When a doctor listens to the heart of a person with a heart murmur, they may hear a whooshing, swishing, humming, or rasping sound. This is due to rapid, turbulent blood flow through the heart.

An S4 heart sound is a low-pitched sound that occurs toward the end of the diastole. In some cases, an underlying health condition, often one affecting the left ventricle, may cause the S4 heart sound ...

An S4 heart sound cannot be present during atrial fibrillation (atrial kick is required). An S3 heart sound cannot be present in the setting of severe mitral stenosis. An S3 heart sound can be present ...