Persistently Split S2

A persistently split S2 describes the presence of a split S2 on expiration that widens further upon inspiration. The most common cause of a persistently split S2 is a right bundle branch block, but it can occur whenever there is prolonged right ventricular ejection, such as outflow obstruction, pulmonary hypertension, or increased RV output.

Card Tutorial

Patient 1

This is an older man with severe pulmonary hypertension and a right bundle branch block. Note the persistently split S2 as well as a split S1.

Persistently Split S2

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