Am J Physiol Heart Circ Physiol. 2022 Oct 7. doi: 10.1152/ajpheart.00454.2022. Online ahead of print.
ABSTRACT
There are numerous sex-related differences in cardiac electrophysiology and arrhythmia propensity but very little knowledge about the reasons. Difference in body size has been proposed as one reason and was tested in this study of >20 cardiac electrophysiology parameters in 319 (158 women) apparently healthy 50-64 years old subjects from a randomly enrolled population sample, the SCAPIS pilot study (Swedish CArdio-Pulmonary bioImaging Study), using Frank vectorcardiography. We studied conventional conduction intervals, parameters reflecting electrical heterogeneity (dispersion) in the ventricles, QRS- and T-vector directions, spatial QRS-T angles, and T-vector loop morphology. Body surface area (BSA; two methods) and lean body mass (LBM), both estimated from body weight and height, were used as body size parameters. According to multivariable linear regression analysis adjusted for sex, there was no association between electrophysiological parameters and body size apart from QRS duration and QRSarea. In conclusion, most electrophysiological parameters assessed completely non-invasively and showing statistically significant differences between women and men on the group level show no association with BSA or LBM. Scaling (indexing) the electrophysiological parameters for body size parameters are therefore not an option. As a consequence, the explanation for the sex-related electrophysiological differences should be sought along other lines.
PMID:36206051 | DOI:10.1152/ajpheart.00454.2022