MANY common arrhythmias observed in both atria and ventricles are similar although the atrial types have a few important distinguishing features. Thus, so far as therapy is concerned, the atrial ...

The atrioventricular node (AV Node) is a bundle of conduction cells that regulate the communication of atrial electrical activity with ventricular electrical activity. The AV node has a long ...

Narrow QRS complexes occur regularly. This tracing suggests either atrial flutter or ventricular tachycardia. It is not atrial flutter, however. If it were, the QRS complexes occurring regularly would ...

Atrial fibrillation is the most common chronic arrhythmia. It is characterized by erratic atrial electrical activity with atrial rates of 400 to 600 beats per minute. The P wave is absent on the ...

The rhythm in Figure 1 has a subtle pattern—a narrow QRS complex with alternating short and long R-R intervals, resulting in paired QRS complexes. Careful observation of V1 in Figure 2 reveals tiny ...