It gave the 700 swingers present a bit of a shock. But it didn't take too long for the fun and games to resume.
She's now had a stent fitted in one of her blocked arteries and is making a recovery. There have been a few jokes about her overdoing it in the frenzy of camp activities."
She is expected to be released from hospital later today.
A ring of steel surrounds the 'secret' swingers festival, leaving the site on lockdown.
Swingfields, which describes itself as the UK's only swingers' festival, set up 'covertly' on farmland near Upper Welland.
And the site is just 200 yards away from a scout camp with just a single-track road separating children from the adult-themed event.
Today participants of the event, which is said to attract around 700 revellers, were pictured coming in and out of the site, as strict security measures were put in place to protect those in attendance.
Some even covered up their number plates to avoid being identified.
There appears to be just one main entrance where the swingers can leave the location and security has been briefed to be extra stringent against those approaching the area.
"It's not quite Upper Welland, is it?" said Marjorie Stapleton, 87, who lives less than a mile from the festival site.
"It is slightly embarrassing and in just one year we have begun to get a reputation," added Mrs Stapleton, who first heard about swinging last year when she was watching a Louis Theroux documentary.
"It's unappealing," concluded Mrs Stapleton. "They are not young people. They are middle aged with big tummies. It is slightly dreadful. And there is something a bit frightening about it. It is the covert way they go about it. I don't like the secrecy."
