What is the diagnosis when the QRS complex is longer than 0.12 seconds?

A QRS complex that is longer than 0.12 seconds typically indicates a Bundle Branch Block. This is a condition where there is a delay or obstruction in the electrical conduction through the bundle branches, which are important pathways for transmitting electrical impulses to the ventricles. When the conduction is disrupted, the ventricles do not contract simultaneously, resulting in a wider QRS complex on the electrocardiogram (ECG). This widening occurs because the impulse takes longer to travel through the ventricular myocardium, rather than following the normal conduction pathway.

In contrast, other conditions like Myocardial Infarction and Atrial Flutter may present with different ECG characteristics, and they do not specifically cause a QRS duration greater than 0.12 seconds. Ventricular Tachycardia can also feature a wide QRS complex, but it is typically associated with a distinct and often rapid heart rhythm that is different from the presentation of a Bundle Branch Block. Understanding these distinctions is crucial for accurate ECG interpretation and diagnosis.