Pericardial friction rub
A characteristic three-component scratchy sound heard on auscultation in patients with pericardial inflammation.
Full Definition
A pericardial friction rub is a pathognomonic auscultatory finding in acute pericarditis, characterized by a high-pitched, scratchy, or grating sound that results from the friction between inflamed visceral and parietal pericardial surfaces. The classic rub has three components corresponding to different phases of the cardiac cycle: atrial systole, ventricular systole, and early diastole (ventricular filling). However, commonly only two or even one component may be audible. The rub is best heard with the diaphragm of the stethoscope at the left sternal border and may be accentuated when the patient sits up and leans forward or during inspiration. The presence of a pericardial friction rub is diagnostic of pericarditis, though it may be transient and present in only about 60% of patients with acute pericarditis. The rub typically disappears as inflammation resolves or if significant pericardial effusion develops.
Usage
Usage note: May be confused with pleural friction rub, but pericardial rub continues during breath-holding while pleural rub does not.
In Context
- "Physical examination revealed a three-component pericardial friction rub at the left sternal border." — Emergency department assessment
- "The pericardial friction rub disappeared after initiation of anti-inflammatory therapy." — Cardiology follow-up note