​A"MINI PARACHUTE" implanted in the heart of Mr Cheong Ching Chuan, who has suffered from an irregular heartbeat for almost 30 years, may save the 70-year-old retiree from a stroke in future.

Implanted in the upper chamber of his heart by National Heart Centre (NHC) doctors in October, the thumb-sized device prevents blood clots from leaving the area, clogging up an artery and causing a stroke.

The device, called the Watchman device, gives hope to patients with an irregular heartbeat who are at risk of strokes but are unsuitable for the standard treatment of blood thinners.

When the heart beats irregularly, blood clots can form in a small appendix-like pocket in the heart’s left chamber, which are then perfectly poised to travel to the brain or other parts of the body and cause a stroke.

Around half of all patients with an irregular heartbeat worldwide have to be on anticoagulants, such as warfarin, for the rest of their life, said NHC’s medical director, Associate Professor Koh Tian Hai.

While warfarin is still the most effective drug for stroke prevention, side effects include an increased risk of bleeding, said NHC’s senior consultant and director, Dr Teo Wee Siong.

He added: "While warfarin is easier to administer and is cheaper, some patients cannot take it as they are prone to falls or may have higher risk of internal bleeding. Right now, we just give them a milder drug and hope nothing happens. It’s not as effective – they sometimes still get strokes."

Another method to prevent blood clots in the heart appendage is to surgically seal it. But this is more invasive and does not always completely seal the area, said Prof Koh.

So, the Watchman device will be an important alternative treatment for this group of patients, estimated to number around 100 newly-diagnosed patients a year, the doctors said.

Doctors predict that the number of patients here – about 1 per cent of the population – will rise almost three-fold over the next 50 years, as the population ages.

In the two-hour procedure, which costs around $4,000, the device is delivered to the heart via a catheter inserted through a vein in the groin. Once in the right position, the device is expanded and lodged there.

After a period of around six weeks, it seals off the appendage, preventing blood clots from travelling to the brain or other parts of the body.

The chamber walls of the area risk being perforated, but this was "highly unlikely", said Prof Koh.

Recent clinical trials on the Watchman device in the United States and Europe have been promising, he added.

However, Prof Koh and Dr Teo stressed that such devices will not replace warfarin – the main anti-coagulant of choice – just yet, due to the lack of long-term data on the device’s safety and effectiveness.

Should future studies prove successful, the NHC will consider increasing its use in more patients or even using it to replace warfarin, they said.

Private cardiothoracic surgeon Tan Yong Seng agreed that long-term data is needed for this technique.

He said: "The advantage of this technique would depend on how effective the blockage of the area by the device is."

Mr Cheong, who can now stop taking warfarin after over 10 years, has no regrets.

He said: "When on warfarin, there were times I used to bend over to pick something up and start bleeding from the nose. With this device, I feel more reassured that I won’t get a stroke."

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