Exploratory insights from the right-sided electrocardiogram following prolonged endurance exercise

Abstract

Background: Prolonged strenuous exercise has a profound effect on cardiac function. The right heart may be more susceptible to this imposition; yet, right-sided chest leads have not been utilised in this setting. Methods: Thirty highly trained athletes at the 2014 Western States 100-mile Endurance Run from Squaw Valley to Auburn, California (body mass 68 ± 12 kg, age 45 ± 10 years, 57 ± 15 miles per week) were recruited for the study. Pre- and post-race, a right-sided 12-lead ECG was obtained and data were extracted for P, R and S waves, J point, ST segment and T wave amplitude. Data were compared using Students T-test and statistical significance set as P < .05. Results: There was a significant increase in P wave amplitude (29%) and QTc interval (4%) pre- to post-race from standard 12-lead ECG. From the right-sided12-lead ECG, a 23% (P = .01) and 38% (P = .03) increase in J point amplitude in V1R and V2R and a 22% (P = .05) increase in ST segment integral in V2R and V3R were evident. T wave inversion was evident in leads V2R–V6R in 50–90% of athletes, respectively. Close examination revealed marked heterogeneity in individual ECGs. Conclusions: Completion of a 100-mile ultra-marathon resulted in significant changes in the right-sided ECG alongside more marked responses in specific individuals. P wave, ST segment and T wave changes post-race are indicative of acute exercise-induced right heart electrical adaptation.

Keywords:

• Electrocardiogram
• right-sided ECG
• prolonged endurance exercise

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

We would like to thank the Western States Endurance Run Foundation for the funding that allowed us to undertake this research.