Left anterior fascicular block

This code represents a conduction abnormality in the heart where the electrical impulse is blocked or delayed in the left anterior fascicle of the left bundle branch. This results in a characteristic pattern on an electrocardiogram (ECG) indicating a delay in the depolarization of the anterior and superior portions of the left ventricle.

Use this code when documentation explicitly states "left anterior fascicular block" or "left anterior hemiblock" based on ECG findings. This condition is often asymptomatic but can be associated with underlying heart disease.

• Ensure the documentation specifies "left anterior" to differentiate from other fascicular blocks.
• Do not confuse with complete left bundle branch block (LBBB) or right bundle branch block (RBBB).
• Code any underlying cardiac conditions contributing to the block, such as ischemic heart disease, as primary if applicable.