4.1.1. Study Design
Subjects were recruited from March 2019 to March 2020 from the Cardiology Clinic of the First Sechenov Moscow State Medical University, Moscow, Russia. Laboratory and instrumental procedures, as well as the training course, were conducted in the same clinic. The study was approved by the ethical committee of the I.M. Sechenov First Moscow State Medical University (Local Ethical Protocol No. 05-19 10.04.2019) and was performed according to the ethical standards based on the Declaration of Helsinki—Ethical Principles for Medical Research Involving Human Subjects. Written informed consent was obtained from all trial participants. The study was registered at ClinicalTrials.gov (NCT04791397, protocol identifier A0519).