Cardiovascular Journal of Africa: Vol 26 No 5 (September/October 2015)

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CARDIOVASCULAR JOURNAL OF AFRICA • Vol 26, No 5, October/November 2015 AFRICA 11
11Department of Medicine, University College Hospital Ibadan,
Ibadan, Nigeria
12Ministry of Health, Umuahia, Nigeria
13Non-Communicable Diseases Unit, South African Medical
Research Council, South Africa
Background: Pulmonary hypertension (PH) is a major public
health issue worldwide. Despite improvements in understanding
PH and the development of novel therapies, the condition is still
diagnosed at an advanced stage, leading to a poor quality of life
and survival. We assessed the diagnostic utility of a standard
12-lead ECG for PH in resource-limited settings.
Methods: Sixty-five patients diagnosed with PH from the
multicentre Pan-African Pulmonary Hypertension Cohort
(PAPUCO) study were compared to 285 heart disease-free
subjects from the Heart of Soweto study. Prevalence, sensitiv-
ity, specificity, and positive and negative predictive values of
ECG parameters indicative of PH and right heart strain were
calculated.
Results: Of the 65 patients, 46% had PH due to left heart disease,
31% had pulmonary arterial hypertension and 22% had PH
due to lung disease and/or hypoxia. Compared to the control
group, all abnormalities were more frequent in the PH cohort.
The most prevalent ECG abnormalities (cases vs control) were:
pathological Q wave (47.7 vs 6.7%, p < 0.05), left ventricular
hypertrophy (38.5 vs 9.8%, p < 0.05) and p-pulmonale (36.9 vs
20.7%, p < 0.05). No patient had a completely normal ECG, as
opposed to 15% in the control group. The sensitivity of ECG
criteria for right heart strain ranged between 6.2 and 47.7%,
while specificity ranged between 79.3 and 100%. The negative
predictive value ranged between 81.5 and 88.9%. The positive
predictive value was lowest at 25% for RBBB and QRS right-
axis deviation (≥ 100°), and highest at 100% for QRS axis ≥
+100° combined with R/S ratio ≥ 1 or R in V1 > 7 mm.
Conclusion: ECG abnormalities were common among patients
with PH but were not specific, and furthermore, those relating
to right heart strain were rather less frequent. ECG patterns
focusing on the R and S amplitude in the V1 and right-axis
deviation had good negative predictive values for PH, but due
to a high prevalence of ECG abnormalities, this should be
interpreted with caution. Until further studies, other tools are
needed for screening PH.
LEFT VENTRICULAR DIASTOLIC FUNCTION IN NIGE-
RIAN CHILDREN WITH HOMOZYGOUS SICKLE CELL
ANAEMIA USING ECHOCARDIGRAPHY
Bamigboye-Taiwo Olukemi Tolulope*, Akintunde Okeniyi
John1, Omokhodion Samuel2
*Federal TeachingHospital, Ido-Ekiti;Department of Paediatrics,
FETHI, Ido-Ekiti, Ekiti, Nigeria;
1Department of Paediatrics and Child Health, Obafemi
Awolowo University Teaching Hospitals Complex, Ile- Ife,
Osun State, Nigeria
2Department of Paediatrics, University College Hospital, Oyo
State, Ibadan, Nigeria
Introduction: Sickle cell anaemia (SCA) remains the most preva-
lent and arduous inherited disease in Nigeria. Various adverse
cardiovascular impacts have been attributed; however, a dearth
of literature persists about its impact on diastolic functioning
among children.
Objective: Determination of left ventricular (LV) diastolic func-
tion in children with SCA in steady state and comparison with
apparently healthy haemoglobin type AA controls.
Methods: Observational, case–control, cross-sectional study of
50 subjects aged ≤ 15 years and 50 age- and gender-matched
controls to determine and compare E-wave and A-wave veloci-
ties (m/s), E/A ratio and deceleration time (ms) using 2-D
guided Doppler echocardiography. Body surface areas (BSA)
and haematocrits were also assessed.
Results: Subjects had a significantly higher E-wave velocity
(1.08 vs 0.94 m/s, p = 0.0011) and A-wave velocity (0.58 vs 0.52
m/s), p = 0.0000135) than controls. Slightly higher E/A ratio and
longer deceleration times were observed in subjects but without
statistical significance (p = 0.481 and p = 0.334, respectively).
E- and A-wave velocities in subjects did not correlate with age
or BSA unlike in controls, which showed negative correlations.
There was however a significant negative correlation between
haematocrit and the A-wave velocity and E/A ratio of subjects.
Conclusion: Even in steady state, children with SCA had rela-
tively early as well as late diastolic filling. These indices did
not correlate with age or BSA. Haematocrit showed significant
correlation with late diastolic filling.
A DECREASE IN INVASIVE AND NON-INVASIVE GROUP
A STREPTOCOCCAL INFECTION IN SOUTH AFRICA,
2003–2013
Barth Dylan*, Engel Mark, Whitelaw Andrew1, Mayosi Bongani
University of Cape Town, Groote Schuur Hospital, Cape Town,
South Africa;
1Stellenbosch University
Background: Group A Streptococcus (GAS) is of enormous
burden in developing countries and continues to be a major cause
of premature death and morbidity. The aim of this population-
based study is to describe the incidence and epidemiological char-
acteristics of Group A streptococcal infection in South Africa.
Methods: We performed a retrospective study of cases of
invasive and non-invasive GAS isolates from January 2003 to
December 2013 from the National Health Laboratory Service
(NHLS) corporate data warehouse electronic database. Invasive
GAS was defined as GAS isolated in culture from a sterile site,
e.g. blood and cerebrospinal fluid. We abstracted demographic
information, laboratory findings and microbiological data
including the site of isolation. We calculated overall and age-
specific rates of invasive and non-invasive GAS isolation, using
annual census population estimates for South Africa (reported
per 100 000 persons per year).
Results: From 2003 to 2013, 7 453 GAS isolates were recovered
from South African patients. Thirty-two per cent were from
patients under 18 years of age; 63% from those 18 to 64 years