4.1 ACUTE, SYMPATHETIC-INDEPENDENT INCREASES IN HEART RATE BY WAY OF CARDIAC PACING RAISES AORTIC AND BRACHIAL BLOOD PRESSURE WITH INCREASED CARDIAC OUTPUT AND ARTERIAL STIFFNESS

DOI

10.1016/j.artres.2013.10.019How to use a DOI?

Abstract

Objective. Whilst the effects of heart rate (HR) on the cardiovascular system have been studied cross-sectionally or during exercise, the effect of acute, sympathetic-independent changes in HR on arterial stiffness, cardiac output (CO), mean pressure (MAP) and total peripheral resistance (TPR) has not previously been studied.

Methods. Sixteen subjects (aged 70 to 79 years, 3 female) with in situ permanent cardiac pacemakers or implantable cardioverter defibrillators were studied. Each subject was paced in a random order at 60 to 100 beats per minute (bpm) in 10 bpm increments. At each heart rate, TPR and CO were derived from measured finger arterial pressure waveform (Finometer®). Brachial (b) and central aortic (c) systolic (SBP), diastolic (DBP), MAP, and aortic augmentation index (AIx) were determined by brachial cuff-based pulse wave analysis, and carotid-femoral pulse wave velocity (PWV) measured using a thigh cuff and carotid tonometry (SphygmoCor® XCEL). Aortic to brachial pulse pressure amplification (PPA) was calculated.

Results. All parameters except for TPR and cSBP changed significantly with HR (Table, data presented as mean ± sem). This indicated that HR-driven changes in MAP were due to increased CO, not changes in TPR. PWV showed an increase with increasing HR. However, this was not significant once corrected for changes in MAP (PWV_c, Table).

Conclusion. Acute, sympathetic-independent increases in HR through cardiac pacing raises CO, which in turn increases MAP and results in increased arterial stiffness.

	60 bpm	80 bpm	100 bpm	P
bSBP (mmHg)	127 ± 5	131 ± 4	133 ± 5	0.01
bDBP (mmHg)	69 ± 2	76 ± 2	83 ± 3	<0.001
cSBP (mmHg)	116 ± 4	118 ± 4	120 ± 4	0.51
cDBP (mmHg)	70 ± 2	76 ± 2	86±3	<0 .001
MAP (mmHg)	87 ± 2	94 ± 3	102 ± 4	<0.001
TPR (dyn.s/cm5)	1749 ± 276	1656 ± 227	1482 ± 137	0.14
CO (L/min)	5.0 ± 0.4	5.4 ± 0.4	5.8 ± 0.4	<0.001
PPA	1.26 ± 0.01	1.30 ± 0.02	1.50 ± 0.03	<0.001
AIx (%)	33 ± 3	31 ± 3	22 ± 3	<0.001
PWV (m/s)	9.5 ± 0.5	10.3 ± 0.5	11.1 ± 0.4	<0.001
PWVc (m/s)	10.3 ± 0.4	10.4 ± 0.4	10.4 ± 0.4	0.75

Data for 70 bpm and 90 bpm were measured and analysed but not shown

Open Access

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

TY  - JOUR
AU  - I. Tan
AU  - E. Barin
AU  - A.P. Avolio
AU  - M. Butlin
PY  - 2013
DA  - 2013/11/11
TI  - 4.1 ACUTE, SYMPATHETIC-INDEPENDENT INCREASES IN HEART RATE BY WAY OF CARDIAC PACING RAISES AORTIC AND BRACHIAL BLOOD PRESSURE WITH INCREASED CARDIAC OUTPUT AND ARTERIAL STIFFNESS
JO  - Artery Research
SP  - 166
EP  - 166
VL  - 7
IS  - 3-4
SN  - 1876-4401
UR  - https://doi.org/10.1016/j.artres.2013.10.019
DO  - 10.1016/j.artres.2013.10.019
ID  - Tan2013
ER  -