CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 1, January/February 2013
198
AFRICA
GmbH; Germany). C-u/s was performed using an 18-MHz linear
transducer (Esaote, Italy) at bilateral transverse sections of three
designated segments. The digital images were blinded, the propor-
tional area of the B-lines in each section was graded from one (0%) to
five (
>
75%), and a mean chest sonographic score (C-SS) of the six
measurement points was used for the statistics. Statistical differences
were studied using the Mann-Whitney
U
-test.
Results:
TGA patients had significantly more B-lines on C-u/s post-
operatively (
p
=
0.01) and on first postoperative day (
p
=
0.01) than
patients with shunt defects. L-Cst did not differ significantly between
patient groups.
Conclusions:
Measurement of LE by ultrasound is a quick, easy
and safe procedure, which may prove to be useful in postoperative
evaluation of patients with CHD. Complex open-heart surgery or
significant hypoxaemia, or both, may increase and prolong postop-
erative LWC.
890: INSIGHT INTO DYNAMIC THREE-DIMENSIONAL
MITRAL VALVE GEOMETRY AND ANNULAR FUNCTION
IN NORMAL CHILDREN, ADOLESCENTS AND YOUNG
ADULTS: A NOVEL METHODOLOGY
Akio Inage
1,3
, Ken Takahashi
1,4
, Richard Thompson
2
, Jeffrey
Smallhorn
1
1
Division of Paediatric Cardiology, University of Alberta, AB,
Canada
2
Department of Biomedical Engineering, University of Alberta, AB,
Canada
3
Division of Paediatric Cardiology, Sakakibara Heart Institute, Tokyo,
Japan
4
Department of Paediatrics, Juntendo University Faculty of Medicine,
Tokyo, Japan
Background:
We have previously reported dynamic mitral annular
function in children. However this relationship to the leaflets and
papillary muscles was not possible with earlier software.
Aim:
To demonstrate dynamic relationships between the leaflets, the
papillary muscles (PMs), and the mitral annular function throughout
the cardiac cycle in a young population.
Methods:
Forty healthy volunteers, with the mean age of 15.7
(3.4–38.4) years, underwent apical left ventricular full-volume imag-
ing with real-time three-dimensional echocardiography (RT3DE) at a
frame rate of 30–40 FPS. RT3DE data set was cropped into 15 slices
(spaced 24 degrees) around the centre of the mitral valve. Data analy-
sis was performed using prototype software (TomTec Inc). Leaflets
and PMs were manually traced at each slice during mid-systole (MS),
late-systole (LS) and late-diastole (LD), and were reconstructed
as a 3D graph using our customised software (MathWorks Inc).
Measurements included annular area, bending angle and height,
and tethered and prolapsed volume of the leaflets, and anterolateral
(APM)/posteromedial PM (PPM) angle.
Results:
There was a strong correlation between the annular bending
angle and the height throughout all phases of the cardiac cycle (range
of
p
values 0.007 to
<
0.001). There was a correlation between the
annular area and the height during MS and LS (
p
=
0.001 and 0.004).
On the other hand, there was no correlation between the PM angle
and the bending angle at MS and LD, but a weak correlation between
them at LS (
p
=
0.04). Both ‘normal’ tethered and prolapsed volume
of the leaflets had a correlation with the APM angle (
p
=
0.01), but
not with the PPM angle.
Conclusion:
Dynamic mitral annular functions could be assessed
quantitatively. In particular, the angle between the PMs and the mitral
annulus was constant throughout the cardiac cycle.
894: RESOLUTIONAND COMPLICATIONS OF CORONARY
ARTERY ANEURYSMS AFTER KAWASAKI DISEASE
Brian W McCrindle, Elizabeth Niedra, Leonardo R Brandao, Nita
Chahal, Cedric Manlhiot
Hospital for Sick Children, University of Toronto, Toronto, Canada
Background:
Coronary artery aneurysms (CAA) that fail to resolve
by returning to a normal luminal dimension after Kawasaki disease
(KD) are at high risk for both thrombotic and stenotic complications.
Methods:
We reviewed
the case records of 169 patients with KD and
CAA (1999
–
2012). CAA were classified as small (
z
>
2.5
–
5.0), large
(
z
>
5.0
–
10.0) or giant (
z
>
10.0) using previously published criteria.
Time to resolution (
z
<
2.5) and freedom from thrombosis or stenosis
were determined.
Results:
For small CAA (
n
=
102), at one/five years after acute
KD, the proportion of CAA showing resolution were: 57
–
78% and
90
–
100% depending on the coronary branch. For giant CAA (
n
=
51),
the proportion of CAA showing resolution at one, five and 10 years
were 0
–
7%, 15
–
34%, and 40
–
73%, respectively. Patients with small/
large CAA were not at risk for either thrombosis/stenosis. Patients
with giant CAA were at substantial risk (20% at two months, 33% at
five years and 47% at 10 years) despite 82% on anticoagulation; 43%
of thromboses had important consequences (seven thrombolytics,
three myocardial infarctions, one death). Freedom from stenoses was
96/77% at one/five years. Factors associated with CAA resolution
included smaller maximum CAA
z
-score (HR: 0.928/
z
,
p
=
0.02),
smaller CAA longitudinal area (length
×
diameter
×
0.8) (HR: 0.850/
cm
2
,
p
=
0.03) and younger age at diagnosis (HR: 0.847,
p
=
0.02).
Low albumin level, high erythrocyte sedimentation rate, C-reactive
protein and neutrophil levels at three months and one year after acute
KD were associated with CAA persistence. Factors associated with
increased risk of thrombosis were higher maximum CAA
z
-score
(HR: 1.072/
z
,
p
<
0.001) and higher CAA longitudinal area (HR:
1.050/cm
2
,
p
=
0.02). Factors associated with increased risk of sten-
oses were higher maximum CAA
z
-score (HR: 1.071/
z
,
p
=
0.003),
smaller CAA longitudinal area (HR: 1.037/cm
2
,
p
=
0.05) and the
presence of complex (vs isolated) CAA) (HR: 9.0,
p
=
0.04).
Conclusions:
Resolution of CAA is prevalent and is influenced by
the location, maximum size and extent of involvement, and is more
likely in younger patients. Despite aggressive thromboprophylaxis
strategy, patients with giant CAA continue to be at substantial risk of
thrombotic and stenotic complications.
900: PROTHROMBOTIC GENE POLYMORPHISMS IN
PATIENTS WITH CONGENITAL HEART DISEASE WITH
ANDWITHOUT TRISOMY 21
Lia Stenyk, Cedric Manlhiot, Seema Mital, Leonardo R Brandao,
Ashok K Manickaraj, Brian W McCrindle
Hospital for Sick Children, University of Toronto, Toronto, Canada
Background:
Children with congenital heart disease represent the
paediatric patient population at the highest risk of thrombosis, mainly
due to exposure to multiple pro-thrombotic factors. Limited evidence
regarding a genetic predisposition to thrombosis in these patients is
available. We sought to determine whether patients with congenital
heart disease have an increased prothrombotic polymorphism burden
and whether the subpopulation with trisomy 21 has magnified risk.
Methods:
A total of 381 patients with congenital heart disease were
reviewed. Ninety-six SNPs on 53 genes involved in the coagula-
tion/fibrinolysis pathways were assayed using the the Illumina
GoldenGate
®
custom SNP panel; genotyping was successful for
>
99% of SNPs. Minor allele frequency was compared to population
average; a difference of 14% was considered statistically significant
(corresponding to a
p
-value
<
0.005 adjusted for multiple testing).
Differences between patients with trisomy 21 and those with no
known genetic abnormalities were compared with bootstrap resam-
pling (1 000 samples,
>
50% reliability) for SNP selection.
Results:
Population-based minor allele frequency was available for
91 SNPs; 11 (12%) SNPs had minor allele frequency differences
from population-based averages. These included seven SNPs known
to be associated with increased venous thrombosis risk, including one
known to affect fibrinogen levels and three associated with coagula-
tion factor activity. Trisomy 21 was present in 27 (7%) patients, 17
(4%) had other genetic syndromes. Patients with trisomy 21 had
increased frequency of TT polymorphism in coagulation factor
