CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 1, January/February 2013
AFRICA
239
growth potential, and may have implications for understanding the
relative benefits of different approaches to the Fontan procedure.
1412: DISTRIBUTION OF HEART DISEASE IN A MULTI-
CENTRE PAEDIATRIC CARDIAC REGISTRY
Pouya Hemmati
1
, James St. Louis
2
, Lazaros Kochilas
2
, Lee Pyles
2
1
University of Minnesota Medical School, Minneapolis, MN, USA
2
University of Minnesota Amplatz Children’s Hospital, Minneapolis,
MN, USA
Background:
The incidence of congenital heart disease is generally
eight per 1 000 live births. The University of Minnesota’s multi-
centre Paediatric Cardiac Care Consortium (PCCC) has enrolled
children undergoing cardiac catheterisation, operation or autopsy
examination since 1982. The study comprises all registered children
born from 1991–2002 to state residents of Arkansas (AR), Minnesota
(MN) and Missouri (MO). We hypothesised that age-stratified inci-
dence of heart disease could be established for these states to investi-
gate paediatric cardiac case finding and management.
Methods:
De-identified PCCC records for children born from
1991–2002 in AR, MN and MO were analysed and categorised by
diagnosis to calculate birth rate-adjusted incidence. Conditions with
abnormal oximetric saturation that were detected by three months of
age are ‘oximeter-screenable’ anomalies.
Results:
The rate of registered heart disease for subjects born from
1991–2002 for the three states was 46.3 per 10 000 live births (1.8
million births). For PCCC registrations within the first three months
of life, 17.1/10 000 were oximeter-screenable and 13.7/10 000 were
potentially cyanotic (e.g. PS, CAVC), compared with the total inci-
dence of 37.0/10 000. MO showed significantly higher registration
rates for CAVC (Poisson distribution,
p
=
0.012), coarctation (
p
=
0.0015), TOF (
p
=
0.028) and VSD (
p
=
0.0029). AR registered more
than half of left-to-right shunts within the first three months [9.4/10
000 for
<
3 months vs 18.5/10 000 all ages (Poisson distribution,
p
=
0.00064)].
Conclusions:
PCCC-registered overall heart disease rates showed no
significant differences among states. Although other anomalies often
present with desaturation, only 46% of heart disease registered within
three months of life is oximeter-screenable. Therefore, additional
screening methods are needed to optimally manage paediatric heart
disease. Incidence and timing of presentation of specific anomalies
and categories from a large cohort were analysed to allow insights into
detection and management of paediatric heart disease and can be used
to investigate mechanisms of environmental and genetic causation.
1415: DIASTOLIC FILLING IMPAIRMENT DURING EXER-
CISE LIMITS EXERCISE CAPACITY IN FONTAN PATIENTS
Alexander Van De Bruaene
1
, Andre La Gerche
1,2
, Guido Claessen
1
,
Pieter De Meester
1
, Sarah Devroe
3
, Jan Bogaert
4
, Piet Claus
5
, Hein
Heidbüchel
1
, Werner Budts
1
, Marc Gewillig
6
1
Department of Cardiovascular Medicine, University Hospitals
Leuven, Belgium
2
Department of Medicine, University of Melbourne, St Vincent’s
Hospital, Australia
3
Department of Anesthesiology, University Hospitals Leuven,
Belgium
4
Radiology Department, MIRC, University Hospitals Leuven,
Belgium
5
Laboratory of Cardiovascular Imaging and Dynamics, University of
Leuven, Belgium
6
Paediatric Cardiology, University Hospital Leuven, Belgium
Background:
Better imaging techniques are needed to assess
haemodynamic changes that limit exercise performance in Fontan
patients. This study aimed at evaluating changes in end-diastolic and
end-systolic volumes (EDV and ESV) using a novel cardiac magnetic
resonance (CMR) methodology during mild, moderate and strenuous
exercise.
Methods:
Seven Fontan patients (five male, age 19
±
5 years) under-
went CMR at rest and during supine exercise on a programmable
cycle ergometer. Systemic ventricular volumes were obtained at rest
(heart rate 77
±
13 bpm) and during mild (105
±
10 bpm), moderate
(129
±
15 bpm) and strenuous (144
±
13 bpm) exercise. Images were
acquired using an ungated, free-breathing real-time CMR sequence
(12–18 contiguous 8-mm slices). Software was developed to allow
for synchronisation of short- and long-axis images with compen-
sation for respiratory phase translation. Endocardial borders were
delineated using a bi-plane model. Simultaneously, pulmonary artery
pressures were measured during exercise using a fluid-filled catheter.
Results:
Cardiac output (CO) increased continuously during exercise
(6.6
±
1.9 vs 9.4
±
1.8 vs 11.1
±
3.5 vs 11.5
±
3.4 l/min;
p
<
0.0001).
The increase in CO depended on a 94
±
40% increase in heart rate.
Stroke volume (SV) did not change from rest to mild exercise (87
±
22 vs 90
±
20 ml;
p
=
0.458) and decreased during moderate and
strenuous exercise (90
±
20 vs 85
±
22 vs 79
±
17 ml;
p
<
0.0001).
EDV increased from rest to mild exercise (162
±
39 vs 170
±
43 ml;
p
=
0.040), but decreased during moderate and strenuous exercise
(170
±
43 vs 164
±
47 vs 158
±
45 ml;
p
=
0.004) whereas ESV did
not change during exercise (74
±
28 vs 80
±
32 vs 78
±
35 vs 80
±
38 ml;
p
=
NS). Mean pulmonary artery pressures increased during
exercise (10
±
4 vs 14
±
4 vs 18
±
4 vs 22
±
5 mmHg;
p
<
0.0001).
Conclusions:
In Fontan patients, CO augmentation during exercise
was predominantly dependent upon increasing heart rate. Impaired
ventricular filling caused a decrease in SV already evident at moder-
ate exercise, suggesting that decreased preload reserve is an impor-
tant determinant limiting exercise capacity.
1417: POPULATION STUDY OF 332 CONSECUTIVE
NEWBORNS WITH HYPOPLASTIC LEFT HEART
SYNDROME (HLHS): A SINGLE-CENTRE EXPERIENCE
Anna Mazurek-Kula, Jadwiga A Moll, Jacek J Moll, Andrzej Sysa
1
Polish Mother’s Memorial Hospital, Poland
Background:
Our hospital is one of the leading centres for HLHS
treatment in Poland.
Aim:
The aim of the study was the estimation of perinatal and
anatomic data of consecutive newborns with HLHS operated at our
institution.
Methods:
This was a retrospective analysis of perinatal data and
anatomical findings of 332 newborns with HLHS (226 boys: 68%
and 106 girls: 32%) treated by staged Norwood operation at our
institution from 1992 to 2011.
Results:
Prenatal diagnosis was made in 58% of patients (68–75%
in last five years), mean pregnancy duration was 39.4
±
1.8 (31–43)
weeks. Mean mother’s age was 26
±
5 (17–43) years. In 147 cases
(44%) the child with HLHS came from the first pregnancy. Mean
Apgar score was 8.7
±
1.4 (1–10), mean birth mass was 3236
±
505.6
g (1 995–4 430 g). Ten patients (3%) came from twin pregnancies.
Five patients (1.5%) had coexistent extracardiac malformations.
In four cases (1.2%) our patient was the second child with HLHS
from the same parents. In six families (1.8%) cardiac or extracardiac
malformations in the HLHS patient’s siblings were confirmed (in
two families TGA in a sibling). In one patient Turner syndrome (45,
X) was diagnosed. Anatomical subtypes of HLHS: MA/AA in 123
patients (37%); MS/AA in 113 patients (34%); MS/AS in 93 patients
(28%); MA/AS in three patients (1%). Right ventricle myocardial
performance index (RV-MPI) was 0.521
±
0.18 (0.2–0.968) vs 0.3
±
0.078 (0.183–0.445) in the control group of 50 healthy newborns.
Restrictive atrial communication was confirmed in 33 patients
(10%). Mean ascending aorta diameter was 3.8 mm (1–7.5 mm).
Severe tricuspid regurgitation was diagnosed in 40 patients (12%).
Conclusions:
Patients with HLHS were usually male, well devel-
oped, full-term delivery newborns of a young mother. HLHS rarely
coexisted with other malformations or genetic disorders. In our
material MA/AA, MS/AA, MS/AS subtypes occurred with similar
frequency, MA/AS was very rare. RV-MPI for HLHS patients was
significantly higher compared with healthy neonates.
