P85 Acute Systemic Inflammation Reduces both Carotid and Aortic Wave Reflection in Young Healthy Adults

DOI

10.2991/artres.k.191224.115How to use a DOI?

Abstract

Acute inflammation increases the risk of cardiac and cerebrovascular events, potentially associated with altered hemodynamic load. Wave reflection at the aorta and carotid artery can contribute to central hemodynamic load and provide insight into downstream changes in vascular tone. Acute inflammation may reduce wave reflection via downstream vasodilation, however, this is not firmly established and has only been investigated at the aorta.

Purpose: Explore the effect of acute inflammation on aortic and carotid hemodynamics and wave reflection.

Methods: Twenty-three young adults (26 ± 4 yrs, 22.7 ± 3.2 kg/m²) underwent vascular measures at baseline and 24 h following typhoid vaccine-induced inflammation. Aortic (estimated from radial) and carotid pressure waveforms were obtained via tonometry. Augmentation index and wave separation analyses (WSA) were used to assess wave reflection. Aortic stiffness was estimated from single-point pulse wave velocity (PWV). Carotid beta-stiffness and arterial diameters were assessed via ultrasound.

Results: Acute inflammation reduced aortic and carotid wave reflection at 24 h (See Table 1 AIx, Reflection index, p < 0.05). WSA did not reveal independent changes in forward or reflected wave magnitude, time to reflection, PWV, or beta-stiffness (p > 0.05). Brachial and carotid artery diameter increased from 3.79 ± 0.76 to 3.86 ± 0.76 mm (p = 0.055) and 6.44 ± 0.72 to 6.55 ± 0.69 mm (p = 0.04), respectively.

	Aortic				Carotid
	n	Baseline	24-h	p-value	Baseline	24-h	p-value
SBP, mmHg	23	104 ± 10	104 ± 8	0.88	107 ± 11	107 ± 10	0.98
DBP, mmHg	23	72 ± 8	71 ± 7	0.23	71 ± 8	70 ± 7	0.26
MAP, mmHg	23	86 ± 9	85 ± 7	0.31	86 ± 9	85 ± 7	0.29
Pulse pressure, mmHg	23	32 ± 6	33 ± 8	0.21	36 ± 7	37 ± 8	0.39
AIx, %	23	3 ± 10	−1 ± 10	0.04	−4 ± 15	−9 ± 16	0.04
AIx@75, %	23	−6 ± 12	−9 ± 12	0.048	−13 ± 15	−18 ± 15	0.09
Augmented pressure, mmHg	23	1 ± 3	0 ± 3	0.05	−2 ± 6	−4 ± 7	0.08
Pf, mmHg	22	30 ± 7	31 ± 7	0.40	34 ± 8	36 ± 12	0.07
Pb, mmHg	22	14 ± 3	13 ± 4	0.24	16 ± 3	15 ± 4	0.09
Reflection index, au	22	47 ± 8	44 ± 9	0.04	48 ± 11	43 ± 13	0.01
Time to reflection, ms	22	158 ± 16	161 ± 20	0.20	180 ± 25	185 ± 26	0.53

All data mean ± standard deviation. SBP, systolic blood pressure; DBP, diastolic blood pressure; MAP, mean arterial pressure; AIx, augmentation index; Pf, forward wave magnitude; Pb, reflected wave magnitude.

Conclusion: Acute inflammation reduces aortic and carotid wave reflection in young adults, potentially due to downstream vasodilation. Although reduced wave reflection can decrease cardiac workload, reduced wave reflection in the carotid may render the brain vulnerable to pulsatile blood flow. These findings may implicate changes in wave reflections are a contributing mechanism behind acute inflammation-induced cerebrovascular risk.

Copyright

© 2019 Association for Research into Arterial Structure and Physiology. Publishing services by Atlantis Press International B.V.

Open Access

This is an open access article distributed under the CC BY-NC 4.0 license (http://creativecommons.org/licenses/by-nc/4.0/).

TY  - JOUR
AU  - Elizabeth Schroeder
AU  - Wesley Lefferts
AU  - Thessa Hilgenkamp
AU  - Bo Fernhall
PY  - 2020
DA  - 2020/02/17
TI  - P85 Acute Systemic Inflammation Reduces both Carotid and Aortic Wave Reflection in Young Healthy Adults
JO  - Artery Research
SP  - S128
EP  - S128
VL  - 25
IS  - Supplement 1
SN  - 1876-4401
UR  - https://doi.org/10.2991/artres.k.191224.115
DO  - 10.2991/artres.k.191224.115
ID  - Schroeder2020
ER  -