Heart beat has a basic rhythm in which it beats. The infrequent skipped heart beat is not serious, but when there is a sustained heart rhythm abnormality, medical advice is immediately needed. Most people will have experienced so-called arrhythmias from time to time, in other words a missed heart beat, or a feeling of fluttering in the chest. Arrhythmias arise from a lack of co-ordination of the electrical activity which keeps the heart beat regular.
Doctors at the Mayo Clinic offer some advice on arrhythmias. A sustained arrhythmia does not arise in a healthy person - unless they have had an electric shock or use illicit drugs. Heart disease and heart deformities, on the other hand, can lead to sustained arrhythmia, and these can even be fatal. They may lead to shortness of breath, lightheadedness, chest pain or fainting. If you develop any such symptoms,consult the doctor immediately.