Dedicated to 90th Anniversary of an electrocardiology theorist, professor Leonid Ivanovich Titomir

The article is dedicated to the 90 th anniversary of the birth of Professor Leonid Ivanovich Titomir, a prominent Russian scientist, specialist in theoretical electrocardiology, who for many years headed the laboratory of bioelectric information processing at the Institute for Information Transmission Problems of the Russian Academy of Sciences. The article highlights the life path of Professor L.I. Titomir, the range of his scientific interests. The main scientific results and achievements of the team led by him are reflected. Particular attention is paid to the contribution of L.I. Titomir to international scientific cooperation.