currently, there has been an increase in the number of reported cases of hypertrophic cardiomyopathy, probably due to improvements in diagnostic techniques, examination methods, and an increase in the total number of patients. The gold standard for surgical treatment remains open transaortic myectomy, which has a number of disadvantages, such as limited visualization, in some cases leading to the inability to perform radical resection of hypertrophied muscles. The need to expand the scope of resection, improve the quality of visualization, and reduce the frequency of disease recurrence determines the relevance of developing a new technique for accessing the interventricular septum. Objective . To investigate the possibilities of new extended access to the interventricular septum with effective repair of the aortic and mitral valves in the surgical treatment of hypertrophic cardiomyopathy in an experimental setting. Design and methods. From March 2017 to May 2023, two series of experiments have been conducted at the Center for Preclinical and Translational Research of the Almazov National Medical Research Centre to investigate extended access to the interventricular septum with repair of the aortic and mitral valves. Results . The developed extended access to the interventricular septum demonstrated its effectiveness on experimental anatomic models. The possibility of effective repair of the aortic valve commissure and the anterior mitral valve leaflet after the extended access without a significant impact on the geometry of the fibrous annuli and the function of these valves has been proven. Conclusion . The developed extended access allows for improved visualization of the interventricular septum in patients with a narrow fibrous ring of the aortic valve, mid-ventricular and apical forms of hypertrophic cardiomyopathy. Restoration of the valve apparatus (mitral and aortic valves) using the new access is possible and effective. Based on the results of this study it seems promising to conduct preclinical studies (in vivo on animals). And in the future — implementation in clinical practice in certain groups of patients.