The same Malaysian surgeon who performed the operation on Tun Dr Mahathir 18 years ago will lead the team.

Tun Dr Mahathir, 82, has suffered three mild heart attacks over the past 10 months.

'He chose to go for the surgery. It is not induced by any heart attacks or anything like that. He is absolutely fine,' Mr Sufi Yusoff, an aide to Tun Dr Mahathir, told The Straits Times. He declined to give more details.

Tun Dr Mahathir was admitted to the National Heart Institute on Sunday in preparation for an elective coronary bypass surgery, the institute said in a statement yesterday.

It will be Tun Dr Mahathir's second bypass. The first was done in 1989.

Cardiac surgeon Tan Sri Dr Yahya Awang, who performed the first bypass, will head the surgery again.

Tun Dr Mahathir's daughter Marina Mahathir wrote in her blog yesterday that the team will also 'have the expert hands of Dr Hartzell Schaff, chief cardiac surgeon at the Mayo Clinic in the US'.

Tun Dr Mahathir had undergone tests two weeks ago which led to the decision for another bypass, she said.

He had a check-up in 2005 but surgery was ruled out then.

'However, after three episodes in fairly quick succession since, this decision was re-looked at,' wrote Datin Paduka Marina.

'At 82, he is probably the oldest person to have a redo in Malaysia...but...he's tough, so God willing, all will be fine.'

The health of Tun Dr Mahathir is closely watched because he remains an influential political figure.

Several dozen Muslims held special prayers for him in a downtown Kuala Lumpur mosque yesterday evening.

Dr Yahya was the first local surgeon to perform a major operation on a head of the government.

'The operation may have prolonged the life of the prime minister but it certainly shortened mine,' he quipped in an interview with the New Straits Times daily in 2003.