Health - Personal cure saves family from heart condition

THEY were walking time bombs. Members of a family with an inherited
heart condition who knew at any time their hearts could stop pumping
enough blood through their bodies, causing stroke, heart failure or
death.
The condition, called dilated cardiomyopathy and usually incurable,
affects about one in 2000 Australians and leaves the heart weak and
enlarged.
But in a world first, Sydney researchers cracked the genetic codefor
one family suffering from the disorder, identifying a gene mutation
that would have eventually left some in need of a heart transplant, or
dead.
The Victor Chang Cardiac Research Institute led the project and
collaborated with St Vincent's Hospital to screen 42 members of the
family. Researchers found a rare mutation inthe cardiac sodium channel
among almost half of them.
Those affected were treated with a sodium channel blocker, a drug that
already existed. The drugs are not usually recommended for patients
with heart failure because of the potential side effects.
The institute's deputy director, Jamie Vandenberg, said it emphasised
the importance of personalised medicine, since the gene mutation that
caused the condition would not be the same in every family.
''The therapy we've devised is only appropriate for those with a
defect in this particular gene, which would be in the very small
percentages,'' he said.
''But about 40 per cent of people with dilated cardiomyopathy have a
genetic cause for the condition and new technology is making it easier
to identify those specific genetic causes. Depending on what
particular gene defect is identified, if we're lucky there will
already be a drug already available for it, as there was in this case,
and if not we will at least know which genes we need to target.''
Targeting genes would not be an effective treatment in those patients
for whom the cause was not genetic, he said. Infections, alcohol abuse
and exposure to toxins were also thought to be responsible.
The study was published in the Journal of the American College of
Cardiology and its lead author, Diane Fatkin, said even those patients
with severe disease had returned to full health within six months.
''This is game-changing research,'' she said. ''Whilst we can only
claim to have treated one particular mutation that causes cardiac
dysfunction, and there isstill much more to do to find the genetic
causes of heart disease in every family, this is a huge step in the
right direction.''
Dilated cardiomyopathy can affect people of all ages, from newborns to
the elderly.