Cardiovascular Journal of Africa: Vol 31 No 6 (November/December 2020)

58 / 64

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 31, No 6, November/December 2020 338 AFRICA
6. Choudhury T, West NE, El-Omar M. ST-elevation myocardial infarc-
tion. Clin Med (Lond) 2016; 16(3): 277–282.
7. Januzzi JL. Troponin and BNP use in COVID-19. Cardiol Mag. Am
Coll Cardiol. Available at: https://
articles/2020/03/18/15/25/troponin-and-bnp-use-in-covid19. Accessed
Mar 23, 2020.
8. Driggin E, Madhavan VM, Bikdeli B, et al. Cardiovascular considera-
tions for patients, health care workers, and health systems during the
coronavirus disease 2019 (COVID-19) pandemic. J Am Coll Cardiol
2020. [Epub ahead of print].
9. American College of Cardiology. Troponin and BNP use in COVID-
19. Available at:
cles/2020/03/18/15/25/troponin-and-bnp-use-in-covid19.
10. Huang C, Wang Y, Li X, et al. Clinical features of patients infected with
2019 novel coronavirus in Wuhan, China. Lancet 2020; 395: 497–506.
11. Zeng J, Huang J, Pan L. How to balance acute myocardial infarc-
tion and COVID-19: the protocols from Sichuan Provincial People’s
Hospital. Intensive Care Med Mar 11, 2020. [Epub ahead of print].
12. Wang D, Hu B, Hu C, et al. Clinical characteristics of 138 hospitalized
patients with 2019 novel corona-virus-infected pneumonia in Wuhan,
China. J Am Med Assoc Feb 7, 2020. [Epub ahead of print].
13. Shi S, Qin M, Shen B, et al. Association of cardiac injury with mortality
in hospitalized patients with COVID-19 in Wuhan, China. J Am Med
Assoc Cardiol March 25, 2020. [Epub ahead of print].
14. Zhou F, Yu T, Du R, et al. Clinical course and risk factors for mortality
of adult in patients with COVID-19 in Wuhan, China: a retrospective
cohort study. Lancet 2020; 395(10229): 1054–1062.
15. Li B, Yang J, Zhao F, et al. Prevalence and impact of cardiovascular
metabolic diseases on COVID-19 in China. Clin Res Cardiol Mar 11,
2020. [Epub ahead of print].
Aspirin use best for those with high coronary calcium, low risk of bleeding
An X-ray test, commonly used to assess hardening of the
arteries, could help doctors decide whether the benefits of
taking aspirin to prevent a first heart attack or stroke outweigh
the risks of bleeding from its use, UT Southwestern research
suggests. The findings could give doctors and patients more
concrete guidelines for making this important decision.
Due to its anti-clotting properties, aspirin is widely
prescribed as a preventative measure to patients who have
already had cardiovascular events, such as a heart attack
or ischaemic stroke. However, aspirin’s role in primary
prevention – averting first heart attacks and strokes – has
been unclear, explains study leader Dr Amit Khera, professor
of internal medicine.
After decades of commonly prescribing aspirin for primary
prevention, recent guidelines from the American Heart
Association (AHA) and American College of Cardiology
(ACC) recommend more select use for those with the highest
risk of cardiac events due to the increased risk of bleeding.
‘We used to say for aspirin, generally yes, occasionally no,’
Khera says. ‘With these new guidelines, we’ve flipped that
on its head and are saying that we should not use aspirin for
most people in primary prevention.’
However, he adds, ‘it’s been unclear how to select
which patients might still benefit most from aspirin
therapy, taking into account the risk of bleeding. We
need tools to find that sweet spot where aspirin is most
beneficial and offsets the associated risks,’ he says.
In the study, Khera and his colleagues looked to a diagnostic
test – coronary artery calcium (CAC) scanning – to see if
it could help doctors make this important decision. CAC
scanning, a CT scan that scores the amount of calcium that
lines the heart’s arteries, is commonly performed to detect
hardening of the arteries and risk of a heart attack or stroke.
The researchers gathered data from the Dallas Heart
Study, an ongoing study that tracks the development of
cardiovascular disease in more than 6 000 adults in Dallas
County. Initially, participants were invited to three visits
for the collection of health and demographic information,
laboratory samples and various imaging studies, including
CAC scanning. These volunteers were then followed for 12
years on average to track those who had heart attacks, died
from heart disease, or had a non-fatal or fatal stroke – medical
problems collectively called atherosclerotic cardiovascular
disease – and/or who had a bleeding event that caused
hospitalisation or death.
The researchers used data from 2 191 participants with
a mean age of 44 years who had CAC scans and follow-up
information available. About 57% were female and 47% were
black.
Overall, about half of the participants had a CAC score
of 0, suggesting little to no calcium build-up in their arteries.
About 7% had a CAC score of more than 100, suggesting heavy
calcium build-up. The rest had values in the middle (1–99).
When Khera and his colleagues examined the rates
of atherosclerotic cardiovascular disease (ASCVD) and
bleeding in the study group, they found that both events
increased in a graded fashion as CAC scores rose. However,
when they used statistical modelling to see how many of the
ASCVD events may have been prevented by aspirin use –
based on values gleaned from a recent meta-analysis that
informed the AHA and ACC guidelines – they found that
aspirin’s benefits only outweighed its risks for those with
CAC scores above 100. For this group, the risk of ASCVD
was about 15-fold and the bleeding risk about three-fold of
those with a CAC score of 0.
Yet, this effect only held true for those whose inherent risk
for bleeding was already low, Khera says, meaning that in
practice, as mentioned in the guidelines, if someone has had
prior significant bleeding episodes, risk factors for bleeding,
or was on medications that increase bleeding, they should
not take aspirin for primary prevention regardless of their
CAC score.
Together, Khera says, the findings reinforce new guidelines
suggesting that aspirin for primary prevention is only
appropriate for select patients and that CAC scanning can
help doctors and patients make that decision.
‘Aspirin use is not a one-size-fits-all therapy,’ says Khera,
who holds the Dallas Heart Ball chair in hypertension and heart
disease. ‘CAC scanning can be a valuable tool to help us tailor
care to help more patients avoid a first heart attack or stroke.’
Source: Medical Brief 2020