Phonocardiogram showing paradoxical splitting of S2 in aortic stenosis

Electrocardiogram and phonocardiogram of aortic stenosis due to valvular calcification as heard at the 3^rd left intercostal space. S1 (mitral and tricuspid valve closure) is followed by a mild systolic ejection murmur of aortic stenosis. In contrast to normal, aortic valve closure is very delayed, and it occurs after closure of the pulmonic valve, accounting for the paradoxical splitting (S2 becomes single with inspiration).