VOLUME 10 NUMBER 2 • JUNE 2013
77
SA JOURNAL OF DIABETES & VASCULAR DISEASE
CONFERENCE REPORT
PAH after 28 days. Melatonin was given in the drinking water (4 mg/
kg/day) for the 28-day period. Cardiac hypertrophy was confirmed
with a ratio of the right ventricle weight over heart weight (RVW/
HW). Cardiac functional parameters were assessed at 0 and 28
days using isolated heart perfusion and/or echocardiography. These
parameters included right ventricular systolic (SP) and diastolic pres-
sure (DP), ejection fraction (EF) and fractional shortening (FS).
Results:
MCT increased RVW/HW, reduced EF (92.84% ± 1.33 v.
60.53% ± 4.23,
p
<0.0003), FS (28.23% ± 2.68 v. 61.03% ± 2.89,
p
<0.0002) and increased SP and DP. Chronic administration of mela-
tonin in MCT-treated rats improved EF (60.5% ± 4.2 v. 84.1% ± 1.7,
p
<0.0008), FS (28.2% ± 2.7 v. 48.7% ± 2.1,
p
<0.0005), SP and DP.
Interpretation:
In conclusion our data demonstrate that chronic
melatonin improves cardiac function in MCT-induced PAH and sug-
gests a cardioprotective role of melatonin in PAH.
CATHETER-BASED RENAL SYMPATHETIC DENERVATION
FOR RESISTANT SYSTEMIC HYPERTENSION: A PILOT
STUDY
Nguchu H*, Gikonyo AK, Ravi Kumar R
Cardiology, Fortis Malar Hospital, Chennai, India
Introduction:
Resistant systemic hypertension is a major public
health problem in India and on the African continent. Since many
patients are unable to afford long-term drugs for hypertension, renal
sympathetic denervation could be a safe solution for this problem.
Subjects and methods:
We studied 10 Indian patients (4 male, 6
female) in the age group 35–58 years with resistant hypertension
on a minimum of 3 antihypertensive drugs, including diuretic (thi-
azide or torsemide) , angiotensin receptor blockers like telmisartan
or olmesartan , angiotensin-converting enzyme (ACE) inhibitors like
ramipril, beta-blockers (like metoprolol and nebivolol) and alpha-
blockers like prazosin and clonidine (in 2 cases). BP range (on three
drugs) was 190/106 to 156/98 (average of 170 systolic and 100
diastolic). Renal artery stenosis and azotaemia were ruled out. All
were taken for renal denervation procedure via femoral route in the
cardiac catheter laboratory. Mild sedation (injection of midazolam
1 mg) was given during the procedure. A 5F ablation catheter via a
6F femoral arterial sheath was used for the procedure along with a
Cordis radiofrequency ablator used to deliver 6-8 watts RF energy.
The ablation was performed in 3 opposite consecutive points in
each renal artery about 4 mm apart.
Results:
Post ablation patients had reduction in systolic and diasto-
lic blood pressures. After 1 week, BP range (on one or two antihy-
pertensive drugs) was 146/86 to 130/80; average 136/84. After 6
months the BP range on one to two drugs was 140/78 to 130/70.
Five patients who were followed up for 1 year had BP range of
140/80 to 130/76 on 1 or 0 antihypertensive drugs. No complica-
tions of the procedure were encountered.
Interpretation:
Catheter-based renal sympathetic denervation is a
useful procedure for systemic hypertension and may find extensive
applications in Africa.
AMBULATORY BLOOD PRESSURE MEASUREMENT
IN CAMEROON: HIGH PREVALENCE OF WHITE COAT
HYPERTENSION AND INFLUENCE OF BODY MASS INDEX
Noah T*, Dzudie A, Ndjebet J, Wawo EG, Kengne AP, Blackett Ngu K
Department of Internal Medicine, Faculty of Health Sciences, Uni-
versity of Buea, Buea, Cameroon
Introduction:
Identifying white coat hypertension (WCH) may avoid
inappropriate commitment of individuals to lifelong and costly blood
pressure (BP) lowering medications. We assessed the prevalence and
determinants of WCH in urban clinical settings in Cameroon.
Subjects and methods:
Participants were a consecutive sample of
adults, who underwent ambulatory BP measurements (ABPM) for
the diagnosis of hypertension and evaluation of treatment in three
referral cardiac clinics in the cities of Yaoundé and Douala, between
January 2006 and July 2011. WCH was defined as a clinic systolic
(or diastolic) BP ≥140 (90) mmHg together with an average daytime
ambulatory systolic (diastolic) BP <135 (85) mmHg.
Results:
Of the 500 participants included, 188 (37.6%) were
women, 230 (46%) were non-smokers and 53 (10.6%) had diabe-
tes mellitus. The mean age was 51.6 ± 10.2 years. The ABPM read-
ings were higher in men than in women (
p
<0.05). The prevalence
of WCH was 26.4% overall, 39.3% in women and 22.4% in men
(
p
=0.01). In multivariable analysis, body mass index (BMI) was the
only significant determinant of WCH (odds ratio 1.15 (95% confi-
dence interval: 1.00–1.43),
p
<0.05).
Interpretation:
The prevalence of WCH was high in our study
population and was correlated only with BMI. Accurate measure-
ment of BP and appropriate diagnosis of hypertension using ABPM
in this setting may help limiting the consequences of overestimating
hypertension severity on individuals, families and health systems.
THE SPECTRUM OF HEART DISEASE IN TWO CITIES IN
SUB-SAHARAN AFRICA UNDERGOING SOCIO-ECO-
NOMIC TRANSITION
Ojji D*, Stewart S, Ajayi S, Manmak M, Jacob A, Sliwa K
Cardiology Unit, Department of Medicine, University of Abuja
Teaching Hospital, Gwagwalada, Abuja, Nigeria
Introduction:
With rapid westernisation in sub-Saharan Africa,
cardiovascular disease is gradually becoming the major cause of
morbidity and mortality in this part of the world. Unfortunately,
there is still a dearth of data on the pattern of heart disease in
sub-Saharan Africa. We therefore studied the pattern of heart dis-
ease in Abuja, Nigeria and compared our findings with similar data
derived from the Heart of Soweto study.
Subjects and methods:
We prospectively studied 1 515 subjects
with confirmed cardiac disease referred to the cardiology clinic of
the University of Abuja Teaching Hospital during a 4-year period.
Equivalent data from the Heart of Soweto study in 4 626 subjects
were available for comparison.
Results:
The mean age of the study cohort was 49.0 ± 13.7 years.
Hypertension was the primary diagnosis in around two-thirds of the
study cohort. Hypertension was also the commonest cause of heart
failure (HF) accounting for HF in 60.6% of cases. The Abuja cohort
were more likely to present with a primary diagnosis of hyperten-
sion (adjusted odds ratio (OR) 2.10, 95% confidence interval (CI)
1.85–2.42), hypertensive heart disease/failure (OR 2.48, 95% CI
2.18–2.83;
p
<0.001 for both comparisons and representing more
than two-thirds of presentations in Abuja. Alternatively, they were
far less likely to present with coronary artery disease (CAD) (OR
0.04, 95% CI 0.02–0.11),
p
<0.001.
