Hemodynamic significance of ventricular ectopic beats: the impact of coupling intervals

The aim of the study was to evaluate the effect the impact of the coupling interval (CI) of ventricular ectopic beats (VEB) on their hemodynamic properties. Methods . The hemodynamic properties of VEBs were studied using the example of ventricular parasystoles with typical manifestations. The hemodynamic properties of VEB were studied using the example of ventricular parasystoles with typical manifestations (significant differences in CI, “multiplicity,” presence of “fusion” QRS complexes) in two female patients without structural heart abnormalities, each having more than 10000 monomorphic VEB per day. The research method involved measuring blood pressure (BP) with each heartbeat. The duration of the study, over the course of which systolic BP (SBP), diastolic BP (DBP), and pulse BP (PBP) were recorded, was 15 minutes. Results . The hemodynamic properties of VEB were determined by assessing the correlation between the duration of the CI and the SBP, DBP, and PBP of the VEB. The SBP, DBP, and PBP values showed a highly significant correlation with the CI of the VEB: the shorter the CI, the lower the SBP and PBP, and the higher the DBP. The DBP was more strongly dependent on the CI than the SBP, and the PBP was even more dependent. The relationship between the DBP and CI of the VEB was linear, whereas the relationship between the SBP and PBP with the CI of the VEB was nonlinear: it was more pronounced with short (decreased BP) and long CIs (increased BP). There was also a highly significant correlation between the PBP and SBP of the VEB, as well as between the PBP and DBP of the VEB: the PBP of the VEB was influenced by both the decrease in SBP and the increase in DBP, but more so by the decrease in SBP. Conclusions . As the CI of VEB shortens, its SBP decreases and DBP increases. The relationship between DBP and CI is linear, whereas the relationships between SBP and PBP with CI are nonlinear: they are more pronounced with short (decreased BP) and long (increased BP) CIs. The PBP of VEB depends on both the decrease in SBP and the increase in DBP, but it is more strongly associated with SBP.