A split S1 is most commonly caused by which of the following?

UK PLAB 1
#1

A split S1 is most commonly caused by which of the following?

a. Inspiration b. Expiration

c. Atrial septal defect (ASD)

d. Ventricular septal defect (VSD)

e. Right bundle branch block (RBBB)

Ans: e. Right bundle branch block (RBBB)