A British project is saving tiny lives around the globe by offering some of the poorest families live-saving surgery and tackling the developing world's hidden killer - congenital heart disease.

In under three years the Little Hearts project has taken volunteer specialists and surgery teams to almost 600 desperately-ill children who otherwise would stand little chance of living past adolescence and whose relatives could never afford to pay.

The teams work flat out to screen patients to find the most suitable for treatment, then carry out as many as seven open heart operations a day to save as many lives as they can in the time available.

They have previously been to Morocco, Mauritania, Sudan and the latest mission was a seven-day trip to Bangladesh.

Project manager Kabir Miah, 46, from Kingston-upon-Thames, South West London, explained how desperate mothers travelled on night buses for up to 12 hours to get their children screened to see if they were suitable for an operation.

He said: "These people are from rural, very poor backgrounds, they are agricultural workers living in tin huts.

"Their earnings are around £1 a day, they could never dream of paying for the surgery. They depend entirely on us to help them."

Before the team of fewer than 20 surgeons, anaesthetists and specialist nurses flew in to Dhaka from around the world, around 100 prospective patients were screened.

Of those, 81 received open heart surgery or intervention via a catheter.

The team comprises 11 nationalities, all trained at top medical universities, although none are British, which Little Hearts would like to change.

Paediatric cardiac surgeon Dr Mohammad Shihata, who works in Saudi Arabia, performed seven open heart surgeries a day.

He said: "Unfortunately, a lot of them would not survive into adulthood without surgery, and even if they did, they would have a very poor quality of life."

Little Hearts, which is backed by the UK charity Muntada Aid, wants to raise awareness about congenital heart disease in the developing world. In the West, it can be detected pre-birth and treatment at top-class hospitals is available.

Mr Miah said: "It is heart-rending, it is so sad. We just deal with as many operations as we can.

"Congenital heart disease is a major killer in the world. We can deal with it in the West.

"We are dealing with Aids, we are dealing with malaria...

"It is something kids are born with, some die, some live in agony until their teens or early 20s, but people are not talking about it."