Abstract
This research addressed the question of whether pulse transmission time to the ear (E‐PTT) serves as a satisfactory estimate of pre‐ejcction period (PEP) and whether the intracardiac or arterial components of pulse transmission times are correlated with hlood pressure. A median correlation of .86 was found for within‐suhject correlations between E‐PTT and PEP, and a correlation of .97 was found on trial means across subjects. Pulse transmission times to the ear and finger (measured from the Q‐wave) were substantially correlated with systolic but not diastolic blood pressure. PEP, the intracardiac component of pulse transmission time, was moderately correlated with systolic blood pressure, but the arterial components were not. It was concluded that E‐PIT estimates PEP in within‐subject comparisons, and that the association of the pulse transmission times with systolic blood pressure is by virtue of the fact that these intervals encompass PEP rather than the arterial components. It was further concluded that pulse transmission times more directly reflect sympathetic cardiac influences than they do blood pressure.