Finance Minister Heng Swee Keat looked his usual self at a pre-Cabinet lunch at the Istana yesterday, said Parliamentary Secretary for Culture, Community and Youth Baey Yam Keng.
But at about 5.30pm, Mr Heng, 54, collapsed at the Cabinet meeting.
A shocked Mr Baey told The New Paper: "He looked perfectly fine during lunch.
"I don't remember ever seeing him unwell or going on medical leave in the five years that we served Tampines together."
According to the Prime Minister's Office (PMO), Mr Heng's sudden stroke was due to an aneurysm - a localised weakening of a blood vessel.
He has undergone initial neurosurgery to relieve pressure in his brain due to the bleeding and the aneurysm was successfully closed, the statement said.
At press time, Mr Heng remained under close monitoring in the intensive care unit of Tan Tock Seng Hospital (TTSH).
Related: Heng in ICU after stroke
But he added that Mr Heng's family will need prayers and support as he undergoes critical procedures and treatment for the stroke.
The three of them are MPs of Tampines GRC and they were supposed to meet at 7pm yesterday to discuss the upcoming Tampines Hub.
Fellow Tampines MP Desmond Choo was also shocked at the news.
"We've never heard anything like this. To me, he's like Superman," said Mr Choo.
"The number of hours he works and the kind of attention span he has, it's amazing."
The 2012 Hougang by-election candidate recalled the days when he worked closely with Mr Heng, whom he sees as a fatherly figure and source of inspiration.
"During the by-election period, we would discuss issues until 2am and he would ask me to go home," said Mr Choo.
"'As a candidate, you need rest,' he would tell me while he continued working with activists. When I returned in the morning, at about 6.30am, he'd already be there."
He added that he and Mr Baey had given out carnations with Mr Heng over the weekend for Mother's Day.
"He has amazing energy," said Mr Choo.
"Even for us, who are younger, we are always amazed at where Mr Heng finds his energy from. Over the weekend, he was no different."
Mr Baey recalled that during the last few days of the 2015 General Election campaign, Mr Heng would sleep in the branch office.
"He figured that it would be easier and he could save time that way," said Mr Baey, adding that Mr Heng was very dedicated to the GRC.
But Home Affairs and Law Minister K Shanmugam posted on Facebook yesterday that he had been working closely with Mr Heng on a number of things and could see that he was very tired.
"I have been telling him that he was overworking so much that it will affect his health," said Mr Shanmugam.
"He was carrying an incredible load, handling the Finance Ministry, various projects, including SG50, and the Committee for Future Economy, the committee responsible for charting our economic future."
Mr Heng's fellow Tampines GRC MPs can attest to his hard work and long hours.
Following news of his stroke, ministers and MPs took to Facebook to express their concern for the Finance Minister, whom Deputy Prime Minister Tharman Shanmugaratnam called "one of Singapore's finest sons and a leader with much promise".
PM Lee called Mr Heng a valuable member of his team.
A hashtag #prayforsweekeat was also created.
Former Senior Minister of State Lee Yi Shyan, who suffered a mini stroke a year ago, wished Mr Heng well.
"Swee Keat advised me to go slow and that doing 'less is more'. Yet he works so hard himself. I really wish he will recover soon and completely," Mr Lee posted on Facebook.
His finance portfolio will be taken over by DPM Tharman, the PMO said.
Others, like Health Minister Gan Kim Yong, wished Mr Heng a speedy recovery.
But with Mr Heng's many responsibilities on top of his ministerial role, including chairing the Future Economy Committee, how would his condition affect the Cabinet?
Political analyst Eugene Tan compared Mr Heng's stroke to then-DPM Lee Hsien Loong's diagnosis of lymphoma in 1992.
But Associate Professor Tan thinks that in Mr Heng's case, there might be no noticeable impact on the Government in the short term as there are ministers who can cover for him while he recuperates.
Labour chief Chan Chun Sing and Acting Minister for Education (Higher Education and Skills) Ong Ye Kung, who are also in the Future Economy Committee, can step up to take on Mr Heng's responsibilities.
In the long term, however, his condition will put a spotlight on leadership renewal and succession, said Prof Tan, a law don at Singapore Management University.
"Mr Heng is a core member of the fourth generation leadership. His sudden stroke could potentially throw a spanner in the works.
What is stroke
Mr Heng's stroke may be 'major'
There is a saying among neurologists: Time is brain.
"The quicker we get treatment, the more brain we save, the less the disability suffered," said Dr Charles Siow.
There is a critical time window of 4½ hours from the onset of stroke symptoms, which can influence recovery from a stroke, the neurologist at Siow Neurology, Headache And Pain Centre told The New Paper.
The window can stretch to six hours if certain instruments are used to pick out clots.
"The most immediate response is to either call an ambulance or go straight to the A&E (Accident and Emergency) department, where neurologists - who can deal with strokes - are present.
"If there is early treatment, some patients may have full recovery," he said.
For Finance Minister Heng Swee Keat, the onset of stroke symptoms will be 5.34pm, when he collapsed, Dr Siow explained.
For a patient to collapse from a stroke, it must have been a major one, he added.
"For more minor strokes, one may have slurred speech but can still move around and sit down and express their thoughts...
"Most of the time, a stroke affects the brain. A patient may become unconscious after collapsing, but his organs should continue to function - unless the stroke is due to a clot in the heart," said Dr Siow.
In Singapore, stroke is the fourth leading cause of death.
Most victims will survive a stroke, some with varying levels of disability, but a certain percentage of stroke patients will die, Dr Siow said.
BY THE NUMBERS
l Percentage of patients who have disability three months after a stroke: 63 per cent
l Percentage of total deaths in Singapore caused by stroke: 10 to 12 per cent
l New stroke cases in Singapore every day: 26
This article was first published on May 13, 2016.
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