CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 1, January/February 2013
250
AFRICA
Histological evidence of ischaemia was present in 4/4 after 4 hours.
Right ventricular ischaemia was visible on MRI after 6 hours of
ischaemic time in 1 animal. The right ventricular myocardium is thin-
ner than the left ventricular myocardium, making it difficult to distin-
guish myocardium from epicardium. Intraobserver variability for
MRI signal intensity of the myocardium was 0.93 (95% confidence
interval (CI) 0.91–0.94) for the LV and 0.18 (95% CI 0.03–0.37) for
the RV. The percentage difference in signal intensity between ischae-
mic and normal myocardium was greatest on T2-weighted images
up to 12 hours after death and then decreased with increasing time,
approaching that of the non-ischaemic areas by 24–48 hours.
Conclusions:
Ischaemic lesions of the LV, but not the RV, at least
4 hours old can be reliably detected as hyperintense areas on T2
weighted PMRI. By 24–48 hours after death, surrounding myocardial
density approaches that of the ischaemic area obscuring it.
1544: SPECTRUM AND OUTCOME OF PAEDIATRIC
PATIENTS UNDERGOING RIGHT VENTRICULAR PACING
Ameena Amod
1
, Annurupa Bhagwandin
1
, Andiswa Nzimela
2,3
,
Ebrahim GM Hoosen
2,3
1
Department of Cardiology, Inkosi Albert Luthuli Central Hospital,
Durban, South Africa
2
Paediatric Cardiology, Inkosi Albert Luthuli Central Hospital,
Durban, South Africa
3
University of KwaZulu-Natal, Durban, South Africa
Background:
Pacemaker implantation (PMI) in the paediatric popu-
lation is uncommon with implantation performed in selected patients
with congenital heart block or following cardiac surgery.
Aim:
To evaluate the spectrum and outcomes of patients undergoing
right ventricular (RV) pacing in the centre’s paediatric population.
Method:
A retrospective chart review of all paediatric patients
undergoing PMI since 2003 .
Results
: Seventeen patients were identified; 12 had congenital
complete heart block (CCHB), of whom 2 had associated struc-
tural abnormalities and 5 were heart block post cardiac surgery. Age
ranged from 7 days to 13 years. All implants were single-chamber
rate-responsive devices with 82% epicardially placed and 17.6%
endocardially. Epicardial placement was initially on the RV free wall
except for the last 3 which were placed on the RV outflow tract. Four
early mortalities in neonates with CCHB were recorded with one
late mortality. Associated morbidity in these patients included: 1)
hydrops fetalis in a patient with left isomerism and
total anomalous
pulmonary venous connection
(TAPVC); 2) long QT syndrome with
poor ventricular function post pacemaker implantation; and 3) Gram-
negative sepsis 9 days after PMI. Sudden unexpected death shortly
after PMI occurred in one neonate. Late mortality occurred from
pneumonia in a 14-month-old child with right isomerism/AVSD who
underwent PMI and pulmonary artery banding at 4 months of age.
Two patients with progressive heart failure at follow-up attributed to
pacemaker-induced cardiomyopathy were upgraded to biventricular
pacing with good results.
Conclusion:
While patient numbers were insufficient to reach any
clear conclusion, patients undergoing RV PMI had good outcomes,
the exception being those with heterotaxy syndrome and neonates
with comorbidity. Alternative pacing techniques to avoid or manage
pacemaker-induced cardiomyopathy may be indicated and requires
further investigation.
1545: QUANTITATIVE GATED SPECT VALUABLE TO
EFFECTIVENESS OF CARDIAC RESYNCHRONISATION
THERAPY IN FUNCTIONALLY SINGLE VENTRICLE
Tomomi Nishimura
1
, Im Sam Park
1
, Tomomi Ueda
1
, Tadahiro
Yoshikawa
1
, Naoki Wada
2
, Makoto Ando
2
, Yukihiro Takahashi
2
,
Kanki Inoue
3
1
Department of Pediatric Cardiology, Sakakibara Heart Institute,
Japan
2
Department of Pediatric Surgery, Sakakibara Heart Institute, Japan
3
Department of Cardiology, Sakakibara Heart Institute, Japan
Background:
Cardiac resynchronisation therapy (CRT) is effective
treatment for severe left heart failure. Recently, CRT has increasingly
been used in children and congenital heart disease (CHD) patients,
but published data about effectiveness are limited in comparison with
data on adults with left heart failure. Furthermore, for CHD patients
except cardiomyopathy, it is hard to evaluate the outcome.
Methods
: We describe a case of a 35-year-old woman with function-
ally single ventricle who started CRT 4 years ago because of fail-
ing Fontan. At baseline and after CRT, clinical status by New York
Heart Association (NYHA) class, ejection fraction (EF), ventricu-
lar dyssynchrony using quantitative gated single-photon emission
computed tomography (QGS) from Cedars-Sinai QGS software was
evaluated. Improvement of NYHA class and EF was considered
response. With 99mTc-sestamibi, end-diastolic volume (EDV), end-
systolic volume (ESV), ventricular EF, summed motion score (SMS),
and summed thickening score (STS) were calculated with QGS.
Results:
We could find improvement of EDV (210 ml to 186 ml),
ESV (173 ml to 120 ml), EF (18% to 35%), SMS (32 to 7), STS
(27 to 13) and uptake of nuclide to the myocardium. Phase analy-
sis derived from QGS polar map was indicated as heterogeneous
distribution in pre-CRT, and it was improved at follow-up. This case
showed improvement in NYHA class and EF.
Conclusions:
The radionuclide study is a useful examination to
evaluate synchrony because it is reproducible, simple and visual.
1562: SEVERE LEFT VENTRICULAR INFLOW OBSTRUC-
TION IN AN INFANT - AN UNUSUAL COMPLICATION
OF DILATED CORONARY SINUS: A CASE REPORT AND
REVIEW OF LITERATURE
Pankaj Gupta
1
, Christoph Camphausen
2
1
Department of Cardiology, Sydney Children’s Hospital Network,
NSW, Australia
2
Department of Cardiology, Sydney Children’s Hospital, NSW,
Australia
Introduction:
Dilated coronary sinus secondary to persistent left
superior vena cava is a common entity. However, dilated coronary
sinus causing severe left ventricular inflow obstruction is an infre-
quent finding. We report on a 4-month-old infant who presented
with congestive cardiac failure, secondary to marked enlargement of
coronary sinus with consequent obstruction of left ventricular inflow.
Case report:
A 4-month-old infant was referred to our paediatric
tertiary hospital with history of poor weight gain, breathlessness
during feeding and frequent sweating. Cardiovascular examination
revealed right parasternal heave with loud diastolic murmur at mitral
area. Electrocardiograph (ECG) showed right axis deviation with
marked right ventricular hypertrophy. Chest roentgenograms showed
mild cardiomegaly and passive pulmonary venous congestion. 2D
echocardiogram suggested diagnosis of cor triatriatum. However,
acquisition of stereoscopical 3D volume dataset identified the exact
nature of the obstruction and revealed persistent left superior vena
cava and markedly dilated coronary sinus causing severe narrowing
of inflow pathway of left ventricle. Operative finding confirmed the
diagnosis with presence of markedly dilated coronary sinus causing
narrowing of left ventricular inflow and absence of any membrane
in left atrium. He underwent reduction plasty of coronary sinus
which included longitudinal incision of coronary sinus, excision of a
segment of its wall and reconstruction of the dilated coronary sinus
wall. Excellent result was achieved with no residual left ventricular
inflow obstruction at follow-up.
Conclusion:
Dilated coronary sinus is a rare but possible aetiology
for left ventricular inflow obstruction. Reduction plasty of coronary
sinus is a safe and effective procedure for treating this entity. In
addition, stereoscopical 3D is an effective alternative to conventional
catheterisation for diagnosing this entity.
