Atrial fibrillation occurs when action potentials fire very rapidly within the pulmonary veins or atrium in a chaotic manner. The result is a very fast atrial rate — about 400 to 600 beats per ...

The QRS complex is irregular and coarse "fibrillatory waves" are present (see atrial fibrillation review by clicking below) indicating the presence of atrial fibrillation. There is quite a slow ...