Heart is externally covered by two layers of pericardium . Pericardial space is formed between parietal and visceral layers of pericardium . It is a narrow space which is normally lubricated with pericardial fluid up to 25ml. When these two tissue surfaces come into contact , pathological rub takes place.It is heard whenever the pericardium is inflammed . Pericardial rub is a distinctive but uncommon clinical sign .
Common clinical conditions
- Acute pericarditis
- Uremic pericarditis.
- Rheumatic pericarditis
- Post myocardial infarction
Pericardium has two layers .
There are four possibilities for pericardial rub to take place.
The rub can occur
1.Between the two layers of pericardium
2.Between the visceral pericardium and the epicardial layer of heart*.
3.Between parietal pericardium and the chest wall
4.Pericardium can rub with the adjacent pleura( Pleuro pericardial rub )
The second and third mechanisms are very rare.
An update
We have realized one more possibility . Diaphragm forms the floor of the heart on which the hanging heart rests . Rubbing of pericardium over diaphragmatic surface is a beat to beat affair that lasts the entire life !. In inflammatory states of diaphragm especially the contagious ones from abdomen , can result in pericardio- diaphragmatic rubs .These rubs are almost impossible to hear clinically.
*The anatomic mystery : Is epicardium same as visceral layer of pericardium ?
Some anatomist feel that both are same entities. If that is the case myocardium can never split its relationship with visceral pericardium.But it is also a anatomical fact visceral pericardium engulfs the coronary artery and are located sub epicardially.
How many components of pericardial rub are clincally heard ?
Pericardial rub classically has three components. Systolic, mid diastolic, and pressytolic atrial components. Pericardial rubs are typically described as to and fro rub. Systolic component is most consistent. In atrial fibrillation mono component pericardial rub is heard.
Quality
Superficial , scratchy, high pitched ( Can also be low pitched)
Location
Left sternal border , left 2nd or 3rd space .Best heard in sitting , leaning forward in inspiration. Many times the rubs are transient and evanescent . Since it has multiple components it may be mistaken for added heart sound like S 3 or S 4.
What is the mechanism of pericardial rub in the immediate post MI phase ?
Presence of pericardial rub post MI indicate a transmural involvement or atleast significant epicardial involvement . Recognition of this is important as presence of pericardial rub increases the risk of rupture and hemorrhagic effusion if anticoagulants are used.
What is the relationship between pericardial effusion and pericardial rub ?
Generally it is said with the onset of effusion pericardial rub disappear.But this is not necessarily true.
Rubs after contusion chest and fracture ribs can be with the chest wall and may have no relationship with effusion.
Is pericardial rub a painful condition ?
Pericardial rub associated with acute inflammatory pathology is severely painful (like a pleuritis).But pericarditis associated with chronic inflammatory conditions are less often generate pain.The exact reason is not known.
What is pleuro pericardial rub ?
This clinical entity is poorly defined , often taught by veteran professors in clinical auscultation classes.It can be heard in the mid segment or diaphragmatic pleuritis with or without pericardial effusion in patients with atypical pneumonias.
It would appear to me that one of your illustrations shown here is incorrect (www.lausd.k12.ca.us). In the zoomed window, the labels for the visceral pericardium and parietal pericardium are tranpsosed.
Thank you for your comment .It was indeed an error.It has been corrected.Thanks again.
venkatesan
How many patients say they can feel the rub? I am an MD with pericarditis and can feel a velcro sensation just in the small area where the pericardium meets the chest wall in certain positions. I have read of other patients who blog the same sensation but cannot find it in the medical literature.
Dear Sir, Good evening,
I have come across a quote which reads like “The greatest danger mankind faces is not from bad forces ..per..se.. but from those apparently good men who collaborate with the bad knowingly or unknowingly.”
I am interested to put this quote for an editorial of our journal Medical Journal Armed Forces India (MJAFI). The editorial is on the current unethical publication practice and emerging threats of predatory journals. Kindly confirm if you are the author of this quote.
Warm regards
Col (Dr) J Debnath
Editor in Chief, MJAFI
Dear Dr Debnath,
Thank you for your comment.
I believe the quote is mine.
With regards.
Venkatesn
asante sana kwa majibu mazuri.nice answers