Physiologically Split S2

Normally the higher pressure left -sided valves close first (mitral before tricuspid, aortic before pulmonic). This discordance is exaggerated by inspiration, allowing the human ear to perceive two distinct sounds. During inspiration, intrathoracic pressure drops and augments RV filling. As a result, more time is required for the RV to pump the higher volume of blood into the pulmonary artery, thus delaying pulmonic valve closure.
Card Tutorial

Patient 3

This patient has a physiologically split S2. (**This video has an extra sound in it and will need be re-rendered)