Bundle Branch Block refers to a defect of the heart's electrical conduction system that can be seen on an EKG.

• A. BBB
• B. CAD
• C. Cardiomyopathy
• D. Cardiomegaly

Answer: (A)

The main concept here is recognizing that a Bundle Branch Block is a defect in the heart’s electrical conduction system, specifically a delay or blockage in one of the ventricular bundle branches, which is why it is seen on an EKG. When one bundle branch is blocked, the ventricles depolarize more slowly and in an uncoordinated way, producing a widened QRS complex and characteristic patterns on the EKG. The term that matches this description is Bundle Branch Block, abbreviated as BBB, making it the best answer because it directly names the conduction-system abnormality described.

The other terms refer to different cardiac issues: coronary artery disease (CAD) involves blood flow to the heart muscle, cardiomyopathy is disease of the heart muscle itself, and cardiomegaly means an enlarged heart. None of these describe a conduction defect visible on EKG, so they don’t fit the scenario.