Which auscultatory finding is classic for acute pericarditis?

• A. Pericardial friction rub
• B. Wheezing
• C. Diminished breath sounds
• D. S3 gallop

Answer: (A)

Acute pericarditis causes the inflamed pericardial layers to rub against one another with each heartbeat, producing a distinctive friction rub. This sound is high-pitched and scratchy, best heard at the left lower sternal border, and it’s most noticeable when the patient leans forward and exhales. The friction rub can be transient and may have components that reflect the different phases of the cardiac cycle, which is why clinicians often listen carefully in that position and with the patient breath-holding.

Wheezing points to airway narrowing or bronchospasm, not pericardial inflammation. Diminished breath sounds suggest reduced air entry or an issue like a pleural effusion or pneumothorax. An S3 gallop signals volume overload or reduced ventricular compliance, not pericardial inflammation. So the classic auscultatory finding for acute pericarditis is the pericardial friction rub.