The QRS complex on an ECG represents ventricular depolarization, with wide or narrow complexes indicating various heart conditions. It is useful in diagnosing arrhythmias, ventricular hypertrophy, myocardial infarction, and electrolyte imbalances. Some supraventricular tachycardias may require treatment. The QRS complex is a specific sequence of deviations seen on a printout of an ECG, representing depolarization […]