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  Image          = Jugular venous pressure 001.jpg|
  Caption        = Method to examine jugular venous pressure. <br> Image courtesy of Charlie Goldberg, M.D., UCSD School of Medicine and VA Medical Center, San Diego, California|
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{{CMG}}
{{CMG}} {{AE}} {{Mitra}} {{MC}}
{{SK}}  Jugular venous distention; elevated JVP; JVD; elevated neck veins; distended neck veins


==Overview==
==Overview==
The '''jugular venous pressure''' (JVP, sometimes referred to as ''jugular venous pulse'') is the indirectly observed pressure over the [[vein|venous system]]. It can be useful in the differentiation of different forms of [[heart disease|heart]] and [[lung disease]].
The '''[[jugular venous pressure]]''' ([[JVP]], sometimes referred to as ''[[jugular venous pulse]]'') is the indirectly observed pressure over the [[vein|venous system]]. It can be useful in the differentiation of various forms of [[heart disease|heart]] and [[lung disease]].


Classically three upward deflections and two downward deflections have been described. the upward deflections are the "a" (atrial filling), "c" (ventricular contraction and resulting bulging of tricuspid into the right atrium during isovolumic systole) and "v"= atrial venous filling. and the downward deflections of the wave are the "x"(tricuspid opens and ventricular filling occurs) and the "y" descent reflects filling of ventricle after tricuspid opening.
Classically three upward deflections (waves) and two downward deflections (toughs) have been described. The upward deflections are the "a" (atrial filling), "c" (ventricular contraction and resulting bulging of tricuspid into the right atrium during isovolumic systole), and "v" (atrial venous filling) waves, and the downward deflections are the "x"(when tricuspid opens and ventricular filling occurs) and the "y" descents (filling of ventricle after tricuspid opening).


The interpretation of JVP findings can be challenging and is becoming a lost art, as much of the subtle information previously obtained by careful observation of the JVP can now be gained easily with [[echocardiography]] and/or [[Electrocardiogram|EKG]].  Certain wave form abnormalities, include "''Cannon a-waves''", which result when the atrium contracts against a closed tricuspid valve, due to [[complete heart block]] (3rd degree heart block), or even in [[ventricular tachycardia]].  Another abnormality, "''c-v waves''", can be a sign of [[tricuspid regurgitation]].
The interpretation of [[JVP]] findings can be challenging and is becoming a lost art, as much of the subtle information previously obtained by careful observation of the [[JVP]] can now be gained easily with [[echocardiography]] and/or [[Electrocardiogram|EKG]].  Certain waveform abnormalities include "''[[Cannon a-waves]]''", which result when the atrium contracts against a closed tricuspid valve, due to [[complete heart block]] (3rd-degree heart block), or even in [[ventricular tachycardia]].  Another abnormality, "''c-v waves''", can be a sign of [[tricuspid regurgitation]].


An elevated JVP is the classic sign of venous hypertension (e.g. right-sided [[heart failure]]).  The paradoxical increase of the JVP with inspiration (instead of the expected decrease) is referred to as the [[Kussmaul sign]], and indicates impaired filling of the right ventricle.  The differential diagnosis of Kussmaul's sign includes [[constrictive pericarditis]], [[restrictive cardiomyopathy]], [[pericardial effusion]], and severe right-sided [[heart failure]].
An elevated [[JVP]] is the classic sign of venous hypertension (e.g. right-sided [[heart failure]]).  The paradoxical increase of the [[JVP]] with [[inspiration]] (instead of the expected decrease) is referred to as the [[Kussmaul sign]] and indicates impaired filling of the right ventricle.  The differential diagnosis of [[Kussmaul's sign]] includes [[constrictive pericarditis]], [[restrictive cardiomyopathy]], [[pericardial effusion]], and severe right-sided [[heart failure]].


==Assessment of Jugular Venous Distention==  
==Anatomy==
*'''Right and left [[internal jugular vein]]s ([[IJV]]s):'''
** Paired neck [[veins]] draining the head and neck.
** Originate from the [[dural venous sinuses]] and leave the [[skull]] via the [[jugular foramen]], then descend through the neck alongside and lateral to the [[internal carotid arterie]]s.
** Then join the [[subclavian vein]]s (at the base of the neck) to form the [[brachiocephalic vein]].
** The [[IJV]]s lies deep to the skin and soft tissues; therefore, they are not directly visible and identification only is possible via visualization of pulsations transmitted to the surface of the neck.
** Additionally, these blood vessels are under much lower pressure than the adjacent, pulsating [[carotid artery]]. It, therefore, takes a sharp eye to identify the relatively weak, transmitted venous impulses.


Assessment for distention of the right [[Internal jugular vein]] (IJ) is a difficult skill. Its importance lies in the fact that the IJV is in straight-line communication with the right atrium. The IJV can therefore function as a manometer, with distention indicating elevation of [[Central venous pressure]] (CVP). This in turn is an important marker of intravascular volume status and related cardiac function. The focus here is on simply determining whether or not Jugular Venous Distention (JVD) is present. A discussion of the a, c and v waves that make up the jugular venous pulsations can be found elsewhere. These are quite difficult to detect for even the most seasoned physician.
*'''Right [[internal jugular vein]]'''
**It directly Communicates with the [[right atrium]] via the [[superior vena cava]]
**The right [[IJV]] can therefore function as a manometer, with distention indicating an elevation of [[Central venous pressure]] ([[CVP]]).
**This in turn is an important marker of intravascular volume status and related cardiac function.


===Why is JVD so hard to assess?===
*'''Right and left [[external jugular vein]]s ([[EJV]]):'''
**These veins drain superficial [[scalp]] and face structures
**They descend the lateral neck, pass diagonally over the top of the [[sternocleidomastoid muscle]]s and empty into the [[subclavian veins]]
**The [[EJV]]s are valved, and not directly in the line with the [[right atrium]] or [[superior vena cava]]; therefore, are less preferred for estimation of [[JVP]] compared to the left [[IJV]].


The IJV lies deep to skin and soft tissues, which can provide quite a bit of cover. Additionally, this blood vessel is under much lower pressure then the adjacent, pulsating carotid artery. It therefore takes a sharp eye to identify the relatively weak, transmitted venous impulses.  
==Technique==
 
[[Image:Jvp-examination.jpg|left|thumb|Method to examine the JVP]]
*A classical method for quantifying the [[JVP]] was described by Borst & Molhuysen in 1952.<ref>{{cite journal | author = Borst J, Molhuysen J | title = Exact determination of the central venous pressure by a simple clinical method. | journal = Lancet | volume = 2 | issue = 7 | pages = 304-9 | year = 1952 | id = PMID 14955978}}</ref> It has since been modified in various ways. <ref name="Book1">{{cite book | last = Perloff | first = Joseph | title = Physical examination of the heart and circulation | publisher = People's Medical Pub. House | location = Shelton, CT | year = 2009 | isbn = 978-1-60795-023-3 }}</ref> <ref name="Book2">{{cite book | last = Bickley | first = Lynn | title = Bates' guide to physical examination and history taking | publisher = Wolters Kluwer | location = Philadelphia | year = 2017 | isbn = 9781469893419 }}</ref> <ref name="Book3">{{cite book | last = Zipes | first = Douglas | title = Braunwald's heart disease : a textbook of cardiovascular medicine | publisher = Elsevier/Saunders | location = Philadelphia, PA | year = 2019 | isbn = 978-0323463423 }}</ref>
 
*The patient is positioned under 45°, and the filling level of the [[jugular vein]] is determined. In healthy people, it is a maximum of several (3-4) centimeters above the [[sternum|sternal]] angle. Some physicians employ a ''venous arc'', an instrument to measure the [[JVP]] more accurately. A pen-light can aid in discerning the jugular filling level.
 
===Visualization of the [[JVP]]===
The [[JVP]] is easiest to observe if one looks ''along'' the surface of the [[sternocleidomastoid muscle]], as it is easier to appreciate the movement relative to the neck when looking from the side (as opposed to looking at the surface at a 90-degree angle). Like judging the movement of an automobile from a distance, it is easier to see the movement of an automobile when it is crossing one's path at 90 degrees (i.e. moving left to right or right to left), as opposed to coming toward one. Remember, tangential light is critical.


===A few things to remember:===
===A few things to remember:===


* Think anatomically. The right [[internal jugular vein]] (IJV) runs between the two heads (sternal and clavicular) of the [[sternocleidomastoid muscle]] (SCM) and up in front of the ear. This muscle can be identified by asking the patient to turn their head to the left and into your hand while you provide resistance to the movement. The two heads form the sides of a small triangle, with the [[clavicle]] making up the bottom edge. You should be able to feel a shallow defect formed by the borders of these landmarks. Note, you are trying to identify impulses originating from the IJV and transmitted to the overlying skin in this area. You can't actually see the IJV. The [[external jugular vein]] (EJV) runs in an oblique direction across the sternocleidomastoid and, in contrast to the IJV, can usually be directly visualized. If the EJV is not readily apparent, have the patient look to the left and valsalva. This usually makes it quite obvious. EJV distention is not always a reliable indicator of elevated CVP as valves, designed to prevent the retrograde flow of blood, can exist within this vessel causing it to appear engorged even when CVP is normal. It also makes several turns prior to connecting with the central venous system and is thus not in a direct line with the [[right atrium]].
*'''Think anatomically'''
* Take your time. Look at the area in question for several minutes while the patient's head is turned to the left. The carotid artery is adjacent to the IJV, lying just medial to it. If you are unsure whether a pulsation is caused by the carotid or the IJ, place your hand on the patient's radial artery and use this as a reference. The carotid impulse coincides with the palpated radial artery pulsation and is characterized by a single upstroke timed with systole. The venous impulse (at least when the patient is in sinus rhythm and there is no [[tricuspid regurgitation]]) has three components, each associated with the aforementioned a, c and v waves. When these are transmitted to the skin, they create a series of flickers that are visible diffusely within the overlying skin. In contrast, the carotid causes a single up and down pulsation. Furthermore, the carotid is palpable. The IJ is not and can, in fact, be obliterated by applying pressure in the area where it emerges above the clavicle.
**The right [[internal jugular vein]] (IJV) runs between the two heads (sternal and clavicular) of the [[sternocleidomastoid muscle]] ([[SCM]]) and up in front of the ear.
* Search along the entire projected course of the IJV as the top of the pressure wave (which is the point that you are trying to identify) may be higher than where you are looking. In fact, if the patient's CVP is markedly elevated, you may not be able to identify the top of the wave unless they are positioned with their trunk elevated at 45 degrees or more (else their will be no identifiable "top" of the column as the entire IJV will be engorged). After you've found the top of the wave, see what effect sitting straight up and lying down flat have on the height of the column. Sitting should cause it to appear at a lower point in the neck, while lying has the opposite effect. Realize that these maneuvers do not change the actual value of the central venous pressure. They simply alter the position of the top of the pulsations in relation to other structures in the neck and chest.
**This muscle can be identified by asking the patient to turn their head to the left and into your hand while you provide resistance to the movement.  
* Shine a pen light tangentially across the neck. This sometimes helps to accentuate the pulsations.
**The two heads form the sides of a small triangle, with the [[clavicle]] making up the bottom edge. You should be able to feel a shallow defect formed by the borders of these landmarks.  
* If you are still uncertain, apply gentle pressure to the right upper quadrant of the abdomen for 5 to 10 seconds. This elicits [[Hepatojugular reflux]] which, in pathological states, will cause blood that has pooled in the liver to flow in a retrograde fashion and fill out the IJV, making the transmitted pulsations more apparent. Make sure that you are looking in the right area when you push as the best time to detect any change in the height of this column of blood is immediately after you apply hepatic pressure.
**Note, you are trying to identify impulses originating from the [[IJV]] and transmitted to the overlying skin in this area. You can't actually see the [[IJV]].  
* Once you identify JVD, try to estimate how high in cm the top of the column is above the [[Angle of Louis]]. The angle is the site of the joint which connects the manubrium with the rest of the sternum. First identify the [[suprasternal notch]], a concavity at the top of the manubrium. Then walk your fingers downward until you detect a subtle change in the angle of the bone, which is approximately 4 to 5 cm below the notch. This is roughly at the level of the 2nd intercostal space. The vertical distance from the top of the column to this angle is added to 5cm, the rough vertical distance from the angle to the right atrium with the patient lying at a 45 degree angle.  
**The [[external jugular vein]] ([[EJV]]) runs in an oblique direction across the [[sternocleidomastoid muscle]] and, in contrast to the [[IJV]], can usually be directly visualized.  
**If the [[EJV]] is not readily apparent, have the patient look to the left and do a [[Valsalva manuver]]. This usually makes it quite obvious.  
**[[EJV]] distention is not always a reliable indicator of elevated [[CVP]] as valves, designed to prevent the retrograde flow of blood, can exist within this vessel causing it to appear engorged even when [[CVP]] is normal. It also makes several turns before connecting with the central venous system and is thus not in a direct line with the [[right atrium]].
*'''Take your time.'''
**Look at the area in question for several minutes while the patient's head is turned to the left.  
**The [[carotid artery]] is adjacent to the IJV, lying just medial to it.  
**If you are unsure whether a pulsation is caused by the [[carotid artery]] or the [[IJV]], place your hand on the patient's [[radial artery]] and use this as a reference.  
**The [[carotid impulse]] coincides with the palpated [[radial artery]] pulsation and is characterized by a single upstroke timed with [[systole]].  
**The venous impulse (at least when the patient is in [[sinus rhythm]] and there is no [[tricuspid regurgitation]]) has three components, each associated with a, c, and v waves. When these are transmitted to the skin, they create a series of flickers that are visible diffusely within the overlying skin.  
**In contrast, the [[carotid artery]] causes a single up and down pulsation.  
**Furthermore, the [[carotid artery]] is palpable, while the [[IJV]] is not palpable and can, in fact, be obliterated by applying pressure in the area where it emerges above the [[clavicle]].
*'''Search along the entire projected course of the [[IJV]] as the top of the pressure wave (which is the point that you are trying to identify) may be higher than where you are looking'''.  
**In fact, if the patient's [[CVP]] is markedly elevated, you may not be able to identify the top of the wave unless they are positioned with their trunk elevated at 45 degrees or more (else there will be no identifiable "top" of the column as the entire [[IJV]] will be engorged).  
**After you have found the top of the wave, see what effect sitting straight up and lying down flat has on the height of the column. Sitting should cause it to appear at a lower point in the neck while lying has the opposite effect. Realize that these maneuvers do not change the actual value of the central venous pressure. They simply alter the position of the top of the pulsations in relation to other structures in the neck and chest.
*'''Shine a penlight tangentially across the neck'''. This sometimes helps to accentuate the pulsations.
*'''If you are still uncertain, apply gentle pressure to the [[right upper quadrant]] of the abdomen for 5 to 10 seconds.'''
**This elicits [[Hepatojugular reflux]] which, in pathological states, will cause blood that has pooled in the liver to flow in a retrograde fashion and fill out the [[IJV]], making the transmitted pulsations more apparent.  
**Make sure that you are looking in the right area when you push as the best time to detect any change in the height of this column of blood is immediately after you apply hepatic pressure.
*'''Once you identify [[JVD]], try to estimate how high in cm the top of the column is above the [[Angle of Louis]]'''.  
**The angle is the site of the joint that connects the [[manubrium]] with the body of the [[sternum]]. First identify the [[suprasternal notch]], a concavity at the top of the manubrium.  
**Then walk your fingers downward until you detect a subtle change in the angle of the bone, which is approximately 4 to 5 cm below the notch.  
**This is roughly at the level of the 2nd [[intercostal space]].  
**The vertical distance from the top of the column to this angle is added to 5cm, the rough vertical distance from the angle to the [[right atrium]] with the patient lying at a 45-degree angle.
**The sum is an estimate of the [[CVP]]. Normal [[CVP]] is 7-9 cm.


The sum is an estimate of the CVP. However, if you can simply determine with some accuracy whether JVD is present or not, you will be way ahead of he game! Normal is 7-9 cm.
===The [[CVP]] vs the JVP===
 
The [[central venous pressure]] ([[CVP]]) lies approximately 5 cm above the middle of the [[right atrium]]. The  [[CVP]] is therefore estimated to be the [[JVP]] in cm plus 5 cm. Normally, the [[CVP]] is 5-9 cm of H2O.
(Images courtesy of Charlie Goldberg, M.D., UCSD School of Medicine and VA Medical Center, San Diego, California)


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Image:Elevated JVP.JPG|Elevated JVP</gallery>
Image:Elevated JVP.JPG|Elevated JVP</gallery>
</div>
</div>
(Images courtesy of Charlie Goldberg, M.D., UCSD School of Medicine and VA Medical Center, San Diego, California)


== Differential Diagnosis of Elevated Jugular Venous Pressure (Jugular Venous Distension)==
* [[Atrial fibrillation]]
* [[Bradycardia]]
* [[Cardiac Tamponade]]
* [[Cardiomyopathy]]
* [[Chronic Obstructive Pulmonary Disease]] ([[COPD]])
* [[Heart failure|Right heart failure]]
* [[Pericarditis|Constrictive pericarditis]]
* [[Goiter]]
* [[Heart block]]
* [[Hodgkin's Lymphoma]]
* [[Hyperdynamic circulation]] (e.g. in [[extreme anemia]])
* [[Hypervolemia]] or [[fluid overload]]
* [[Mediastinal emphysema]]
* [[Mediastinal neoplasm]]
* [[Pericarditis|Pericardial effusion]]
* [[Pulmonary hypertension]]
* [[Right atrial myxoma]]
* [[Right ventricular dilation]]
* [[Right ventricular myocardial infarction]]
* [[Superior Vena Cava Syndrome]]
* [[Tension pneumothorax]]
* [[Thymoma]]
* [[Tricuspid regurgitation]]
* [[Tricuspid stenosis]]
* [[Valsalva maneuver]]


Jugular vein distention is a classic sign of elevated venous pressure.
===Differentiation of the [[JVP]] from the [[carotid pulse]]===
[[Image:Jvp-vs-carotid.jpg|left|300px]]


==The CVP vs the JVP==
[[Pulse]]s in the [[JVP]] are rather hard to observe, but trained [[cardiologist]]s do try to discern these as signs of the state of the [[right atrium]].
The central venous pressure (CVP) lies approximately 5 cm above the middle of the [[right atrium]]. The  CVP is therefore estimated to be the JVP in cm plus 5 cm. Normally the CVP is 5-9 cm of H2O.


==Hepatojugular reflux==
The [[JVP]] and [[carotid pulse]] can be differentiated in several ways:
*'''Multiphasic''' - the [[JVP]] "beats" twice (in quick succession) in each[[cardiac cycle]].  In other words, there are two waves in the [[JVP]] for each contraction-relaxation cycle by the heart. The first beat represents the [[atrial contraction]] (termed ''a'' wave) and the second beat represents venous filling against a closed [[tricuspid valve]] (termed ''v''wave) and not the commonly mistaken '[[ventricular contraction]]'. The [[carotid artery]] has only one beat in the [[cardiac cycle]].
*'''Non-palpable''' - the [[JVP]] cannot be palpated.  If one feels a pulse in the neck, it is generally the [[common carotid artery]].
*'''Occlude''' - the [[JVP]] can be obliterated by occluding the [[internal jugular vein]] by lightly pressing the base of the neck.
*''' Varies with head-up-tilt (HUT)''' - the [[JVP]] varies with the angle of the neck.  If a person is standing their [[JVP]] appears to be lower on the [[neck]] (or may not be seen at all because it below the [[sternal angle]]).  The location of [[carotid pulse]] location does not vary with HUT.
*''' Varies with [[respiration]]''' - the [[JVP]] usually decreases with deep [[inspiration]].  Physiologically, this is a consequence of the [[Frank-Starling mechanism]] as [[inspiration]] decreases the thoracic pressure and increases blood movement into the heart ([[venous return]]), which a healthy heart moves into the [[pulmonary circulation]].
*'''Abdominal jugular reflux (AJR)''' (also hepatojugular reflux) - the [[JVP]] changes with abdominal pressure.  If the [[JVP]] is elevated 4 cm, it usually returns to its baseline level within 10 seconds.  If the [[JVP]] remains elevated for a longer period of time it suggests [[heart failure]].
 
 
{| class="wikitable"
|+
| colspan="3" rowspan="1" align="center" style="background: #4479BA; color: #FFFFFF " |'''Diffenetiating the jugular venous pulse from the carotid pulse'''
|+
| colspan="1" rowspan="1" align="center" style="background: #87CEEB; color: #FFFFFF" |'''Feature'''
| colspan="1" rowspan="1" align="center" style="background: #87CEEB; color: #FFFFFF " |'''Internal Jugular vein'''
| colspan="1" rowspan="1" align="center" style="background: #87CEEB; color: #FFFFFF " |'''Carotid artery'''
|+
| colspan="1" rowspan="1" |'''Appearance of [[pulse]]'''
| colspan="1" rowspan="1" |
* Biphasic: Two peaks and two troughs in each [[cardiac cycle]]
| colspan="1" rowspan="1" |
* Monophasic: A single brisk upstroke in [[cardiac systole]]
|-
| colspan="1" rowspan="1" |'''Palpability'''
| colspan="1" rowspan="1" |
* Not palpable (except in severe [[TR]])
| colspan="1" rowspan="1" |
* Palpable
|-
| colspan="1" rowspan="1" |'''Changes during [[inspiration]]'''
| colspan="1" rowspan="1" |
*Height of column falls
*Troughs become more prominent
| colspan="1" rowspan="1" |
* No [[respiratory]] change
|-
| colspan="1" rowspan="1" |'''Effects of pressure'''
| colspan="1" rowspan="1" |
*A gentle pressure at the base of the vein (clavicle) can obliterate the [[jugular venous pulsation]]
| colspan="1" rowspan="1" |
* Pressure cannot obliterate the [[carotid pulse]]
|-
|}
 
===[[Hepatojugular reflux]]===
{{main|Abdominojugular test}}
{{main|Abdominojugular test}}
''Hepatojugular reflux'', sometimes incorrectly referenced as a "reflex",<ref>{{cite journal | author = Aronson J | title = Hepatojugular reflux | journal = BMJ | volume = 318 | issue = 7192 | pages = 1172 | year = 1999 | id = PMID 10221938}} [http://bmj.bmjjournals.com/cgi/content/full/318/7192/1172 Free Full Text].</ref> is an expanded form of the JVP measurement. By pressing on the [[liver]] (''hepato-'') for 15-30 seconds, venous blood is advanced into the circulation. The JVP increases in a normal person, and distention should appear more pronounced. However, a slow decrease of the JVP after checking for hepatojugular reflux can indicate right ventricular failure.
''[[Hepatojugular reflux]]'', sometimes incorrectly referenced as a "reflex",<ref>{{cite journal | author = Aronson J | title = Hepatojugular reflux | journal = BMJ | volume = 318 | issue = 7192 | pages = 1172 | year = 1999 | id = PMID 10221938}} [http://bmj.bmjjournals.com/cgi/content/full/318/7192/1172 Free Full Text].</ref> is an expanded form of the [[JVP]] measurement. By pressing on the [[liver]] (''hepato-'') for 15-30 seconds, venous blood is advanced into the circulation. The [[JVP]] increases in a normal person, and distention should appear more pronounced. However, a slow decrease of the [[JVP]] after checking for [[hepatojugular reflux]] can indicate [[right ventricular failure]].


==Method==
==Video Instruction==
[[Image:Jvp-examination.jpg|left|thumb|Method to examine the JVP]]
This video contains a detailed explanation of what the [[JVP]] is, how it is measured, and what are the diagnostic considerations of [[JVP]], in terms of interpreting various [[JVP]] waveforms.
 
{{#ev:youtube|https://https://www.youtube.com/watch?v=O1MfBEmNj2s}}
 
==Causes of Elevated Jugular Venous Pressure==
 
*The most common causes of elevated [[JVP]] are: <ref name="Book1">{{cite book | last = Perloff | first = Joseph | title = Physical examination of the heart and circulation | publisher = People's Medical Pub. House | location = Shelton, CT | year = 2009 | isbn = 978-1-60795-023-3 }}</ref> <ref name="Book2">{{cite book | last = Bickley | first = Lynn | title = Bates' guide to physical examination and history taking | publisher = Wolters Kluwer | location = Philadelphia | year = 2017 | isbn = 9781469893419 }}</ref> <ref name="Book3">{{cite book | last = Zipes | first = Douglas | title = Braunwald's heart disease : a textbook of cardiovascular medicine | publisher = Elsevier/Saunders | location = Philadelphia, PA | year = 2019 | isbn = 978-0323463423 }}</ref>


A classical method for quantifying the JVP was described by Borst & Molhuysen in 1952.<ref>{{cite journal | author = Borst J, Molhuysen J | title = Exact determination of the central venous pressure by a simple clinical method. | journal = Lancet | volume = 2 | issue = 7 | pages = 304-9 | year = 1952 | id = PMID 14955978}}</ref> It has since been modified in various ways.
**[[Heart failure]]
**[[Constrictive pericarditis]] ([[JVP]] increases on [[inspiration]]- called [[Kussmaul's sign]])
**[[Cardiac tamponade]]
**[[Right ventricular myocardial infarction]]
**[[Fluid overload]] (eg, renal disease)
**[[Superior vena cava obstruction]] (no [[JVP]] pulsation)


The patient is positioned under 45°, and the filling level of the [[jugular vein]] determined. In healthy people, it is maximum several (3-4) centimetres above the [[sternum|sternal]] angle. Some doctors employ a ''venous arc'', an instrument to measure the JVP more accurately. A pen-light can aid in discerning the jugular filling level.
*'''To view a complete list of causes of elevated [[jugular venous pressure]], [[Jugular venous distention resident survival guide|click here]].'


===Visualization of the JVP===
== JVP waveform ==
The JVP is easiest to observe if one looks ''along'' the surface of the [[sternocleidomastoid muscle]], as it is easier to appreciate the movement relative the neck when looking from the side (as opposed to looking at the surface at a 90 degree angle).  Like judging the movement of an automobile from a distance, it is easier to see the movement of an automobile when it is crossing one's path at 90 degrees (i.e. moving left to right or right to left), as opposed to coming toward one.  Remember, tangential light is critical.


===Differentiation of the JVP from the carotid pulse===
The normal [[jugular venous pressure]] changes during different stages of [[cardiac cycles]] as a result of phasic pressure changes in the [[right atrium]].
[[Image:Jvp-vs-carotid.jpg|left|300px]]
It consists of two (and sometimes three) positive waves and two negative troughs.<ref name="Book1">{{cite book | last = Perloff | first = Joseph | title = Physical examination of the heart and circulation | publisher = People's Medical Pub. House | location = Shelton, CT | year = 2009 | isbn = 978-1-60795-023-3 }}</ref> <ref name="Book2">{{cite book | last = Bickley | first = Lynn | title = Bates' guide to physical examination and history taking | publisher = Wolters Kluwer | location = Philadelphia | year = 2017 | isbn = 9781469893419 }}</ref> <ref name="Book3">{{cite book | last = Zipes | first = Douglas | title = Braunwald's heart disease : a textbook of cardiovascular medicine | publisher = Elsevier/Saunders | location = Philadelphia, PA | year = 2019 | isbn = 978-0323463423 }}</ref>


[[Pulse]]s in the JVP are rather hard to observe, but trained cardiologists do try to discern these as signs of the state of the [[right atrium]].


The JVP and carotid pulse can be differentiated several ways:
*''' "a" wave:''' This presystolic wave is caused by venous distension due to the right atrial contraction. During [[inspiration]], increased [[venous return]] to the [[right atrium]] may accentuate this wave.  
*'''multiphasic''' - the JVP "beats" twice (in quick succession) in the [[cardiac cycle]].  In other words, there are two waves in the JVP for each contraction-relaxation cycle by the heart. The first beat represents that atrial contraction (termed ''a'') and second beat the VENOUS FILLING against a closed tricuspid valve (termed ''v'') and not the commonly mistaken 'ventricular contraction'. The carotid artery only has one beat in the cardiac cycle.
*''' "c" wave:''' This wave may sometimes be noted as a distinctive positive waveform. During early [[systole]], right ventricular [[isovolumetric contraction]] bulges the [[tricuspid valve]] into the [[right atrium]], leading to the appearance of the "c" wave. In addition, the increased [[carotid artery]] pressure during early [[systole]] may impact the adjacent [[jugular vein]].
*'''non-palpable''' - the JVP cannot be palpated. If one feels a pulse in the neck, it is generally the [[common carotid artery]].
*''' "X" descend:''' The X descend is caused by atrial relaxation and downward displacement of the [[tricuspid valve]] into the [[right ventricle]].  
*'''occludable''' - the JVP can be stopped by occluding the [[internal jugular vein]] by lightly pressing against the neck.
*''' "v" wave:''' This late-systolic wave is caused by the increasing volume of blood accumulating in the [[right atrium]] during the ventricular [[systole]] while the [[tricuspid valve]] is closed.
*'''varies with head-up-tilt (HUT)''' - the JVP varies with the angle of neck.  If a person is standing their JVP appears to be lower on the neck (or may not be seen at all because it below the [[sternal angle]]).  The carotid pulse's location does not vary with HUT.
*''' "Y" descend:''' The Y descend results from the opening of the [[tricuspid valve]] and rapid inflow of blood into the [[right ventricle]].  
*'''varies with respiration''' - the JVP usually descreases with deep inspiration.  Physiologically, this is a consequence of the [[Frank-Starling mechanism]] as inspiration decreases the thoracic pressure and increases blood movement into the heart (venous return), which a healthy heart moves into the [[pulmonary circulation]].
*'''abdominal jugular reflux (AJR)''' (also hepatojugular reflux) - the JVP changes with abdominal pressure.  If the JVP is elevated 4 cm, it usually returns to its baseline level within 10 seconds.  If the JVP remains elevated for a longer period of time it suggests [[heart failure]].


== JVP waveform ==
The jugular venous pulsation has a double waveform. The ‘a’ wave corresponds to atrial contraction and ends synchronously with the carotid artery pulse. The ‘c’ wave occurs when the ventricles begin to contract and is caused by bulging of the atrioventricular (AV) valves backwards towards the atria. The ‘v’ wave is seen when the tricuspid valve is closed, just before ventricular contraction – with and just after the carotid pulse. The ‘v’ wave represents the gradual build-up of blood in the atria while the AV valves are closed during ventricular contraction. The absence of ‘a’ waves is a feature of atrial fibrillation.


===Components of the JVP Waveform===
===Components of the JVP Waveform===
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<br clear="left"/>


===Abnormalities in the JVP Waveforms===
===Abnormal JVP waveforms===
 
*Various [[JVP]] waveform abnormalities are summarized as it follows: <ref name="Book1">{{cite book | last = Perloff | first = Joseph | title = Physical examination of the heart and circulation | publisher = People's Medical Pub. House | location = Shelton, CT | year = 2009 | isbn = 978-1-60795-023-3 }}</ref> <ref name="Book2">{{cite book | last = Bickley | first = Lynn | title = Bates' guide to physical examination and history taking | publisher = Wolters Kluwer | location = Philadelphia | year = 2017 | isbn = 9781469893419 }}</ref> <ref name="Book3">{{cite book | last = Zipes | first = Douglas | title = Braunwald's heart disease : a textbook of cardiovascular medicine | publisher = Elsevier/Saunders | location = Philadelphia, PA | year = 2019 | isbn = 978-0323463423 }}</ref>
 


{|style="width:80%; height:50px" border="1"
{| class="wikitable"
|-
|+
|Absence of a wave
| colspan="1" rowspan="1" align="center" style="background: #4479BA; color: #FFFFFF " |'''Abnormal [[JVP]] waveform'''
|[[Atrial fibrillation]]
| colspan="1" rowspan="1" align="center" style="background: #4479BA; color: #FFFFFF " |'''Associated Conditions'''
|+
| colspan="1" rowspan="1" |'''Absent "a" wave'''
| colspan="1" rowspan="1" |
*[[Atrial fibrillation]]
|-
| colspan="1" rowspan="1" |'''Large "a" wave'''
(caused by increased atrial contraction pressure)
| colspan="1" rowspan="1" |
*[[Tricuspid stenosis]]
*[[Pulmonary hypertension]]
*[[Pulmonic stenosis]]
*[[Right-sided heart failure]]
|-
| colspan="1" rowspan="1" |'''Cannon "a" wave'''
(caused by contraction of the [[right atrium]] against the closed [[tricuspid valve]])
| colspan="1" rowspan="1" |
*[[Complete heart block]] [[(Third-degree atrioventricular block)]]
*[[Premature atrial contractions]]
*[[Junctional rhythm]]
*[[Ventricular tachycardia]]
|-
| colspan="1" rowspan="1" |'''Decreased nadir of "x" descent'''
| colspan="1" rowspan="1" |
*[[Right ventricular dilation]]
|-
| colspan="1" rowspan="1" |'''Obliteration or reversed nadir of "x" descent'''
| colspan="1" rowspan="1" |
*[[Tricuspid regurgitation]]  
|-
|-
|Flutter of a wave
| colspan="1" rowspan="1" |'''Accentuated "x" descent'''
|[[Atrial flutter]]
| colspan="1" rowspan="1" |
*[[Constrictive pericarditis]]
|-
|-
|Prominent a waves
| colspan="1" rowspan="1" |'''Prominent "v" wave'''
|[[First-degree atrioventricular block]]
(caused by the backflow of blood to the [[right atrium]] during ventricular [[systole]])
| colspan="1" rowspan="1" |
*[[Tricuspid regurgitation]]
|-
|-
|Large a waves
| colspan="1" rowspan="1" |'''Slow "Y" descent'''
|[[Tricuspid stenosis]], Right atrial [[myxoma]], [[Pulmonary hypertension]], [[Pulmonic stenosis]]
(caused by slow emptying of the [[right atrium]])
| colspan="1" rowspan="1" |
*[[Tricuspid stenosis]]
*[[Right atrial myxoma]]
|-
|-
|Absent x descent
| colspan="1" rowspan="1" |'''Rapid, deep "Y" descent'''
|[[Tricuspid regurgitation]]
| colspan="1" rowspan="1" |
*Severe [[Tricuspid regurgitation]]
|-
|-
|Prominent x descent
| colspan="1" rowspan="1" |'''Sharp "Y" descent with a deep "Y" trough and a rapid ascent to the baseline''' (referred to as [[Friedreich's sign]])
|Conditions associated with large a waves
| colspan="1" rowspan="1" |
*[[Constrictive pericarditis]]
*Severe [[right-sided heart failure]]
|-
|-
|Slow y descent
| colspan="1" rowspan="1" |'''Slow "Y" descent'''
|[[Tricuspid stenosis]], [[Right atrial]] [[myxoma]]
(caused by obstruction to right [[ventricular filling]])
| colspan="1" rowspan="1" |
*[[Tricuspid stenosis]]
*[[Right atrial myxoma]]
|-
|-
|Rapid y descent
| colspan="1" rowspan="1" |'''Absent "Y" descent'''
|[[Constrictive pericarditis]], severe [[Right heart failure]], [[Tricuspid regurgitation]], [[Atrial septal defect]]
| colspan="1" rowspan="1" |
*[[Cardiac tamponade]]
|-
|-
|Absent y descent
|}<br />
|[[Cardiac tamponade]]
|}


==References==
==References==
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Mitra Chitsazan, M.D.[2] Mandana Chitsazan, M.D. [3]

Synonyms and keywords: Jugular venous distention; elevated JVP; JVD; elevated neck veins; distended neck veins

Overview

The jugular venous pressure (JVP, sometimes referred to as jugular venous pulse) is the indirectly observed pressure over the venous system. It can be useful in the differentiation of various forms of heart and lung disease.

Classically three upward deflections (waves) and two downward deflections (toughs) have been described. The upward deflections are the "a" (atrial filling), "c" (ventricular contraction and resulting bulging of tricuspid into the right atrium during isovolumic systole), and "v" (atrial venous filling) waves, and the downward deflections are the "x"(when tricuspid opens and ventricular filling occurs) and the "y" descents (filling of ventricle after tricuspid opening).

The interpretation of JVP findings can be challenging and is becoming a lost art, as much of the subtle information previously obtained by careful observation of the JVP can now be gained easily with echocardiography and/or EKG. Certain waveform abnormalities include "Cannon a-waves", which result when the atrium contracts against a closed tricuspid valve, due to complete heart block (3rd-degree heart block), or even in ventricular tachycardia. Another abnormality, "c-v waves", can be a sign of tricuspid regurgitation.

An elevated JVP is the classic sign of venous hypertension (e.g. right-sided heart failure). The paradoxical increase of the JVP with inspiration (instead of the expected decrease) is referred to as the Kussmaul sign and indicates impaired filling of the right ventricle. The differential diagnosis of Kussmaul's sign includes constrictive pericarditis, restrictive cardiomyopathy, pericardial effusion, and severe right-sided heart failure.

Anatomy

  • Right and left internal jugular veins (IJVs):
    • Paired neck veins draining the head and neck.
    • Originate from the dural venous sinuses and leave the skull via the jugular foramen, then descend through the neck alongside and lateral to the internal carotid arteries.
    • Then join the subclavian veins (at the base of the neck) to form the brachiocephalic vein.
    • The IJVs lies deep to the skin and soft tissues; therefore, they are not directly visible and identification only is possible via visualization of pulsations transmitted to the surface of the neck.
    • Additionally, these blood vessels are under much lower pressure than the adjacent, pulsating carotid artery. It, therefore, takes a sharp eye to identify the relatively weak, transmitted venous impulses.

Technique

Method to examine the JVP
  • A classical method for quantifying the JVP was described by Borst & Molhuysen in 1952.[1] It has since been modified in various ways. [2] [3] [4]
  • The patient is positioned under 45°, and the filling level of the jugular vein is determined. In healthy people, it is a maximum of several (3-4) centimeters above the sternal angle. Some physicians employ a venous arc, an instrument to measure the JVP more accurately. A pen-light can aid in discerning the jugular filling level.

Visualization of the JVP

The JVP is easiest to observe if one looks along the surface of the sternocleidomastoid muscle, as it is easier to appreciate the movement relative to the neck when looking from the side (as opposed to looking at the surface at a 90-degree angle). Like judging the movement of an automobile from a distance, it is easier to see the movement of an automobile when it is crossing one's path at 90 degrees (i.e. moving left to right or right to left), as opposed to coming toward one. Remember, tangential light is critical.

A few things to remember:

  • Think anatomically
    • The right internal jugular vein (IJV) runs between the two heads (sternal and clavicular) of the sternocleidomastoid muscle (SCM) and up in front of the ear.
    • This muscle can be identified by asking the patient to turn their head to the left and into your hand while you provide resistance to the movement.
    • The two heads form the sides of a small triangle, with the clavicle making up the bottom edge. You should be able to feel a shallow defect formed by the borders of these landmarks.
    • Note, you are trying to identify impulses originating from the IJV and transmitted to the overlying skin in this area. You can't actually see the IJV.
    • The external jugular vein (EJV) runs in an oblique direction across the sternocleidomastoid muscle and, in contrast to the IJV, can usually be directly visualized.
    • If the EJV is not readily apparent, have the patient look to the left and do a Valsalva manuver. This usually makes it quite obvious.
    • EJV distention is not always a reliable indicator of elevated CVP as valves, designed to prevent the retrograde flow of blood, can exist within this vessel causing it to appear engorged even when CVP is normal. It also makes several turns before connecting with the central venous system and is thus not in a direct line with the right atrium.
  • Take your time.
    • Look at the area in question for several minutes while the patient's head is turned to the left.
    • The carotid artery is adjacent to the IJV, lying just medial to it.
    • If you are unsure whether a pulsation is caused by the carotid artery or the IJV, place your hand on the patient's radial artery and use this as a reference.
    • The carotid impulse coincides with the palpated radial artery pulsation and is characterized by a single upstroke timed with systole.
    • The venous impulse (at least when the patient is in sinus rhythm and there is no tricuspid regurgitation) has three components, each associated with a, c, and v waves. When these are transmitted to the skin, they create a series of flickers that are visible diffusely within the overlying skin.
    • In contrast, the carotid artery causes a single up and down pulsation.
    • Furthermore, the carotid artery is palpable, while the IJV is not palpable and can, in fact, be obliterated by applying pressure in the area where it emerges above the clavicle.
  • Search along the entire projected course of the IJV as the top of the pressure wave (which is the point that you are trying to identify) may be higher than where you are looking.
    • In fact, if the patient's CVP is markedly elevated, you may not be able to identify the top of the wave unless they are positioned with their trunk elevated at 45 degrees or more (else there will be no identifiable "top" of the column as the entire IJV will be engorged).
    • After you have found the top of the wave, see what effect sitting straight up and lying down flat has on the height of the column. Sitting should cause it to appear at a lower point in the neck while lying has the opposite effect. Realize that these maneuvers do not change the actual value of the central venous pressure. They simply alter the position of the top of the pulsations in relation to other structures in the neck and chest.
  • Shine a penlight tangentially across the neck. This sometimes helps to accentuate the pulsations.
  • If you are still uncertain, apply gentle pressure to the right upper quadrant of the abdomen for 5 to 10 seconds.
    • This elicits Hepatojugular reflux which, in pathological states, will cause blood that has pooled in the liver to flow in a retrograde fashion and fill out the IJV, making the transmitted pulsations more apparent.
    • Make sure that you are looking in the right area when you push as the best time to detect any change in the height of this column of blood is immediately after you apply hepatic pressure.
  • Once you identify JVD, try to estimate how high in cm the top of the column is above the Angle of Louis.
    • The angle is the site of the joint that connects the manubrium with the body of the sternum. First identify the suprasternal notch, a concavity at the top of the manubrium.
    • Then walk your fingers downward until you detect a subtle change in the angle of the bone, which is approximately 4 to 5 cm below the notch.
    • This is roughly at the level of the 2nd intercostal space.
    • The vertical distance from the top of the column to this angle is added to 5cm, the rough vertical distance from the angle to the right atrium with the patient lying at a 45-degree angle.
    • The sum is an estimate of the CVP. Normal CVP is 7-9 cm.

The CVP vs the JVP

The central venous pressure (CVP) lies approximately 5 cm above the middle of the right atrium. The CVP is therefore estimated to be the JVP in cm plus 5 cm. Normally, the CVP is 5-9 cm of H2O.

(Images courtesy of Charlie Goldberg, M.D., UCSD School of Medicine and VA Medical Center, San Diego, California)


Differentiation of the JVP from the carotid pulse

Pulses in the JVP are rather hard to observe, but trained cardiologists do try to discern these as signs of the state of the right atrium.

The JVP and carotid pulse can be differentiated in several ways:

  • Multiphasic - the JVP "beats" twice (in quick succession) in eachcardiac cycle. In other words, there are two waves in the JVP for each contraction-relaxation cycle by the heart. The first beat represents the atrial contraction (termed a wave) and the second beat represents venous filling against a closed tricuspid valve (termed vwave) and not the commonly mistaken 'ventricular contraction'. The carotid artery has only one beat in the cardiac cycle.
  • Non-palpable - the JVP cannot be palpated. If one feels a pulse in the neck, it is generally the common carotid artery.
  • Occlude - the JVP can be obliterated by occluding the internal jugular vein by lightly pressing the base of the neck.
  • Varies with head-up-tilt (HUT) - the JVP varies with the angle of the neck. If a person is standing their JVP appears to be lower on the neck (or may not be seen at all because it below the sternal angle). The location of carotid pulse location does not vary with HUT.
  • Varies with respiration - the JVP usually decreases with deep inspiration. Physiologically, this is a consequence of the Frank-Starling mechanism as inspiration decreases the thoracic pressure and increases blood movement into the heart (venous return), which a healthy heart moves into the pulmonary circulation.
  • Abdominal jugular reflux (AJR) (also hepatojugular reflux) - the JVP changes with abdominal pressure. If the JVP is elevated 4 cm, it usually returns to its baseline level within 10 seconds. If the JVP remains elevated for a longer period of time it suggests heart failure.


Diffenetiating the jugular venous pulse from the carotid pulse
Feature Internal Jugular vein Carotid artery
Appearance of pulse
Palpability
  • Not palpable (except in severe TR)
  • Palpable
Changes during inspiration
  • Height of column falls
  • Troughs become more prominent
Effects of pressure

Hepatojugular reflux

Hepatojugular reflux, sometimes incorrectly referenced as a "reflex",[5] is an expanded form of the JVP measurement. By pressing on the liver (hepato-) for 15-30 seconds, venous blood is advanced into the circulation. The JVP increases in a normal person, and distention should appear more pronounced. However, a slow decrease of the JVP after checking for hepatojugular reflux can indicate right ventricular failure.

Video Instruction

This video contains a detailed explanation of what the JVP is, how it is measured, and what are the diagnostic considerations of JVP, in terms of interpreting various JVP waveforms.

{{#ev:youtube|https://https://www.youtube.com/watch?v=O1MfBEmNj2s}}

Causes of Elevated Jugular Venous Pressure

JVP waveform

The normal jugular venous pressure changes during different stages of cardiac cycles as a result of phasic pressure changes in the right atrium. It consists of two (and sometimes three) positive waves and two negative troughs.[2] [3] [4]



Components of the JVP Waveform

a = atrial contraction, occurs just before 1st heart sound and carotid pulse x = atrial relaxation c = bulging of tricuspid valve during isovolumetric contraction; x 1 = occurs during ventricular contraction pulling down the tricuspid valve “descent of the base”; v = occurs during venous filling of the atrium with a closed tricuspid valve\; y = opening of tricuspid valve and right atrium emptying


Abnormal JVP waveforms

  • Various JVP waveform abnormalities are summarized as it follows: [2] [3] [4]


Abnormal JVP waveform Associated Conditions
Absent "a" wave
Large "a" wave

(caused by increased atrial contraction pressure)

Cannon "a" wave

(caused by contraction of the right atrium against the closed tricuspid valve)

Decreased nadir of "x" descent
Obliteration or reversed nadir of "x" descent
Accentuated "x" descent
Prominent "v" wave

(caused by the backflow of blood to the right atrium during ventricular systole)

Slow "Y" descent

(caused by slow emptying of the right atrium)

Rapid, deep "Y" descent
Sharp "Y" descent with a deep "Y" trough and a rapid ascent to the baseline (referred to as Friedreich's sign)
Slow "Y" descent

(caused by obstruction to right ventricular filling)

Absent "Y" descent


References

  1. Borst J, Molhuysen J (1952). "Exact determination of the central venous pressure by a simple clinical method". Lancet. 2 (7): 304–9. PMID 14955978.
  2. 2.0 2.1 2.2 2.3 Perloff, Joseph (2009). Physical examination of the heart and circulation. Shelton, CT: People's Medical Pub. House. ISBN 978-1-60795-023-3.
  3. 3.0 3.1 3.2 3.3 Bickley, Lynn (2017). Bates' guide to physical examination and history taking. Philadelphia: Wolters Kluwer. ISBN 9781469893419.
  4. 4.0 4.1 4.2 4.3 Zipes, Douglas (2019). Braunwald's heart disease : a textbook of cardiovascular medicine. Philadelphia, PA: Elsevier/Saunders. ISBN 978-0323463423.
  5. Aronson J (1999). "Hepatojugular reflux". BMJ. 318 (7192): 1172. PMID 10221938. Free Full Text.