CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 3, April 2013
AFRICA
81
Consecutive patients with a diagnosis of RHD were enrolled
in this cross-sectional study between June 2010 and January
2012. We report on complication rates at presentation in those
who were newly diagnosed with definite RHD.
The study was conducted at Mulago Hospital, Uganda’s main
national referral hospital and teaching hospital for the Makerere
University College of Health Sciences. Annually, Mulago
Hospital admits approximately 60 000 patients and diagnoses
approximately 240 new cases of rheumatic heart disease.
For the purposes of this study, we were exclusively interested
in patients newly diagnosed with RHD. To be included in this
analysis, the patient was required to be between the ages of 15
and 60 years, to have definite RHD (2006 WHO/NIH criteria)
confirmed by echocardiography, and to be willing to sign
informed consent.
Exclusion criteria included prior diagnosis of RHD, age
<
15 or
>
60 years, and/or presence of congenital heart disease.
Furthermore, patients found to have atrial fibrillation in addition
to abnormal electrolyte levels or abnormal thyroid function tests
were also excluded. Medical doctors from the Mulago Hospital
complex as well as other regional hospitals were invited to
participate in the study by referring all patients aged 15 to 60
years with suspected RHD to the study site.
Patients who were referred for evaluation underwent a
comprehensive screening evaluation to determine the presence
or absence of rheumatic heart disease. A medical history was
obtained, including history of acute rheumatic fever (ARF): recent
sore throat, joint pain, tremors or skin rash. A comprehensive
physical examination including auscultation of the chest was
carried out. A specific search for known complications of RHD
such as heart failure, pulmonary hypertension, atrial fibrillation,
infective endocarditis, stroke and recurrence of acute rheumatic
fever was carried out during the physical examination and was
later confirmed by specific tests.
Standard transthoracic echocardiography (GE, Vivid 8,
Chicago, USA) was preformed according to theAmerican Society
of Cardiology guidelines.
11
Patients found to have congenital
heart disease were referred to the Paediatric Cardiology Division
for further evaluation. For the remainder of the patients, the 2006
WHO/NIH Joint Consensus Statement on Echocardiographic
Diagnosis of RHD was used to classify patients as ‘definite’,
‘probable’, or ‘possible’ RHD, or as ‘no disease’.
12
Cases confirmed to have definite RHD were asked to
sign informed consent. Study participants then completed
a detailed demographic profile and clinical questionnaire.
They also underwent a chest X-ray and standard 12-lead
electrocardiography (Cardiopac, Germany). Finally, 6 ml of
venous blood was obtained through peripheral venipuncture,
and complete blood counts, anti-streptolysin O (ASO) titres,
erythrocyte sedimentation rate and C-reactive protein were
determined.
Echocardiographic definitions
Echocardiographic images were obtained from the parasternal
long-axis, parasternal short-axis, apical four- and five-chamber
and sub-costal views. Morphological abnormalities of the mitral
valve, including thickening or calcification of the leaflets, and
fusion, shortening, fibrosis, and /or calcification of the mitral
chordae were recorded.
Mitral stenosis was labelled as significant if there was
evidence of flow acceleration across the mitral valve with a
mean pressure gradient
>
4 m/s.
12
Severity of mitral stenosis
was determined by planimetry and pressure half-time methods,
as mild (MVA
>
1.5 cm
2
), moderate (MVA
=
1.1–1.5 cm
2
) and
severe (MVA
<
1.0 cm
2
). Mitral regurgitation was labelled as
significant if it was seen in two views by colour Doppler, was
>
2 cm from the coaptation point of the valve leaflets, was high
velocity, and persisted throughout systole.
12
Mitral regurgitation
was classified as severe if there was systolic flow reversal in the
pulmonary veins.
Morphological abnormalities of the aortic valve, including
commissural fusion of the aortic leaflets, increased echogenicity
along the leaflet edges, and systolic doming of the aortic leaflets
was noted. Aortic stenosis was graded based on valve area as
well as using flow velocity and mean pressure gradient across the
valve (mild if valve area
>
1.5 cm, moderate if valve area was
1.1–1.5 cm and severe if valve area
<
1 cm). Aortic regurgitation
was labelled as significant if it was seen in two planes, was at
least 1 cm from the coaptation point of the valve leaflets, and
was high velocity.
12
Complications of rheumatic heart disease
Following a pre-study survey of common complications
presenting on our wards, a consensus was made to profile the
following complications as they occurred:
•
Heart failure, which was defined according to the Framingham
criteria,
13
and NewYork Heart Association functional status.
•
Acute rheumatic fever was defined according to the 1992
14
and 2003 WHO modified Jones criteria for diagnosis of ARF
recurrence in patients with RHD.
15
•
Infective endocarditis was diagnosed according to standard
criteria as previously published.
16
•
Atrial fibrillation was diagnosed using the blinded Minnesota
code.
17
•
Stroke was diagnosed during history and clinical examination,
and confirmed on brain computer tomography scan (CT scan).
•
Pulmonary hypertension (PAH) was diagnosed based on
clinical examination (findings of a loud second heart sound,
murmur of tricuspid regurgitation, dilated pulmonary arteries
on a chest X-ray) and confirmed using echocardiography.
Doppler interrogation of tricuspid valve regurgitation was
used to quantify the pulmonary arterial pressure. Pulmonary
arterial systolic pressure (PASP) over 36 mmHg was defined
as pulmonary hypertension.
18
Statistical analysis
Data were double entered and stored in EPI data version 3.0
(EpiData Association, Odense M, Denmark). Analysis was done
using STATA 10.0 statistical package (Stata Corporation,College
Station, TX, USA). Categorical variables were analysed using the
Chi-square test, while continuous variables were analysed using
the independent-samples two-tailed Student’s
t
-tests. Results are
expressed as means
±
standard deviation. In all statistical tests,
p
<
0.05 was regarded as significant.
Results
Three-hundred and eighty patients with suspected RHD were
referred for study enrollment. Congenital heart disease was
