What are the areas of auscultation for a pericardial rub?

Areas of Auscultation for Pericardial Rub

The pericardial friction rub is best heard at the left lower sternal border, with the patient sitting upright and leaning forward while briefly holding their breath. 1

Optimal Auscultation Location

• The left lower sternal border is the primary and most prominent location for detecting a pericardial friction rub 1
• The rub may be audible across multiple precordial areas, but the left lower sternal border consistently provides the highest yield 1
• In some cases, the friction rub can be heard along the lower left sternal border extending to adjacent precordial areas 2, 3

Optimal Patient Positioning

• The patient should be positioned sitting upright and leaning forward to maximize detection of the pericardial rub 1
• This position brings the heart closer to the anterior chest wall and minimizes interfering lung sounds 1
• Have the patient briefly hold their breath during auscultation to eliminate respiratory sounds that may obscure the rub 1
• While the sitting-leaning-forward position is generally optimal, the friction rub can occasionally be more pronounced when the patient is supine, so both positions may be tried 1
• The left lateral decubitus position may also accentuate the rub in some patients 4

Clinical Characteristics and Detection Challenges

• The pericardial friction rub can be mono-, bi-, or triphasic in character, with the triphasic rub being most characteristic 2, 1
• The rub is highly specific but transient, being audible in only approximately one-third of patients with confirmed acute pericarditis 2, 1
• The friction rub can disappear and reappear during the course of pericarditis, making multiple auscultatory examinations necessary 2, 1
• The sound is often described as a "sandpaper-scratching" quality 4

Important Clinical Caveats

• The absence of a friction rub does not exclude the diagnosis of pericarditis, as it is only audible in less than one-third of confirmed cases 1
• When a friction rub is present in the setting of acute myocardial infarction accompanied by persistent pain, hypotension, or nausea, urgent echocardiography is indicated to rule out complications 1
• The presence of a pericardial friction rub is one of four key diagnostic criteria for acute pericarditis (along with characteristic chest pain, ECG changes, and pericardial effusion), with at least two criteria required for diagnosis 1