This example shows persistent splitting of the second heart sound. Splitting varies between thirty milliseconds at peak expiration and sixty milliseconds at peak inspiration.
With normal physiologic splitting the second heart sound is not split at peak expiration. With persistent splitting, the second heart sound is split in both inspiration and expiration although the degree of splitting is reduced in expiration.
This type of splitting is associated with Right Bundle Branch Block a condition in which the electrical signal which causes contraction of the right ventricle is blocked.