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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 31, No 2, March/April 2020
58
AFRICA
Cardiovascular Topics
Endothelial dysfunction in HIV-positive patients with
acute coronary syndromes
Ahmed Vachiat, Therese Dix-Peek, Raquel Duarte, Pravin Manga
Abstract
Aim:
This study investigated endothelial function in
HIV-positive patients with acute coronary syndrome (ACS).
Flow-mediated dilatation, pulse-wave velocity, carotid inti-
ma–media thickness and endothelial biomarkers were used to
non-invasively investigate endothelial dysfunction.
Methods:
Twenty HIV-positive patients with ACS (HIV+/
ACS) were compared to 20 HIV-negative patients with ACS
(HIV-/ACS) and 20 HIV-positive patients without ACS
(HIV+/no ACS).
Results:
Endothelial function measured by flow-mediated
dilatation (FMD) was similar in both the HIV+/ACS (5.2;
IQR 1.4–13.4%) and HIV-/ACS groups (3.7; IQR 2.3–4.4%)
(
p
=
0.78). Arterial stiffness, measured by pulse-wave velocity
(PWV) was low in all three cohorts. Carotid intima–media
thickness (CIMT) was also low in all three cohorts. The
vascular cellular adhesion molecule-1 (VCAM-1) levels in
HIV-positive patients with and without ACS were signifi-
cantly higher than in the HIV-/ACS cohort (
p
=
0.033 and
0.024, respectively).
Conclusion:
Non-invasive investigations such as FMD, CIMT
and PWV did not identify patients with HIV who were at
high risk of ACS. Endothelial biomarkers may be more useful
markers to identify HIV-positive patients who have endothe-
lial dysfunction and increased risk of ACS.
Keywords:
HIV, acute coronary syndromes, endothelial dysfunc-
tion, flow-mediated dilatation, pulse-wave velocity, carotid inti-
ma–media thickness
Submitted 18/4/18, accepted 8/7/19
Published online
Cardiovasc J Afr
2020;
31
: 58–64
www.cvja.co.zaDOI: 10.5830/CVJA-2019-040
There are approximately 37 million people living with human
immunodeficiency virus (HIV) worldwide, of whom 70% live
in sub-Saharan Africa.
1,2
Increased life expectancy globally as
a result of better access to combination antiretroviral therapy
(cART) and high levels of traditional cardiovascular disease risk
factors have increased the prevalence of ischaemic heart disease
(IHD) in this population.
3,4
Developed countries generally have
an older HIV-positive population with a higher IHD risk profile
compared to a younger HIV-positive population in the developing
world with a lower IHD risk profile.
5
Developed nations have
substantial data on IHD in HIV-positive populations while there
is a paucity of data from developing regions.
The endothelium lines the internal surface of blood vessels
and is responsible for vascular homeostasis, such as maintenance
of vascular tone and non-thrombotic vascular surfaces, as well as
immunomodulation. With the onset of endothelial dysfunction,
the vasculature is predisposed to vasoconstriction, leukocyte
adherence, platelet activation, pro-oxidation, thrombosis,
impaired coagulation and vascular inflammation.
6
Endothelial
dysfunction has therefore been identified as a key step in
promoting atherogenesis, and is well described to be an early
predictor of future cardiovascular events in patients both with
and without established cardiovascular disease.
7-9
Endothelial function can be measured in many different ways.
The more common technique and one that is well validated is the
non-invasive measurement of endothelial function, which relies
on high-resolution ultrasound of the brachial artery.
6
Another
approach is by measuring endothelial biomarkers.
Endothelial biomarkers, such as cellular adhesion molecules,
are either present on the surface of endothelial cells or are
expressed on endothelial cells in response to certain stimuli.
Endothelial biomarkers include the selectins (E-selectin,
P-selectin, L-selectin), vascular adhesion molecule-1 (VCAM-
1) and intercellular adhesion molecule-1 (ICAM-1), which are
involved in leukocyte rolling, adhesion and trans-endothelial
migration into sub-intimal spaces.
6
There is evidence that these
cellular adhesion molecules can be considered reliable biomarkers
for the development and severity of atherosclerosis and could
add to the predictive value of the classical risk factors for IHD in
HIV-negative populations.
6,10
There are insufficient data that this
can be applied in HIV-positive patients, particularly those with
acute coronary syndromes (ACS).
Endothelial function has been studied in HIV-positive patients
since the onset of the epidemic.
11
There appears to be an intricate
interplay between endothelial function and inflammation, as
markers such as VCAM-1 and ICAM-1 are elevated in patients
early after HIV infection.
12
The mechanism of endothelial
Division of Cardiology, Department of Medicine, Faculty
of Health Sciences, University of the Witwatersrand,
Johannesburg, South Africa
Ahmed Vachiat, MB BCh, MMed, FCP (SA), Cert Cardiology (SA),
PhD,
ahmedvachiat@gmail.comPravin Manga, MB BCh, FCP (SA), PhD
Molecular Biology Laboratory, Department of Internal
Medicine, Faculty of Health Sciences, University of the
Witwatersrand, Johannesburg, South Africa
Therese Dix-Peek, MSc
Raquel Duarte, PhD