3.5 HEART RATE DEPENDENCE OF REGIONAL AND LOCAL AORTIC PULSE WAVE VELOCITY IN RATS AS A FUNCTION OF BLOOD PRESSURE

DOI

10.1016/j.artres.2017.10.035How to use a DOI?

Abstract

Background: Pulse wave velocity (PWV) is quantified by time difference of arrival of the blood pressure (BP) wave at two sites along the arterial bed (transit time; TT-PWV), or by combining measured arterial pressure and diameter using the Bramwell-Hill equation (BH-PWV). Besides the dependence of PWV on BP, TT-PWV also depends on heart rate (HR). The present study aimed to also quantify the dependence of BH-PWV’s on HR, as a function of diastolic BP (DBP).

Methods: Adult anaesthetised rats (n = 24) were randomly paced at 300–500 bpm, at 50-bpm steps. At each step, aortic TT-PWV (two pressure-tip catheters) and BH-PWV (pressure-tip catheter and ultrasound wall-tracking; abdominal aorta) were measured simultaneously, across a pharmacologically induced DBP range of 60–110 mmHg.

Data from 9142 heart beats was analysed using mixed-effects modelling.

Results: HR dependence of TT-PWV increased from 0.03 m/s/100 bpm at DBP = 60 mmHg to 0.06 m/s/100 bpm at DBP = 110 mmHg (both p ≤ 0.023). HR dependence of BH-PWV was 0.11 m/s/100 bpm at DBP = 60 and 85 mmHg, but paradoxically decreased to 0 at DBP = 110 mmHg (p = 0.686). This decrease in dependence is explicable in that standard BH-PWV uses an approximate derivative of pressure to diameter, which overestimates PWV with increasing pulse pressure (PP). PP decreases as HR increases, potentially causing a BH-PWV decrease with HR. This effect can be overcome by estimating the full pressure-diameter curve for each HR, and calculating the true derivative at DBP, yielding a BH-PWV that no longer shows significant HR dependence (p ≥ 0.076 at all DBPs).

Conclusions: BH-PWV and TT-PWV show a different HR dependence, affected by DBP.

Open Access

This is an open access article distributed under the CC BY-NC license.

TY  - JOUR
AU  - Bart Spronck
AU  - Isabella Tan
AU  - Koen Reesink
AU  - Dana Georgevsky
AU  - Tammo Delhaas
AU  - Alberto Avolio
AU  - Mark Butlin
PY  - 2017
DA  - 2017/12/06
TI  - 3.5 HEART RATE DEPENDENCE OF REGIONAL AND LOCAL AORTIC PULSE WAVE VELOCITY IN RATS AS A FUNCTION OF BLOOD PRESSURE
JO  - Artery Research
SP  - 54
EP  - 54
VL  - 20
IS  - C
SN  - 1876-4401
UR  - https://doi.org/10.1016/j.artres.2017.10.035
DO  - 10.1016/j.artres.2017.10.035
ID  - Spronck2017
ER  -