What are rubs in the context of heart sounds?

In the context of heart sounds, rubs refer specifically to the coarse sounds that occur when the heart rubs against an inflamed pericardium, a condition known as pericarditis. When the pericardium, which is the fibrous sac surrounding the heart, becomes inflamed, the friction between its layers produces audible sounds that can be detected through a stethoscope. These sounds are typically described as scratchy or squeaky and are distinct from normal heart sounds.

The presence of rubs can indicate underlying conditions, such as viral infections, autoimmune disorders, or post-myocardial infarction complications. Therefore, understanding rubs as associated with pericardial inflammation is crucial for proper assessment and diagnosis in a clinical setting.