CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 2, March/April 2011
AFRICA
71
Cardiovascular and electrocardiographic changes in
Nigerians with a normal pregnancy
PO AKINWUSI, VO OBORO, RA ADEBAYO, AA AKINTUNDE, AO ADENIJI, IA ISAWUMI, MO BALOGUN,
TO OGUNGBAMIGBE
Summary
Introduction:
Pregnancy is associated with major haemody-
namic and cardiac changes, which can mimic or precipitate
cardiac diseases. There is a paucity of this kind of data
among pregnant Nigerian women. This study was aimed
at describing the cardiovascular and electrocardiographic
changes found among healthy pregnant Nigerian women.
Methods:
This was an age-matched control study of 69
consecutive normal pregnant and 70 healthy non-pregnant
controls. The study protocol included history, physical
examination and 12-lead electrocardiography.
Results:
Diastolic blood pressure
<
60 mmHg was signifi-
cantly commoner among pregnant subjects than controls
(64.7 vs 24.3%, respectively,
p
<
0.005). Mean heart rate was
higher among pregnant women (88.34
±
11.46 bpm) than the
controls (75.16
±
12.22 bpm,
p
=
0.020). Pregnant subjects
also had a higher proportion of left ventricular hypertrophy
(LVH) (10.2 vs 0%,
p
<
0.05) than non-pregnant controls.
Abnormal cardiac findings included a loud second heart
sound (P
2
), missed beats and systolic murmurs (41.2% in
pregnant subjects vs 12.9% in non-pregnant controls,
p
<
0.05). Negroid-pattern ST-segment elevation was commoner
among controls (24.3%) than pregnant subjects (2.9%,
p
<
0.005). Arrhythmias were rare among the study participants.
Conclusion:
Significant findings on examination were low
diastolic blood pressure and a systolic ejection murmur.
However, ECG changes showed a normal frontal-plane QRS
axis, normal PR interval, significantly rare normal Negroid-
pattern ST elevation, significant LVH based on Araoye RI
>
12 mm and a rarity of all forms of arrhythmias. These data
may help resolve some cardiac diagnostic difficulties during
pregnancy.
Keywords:
cardiovascular, electrocardiographic changes, normal
pregnancy, Nigeria
Submitted 1/3/10, accepted 22/4/10
Cardiovasc J Afr
2010;
21
: 71–75
DOI: CVJ-21.028
Pregnancy is a normal physiological phenomenon causing
major haemodynamic changes, including an increase in cardiac
output, as well as sodium and water retention.
1,2
In addition, these
haemodynamic changes can mimic and/or precipitate cardiac
diseases and cause diagnostic difficulties during pregnancy.
There is a paucity of data relating to cardiovascular (CV) and
electrocardiographic (ECG) changes in healthy pregnant women
in Nigeria, although the CV effects of pregnancy and associ-
ated ECG changes have been well documented outside Nigeria
and Africa. Some of the notable ones are symptoms of exercise
intolerance/left-sided heart failure, palpitations and syncope.
2,3
Associated physical findings that have been reported include
peripheral oedema and distended neck veins.
2
Auscultatory examinations at different stages of pregnancy
may reveal a loud first heart sound (S
1
) with exaggerated split-
ting, which may be mistaken for a fourth heart sound (S
4
) or
systolic click;
2
and a loud second heart sound (S
2
) with persistent
splitting that may simulate a loud P
2
.
2
The volume-overloaded
state and the augmented blood flow may produce a physiological
third heart sound (S
3
) and an ejection systolic murmur, respec-
tively.
3
ECG findings that have been reported include the QRS axis,
which could be normal,
2
right or left axis;
2,4
frequent sinus tachy-
cardia with accompanying shortened PR and QT intervals,
4
as
well as higher incidence of arrhythmias.
2
Also reported are small
Q waves and inverted P waves in lead III (abolished by inspira-
tion), increased R/S ratio in leads V
1
and V
2
, as well as sagging of
ST segments and inversion of or flat T waves in lead III.
5
This study was therefore undertaken to describe the CV and
ECG changes in normal pregnancy among Nigerian women
attending Ladoke Akintola University of Technology Teaching
Hospital, Osogbo, south-west Nigeria.
Methods
This was a cross-sectional, age-matched control study of 139
patients, comprising 69 consecutive healthy pregnant and 70
healthy non-pregnant patients at Ladoke Akintola University of
Technology Teaching Hospital, Osogbo, Osun state, south-west,
Nigeria. The study was carried out over a two-year period from
February 2006 to January 2008. Institutional ethical clearance
was obtained and all subjects gave informed consent.
All the patients were taken through a comprehensive study
protocol of history and physical examination by two cardiolo-
gists. A 12-lead resting ECG with a long rhythm strip of lead
Department of Medicine, Ladoke Akintola University
Teaching Hospital, Osogbo, Nigeria
PO AKINWUSI, MD,
AA AKINTUNDE, MD
Department of Obstetrics and Gynaecology, Ladoke
Akintola University Teaching Hospital, Osogbo, Nigeria
VO OBORO, MD
AO ADENIJI, MD
IA ISAWUMI, MD
Department of Medicine, Obafemi Awolowo University
Teaching Hospitals Complex, Ile-Ife, Nigeria
RA ADEBAYO, MD
MO BALOGUN, MD
Department of Pharmacology and Therapeutics, Ladoke
Akintola University Teaching Hospital, Osogbo, Nigeria
TO OGUNGBAMIGBE, MD
