Base Left: Widely Split Second Sound (S₂)

The normal physiological split second sound can be accentuated by conditions that cause an abnormal delay in pulmonic valve closure. Such a delay may be due to increased volume in the right ventricle as compared with the left (atrial sseptal defect, or ventricular septal defect); chronic right ventricular outflow obstruction (pulmonic stenosis); acute or chronic dilatation of the right ventricle due to sudden rise in pulmonary artery pressure (pulmonary embolism); electrical delay or activation of the right ventricle (right bundle branch block); decreased elastic recoil of the pulmonary artery (idiopathic dilatation of the pulmonary artery).

The wide split has a duration of .04-.05 seconds compared to the normal physiological split of .03 seconds. It is best heard at base left with the diaphragm.

The sound you heard is a widely split second sound. The split is taken out occasionally to allow for comparison of the normal with the abnormal.