Electrocardiogram R-wave is an Unreliable Indicator of Pulse Wave Initialization

Variability of R-R, P wave-to-R wave, and R wave-to-T wave intervals.

We analyzed the effect of changing posture from supine to standing on the variability of R-R, P-R, and R-T intervals in 10 healthy volunteers using power spectral analysis. An electrocardiogram and respiratory trace were recorded before and after posture change. Variability in the P-R and R-T intervals was much less than in the R-R interval and demonstrated a lower low-frequency (LF)-to-high-fr...

Pulse Wave Analysis and Pulse Wave Velocity

momanometer that provides arterial pressures (brachial systolic and diastolic pressure) is coming under question. The concerns extend well beyond the familiar issue of “white coat” hypertension, home and 24-h blood pressure recordings, and the phase-out of mercury based instruments. These concerns relate to the inaccuracy of all cuff devices for measuring pressure within the brachial artery, th...

The enigmatic sixth wave of the electrocardiogram: the U wave.

The U wave is the last, inconstant, smallest, rounded and upward deflection of the electrocardiogram. Controversial in origin, it is sometimes seen following the T wave with the TU junction along the baseline or fused with it and before P of the following cycle on the TP segment. In this review we will study its temporal location related to monophasic action potential, cardiac cycle and heart s...

Pulse wave analysis with diffusing-wave spectroscopy.

Hypertension is a major risk factor for cardiovascular disease and thus at the origin of many deaths by e.g. heart attack or stroke. Hypertension is caused by many factors including an increase in arterial stiffness which leads to changes in pulse wave velocity and wave reflections. Those often result in an increased left ventricular load which may result in heart failure as well as an increase...

The pulse wave velocity as an early indicator of atherosclerosis in diabetic subjects.