THE SIGNIFICANCE OF BIFASICULAR BLOCK (RIGHT BUNDLE BRANCH BLOCK PLUS LEFT POSTERIOR FASCICULAR BLOCK) IN ADULTS <40 YEARS OLD

A bifascicular block involving the right bundle branch (RBBB) and left posterior fascicle (LPFB) is a rare ECG abnormality thought to imply significant disease of the cardiac conduction system. We sought to retrospectively establish a cohort with this ECG abnormality and evaluate for progression of