ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias

An arrhythmia is an irregular heart rhythm. Examples include atrial, junctional, and ventricular arrhythmias.

Firstly, atrial arrhythmias originate from foci within the atria, including premature atrial complexes, atrial fibrillation, and atrial flutter.

Premature atrial complexes are early electrical impulses from the atria, often caused by stress or caffeine, showing early P waves on the ECG.

Atrial fibrillation, often caused by heart failure, involves rapid atrial contractions with no distinct P waves.

Atrial flutter, often caused by coronary artery disease or hypertension, involves fast atrial rhythms and sawtooth waves.

Next, junctional arrhythmias originate near the atrioventricular node and are often caused by digitalis toxicity, present with early narrow QRS complexes or absent or inverted P waves.

Finally, ventricular arrhythmias originate from the ventricles. They are often caused by ischemic heart disease, including premature ventricular complexes, ventricular tachycardia, and ventricular fibrillation, which show wide QRS complexes or chaotic waveforms.