What does a prolonged QRS complex indicate?

A prolonged QRS complex indicates possible ventricular hypertrophy or a bundle branch block due to the delayed conduction of electrical impulses through the ventricles. Normally, the QRS complex duration is less than 120 milliseconds, reflecting the timely contraction of the ventricles. When this duration exceeds the normal value, it suggests that there might be an underlying issue affecting the heart's ability to conduct impulses efficiently.

Ventricular hypertrophy can result from the heart working harder than normal, often due to conditions such as hypertension or valvular heart disease, leading to an increase in the muscle mass of the ventricles. This hypertrophy can disrupt the normal conduction pathways, resulting in a wider QRS complex.

On the other hand, a bundle branch block occurs when there is a blockage of electrical impulses in one of the branches that conduct signals to the ventricles. The right or left bundle branch may be affected, and the blockage leads to a slower impulse traveling through the affected side, which can manifest as a prolonged QRS complex as well.

This is in contrast to options indicating normal heart function, atrial fibrillation, or healthy heart tissue, which would not typically correlate with a prolonged QRS interval. Normal measurements would suggest efficient conduction and healthy myocardial tissue,