Pas president Datuk Seri Abdul Hadi Awang underwent heart valve replacement surgery at the National Heart Institute (IJN), here, today.

In a statement, IJN said he was currently warded at its Intensive Care Unit.

"The doctors are happy that the procedure progressed as anticipated and his vital parameters thus far are stable," IJN said.

It said his condition would be observed for the next few days as was routine in post-heart surgery.

"The next 48 hours is the crucial period in his post-operative care," it said, adding that Abdul Hadi would be under close observation by a team of doctors and nurses.

IJN said the three-hour heart surgery early this morning was performed by a panel of doctors led by senior consultant cardiothoracic surgeon and IJN chief executive officer Datuk Seri Dr Mohd Azhari Yakub, head of Cardiothoracic Surgery Datuk Seri Dr Jeffrey Jeswant Dillon and deputy head of the Anaesthesiology Department Datuk Dr Suhaini Kadiman.

It said Abdul Hadi had been having increasing symptoms due to a leaking heart valve that had affected his daily activities.

"As such, doctors advised for a planned heart valve surgery," the heart institute said.