Trifascicular block is used to describe the combination of right bundle branch block, with both left anterior fascicular block and left posterior fascicular block.
Trifascicular Block (QRS ≥ 120 ms)
Combination of RBBB + LAFB + LPFB
Learn about different types of blocks using these links:
Unifascicular Block
Bifascicular Block
Left Bundle Branch Blocks
Right Bundle Branch Blocks
Left Anterior Fascicular Block
Left Posterior Fascicular Block