Abertawe Bro Morgannwg University Health Board says many of the people it has been treating have cardiac problems or have suffered a stroke. Many are over the age of 85.
The health board says it has brought in extra staff, and put on extra beds, to deal to with its A&E departments being exceptionally busy.
It says most routine operations have been postponed.
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The charity says the increase is partly due to people calling for help sooner, instead of attempting to rescue themselves.
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A worker at Prince Charles Hospital in Merthyr Tydfil who stole NHS property and then sold it on eBay is given suspended jail sentence.