Cardiovascular Journal of Africa: Vol 31 No 1 (January/February 2020)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 31, No 1, January/February 2020 40 AFRICA
Echocardiographic left atrial remodelling and determinants
of left atrial size in the early phase of high blood pressure:
a comparative cross-sectional study in Douala, Cameroon
Armelle Corrine Simo Gounoue, Anastase Dzudie Tamdja, Simeon-Pierre Choukem, Hamadou Ba,
Sidick Mouliom Aboubakar, Archange Nzali, Marie Patrice Halle, Clovis Nkoke, Benjamin Momo Kadia,
Martin Hongieh Abanda, Chris Nadege Nganou, Marcel Kenfack Abzabji, Samuel Kingue
Abstract
Background: Left atrial remodelling (LAR) has been described
in Western populations with chronic hypertension and is asso-
ciated with a higher risk of adverse cardiovascular events.
Although hypertension tends to occur earlier and is more
severe in sub-Saharan Africa than in more developed nations,
LAR and its associated factors in these African hypertensive
subjects have been poorly elucidated.
Objectives: To assess left atrial structural remodelling in black
hypertensive patients and determine factors associated with
left atrial size.
Methods: This was a cross-sectional, comparative study
carried out in two tertiary hospitals in Douala, Cameroon
over a period of three months. Fifty-two patients, either newly
diagnosed with hypertension or known hypertensives treated
for less than a year, were consecutively recruited. These
patients were matched (unpaired matching) for age and
gender to 40 randomly selected healthy subjects. The poste-
rior–anterior diameter indexed to body surface area (BSA),
volume indexed to BSA, and longitudinal and transverse
diameters of the left atrium (LA) were measured using trans-
thoracic echocardiography, in accordance with the American
Society of Echocardiography guidelines. LAR was defined
as increase in LA size, characterised by LA volume ≥ 34 ml/
m2. Early morning urine was analysed for microalbuminuria
using urine strips to obtain spot albumin/creatinine ratio.
Data were analysed using SPSS version 23 and statistical
significance was set at p < 0.05.
Results: The gender distribution and mean age were similar
between the two groups. Hypertensive patients had signifi-
cantly higher mean body mass index, left ventricular mass
and an altered diastolic function. They also had significantly
higher LA longitudinal diameter (50.0 vs 47.4 mm; p = 0.045),
surface area (17.9 vs 15.5 cm2; p = 0.003) and volume (52.4
vs 43.8 ml; p = 0.002) compared to the non-hypertensive
counterparts. Fourteen patients (26.9%) had LA enlargement
compared to one (2.5%) in the non-hypertensive group (odds
ratio = 9.78, CI: 2.67–35.8, p < 0.0001). Diastolic dysfunction
(p = 0.008) was the only independent predictor of LA size in
the hypertensive subjects. Microalbuminuria did not signifi-
cantly correlate with LA size.
Conclusion: Our study shows evidence of LAR in newly diag-
nosed black African patients with hypertension, characterised
by an increase in the LA length, surface area and volume.
Future studies are warranted to better elucidate the biological
mechanisms underlying the link between the early phase of
hypertension and LAR, as well as its prognostic implications
in our population.
Keywords: hypertension, left atrium, remodelling, SSA
Submitted 11/1/19, accepted 31/7/19
Published online 9/9//19
Cardiovasc J Afr 2020; 31: 40–46
DOI: 10.5830/CVJA-2019-046
Hypertension is an important public health challenge worldwide.1
In sub-Saharan African populations, hypertension tends to occur
at an earlier age than in more developed nations, is frequently
under-diagnosed, and is often severe and complicated at the time
of diagnosis.2-4
Faculty of Health Sciences, University of Buea, Buea,
Cameroon
Armelle Corrine Simo Gounoue, MD,
Anastase Dzudie Tamdja, MD, PhD, FESC
Simeon-Pierre Choukem, MD, PU-PH (Paris)
Faculty of Medicine and Biomedical Sciences, University
of Yaoundé I, Yaoundé, Cameroon
Anastase Dzudie Tamdja, MD, PhD, FESC
Hamadou Ba, MD
Chris Nadege Nganou, MD
Marcel Kenfack Abzabji, MD
Samuel Kingue, MD
Douala General Hospital, Douala, Cameroon
Anastase Dzudie Tamdja, MD, PhD, FESC
Simeon-Pierre Choukem, MD, PU-PH (Paris)
Sidick Mouliom Aboubakar, MD
Marie Patrice Halle, MD, DU, DES (Nephology)
Clinical Research Education, Networking and Consultancy,
Douala, Cameroon
Anastase Dzudie Tamdja, MD, PhD, FESC
Archange Nzali, MD, DU (Cardiology)
Armelle Corrine Simo Gounoue, MD,
Martin Hongieh Abanda, MD
Deido District Hospital, Douala, Cameroon
Archange Nzali, MD, DU (Cardiology)
Buea Regional Hospital, Buea, Cameroon
Clovis Nkoke, MD
Faculty of Epidemiology and Population Health and Centre
for Evaluation, London School of Hygiene and Tropical
Medicine, London, UK
Benjamin Momo Kadia, MD