A pericardial friction rub, also pericardial rub, is an audible
medical sign
Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showi ...
used in the
diagnosis
Diagnosis is the identification of the nature and cause of a certain phenomenon. Diagnosis is used in many different disciplines, with variations in the use of logic, analytics, and experience, to determine " cause and effect". In systems engin ...
of
pericarditis. Upon
auscultation, this sign is an extra
heart sound of to-and-fro character, typically with three components, two
systolic and one
diastolic
Diastole ( ) is the relaxed phase of the cardiac cycle when the chambers of the heart are re-filling with blood. The contrasting phase is systole when the heart chambers are contracting. Atrial diastole is the relaxing of the atria, and ventricu ...
.
It resembles the sound of squeaky leather and often is described as grating, scratching, or rasping. The sound seems very close to the ear and may seem louder than or may even mask the other heart sounds. The sound usually is best heard between the
apex
The apex is the highest point of something. The word may also refer to:
Arts and media Fictional entities
* Apex (comics), a teenaged super villainess in the Marvel Universe
* Ape-X, a super-intelligent ape in the Squadron Supreme universe
*Apex, ...
and
sternum
The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. Sha ...
but may be widespread.
Cause
The
pericardium
The pericardium, also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. It has two layers, an outer layer made of strong connective tissue (fibrous pericardium), and an inner layer made o ...
is a double-walled sac around the
heart
The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to t ...
. The inner and outer (visceral and parietal, respectively) layers are normally lubricated by a small amount of pericardial fluid, but the
inflammation
Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...
of pericardium causes the walls to rub against each other with audible friction. In children, rheumatic fever is often the cause of pericardial friction rub. Pericardial friction rubs can also be heard in pericarditis that is associated with uremia or post-myocardial infarction.
Differential diagnosis
Pericardial friction rub is one of several, similar sounds. A
differential diagnosis may be possible, or not, depending upon the number of components that are audible. Pericardial friction rub may have one, two, or three audible components, whereas the similar
pleural friction rub ordinarily has two audible components. One- and two-component rubs are ambiguous. A three-component rub distinguishes a pericardial rub and indicates the presence of pericarditis. Also, a pleural rub can only be heard during inspiration , whereas, the pericardial rub can be heard even after cessation of breathing. Pleural rub creates pain mostly on the lateral part of the chest wall, whereas pain due to pericardial rub is always central in location. The intensity of pleural rub is increased on pressing the diaphragm of the stethoscope over the affected area, whereas there is no such change in case of a pericardial rub.
References
See also
*
Precordial exam
{{Cardiovascular system symptoms and signs
Audible medical signs