Base Left: Widely Fixed Split Second Sound (S2)
Fixed splitting of the second sound refers to split sound which displays little or no respiratory variation. The two components making up the second sound occur in their normal sequence but the ventricles are unable to change their volumes with respiration. This finding is typical in congestive heart failure, cardiomyopathy, atrial septal defect, or ventricular septal defect.
The fixed split is heard best at base left with the diaphragm.
The sound you heard demonstrates a widely fixed split second sound. It was taken from a patient with an atrial septal defect.