CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 1, January/February 2013
190
AFRICA
806: EFFECT OF ANTI-HEART FAILURE THERAPY ON
VENTRICULAR END-DIASTOLIC PRESSURE IN CHIL-
DRENWITH SINGLE-VENTRICLE CIRCULATIONS
Deane Yim
1
, Peta Alexander
1
, Bryn Jones
1,2,3
, Yves D’Udekem
2,3,4
,
Michael Cheung
1,2,3
1
Department of Cardiology, Royal Children’s Hospital, Melbourne,
Australia
2
Department of Paediatrics, University of Melbourne, Australia
3
Murdoch Children’s Research Institute, Royal Children’s Hospital,
Melbourne, Australia
4
Department of Cardiac Surgery, Royal Children’s Hospital,
Melbourne, Australia
Background
: The systemic ventricle in children with single-ventri-
cle circulations is exposed to chronic volume loading. Heart failure
medications such as angiotensin converting enzyme inhibitors
(ACEI) and beta-blockers are frequently used despite a paucity of
evidence supporting their efficacy in this population. Our aim was to
determine the effect of ACEI
±
carvedilol on ventricular end-diastolic
pressure (EDP).
Methods:
Subjects with single-ventricle physiology who underwent
cardiac catheterisation between 1991 and 2011 were identified from
the departmental database. Subjects were included if they under-
went repeat catheterisation either pre- or post-Fontan and who were
commenced on ACEI
±
carvedilol, or had doses increased between
catheterisations. Those who underwent interventions influencing
loading conditions between catheter assessments were excluded.
Results
: Sixteen patients were identified.
Seven/16 (44%) had a
systemic right ventricle. There were 10 patients pre-Fontan and
six post-Fontan completion who had had repeated assessment. All
patients were treated with ACEI; two post-Fontan patients were
also commenced on carvedilol. The mean interval between assess-
ments was 14.8 months (range 2.5–41.6 months). ACEI
±
carvedilol
were instituted or increased over 11.9 months (3–33 months) before
haemodynamics were re-measured. Overall, a reduction in EDP from
a median of 13 mmHg (IQR 12–15.8 mmHg) to 10 mmHg (IQR
8.3–12.5 mmHg) was demonstrated (
p
=
0.001), as well as a fall in
mean atrial pressure from 11.5 mmHg (IQR 9.9–13.1 mmHg) to 9.2
mmHg (IQR 7–10.6 mmHg) (
p
=
0.01). A reduction in cardiothoracic
ratio (
p
=
0.04) was also observed.
Conclusions:
Ventricular diastolic function is an important deter-
minant of optimal flow in a Fontan circuit. Our data demonstrated a
significant reduction in EDP and mean atrial pressure in patients with
single-ventricle physiology following treatment with ACEI
±
carve-
dilol. Given that a raised ventricular filling pressure is a risk factor
for failure of Fontan palliation, these findings suggest the positive
haemodynamic effects of anti-heart failure therapy may impact on
clinical outcomes in this population.
810: WHAT IS NORMAL? ECHOCARDIOGRAPHIC FIND-
INGS IN LOW-RISK CHILDREN LIVING IN A REGION
WITH HIGH RATES OF RHEUMATIC HEART DISEASE
Kathryn Roberts
1
, Graeme Maguire
2,3
, Gavin Wheaton
4
, Marcus
Ilton
5
, Alex Brown
3,6
, David Atkinson
7
, Bo Remenyi
1
, Jonathan
Carapetis
1,8
1
Menzies School of Health Research, Darwin, Australia
2
James Cook University, Cairns, Australia
3
Baker IDI Heart and Diabetes Institute, Alice Springs, Australia
4
Department of Cardiology, Women’s and Children’s Hospital,
Adelaide, Australia
5
Department of Cardiology, Royal Darwin Hospital, Darwin, Australia
6
South Australian Health and Medical Research Institute, Adelaide,
Australia
7
University of Western Australia, Broome, Australia
8
Telethon Institute for Child Health Research, Perth, Australia
Background:
Echocardiographic screening for rheumatic heart
disease (RHD) is becoming more widespread, yet there are uncer-
tainties around the significance of mild valvular regurgitation or
morphological abnormalities, and few studies in low-risk children.
The aim of this study was to describe the echocardiographic findings
of healthy school-aged children in northern Australia, and to apply
the new 2012 World Heart Federation (WHF) criteria for the echocar-
diographic diagnosis of RHD.
Methods:
Portable echocardiography was performed on 1 087
predominantly Caucasian children aged five to 15 years in urban
Darwin and Cairns. Abbreviated echocardiograms were performed,
followed by comprehensive studies in those with pre-determined
indicators of possible abnormalities. Screening echocardiograms
were subsequently reported in a blinded standardised fashion by
cardiologists.
Results:
Of the 1 087 children screened, 106 (9.8%) had a compre-
hensive echocardiogram; 32 (2.9%) had at least one morphological
abnormality of the mitral valve (MV). A thickened anterior MV
leaflet (defined as
≥
3 mm) was most common (19 children); 214
children (19.5%) had some degree of mitral regurgitation (MR) with
the majority reported as trivial. Eleven children had MR jets
≥
2 cm
seen in at least one view
,
and only two children had MR which met
all four WHF criteria for significant MR. Aortic regurgitation (AR)
was found in 23 (2.1%). Five children had AR jets
≥
1 cm, three of
whom had bicuspid aortic valves. There were no cases of mitral or
aortic stenosis. Congenital abnormalities were detected in 16 chil-
dren (1.5%). No children met the WHF criteria for definite RHD, and
five children met the criteria for borderline RHD.
Conclusion:
Trivial MR is common in healthy school-aged children,
but significant regurgitation and morphological valvular abnor-
malities associated with RHD are rare. The absence of any cases of
definite RHD detected in this low-risk cohort suggests that the WHF
diagnostic criteria for RHD are appropriately specific.
815: PREVALENCE OF RHEUMATIC HEART DISEASE
IN HIGH-RISK CHILDREN IN NORTHERN AUSTRALIA:
APPLICATION OF THE 2012WORLD HEART FEDERATION
CRITERIA
Kathryn Roberts
1
, Graeme Maguire
2,3
, Alex Brown
2,4
, David
Atkinson
5
, Bo Remenyi
1
, Marcus Ilton
6
, Gavin Wheaton
7
, Andrew
Kelly
7
, Krishna Kumar
8
, Jonathan Carapetis
1,9
1
Menzies School of Health Research, Darwin, Australia
2
Baker IDI Heart and Diabetes Institute, Alice Springs, Australia
3
James Cook University, Cairns, Australia
4
South Australian Heath and Medical Research Institute, Adelaide,
Australia
5
University of Western Australia, Broome, Australia
6
Department of Cardiology, Royal Darwin Hospital, Darwin,Australia
7
Department of Cardiology, Womens and Childrens Hospital,
Adelaide, Australia
8
Department of Paediatric Cardiology, Amrita Institute of Medical
Sciences, Kochi, India
9
Telethon Institute for Child Health Research, Perth, Australia
Background:
Indigenous Australian children have among the high-
est prevalence rates of rheumatic heart disease in the world, as docu-
mented through local registers of clinical cases, but an epidemiologi-
cal survey has never been undertaken. This study aimed to establish
the prevalence of RHD in high-risk indigenous Australian children
using the new 2012 World Heart Federation diagnostic criteria.
Methods:
Portable echocardiography was performed on 4 158
predominantly Aboriginal and Torres Strait Islander children aged
five to 15 years living in remote communities of northern and central
Australia. Abbreviated echocardiograms were performed, followed
by comprehensive studies in those with pre-determined indicators
of possible abnormalities. Screening echocardiograms were reported
off-site in a blinded, standardised fashion by cardiologists.
Results:
Of the 4 158 children screened, 591 (14.2%) required a
comprehensive echocardiogram, the majority of which (80%) were
considered normal after secondary evaluation. Using the 2012 WHF
criteria, 30 children had definite RHD and 49 had borderline RHD.
Congenital abnormalities were detected in 57 children (1.3%).
