Аннотация:The paper presents the results on investigations and development of multichannel waveguide CO2 laser with diffusion cooling of active medium excited by discharge of audio-frequency alternating current. The description of high-power single-mode CO2 laser with average beam power up to 1 kW is presented. The results of measurement of the laser basic parameters are offered, as well as the outcomes of performances of the laser head with long active zone, operating in waveguide mode. As an example of application of these lasers, various capabilities a description of the developed medical system 'Genom' used in the transmyocardial laser revaslularization (TMLR) procedure and clinical results of the possibilities of the TMLR in the surgical treatment are presented.