Heartfelt thanks as test for gene cheats death

Adele Clayton, son Tom (15) and daughter Marin (9) all have the potentially deadly Long QT syndrome. Picture / Glenn Jeffrey

It took a near-fatal heart attack for Adele Clayton to discover she had a defective gene that could cause sudden death - and she had passed it on to all four of her children.

"Unfortunately that seems to be the most usual way you get diagnosed, if you're lucky enough to survive."

But Long QT syndrome, which can cause sudden cardiac arrhythmia (rapid, chaotic heart rhythms), and is a significant cause of sudden deaths in young people, can now be diagnosed with a simple blood test, thanks to Auckland University researchers.

Medical staff can now test patients who have had sudden cardiac episodes, and their families, to identify those with a defective Long QT gene.

Most people with the defect can be treated by implanting a defibrillator pacemaker or by medication.

Ms Clayton, a nurse, was one of the first diagnosed with the new test. But it was the heart attack in May 2002 that led Auckland researchers to her.

She was asleep in bed when her husband Mike woke to hear her gurgling - "the end stage".

"He found I didn't have a pulse, and I'd stopped breathing completely by then. My eyes were what you'd call fixed and staring."

Her husband began resuscitation. "He'd seen on ER a resuscitation and they'd made a comment about the bed being too soft ... He tried to pick me up to put me on the floor, but dropped me - luckily."

The impact jump-started her heart.

"Dropping me saved me."

At the hospital, Long QT syndrome was suspected after testing ruled out other possible conditions.

But it was only when results from the researchers' test came back almost a year later that the disorder was confirmed. Tests also confirmed the defective gene in Ms Clayton's four children, Danielle, 26, Jake, 17, Tom, 15, and Marin, 9.

"They're all showing signs, although it would never be picked up unless you were looking for it."

She and her two sons now have implanted cardiac defibrillators to help regulate their heart rhythms, and all four children are on beta-blockers to reduce the risk of arrythmia.

The Claytons were last night at celebrations marking development of the test and its availability through LabPLUS at Auckland City Hospital. Also there were other families of sudden cardiac victims, and representatives from Auckland District Health Board, the university, and the charitable organisation Cure Kids, which funded research and clinical testing.

Associate Professor Andrew Shelling, of the university's faculty of medical and health sciences, said the team was excited that cardiac specialists were keen to use their test.

"We hope the use of this, and future tests, will reduce the incidence of sudden death dramatically."


SUDDEN DEATH

* Each year, around 100 New Zealanders under the age of 40 die suddenly and unexpectedly.

* About 15 per cent of sudden deaths in 1 to 35-year-olds and at least 10 per cent of Sudden Infant Death Syndrome cases are thought to be attributable to Long QT syndrome.

* The syndrome refers to an abnormality of the heart's electrical system, due to defects in cell structures. These defects can cause very fast heart rhythms which lead to sudden loss of consciousness and may cause death.