Changes in Electrocardiographic Parameters in Males of the European North as Markers of Climate- and Age-Related Effects

Electrocardiographic (ECG) amplitude- and time-related characteristics were determined in 20- to 59-year-old healthy male residents of the European north (the zone from 60° to 70° N). They were found to display increased amplitudes of some ECG waves, as well as prolonged P waves and R–R intervals, as compared to residents of warmer regions. In men, with age, the electrical axis of the heart shifts leftward and the heart tends to rotate counterclockwise about its longitudinal axis. Increased amplitudes of the P and S waves, as well as decreased amplitudes of theQ, R, and T waves, a lower position of the ST segment relative to the isoelectric line, and a prolongation of the P wave; the P–Q, Q–T, and R–R intervals; and the ST segment were observed in most of the leads. A regional variant of the age-specific amplitude- and time-related characteristics of the ECG is suggested for healthy male residents of the north.