Signs of complete heart block

The atrial rate is approximately 100 bpm. The ventricular rate is approximately 40 bpm. The two rates are independent; there is no evidence that any of the atrial impulses are conducted to the ventricles. [Source]

Two ECG strips obtained in the same patient simultaneously (each represents a different vector of the heart’s electrical conduction), demonstrating complete AV block (also called 3rd degree heart block). The solid arrows point to P waves, representing atrial electrical conduction originating from the sinus node. The dashed arrows denote electrical conduction in the ventricles (QRS complexes). Note that the P waves are not related to the QRS complexes, demonstrating that the atria are electrically disconnected from the ventricles. The QRS complexes represent an escape rhythm arising from the ventricle. [Source]

Digoxin Toxicity

Digitalis is a medication prescribed to certain heart patients. Digitalis toxicity is a complication of digitalis therapy, or it may be occur when someone takes more than a large amount of the drug at one time. (This is called an acute ingestion.)

The most common prescription form of this medication is called digoxin.

Digitoxin is another form of digitalis.