The difference that can be found are:
Nodal rhythm: you can see the absence of the p wave (the first electric signal of an ECG)
Heart block: Heart block is a delay in the conduction of the electrical impulse through the atrioventricular node, the His bundle, or both branches, all located between the atria and the ventricles. There is a gap between the p and the rest of the ECG.
Atrial flutter: Designate atrial fibrillation whose amplitude, relative regularity and low frequency of the ripples are close to atrial flutter. Nevertheless, the f-waves are slightly irregular and rather positive in DII-III-VF shunts (unlike common atrial flutter). This aspect is in favor of a rather recent FA.
Atrial fibrillation: We observe:
*An absence of sinus wave P
*Auriculograms that vary anarchically in amplitude, shape, and frequency. They form a ripple of the baseline that may be relatively broad or barely visible (in aged forms), sometimes observed selectively in V1. These f waves can be confused with artifacts.
*Irregular RR intervals.
Ventricular fibrillation: an Anarchic electrical activity of the ventricular myocardium. The resulting total desynchronization is responsible for circulatory arrest (asystole).
