The cardiac unit will deal with emergency operations only

Swansea NHS Trust managers say they took the step - which is believed to be unprecedented - to give the 15 theatre staff time to recharge their batteries because of a heavy workload.

The rest of the cardiac unit will function as normal and patients who are affected will be contacted directly.

But appointments for procedures including angiograms and heart by-passes have been cancelled and only emergency heart surgery will be conducted at the unit which includes a surgical ward and two operating theatres.

Now as a result of a 60% increase in funding we've reduced waiting times so that people were not waiting more than 12 months and many less than 10 months Jane Hutt

Dr Dai Lloyd, Plaid Cymru AM for South Wales West, said cardiac staff in hospitals across south Wales had been working hard to reduce waiting lists.

"We have to recognise the phenomenal hard work of our nurses and doctors - particularly when there's been a waiting list initiative as regards getting cardiac waiting lists down.

"It's the same staff who have to work longer hours and weekends and there's going to be an element of exhaustion.

"The recent performance has been excellent, but it's down to the commitment of the staff involved as regards the waiting lists that have been in cardiac surgery in Wales.

"It's not (Welsh Health Minister) Jane Hutt who is carrying out the heart operations, it's the staff at Morriston and Cardiff in south Wales.

"We still have some of the longest waiting lists in Europe and we remain with phenomenal challenges in Wales as regards the health service."

But in a statement, Ms Hutt said cardiac waiting times had come down in Wales as a result of Welsh Assembly Government investment.

'Considerable pressure'

She added: "Four years ago people in Wales were going to Hammersmith hospital in London for cardiac surgery.

"Now as a result of a 60% increase in funding we've reduced waiting times so that people were not waiting more than 12 months and many less than 10 months.

"That is the result of the investment by the Welsh Assembly Government".

A spokesperson for Swansea NHS Trust said: "The cardiac operating team has been working under considerable pressure involving staff working over-time an additional hours.

"In order to allow staff to recover from these pressures it has been decided to limit activity to emergencies only for the next week.

"We are grateful to staff for all the hard work they have undertaken and hope that this will create some breathing space to allow them to recharge their batteries."