The second heart sound is not a single event but a dynamic, two-component signal modulated by respiration and cardiovascular hemodynamics. Careful attention to the intensity of A2 and P2 and the behavior of splitting during respiration allows clinicians to differentiate benign findings from critical conditions such as ASD, pulmonary hypertension, and severe aortic stenosis. When an abnormal S2 pattern is detected, echocardiography is the definitive next step.
An exaggerated split that persists through both phases but widens during inspiration. s2 heart sounds
A2 and P2 are separated enough to be heard as two distinct sounds. ⚠️ Abnormal S2 Findings The second heart sound is not a single