CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 1, January/February 2013
AFRICA
277
100 000 but only 2% will develop symptoms within the first decade
of life. We present such a case in an infant.
History:
A four-week-old male infant developed poor feeding and
increasing breathlessness. He presented collapsed and in shock at six
weeks of age, requiring intubation and inotropic support. His worst
gas had a pH of 6.96 with a lactate of 16. Echocardiogram revealed
a poorly functioning hypertrophic dilated left ventricle with non-
compaction. After one week he was extubated.
Receiving regular anticoagulation, diuretics and beta-blocker
treatment, he remained clinically asymptomatic for the next 12
months other than having frequent respiratory infections. He grew
and developed normally despite dramatically poor echocardiographic
left ventricular function (rocking left ventricle with fractional short-
ening
<
10% and abnormal speckle tracking). He was negative for
Barth syndrome testing (a known association). At one year of age
he rapidly decompensated, requiring ventilation and inotropes. There
was no improvement and he was urgently listed for cardiac transplan-
tation. Unfortunately he died from an intracranial haemorrhage while
on a Berlin heart ventricular assist device awaiting transplantation.
This case was particularly challenging as the prognosis was so
uncertain, with poor outcome reported in 25% of children, while
others remain asymptomatic. This causes the family great difficulty
with coping. From the onset we were open in sharing the uncertain
future with the family, giving psychological as well as medical and
nursing support. This child was relatively well until the final dete-
rioration.
Conclusion:
Left ventricular non-compaction in childhood is rela-
tively rare and has a variable severity and an undulating course. This
case demonstrates the severe end of the spectrum.
1813: PARENTING/CAREGIVING WORK OF MOTHER-
AND-FATHER COUPLES WHO HAVE AN INFANT WITH A
COMPLEX CONGENITAL HEART DEFECT
Karen Pridham
1
, Tondi Harrison
2
, Mary Krolikowski
3
, Janet Melby
4
,
Kathleen Mussatto
5
1
University of Wisconsin, Madison School of Nursing
2
Nationwide Children’s Hospital, Columbus, Ohio, USA
3
Herma Heart Center, Medical College of Wisconsin, USA
4
Iowa State University, USA
5
Children’s Hospital of Wisconsin, USA
Background:
Parents of infants with a complex congenital heart
defect (CCHD) often describe caregiving demands and challenges.
Little is known about how parents manage with caregiving as a
couple through the infant’s first year. Although parents have identi-
fied the other parent as the most likely source of support, they have
also described providing this support as the most challenging aspect
of parenting.
Objective
: To learn what parents were working on together to parent
and give care to an infant with a CCHD through the first year of life,
how they were working on caregiving, and agreement or differences
in perspectives on the infant or about parenting/caregiving.
Methods:
Parents (mothers and/or fathers) of an infant with a
CCHD were interviewed in their homes at one, four or six, and 12
months after the infant’s birth. Parents responded to semi-structured
interview questions concerning parenting experience, including what
parents were working on, a question to learn about motivations, goals
and intentions concerning the infant, self, and the parent couple.
Results:
Among 21 caregiving parents, including three fathers,
approximately half were doing parenting work as a couple, 30% were
attempting to parent as a couple, and the remainder had no prospect
of couple parenting. Disagreement on the infant’s condition or what
the baby needed for care or parenting was higher when couples were
not parenting together, either cooperatively, collaboratively, or in
tandem.
Conclusions:
Differences in perspective on infant needs may put
couples at risk for parenting/caregiving difficulties. Motivations for
parenting/caregiving changed for some couples through the infant’s
first year. Two motivations likely to have continuity were to maintain
the couple’s relationship with the qualities it had before the infant’s
birth, and to keep attuned to each other, i.e. to ‘stay on the same
page’. Studies of support to couples’ accomplishment of parenting/
caregiving goals are needed.
831: THE IDENTIFICATIONANDVERIFICATION OF PUTA-
TIVE KCNE2-INTERACTING PROTEINS WITH RELE-
VANCE TO LONG-QT SYNDROME
Annika Neethling
1
, Jomien Mouton
1
, Carin de Villiers
1
, Ben Loos
2
,
Craig Kinnear
3
1
Department of Biomedical Sciences, Stellenbosch University, South
Africa
2
Department of Physiological Sciences, Stellenbosch University,
South Africa
3
Biology Section, Department of Biomedical Sciences, Stellenbosch
University, South Africa
Background:
Long-QT syndrome (LQTS) is a cardiac repolarisation
disorder characterised by a prolonged QT interval on an echocardio-
gram (ECG). The symptoms of LQTS range from minor symptoms
such as dizziness and syncope to more severe symptoms such as
seizures and sudden cardiac death (SCD). Clinical features of LQTS
are a result of the precipitations of torsades de pointes, which is a
form of polymorphic ventricular tachycardia. A number of genetic
forms of LQTS have been identified with more than 900 mutations in
10 different genes leading to disease pathogenesis. However a large
percentage of LQT-affected patients have no mutations within the
known LQT genes. Of these known mutated genes,
KCNE2
is one
that is associated with LQT6. This is a beta-subunit of potassium ion
channels of which the mutations are mainly located in the C-terminal
domain. We hypothesised that genes encoding for proteins that inter-
act with
KCNE2
might be identified as disease-modifying genes and
this study aimed to use a yeast two-hybrid (Y2H) analysis in order
to identify and verify putative interactors of the C-terminal domain
of
KCNE2.
Methods:
The C-terminal domain of
KCNE2
was used as bait to
screen a pre-transformed cardiac cDNA library using Y2H analysis.
Putative interactors will be verified using 3D-colocalisation and
co-immunoprecipitation experiments.
Results:
A number of putative
KCNE2
interactors were identified
by Y2H and are currently being verified. These include filamin C
(FLNC), protein tyrosine phosphatase (PTPRK), crystallin alpha
B (CRYAB), voltage-dependent anion-selective channel protein 1
(VDAC1), titin (TTN) and cardiac actin (ACTC1).
Conclusion:
The genes encoding verified interactors will be screened
in our South African panel of LQT patients, to potentially identify
novel LQT causative genes. Furthermore, the interactions verified in
this study may shed some light on the mechanism of pathogenesis of
LQT causative mutations in
KCNE2
.
