The “life” of an idiom, the frequency of its use in speech is limited by the time frame: those elements that were actively used a hundred years ago are gradually disappearing from the lexicon of a modern person. Therefore, it seemed to us relevant and important, both in theoretical and practical aspects, to develop a methodology for identifying only those phraseological units that are used in the live speech of modern native speakers and are necessary for communication in the Russian-speaking environment today. The study was conducted on the material of idioms with somatic components, including the word heart. We emphasize that the object of our analysis were only phraseological units used in oral speech. The work consisted of 2 stages: at the first stage, a general group of phraseological units with a heart component was identified, a component analysis of the dictionary definition of the word heart was carried out, and phrase-forming semes were identified. Each of these semes motivated a certain subgroup of phraseological units with heart component as part of the general group. At the second stage of the study, we conducted a survey of 100 informants belonging to different age groups. Analysis of the results made it possible to single out a group of 25 active speech idioms units that is relevant for a modern native speaker of the language. The proposed methodology is universal, it can be applied to any other group of phraseological units, so it could allow to determine what kind of idiomatic material should be included in the Russian as a foreign language course for active assimilation.