Here a child in Nepal drinks from a well containing water contaminated with arsenic, which can lead to abnormal heart beat, blood vessel damage and cancer, among other ill effects.

For a variety of reasons, something - such as a structural heart defect - causes the heart to beat out of control. This abnormal heart rhythm is known as ventricular fibrillation.

We are looking to see how many awakenings they've had, but very importantly we also are looking at other problems with the heart beat, or looking for any kind of abnormal brain wave activity.