AN American passenger who suffered from heart problems on a flight from Shanghai to the US was given emergency assistance by a Shanghai doctor who was on the same plane.

The 70-year-old American heart patient, whose name was not given, was on flight UA836 from Shanghai to Chicago on Thursday. Four hours after the flight took off, he started to sweat and complained of discomfort in his chest.

The passenger told the crew that he had received treatment for atrial fibrillation, a type of arrhythmia, about a year ago.