Exercise stress testing and an electromechanical S wave of the electrocardiogram. Does the S-wave voltage change...

A new view of the electrocardiogram, first proposed by Posel and arising from Craib's travelling dipole concept, predicts an electromechanical relationship between S-wave amplitude changes and cardiac mechanical function changes. In an attempt to determine whether the S-wave voltage changes with increasing work rate, 10 male subjects were tested at rest and at maximum exercise. A statistically significant increase in the S wave occurred with increased mechanical work. The theoretical prediction of an electromechanical S wave is thus validated and a request is extended to other workers to verify or refute its existence.