CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 1, January/February 2013
212
AFRICA
these complications is conventional invasive X-ray angiography.
Non-invasive retrospective triggered 64-MDCT has been shown to
be safe and accurate in some centres, albeit with a higher effective
radiation dose than conventional angiography (4.5 vs 3.1 mSv). Our
objective was to assess the feasibility of low-dose MDCT in detection
of coronary artery lesions with good image quality late after ASO for
repair of TGA.
Methods:
This was a prospective study of 14 patients operated on
for transposition of the great arteries with the arterial switch opera-
tion who underwent MDCT angiography. Ethical approval to carry
out this study was obtained from our institutional ethics commit-
tee, and all patients signed informed consent. Examinations were
performed using prospective ECG-triggered study at a dual-source
64-row MDCT. No beta-blockers were used for these patients. Two
independent investigators analysed MDCT angiography images for
quality and the ability to detect coronary artery stenosis, anatomy
and course. The effective dose was derived from the product of dose-
length product (DLP) and conversion coefficient for the chest based
on patient age using the Shrimpton and Wall method.
Results:
The median age was 15 years (IQR 13.8–16.4) with 78.6%
males and 21.6% females. Proximal coronary arteries were visualised
in all patients despite step artifact in 2/14. Left coronary artery origin
stenosis was identified in 2/14 patients. The mean dose-length prod-
uct (DLP) was 40
±
9.4 mGycm and mean effective radiation dose
was 0.55
±
0.13 mSv. The average heart rate was 74/minute.
Conclusion:
Prospective ECG-triggered MDCT angiography provid-
ed good quality and interpretable images with an added advantage of
lower radiation dose in coronary artery imaging in adolescents.
1113: MANAGEMENT OF HAEMOSTASIS IN PAEDIAT-
RIC PATIENTS AFTER PLACEMENT OF A VENTRICULAR
ASSIST DEVICE: REPORT FROM THE BERLIN EXCORÂ
PAEDIATRIC VENTRICULAR ASSIST DEVICE IDE STUDY
Patti Massicotte
1
, Marie Steiner
2
, Lisa Bomgaars
3
1
University of Alberta, Stollery Children’s Hospital, Canada
2
University of Minnesota, Minnesota, USA
3
Baylor College of Medicine, Houston, USA
Background:
Efficacious ventricular assist device (VAD) support in
paediatric patients depends on successful haemostasis management,
balancing the risk of thromboembolic complications with potential
life-threatening bleeding. The experience with the haemostasis
management algorithm developed for the EXCOR™ Paediatric IDE
study is described.
Methods:
All patients enrolled in the study were included.
Coagulation parameters and thromboembolic and haemorrhagic
events were reviewed for relatedness to antithrombotic therapy.
All events were centrally adjudicated. Evaluation of adherence to
the haemostasis management algorithm was based on mean results
of primary (PTT, INR, anti-factor Xa) and secondary (thrombo-
elastogram, platelet mapping) laboratory tests at pre-specified times.
Results:
One hundred and nine patients in primary study cohorts 1
and 2 (
n
=
48), continued-access patients (
n
=
20) and compassion-
ate-use cohort (
n
=
41) at IDE sites were included. Adherence to
antithrombotic guidelines was acceptable. Pump change occurred in
52% of all patients; half were hypercoagulable based on laboratory
or prior thrombotic history. Major bleeding occurred in 46% of all
patients. Mean haemostatic parameters in patients with major bleed-
ing trended to higher anti-factor Xa, PTT, and arachidonic acid plate-
let inhibition. Bleeding events were probably related to haemostasis
management in 18% of the total IDE group events. Neurological
events occurred in
<
30% of all patients; mean haemostatic param-
eters at the time of the event trended toward lower anti-factor Xa and
PTT on UFH, and higher net ADPG. Neurological dysfunction was
probably related in 9% and possibly in 42% of events to antithrom-
botic therapy intensity.
Conclusions:
Implementation of a haemostatic algorithm is crucial
to minimise VAD-related adverse events. Adherence to an algorithm
was possible in the setting of a multi-centre study. Incidence of
significant bleeding and thromboembolic events is acceptable when
balanced against potential life-saving benefits of the VAD. Additional
algorithm refinements and a standardised approach may further
improve safety and efficacy of haemostatic management.
1115: RELIABILITY OF ECHOCADIOGRAPHIC PARAM-
ETERS IN PREDICTING THE GRADE OF PULMONARY
REGURGITATION IN PATIENTS WITH TETRALOGY OF
FALLOT: ECHO COMPARED TO CMRI
Franziska Degener
1
, Nikolaus A Haas
1
, Kai Thorsten Laser
1
, Axel
Moysich
1
, Eugen Sandica
2
, Hermann Korperich
3
, Deniz Kececioglu
1
1
Department for Congenital Heart Disease, HDZ-NRW, Bad
Oeynhausen, Germany
2
Department for Surgery of Congenital Heart Disease, HDZ-NRW,
Bad Oeynhausen, Germany
3
Institute for Radiology, Nuclear Medicine, Molecular Imaging,
HDZ-NRW, Bad Oeynhausen, Germany
Introduction
: In tetralogy of Fallot the extent of pulmonary regur-
gitation (PR) and right ventricular (RV) volume load are the main
criteria for long-term assessment. Today the gold standard for evalu-
ation is cardiac magnetic resonance imaging (cMRI). Reliable echo-
cardiographic parameters for assessing PR are lacking.
Methods
: Analysis was carried out of 219 sequential cMRIs and
echocardiographic examinations in 118 patients over one year (53
female, 65 male, mean age 15.7
±
5.1 years, mean BSA 1.6
±
0.3
m²). Data were obtained within the German competence network for
congenital heart disease. cMRI: RV and left ventricular volumes and
ejection fractions were measured, PR was defined as mild (
≤
25%),
moderate (
>
25
≤
40%) and severe (
>
40%). Echocardiography: RV
diameters in M-mode, tricuspid valve annulus diameter, tricuspid
annular plane systolic excursion (TAPSE), tricuspid regurgitation,
right ventricular pressure (RVP), pressure half time (PHT), ratio of
the PR jet width to the pulmonary valve annulus (PR/PVA) and the
ratio of the regurgitation time divided by the diastolic time interval
(PRi) were assessed.
Results:
PR severity correlated with RV end-diastolic volumes (
p
<
0.001). TAPSE showed a significant difference between mild and
moderate (
p
=
0.033) as well as mild and severe PR (
p
=
0.004). PHT
showed similar results comparing the PR group of mild to severe
(
p
=
0.001) and moderate to severe (
p
=
0.018). Analogical results
were obtained by the PRi with
p
=
0.028 (mild/severe) and
p
=
0.022
(moderate/severe) and the PR/PVA ratio between mild and severe PR
(
p
=
0.049).
Conclusion
: With increasing severity of PR there was a decline in
RV function measurable by TAPSE. A short PHT and PRi indicated
a more rapid equilibration of RV and pulmonary artery pressure and
consequently a shorter PR time and PR/PVA ratio. TAPSE, PHT, PRi
and PR/PVA ratio are reliable and reproducible echocardiographic
tools to assess the severity of PR.
1117: ELECTROCARDIOGRAPHIC CHANGES AFTER
CARVEDILOL THERAPY OF CONGESTIVE HEART
FAILURE IN CHILDREN WITH LEFT-TO-RIGHT SHUNT
CONGENITAL HEART DISEASE
Teddy Ontoseno
Dr Soetomo Hospital, Surabaya, Indonesia
Background:
Heart failure (HF) is the most common complication
of left-to-right shunt congenital heart disease (L-R shunt CHD).
Sympathetic activity and stimulation of the renin–angiotensin–
aldosterone system are the compensation. Excessive and prolonged
compensations leads to heart remodelling. Medical treatment is
necessary for optimising the heart function. Carvedilol is a non-
selective beta-blocker, used as an additional drug in HF. The purpose
of this study was to determine the effects of carvedilol on changes
in heart rate, R-wave amplitude in V6, S wave amplitude in V1 and
R/S ratio in V1.
