Two widely used markers of cardiac repolarization time are the time RT$_{tap}$ of minimum derivative during the downstroke of the transmembrane action potential (TAP) and the time RT90$_{tap}$ when the TAP reaches 90\% of its resting value. These two markers are generally taken as the gold standards for comparison with other markers assessing repolarization time from the T wave of the unipolar electrogram.The results show a high correlation between the extracellular and transmembrane markers, irrespective of T wave polarity. However, the extracellular markers may be locally inaccurate in estimating the repolarization sequence and large discrepancies may ensue when they are compared with transmembrane markers. As a consequence, the spatial distribution of activation-recovery intervals (ARI) is not always an accurate estimate of the spatial distribution of action potential durations (APD).
A reliability analysis of cardiac repolarization time markers
SCACCHI, SIMONE;COLLI FRANZONE, PIERO;
2009-01-01
Abstract
Two widely used markers of cardiac repolarization time are the time RT$_{tap}$ of minimum derivative during the downstroke of the transmembrane action potential (TAP) and the time RT90$_{tap}$ when the TAP reaches 90\% of its resting value. These two markers are generally taken as the gold standards for comparison with other markers assessing repolarization time from the T wave of the unipolar electrogram.The results show a high correlation between the extracellular and transmembrane markers, irrespective of T wave polarity. However, the extracellular markers may be locally inaccurate in estimating the repolarization sequence and large discrepancies may ensue when they are compared with transmembrane markers. As a consequence, the spatial distribution of activation-recovery intervals (ARI) is not always an accurate estimate of the spatial distribution of action potential durations (APD).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
