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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 5, September/October 2017
AFRICA
281
HF was diagnosed as per the ACCF/AHA and ESC guideline
definition.
15,16
The assessment of HF was made based on a
combination of the patient’s history, clinical signs as well as
available clinical records. A total of 66 patients with presumed
CRMR underwent clinical evaluation, resting electrocardiogram
and detailed echocardiographic assessment according to a
predetermined protocol.
The inclusion criteria were as follows: patients aged 18 years
or older with echocardiographic features of severe CRMR;
symptomatic (NYHA II–III); left ventricular ejection fraction
≤
60%; refusing or awaiting surgery; and on medical therapy [ACE
inhibitors, angiotensin receptor blockers (ARBs), beta-blockers
or aldosterone receptor antagonist] for HF.
Patients were excluded if they had significant aortic valve
disease, concurrent mitral stenosis (MS) with a valve area of less
than 2.0 cm
2
, documented ischaemic heart disease, pre-existing
non-valvular cardiomyopathy, prior cardiac surgery, congenital
or pericardial disease, pregnancy, severe systemic disorders
such as renal failure, uncontrolled hypertension (systolic blood
pressure
>
140 mmHg and diastolic blood pressure
>
90 mmHg)
on medication, or severe anaemia (haemoglobin
<
10 g/dl).
Thirty-five patients were excluded due to the following:
anaemia, renal dysfunction, mild or moderate MR, MR of
non-rheumatic aetiology and inadequate image quality. The
final sample included 31 patients. Most HF trials conducted
with anti-remodelling agents required a minimum duration of
three months to demonstrate benefit.
17
We therefore followed up
patients in this study for a period of six months.
All the patients included in the sub-study were receiving some
form of medical therapy for HF. All were on the minimum dose
of their respective HF medications and were up titrated at three
months where indicated, based on symptoms, blood pressure,
and urea and creatinine levels.
All patients enrolled in this study were on a combination of at
least one anti-remodelling agent inaddition toadiuretic for at least
oneweek. Therapy comprisedbeta-blockers (atenolol, carvedilol),
ACE inhibitors/ARBs (enalapril, perindopril, telmisartan) and
an aldosterone receptor antagonist (spironolactone), in addition
to digitalis and diuretics. Medication was initiated at the
discretion of the treating physician. All medications were either
down titrated or withdrawn, or substituted on follow-up visits if
side effects were reported.
Patients were followed up at one, three and six months. At one
and six months, a full clinical assessment was done, including the
Minnesota HF questionnaire and six-minute walk test. The dose
of the medication was titrated at one month and full titration
was achieved at three months by the treating physician.
Transthoracic echocardiography was performed on all
patients in the left lateral position by experienced sonographers
using a S5-1 transducer on a Philips iE33 system (Amsterdam,
the Netherlands). The images were obtained according to a
standardised protocol at baseline and at the six-month follow
up. The data were transferred and analysed offline using the
Xcelera workstation (Philips). Echocardiographic measurements
were done by the researcher at baseline and the follow-up
measurements were done by an experienced sonographer who
was blinded to the initial results.
For two-dimensional and Doppler quantification, all
linear and volumetric chamber measurements were performed
according to the American Society of Echocardiography (ASE)
chamber guidelines at baseline and at six months.
18
Measurements
relating to LV diastolic function were performed in accordance
with the ASE guidelines on diastolic function and included
pulse-wave Doppler at the mitral tips and tissue Doppler of both
medial and lateral mitral annuli at baseline and at six months.
19
Measurements relating to the right ventricle were based on the
ASE guidelines on the right ventricle.
20
MR was considered rheumatic in aetiology when the
morphology of the valve satisfied the World Heart Federation
(WHF) criteria for the diagnosis of chronic rheumatic heart
disease.
21
MR severity was assessed using qualitative, semi-
quantitative and quantitative methods (integrated approach)
as per the ASE valvular regurgitation guideline.
22,23
In equivocal
cases, the echocardiographic data were integrated with the
clinical evaluation by an experienced cardiologist to distinguish
moderate from severe MR.
For speckle tracking echocardiography, left atrial peak
systolic strain and left and right ventricular peak systolic strain
were measured as previously described.
24-30
Statistical analysis
Statistical analysis was performed with Statistica (version 12.5,
series 0414 for Windows). Continuous variables are expressed
as mean
±
SD or median (IQR). Paired Student’s
t
-test or
Wilcoxon’s matched-pairs test were used to compare continuous
variables. Categorical variables are expressed as percentages. A
p
-value of
<
0.05 was recognised as statistically significant.
Results
The baseline clinical characteristics are summarised in Table 1.
There was no change in systolic and diastolic blood pressure
or heart rate from baseline to six months [125
±
12.6 vs 120.1
±
10.2 mmHg,
p
=
0.09; 76.2
±
12.2 vs 74.2
±
11.02 mmHg,
p
=
0.5;
71.5 (70–81) vs 71.0 (61–80) beats/min,
p
=
0.43, respectively].
The median Minnesota HF score at the start and the end
of treatment at six months was 34 (18–61) and 32.5 (13–48),
respectively (
p
=
0.3). There was no difference in the six-minute
walk test at the onset of treatment and at six months (265.5
±
103.0 vs 275.4
±
71 m,
p
=
0.6).
None of the patients were hospitalised for HF and all were
alive at six months. Baseline and maximum therapeutic doses of
Table 1. Baseline clinical characteristics
Variable
Number
=
31
Age (years)
50.7
±
8.5
Gender (female/male)
29/2
Systolic blood pressure (mmHg)
125
±
12.6
Diastolic blood pressure (mmHg)
76.2
±
12.2
Heart rate (beats/min)
71.5 (70–81)
Body surface area (m
2
)
1.73
±
0.16
Body mass index (kg/m
2
)
28.1
±
6.1
NYHA class II–III (%)
31 (100)
Hypertension (%)
29 (93)
HIV (%)
7 (23)
Atrial fibrillation (%)
2 (6.4)
Data are presented as median (interquartile range), mean
±
SD or %.
HIV, human immunodeficiency virus; NYHA, New York Heart Association
functional class.