This article presents the main algorithms and the methodology for the development of the evaluation criteria and the results of the work of the program environment developed for evaluation and analysis of the electrocardiographic signals in the preventive control of clinically healthy people after emotional or physical stress for the purpose of diagnosing of current disorders in the cardiac activity. The presented structure combines a new approach to building an electronic system for assessing individual medical information from the real life of healthy people and a specific method for analyzing the results. The purpose of preventive control is to preserve human health through early and timely assessment of its current health status.