November 25, 2009
STICKING a needle through a living heart is always a tense moment. The tension was even higher yesterday, as physicians at Southern Health’s MonashHeart performed an Australia-first operation that could improve the lives of hundreds of thousands of people with heart arrhythmia.
Watched by experts from around the country, Dr Jeffrey Alison carefully pressed his catheter needle into the septum separating the top two chambers of the patient’s heart.
”Crossing the septum can be stressful,” Dr Alison admitted after the operation. But the trickiest bit was yet to come.
Ultrasound and video X-ray monitors showed the membrane ”tent”, and then gave way, allowing the tiny catheter tube through to its ultimate destination – a little pouch in the opposite corner of the heart called the left atrial appendage.
This appendage is sometimes called the ”heart’s appendix”, an apparently useless nook that usually causes no trouble. But in patients with atrial fibrillation, where the upper chambers of the heart beat irregularly, dangerous blood clots can form in the appendage. If those clots come loose, they are perfectly placed to rush to the brain and cause a stroke.
As the population ages, more and more people face this problem: atrial fibrillation will affect one in four people over the age of 40. Once people pass age 65, more than one in 10 will have a stroke as a result of the condition. Until now, the only treatment was the blood-thinning drug warfarin.
”Warfarin reduces the risk of stroke, but because the blood is thinned there is a cumulative bleeding risk,” Dr Alison, MonashHeart’s head of cardiac rhythm management said. ”The older you get, the higher the risk of bleeding complications, some of which can be lethal, such as cerebral haemorrhage.”
For the first time, now there is a proven alternative: called the WATCHMAN device, it is a little jellyfish-like structure made of titanium that expands to fill the appendage and prevent clots from coming loose.
”You are trading the short term risk of an invasive procedure – which can be managed effectively – for the long-term risks of warfarin,” Dr Alison said.
Patients are also freed from the need for regular blood tests.
Dr Alison said placing the WATCHMAN device was the hardest part of the operation.
”The appendage has thin walls and is easy to perforate,” he said. ”You are working in a part of the circulation that communicates with the rest of the body, including the brain. There is a risk of [causing a] stroke. It’s all about being fastidious in these phases, taking it bit by bit.”
Making it even harder is the fact that everyone’s appendage is different – some are shaped like a windsock, some like broccoli, another might be angled like a chicken wing.
To make sure of a tight fit, the WATCHMAN device comes in a variety of sizes, from two centimetres to more than three centimetres in diameter.
Dr Alison was guided through the operation by Saibal Kar, an expert in the procedure from Cedars-Sinai Medical Centre in Los Angeles. Physicians from hospitals in Victoria, Brisbane and Sydney watched the first three operations yesterday, so they can practise in coming days.
Dorothy Clayton, 67, yesterday became the first patient to get the device in Australia.
”I feel very honoured,” she said.