Fatal heart attacks claims more lives than lung cancer, breast cancer and AIDS combined but it seems that maths, not medicine, holds the key to preventing these deaths among young people.
About 200 Australians aged 25 to 34 years die each year from heart attacks caused by cardiac arrhythmia. Most are apparently healthy young men who die within five minutes of the initial symptoms -- a suddenly irregular or fast heartbeat.
But the challenge of designing a pacemaker capable of correcting a potentially fatal arrhythmia is mathematical, not medical, according to University of New South Wales researcher, Dr Adelle Coster.
"The goal is to make an implantable artificial pacemaker that can arrest an abnormal heart rhythm before it becomes fatal," she says. "The mathematical challenge is to describe the complex patterns of electrical, chemical and neurological signals that trigger a potentially fatal heart attack.
"An arrhythmia is like a short circuit to the heart's electrical system," says Dr Coster, who has a three-year Australian Research Council grant to untangle the problem. "It interrupts the heart's rhythmic contraction and relaxation so it doesn't pump the way it's supposed to."
This abnormal rhythm can occur when electrical signals in the heart trigger rapid (tachycardia), slow (bradycardia) or chaotic beating (ventricular fibrillation).
"Normally, the heart's four chambers contract in a coordinated way, with the signal beginning in the sinoatrial node, which is the heart's natural pacemaker," she says. "The signal then travels through a series of heart chambers and nodes but problems can happen anywhere on this pathway.
"Understanding how these signals get passed from cell to cell is a non-linear dynamical problem we can treat mathematically by solving numerous simultaneous equations."
Dr Adelle Coster - (bh) 02-9385 7048 (ah) 0411 156 015
Dan Gaffney - UNSW Science Media - 0411 156 015