Kateřina Fialová

Frequency domain HRV analysis of ischemia manifestation at isolated rabbit hearts

The ischemia manifestation was analyzed using heart rate variability (HRV) parameters in frequency domain. Assessment of HRV was based on analysis of consecutive normal R-R intervals during 5 minutes interval in seven section of measured ECG: control period, ischemia I-III periods and reperfusion I-III periods. Seven rabbits were used for experiment.

Influence of ischemia on left ventricular depolarization in isolated rabbit hearts perfused according to Langendorff

The aim of this study was to search for relation between electrical activity recorded from whole isolated heart and simultaneously from one cell. The QRS complex of electrogram (ECG) corresponds to the depolarization of the ventricles. The depolarization propagation is shown by monophasic action potential (MAP) recorded at appointed place during experiment. Electrogram changes observed during ischemia should be accounted for changes on cellular level. MAPs and ECG were recorded simultaneously. The activation time (AP), defined as distance from the earliest QRS deflection to MAP upstroke, changes with duration of ischemia. The excitement propagation and conduction in ischemic heart takes longer time in comparison to non-ischemic myocardium.