Can you be 'dead' for 78 minutes?

The more details that emerge about Fabrice Muamba, the more amazing his story becomes.

The latest has seen the Bolton footballer labelled the "miracle man".

The 23-year-old collapsed on the pitch during the FA Cup tie against Tottenham at 18:13 GMT on Saturday, but it was not until 19:31 that his heart started working again.

He was - according to Bolton's club doctor - "in effect dead" during that 78 minutes.

But how is this possible?

The full details of what happened to him have yet to emerge.

But the most likely explanation - and one suggested by those involved in his care - is that while his heart stopped working, it retained some form of life.

The cardiac arrest he suffered meant his heart was not contracting and therefore pumping blood around his body.

However, even when this happens, some electrical activity can still be taking place within the heart.

If this was the case, one of several things could have been happening.

Bolton Wanderers club doctor Jonathan Tobin

The heart could have developed a severely abnormal rhythm, known as either ventricular fibrillation - where it shakes like a jelly - or ventricular tachycardia - where it is out of control.

The third explanation is that it has developed pulse-less electrical activity whereby there is an organised rhythm but no heart contractions.

In some cases, the state of the activity can interchange between the three.

The important thing in such cases is to start CPR quickly.

This artificially pumps the blood round the body, buying medics time to work out how to get the heart working properly.

Fabrice Muamba may still be in intensive care, but nonetheless not everyone is as lucky as him.

About 100,000 people a year in the UK die after having a sudden cardiac arrest.

Many of those will have collapsed in places where help is not to hand.

It is why in recent years a campaign has been under way to place more defibrillators in community settings.

Hundreds have already been placed in train stations, shopping malls and, of course, football grounds.

But there are still not enough, according to the Arrhythmia Alliance.

Truddie Lobban, the charity's founder, says: "The problem is that it is still very patchy. There are more than there used to be, but I would like to see them as common as fire extinguishers.

"We need them in schools, outside churches and on every high street.

"You don't have to be an expert to use them. They are automated and explain to the user how they work.

"They can make the difference between life and death."

Every minute delay in starting CPR reduces the chances of survival by 10%.

In this respect, the 23-year-old was lucky.

Pitch-side at White Hart Lane were a team of fully-trained and equipped medics.

What is more, a cardiologist was in the crowd and was soon by Muamba's side lending help.

It meant he received almost immediate attention.

But CPR alone is not enough. That only gives someone suffering a cardiac arrest a 5% chance of survival.

While he lay stricken on the pitch, the footballer was given oxygen and three shocks using a defibrillator.

The aim of that is to try to get the heart working again.

He was soon transferred to a waiting ambulance and rushed off to hospital.

In total he received another 12 shocks before his heart started working properly.

But was he really dead?

Spurs fan Dr Andrew Deaner is a cardiologist who ran on to the pitch to help Muamba

"I would say his life was in the balance," says Cathy Ross, of the British Heart Foundation.

"You can have a cardiac arrest and there be no electrical activity. But when this happens it is very hard to resuscitate someone.

"The people caring for him must have been getting some kind of response, otherwise you don't continue CPR for that long.

"But when there is something, you keep going. Seventy-eight minutes is a long time, but it's not unheard of."

If you want to find out how you could help someone who has a cardiac arrest, the British Heart Foundation runs a training course called Heart Start.