Cardiovascular research
-
Cardiovascular research · Jun 2003
Comparative StudySex differences in the rate dependence of the T wave descending limb.
The interval from the peak to the end of the T wave (TpTe) has been proposed to reflect the heterogeneity of action potential durations within the ventricular wall. Several studies have previously described TpTe to be independent of heart rate, which contradicts the in vitro observation of marked changes in transmural repolarisation heterogeneity due to cycle length changes. Because of this inconsistency, we investigated heart rate related changes of TpTe interval. ⋯ There is a marked rate dependence of TpTe interval, which differs between women and men. The finding is consistent with the TpTe interval being an approximate surrogate of the intraventricular repolarisation gradient. The rate dependent increase in transmural repolarisation heterogeneity might be one of the reasons for the increased propensity of torsades de pointes in women.