This ECG has both second degree AV block with 2:1 block and second degree type I AV block. Note that intermittent P waves conduct to the ventricles on this ECG tracing, however it is clear that ...

Because the atrial rate is so fast, and the action potentials produced are of such low amplitude, P waves will not be seen on the ECG in patients with atrial fibrillation. At times, the P wave ...

These ECG voltage attenuations are of extracardiac mechanism, and impact the amplitude of QRS complexes, P-waves, and T-waves, occasionally resulting also in shortening of the QRS complex and QT ...