Examination of the jugular venous pulse

INTRODUCTION — When properly performed, the careful examination of jugular venous waveforms in the neck provides the clinician with a reasonable estimate of central venous pressures (CVP), and it also imparts prognostic information in patients with heart failure (HF) [1]. (See 'Evidence on utility and limitations' below.)

Experienced clinicians contend that bedside evaluation of the CVP remains nearly universally feasible, clinically meaningful, immediately available, and readily repeatable. However, this view is not shared by some other clinicians and there is a trend to devote less attention to the bedside evaluation of physical signs as the technology for diagnostic testing has advanced [2,3].

This topic will discuss the examination of the jugular venous pulse. Other components of the cardiovascular examination including inspection of precordial pulsation, examination of the arterial pulse, auscultation of heart sounds, and auscultation of cardiac murmurs are discussed separately. (See "Examination of the precordial pulsation" and "Examination of the arterial pulse" and "Auscultation of heart sounds" and "Auscultation of cardiac murmurs in adults" and "Physiologic and pharmacologic maneuvers in the differential diagnosis of heart murmurs and sounds" and "Common causes of cardiac murmurs in infants and children" and "Approach to the infant or child with a cardiac murmur".)

ANATOMIC CONSIDERATIONS — Inspection of the jugular veins enables visible evaluation of central venous pressures which reflect volume in the central venous reservoir.

The central veins are thin walled, distensible reservoirs and conduits of blood in continuity with the right atrium. The volume in this venous reservoir is determined by the inflow from venous return from the upper and lower parts of the body and the outflow through the right atrium to the right ventricle (RV).

The visual appreciation of the extent of jugular venous distention and the characteristics of the pressure waves are dependent on clear understanding and appreciation of the anatomic relations of the vein to fixed anatomic structures in the neck (figure 1). The internal jugular vein (IJV) is formed by the joining of the inferior petrosal sinus and the sigmoid sinus at the base of the brain and exits the skull via the jugular foramen. The IJV then descends vertically within the carotid sheath, lateral to the internal carotid artery and common carotid artery and deep to the sternocleidomastoid. The IJV joins the subclavian vein to form the brachiocephalic vein at the base of the neck (figure 1).

The external jugular vein (EJV) is formed by the posterior auricular vein and retromandibular vein (posterior branch) posterior to the angle of the mandible (figure 1). After formation, the EJV descends down the neck within the superficial fascia running obliquely across the sternocleidomastoid muscle and ending by draining into the subclavian vein.

Although there are valves between the superior vena cava and both internal and external jugular veins, elevated venous pressure can be transmitted through the venous valves.

USE — Examination of the jugular venous pulse is a standard component of the cardiovascular examination, although its utility varies among examiners and clinical settings.

Indications — Indications for jugular venous pulse examination include the following:

●The most common indication is to use jugular venous pressure (JVP) to estimate whether right atrial pressure (RAP) is high or normal and to assess how RAP changes over time, including its response to medical therapy. (See 'To estimate right atrial pressure' below.)

RAP estimation is an important component of the evaluation of HF. Since left HF is a major cause of elevated right heart pressures, estimation of RAP using the JVP can aid in initial diagnosis of HF as well as in detection of HF exacerbation. (See 'To identify and assess heart failure' below.)

●Evaluation of jugular venous pulse is helpful in the diagnosis and evaluation of a variety of additional cardiovascular disorders including superior vena cava obstruction, tricuspid valve disease, and pericardial disease. (See "Malignancy-related superior vena cava syndrome" and "Examination of jugular venous waveforms".)

Evidence on utility and limitations — The available evidence on use of the jugular venous pulse examination is difficult to summarize given differences in examiner training and technique (including use of the internal jugular vein [IJV] or external jugular vein [EJV]), patient populations, and comparators (eg, noninvasively or invasively measured central venous pressure [CVP] or clinical outcomes) [4].

To estimate right atrial pressure — The utility of examination of the jugular venous pulse to estimate RAP varies among clinical settings as noted in a review that included 10 studies published over a span of 40 years [4]:

●The frequency of an interpretable JVP varied widely depending upon clinical setting and examiner experience. In some studies, the IJV was commonly not visible, while in others the IJV was generally interpretable.

●Some studies have found that clinical estimates of JVP tend to underestimate CVP [5]. This discrepancy may be caused by underestimation of the distance between the sternal angle and the central right atrium, traditionally assumed to be 5 cm, but imaging studies have shown that the actual distance varies with patient position and among patients, as described below. (See 'General principles' below.)

●The accuracy of JVP (by IJV or EJV) for detection of elevated CVP varies widely among clinical settings and observers (eg, sensitivity JVP by IJV for elevated CVP ranged from 14 to 86 percent in one review [4]). As examples:

•In the ESCAPE trial, investigators skilled in the care of patients with advanced HF were usually able to determine if the RAP was <8 mmHg (likelihood ratio 16.6) in such patients, and the area under the survival curve for their estimates of RAP >12 mmHg was 0.74 [6].

•In a single-center observational study, examination-based accuracy of the RAP was greater for staff cardiologists compared with trainees (82 versus 67 percent) [7], emphasizing the value of training and experience in estimating the JVP.

The specificity of JVP for elevated RAP likely also varies with clinical setting. When an elevated JVP is observed, causes of elevated RAP as well as other causes (eg, superior vena cava obstruction) should be considered. (See 'Causes of elevated jugular venous pressure' below.)

To identify and assess heart failure — Many of the symptoms experienced by patients with HF are due to an elevation of the filling pressures of either the right or left ventricle (LV; ie, the RAP or LV end-diastolic pressure [LVEDP], respectively). The above cited review found that an elevated JVP was of value in diagnosing HF across clinical settings [4]. In a primary care setting, an elevated JVP had diagnostic value for detection of LV systolic dysfunction independent of other clinical variables (odds ratio 15.1, 4.6 to 49.3) [8]. The JVP is the most important marker of the intravascular volume status in a patient with HF [9]. Indeed, in the ESCAPE trial of patients with HF, the only two findings from the history and physical examination which were associated with an elevated pulmonary capillary wedge pressure (PCWP) were the presence of orthopnea or an elevated JVP [6].

The JVP is an estimate of the RAP and is not a direct measure of the LV filling pressures (LVEDP). The left atrial pressure is generally a measure of the LVEDP and is estimated on right heart catheterization by measurement of the PCWP. However, in patients with chronic HF with reduced ejection fraction (HFrEF), the RAP and PCWP are often related; specifically, both are either elevated or not elevated ("concordant") in 70 to 75 percent of patients with HFrEF [6,9]. One study suggested a similar concordance rate in patients with HF with preserved ejection fraction [10]. In the remaining 25 to 30 percent of patients, the RAP will not reflect the PCWP (called "discordance"), either being low when the PCWP is high or being high when the PCWP is low [11]. In patients with a discordance of the RAP and PCWP, assessment of the LV filling pressures by an estimate of the JVP will be inaccurate.

To assess risk of progression of ALVSD to heart failure — The presence of an elevated JVP has prognostic significance among asymptomatic patients with systolic LV dysfunction (ALVSD) and patients with current or prior symptomatic HFrEF. In a post-hoc analysis of data from 4102 SOLVD participants with asymptomatic or mildly symptomatic LV systolic dysfunction, presence of elevated JVP and presence of a third heart sound were independent predictors of an increased risk of progression to symptomatic HF [12] during the 34 months mean follow-up.

To assess prognosis in patients with heart failure — A retrospective analysis of 2569 SOLVD participants with HFrEF (or history of HF) found that an elevated JVP was associated with an increased risk of hospitalization for HF, death or hospitalization for HF, and death from pump failure during mean 32 months follow-up even when adjusting for other markers of disease severity including the LV ejection fraction [1]. Among patients discharged from the hospital for decompensated HF, those who were free of congestion (which included an absence of elevated JVP) at their first follow-up visit had a reduced risk of subsequent adverse outcomes [13]. In a larger analysis from the EVEREST trial, subjects with evidence of clinical congestion (which could include elevated JVP) were at subsequent increased risk of death after a median follow-up of 9.9 months [14].

HOW TO EXAMINE THE JUGULAR VENOUS PULSE

Approach to examination — The examination of the jugular venous pulse involves observing the patient’s jugular veins at varying degrees of head and upper body elevation and with maneuvers to estimate right atrial pressure (RAP) and determine if there are abnormalities in the jugular venous wave form. (See 'Estimating right atrial pressure' below and "Examination of jugular venous waveforms".)

Which jugular vein to examine — The right internal jugular vein (IJV) pulse is generally preferred for assessing right heart hemodynamics since the right IJV and right brachiocephalic vein are in a direct line with the superior vena cava.

If the right IJV pulsation is not visible, then the left IJV pulsation may generally be assessed. The left IJV pulse may be less reliable for estimating RAP than the right IJV because the left brachiocephalic vein crosses the mediastinum and may be partially obstructed by mediastinal structures including the great vessels. Partial compression of the left brachiocephalic vein is usually relieved during modest inspiration as the diaphragm and the aorta descend and the pressure in the two IJVs becomes equal. However, partial obstruction of the left brachiocephalic vein from compression by the aorta may persist, particularly in older adult patients, impairing transmission of RAP to the left IJV; this is the most common cause of unequal pressures between right and left IJVs.

We suggest examining the right external jugular vein (EJV) when the IJVs cannot be adequately visualized [15-17]. The EJV is more superficial, can sometimes be more easily assessed than the IJV, and can provide accurate results [15,18,19]. However, the EJVs are not in a direct line with the superior vena cava and connect with it after negotiating two almost 90 degree angles [20] (see "Cardiac catheterization techniques: Normal hemodynamics"). The external jugular venous bulb is a site for thrombus formation, which can cause partial obstruction of the EJVs. It is therefore important to see a respirophasic component in the wave form in the EJV (rather than a static column) when using it to estimate the central venous pressure (CVP), for if there is a thrombus or obstructing valve or a kinking, then the height of the column will no longer reflect the CVP. In some patients, the only EJV visible is in the center of the neck.

Technique — Evaluation of jugular venous pulsations is perhaps one of the most challenging physical diagnostic techniques to master. Suggestions for training include demonstration by a clinician skilled in this technique and examination of a broad spectrum of patients with normal and elevated jugular venous pressure (JVP). Once the basic principles of this examination are understood and practiced in a repetitive manner, the confidence in assessment of the jugular venous pulse improves significantly. (See 'To estimate right atrial pressure' above.)

General approach — Attention to a few basic points is essential for proper examination of the IJV (or EJV) [21] (movie 1):

●The examiner generally stands on the right side of the bed as examination of the right side of the neck is generally preferred. (See 'Which jugular vein to examine' above.)

●The patient lies supine upon an examination table or bed that breaks in the middle at the hips to allow elevation and lowering of the entire upper body from head to thorax as a unit.

●The patient’s neck should be extended with sternocleidomastoid muscles relaxed; this is generally achieved with either a thin pillow or no pillow underneath the patient’s head.

●Turn the head away (to the left if examining from the right) slightly (eg, 30 degrees from facing forward) and tip the head and jaw slightly up. This positioning may be guided by gentle pressure of the examiner’s fingers on the patient’s jaw to lift the jaw and neck upwards.

●A helpful technique to improve visibility of the venous pulsations is to shine a flashlight tangentially to the skin over the mid portion of the neck.

●The upper part of the examination table or bed is raised to elevate the patient’s head, neck, and thorax together as a unit with a bend at the hips. The degree of upper body elevation is the angle (0 to 90 degrees) at which the venous meniscus is best appreciated along the neck. The optimal angle depends upon the level of the JVP. Thus, it may be necessary to move the examination table or bed through various angles until the pulsation is visible.

•Low venous pressures are best seen in or near a supine position (0 degree angle), while high JVPs are seen best with the patient sitting upright (90 degrees).

•Since it is important to detect a high JVP, we suggest always inspecting the neck with the patient sitting upright at some point during the examination. If the JVP is seen above the clavicle when the upper body is elevated to 90 degrees, the venous pressures are likely elevated [22]. A high JVP may be missed in the supine position as the pulsation may be hidden high up (superiorly) in the neck. In patients with a very high JVP, the pulsation can cause the lower part of the ear lobe to pulsate.

Estimating JVP in patients with obesity is particularly challenging since the layer of fat in the neck obscures jugular venous pulsations. When the JVP is markedly elevated, ear lobe pulsations (waggle) can be appreciated in some patients due to the proximity of the posterior auricular vein, a branch of the external jugular vein, to the bottom of the ear (figure 1) [23].

●Use of maneuvers:

•Neck veins that collapse during deep inspiration or with vigorous sniff point to a normal JVP.

•If the JVP appears low in the supine position, an abdominojugular test is performed. (See 'Abdominojugular test' below.)

•Assess how inspiration impacts the JVP. Normally, the JVP will decrease with inspiration. In some patients, the JVP will not decrease or may even increase with inspiration, a finding known as "Kussmaul sign." (See 'Respirophasic changes (Kussmaul sign)' below.)

Additional considerations for the EJV — The EJV runs over the sternocleidomastoid muscle and is thus generally easier to visualize than the IJV [15].

The general examination of the EJV is as described above. (See 'General approach' above.)

The EJV can be identified by placing the forefinger just above the clavicle and pressing lightly. This will occlude the vein, which will then distend as blood continues to enter from the cerebral circulation. At this point, the vein should be occluded superiorly (to prevent distention by continued blood flow) and the occlusion at the clavicle released. The venous pressure can now be measured, since it will be approximately equal to the vertical distance between the upper level of the fluid column within the vein and the level of the right atrium (generally estimated as being 5 to 6 cm posterior to the sternal angle of Louis).

If the vein is distended throughout its length, the patient's trunk should be elevated to 45 or even 90 degrees until an upper level can be seen. In a patient with a markedly increased venous pressure due to RV failure, the EJV may remain distended even when the patient is upright.

There are some limitations to the use of this technique:

●The EJV may not become visible when it is occluded at the clavicle, particularly in those patients with a thick neck. If this occurs, it should not be assumed that the venous pressure is very low. Rather, the venous pressure should be measured in some other way, such as estimation of the level of pulsations in the IJV or directly by insertion of a catheter into the right atrium.

●A much less common problem is kinking or obstruction (eg, by valves or compression) of the EJV at the base of the neck. In this setting, there is an increase in the external JVP that does not reflect a similar change in RAP. This possibility should be suspected if the other jugular vein is visible and not distended or if an elevated venous pressure is found in a patient with no evidence or history of cardiac, pulmonary, or renal disease. Examination of internal jugular venous pulsations is warranted in such patients.

A study comparing blinded EJV examination with indwelling catheter measurements of CVP in 35 patients found good reliability for identifying low (≤5 cm water) and high (≥10 cm water) CVP, with areas under the curve of 0.95 and 0.97 for attending physicians and 0.78 and 0.81 for novice examiners [15].

Troubleshooting — The two most common problems encountered when estimating the JVP are difficulty distinguishing venous and arterial pulsations and failing to identify the venous pulse, as discussed below.

Distinguishing venous and arterial pulsations — Differentiating the venous and arterial pulse can be difficult as both may occur in the same region of the neck. Some distinguishing features are helpful (table 1) (see "Examination of the arterial pulse"):

●By inspection:

•The venous pulse is recognized by its double undulation (a and v waves), frequently associated with relatively sharper inward movement (the x descent following the a wave and y descent following the v wave). A c wave on the downstroke of the x descent is also commonly identified on venous pressure tracings but is generally not discerned by physical examination.

The carotid artery has one brisk upstroke. The dominant movement in the venous pulse is always inward (the x descent) [24]. The double undulation character of the venous pulse is lost during atrial fibrillation due to the absence of an a wave associated with atrial systole. The venous pulse still can be recognized from its dominant inward movement.

•The carotid pulse is more easily visible medially and higher in the neck, generally in the submandibular region. It is characterized by a single, sharp outward movement.

●By palpation: The arterial pulse is more easily palpable than the venous pulse. Occasionally the venous pulse also becomes palpable when there is significant venous volume change with severe tricuspid regurgitation.

●The venous pulse can be manipulated by changing the venous pressure.

•A key technique is to compress the neck below the pulsation. Gentle to moderate compression at the root of the neck obliterates the venous pulse in the neck, while the arterial pulsation remains visible. This maneuver is particularly useful for separating a very prominent venous pulsation from the carotid artery pulsation. Compression at the root of the neck may cause distention of the veins distal to the obstruction by impeding flow of blood to the heart, although pulsation will be absent due to blockade of the retrograde transmission of the pulse wave from the right atrium. When venous compression is released, jugular venous pulsations are often exaggerated for one or two cycles while the carotid artery pulsation is unchanged.

•Pressure in the neck veins generally decreases appreciably during inspiration, giving the impression of "inspiratory collapse." By contrast, the arterial pulse amplitude does not change significantly during inspiration.

•The amplitude and location of the venous pulsation in the neck can be reduced by raising the level of the head and trunk above the level of the right atrium (eg, sitting or standing), which reduces venous return and pressure, or increased by enhancing the venous return to the right side of the heart by raising the legs or compressing the abdomen. (See 'Abdominojugular test' below.)

Venous pulse not identified — If the venous pulse is not readily identified at 30 degrees, a range of upper body elevations are assessed. If you are having trouble seeing any venous pulsation in the neck, reattempt in the supine (in case RAP is very low) and upright (in case RAP is very high) positions. Apply pressure to the right upper quadrant to see if that unmasks a wave form. Look at the neck both during inspiration and expiration to see if a pulsation changes. Confirm that you have looked at both sides of the neck and in the midline of the neck. Despite all of these maneuvers, if you still cannot see a venous wave form, then document that observation; in our experience, there are a minority of patients where the jugular venous pulse is simply not visible, undoubtedly due to anatomic variation or body habitus. In such cases, some have advocated looking at the collapse of the peripheral veins on the dorsum of the hand (or antecubital fossa) while the arm is slowly elevated passively from a dependent position. The CVP is considered elevated if peripheral venous collapse occurs above the level of the sternal angle [25]. Alternatively, ultrasound assessment of the inferior vena cava size and degree of respiratory collapse (see "Echocardiographic assessment of the right heart", section on 'RA pressure') or right IJV meniscus [26-28] can be used to estimate the RAP.

●If the jugular venous pulse is not easily recognized, the venous pressure may be either very high or very low. The patient should be examined in supine position (in case RAP is very low) and upright position (in case RAP is very high):

•If the jugular venous pulse is seen above the clavicle when the upper body is elevated to 90 degrees (patient sitting completely upright), the venous pressures are likely elevated [22].

•If the jugular veins are distended but pulsations are not seen, superior vena cava obstruction should be suspected. (See 'Causes of elevated jugular venous pressure' below.)

•If venous pulsations are best seen with the upper body in a nearly flat horizontal (0 degree) position, the venous pressure is normal or low. With normal venous pressures, the venous pulsation is usually visible in the neck when the upper body is nearly flat. Low venous pressure should be suspected if the neck veins collapse with the upper body in a nearly flat horizontal position.

●If the JVP remains difficult to assess (eg, due to the patient’s body habitus), one or more of the following alternative noninvasive approaches may be helpful:

•The finding of a pulsating earlobe may provide a strong clue that the CVPs are significantly elevated. This occurs because the posterior auricular vein runs close to the ear lobe (figure 1).

•Peripheral venous collapse on the dorsum of the hand (or antecubital fossa) can be used in lieu of JVP. The arm is slowly elevated passively from a dependent position. The CVP is considered elevated if peripheral venous collapse occurs above the level of the sternal angle [25].

•Ultrasound estimation of CVP:

-CVP is commonly estimated by assessment of inferior vena cava size and degree of respiratory collapse as a component of an echocardiographic evaluation, as discussed separately. (See "Echocardiographic assessment of the right heart", section on 'RA pressure'.)

-The CVP can also be evaluated by ultrasound assessment of the right IJV meniscus [26-28].

Estimating right atrial pressure — Examination of the jugular venous pulse is one of the methods used to assess volume status (movie 1). The normal venous pressure is 1 to 11 cm of water (or blood) or 1 to 8 mmHg (1.36 cm of water is equal to 1.0 mmHg). Thus, a low value is consistent with but not diagnostic of volume depletion since it may be normal. Another important use is to distinguish the different causes of generalized edema: The venous pressure is elevated in HF and renal failure (due to volume overload) but is usually normal in cirrhosis (unless there is tense ascites) or nephrotic syndrome. (See "Clinical manifestations and evaluation of edema in adults".)

General principles — The RAP is estimated by adding the height of the jugular venous column above the sternal angle (JVP height) to the vertical distance from the mid-right atrium to the sternal angle. We estimate RAP by adding 5 cm to the vertical height in cm of the JVP column above the sternal angle:

Of note, 1 cm water = 0.74 mmHg.

Traditionally, it was assumed that the right atrium is located approximately 5 cm below the sternal angle. However, using 5 cm for all patients at all levels of elevation may lead to underestimation of RAP [5].

Alternatively, some have suggested using an estimated vertical distance from the right atrium to sternal angle of 5 cm when the patient is in a flat horizontal position (0 degree), 8 cm when the upper body is elevated 30 degrees, and 10 cm when the upper body is elevated 45 degrees or more [24]. This approach is based upon a study of the vertical distance between the sternal angle and the level of the right atrium by computed tomography (CT) scan in 160 patients [29].

Body habitus may also influence the height from the sternal angle of Louis to the right atrium. In a cross-sectional study with 52 patients who underwent CT, a positive correlation was found between patients' weight or body mass index and the distance from the angle of Louis to the right atrium [30]. Thus, in patients with body mass index >35 kg/m² (or body surface area >2.5 m²), a jugular venous column height at the clavicle is likely to indicate significantly elevated JVP.

However, these limitations are generally not critical since the main value of JVP examination comes from determining whether the RAP is low or high and how it changes over time including response to medical therapy [31]. We therefore continue to suggest generally adding 5 cm to the vertical height of the JVP above the sternal angle when estimating RAP.

Causes of elevated jugular venous pressure — Elevated JVP generally reflects increased RAP but may also be caused by superior vena cava obstruction or increased intrathoracic pressure. Abnormal findings on jugular venous examination should always be interpreted in conjunction with other findings to establish the diagnosis.

Causes of increased RAP include restriction of right atrial and RV filling (eg, cor pulmonale, pulmonary hypertension, constrictive pericarditis), RV failure (eg, cardiomyopathy), fluid overload due to renal disease (eg, poststreptococcal glomerulonephritis), tricuspid valve incompetence, and tricuspid valve stenosis or obstruction.

The character of the venous pulse and associated physical findings may help distinguish elevated RAP from venous obstruction. When elevated venous pressure is caused by elevated RAP, venous pulsations persist. By contrast, bilateral elevation of the mean JVP in the absence of venous pulsation should raise suspicion of superior vena cava obstruction. Additional findings associated with superior vena cava obstruction include prominent distended veins in the upper extremities and in the upper torso with lateral thoracic veins draining caudally to the veins below the umbilicus.

It should be recognized that the JVP is also elevated by an increase in intrathoracic pressures. This effect is seen in the setting of positive pressure ventilation, a large pleural effusion, or pneumothorax [32].

Maneuvers — There are three important maneuvers to perform when evaluating the JVP: positional changes, respirophasic changes, and the abdominojugular reflux.

Positional changes — The height of the jugular venous pulsation in the neck will vary depending upon the position of the patient’s upper body relative to the horizontal. Specifically, when moving the patient from a supine position to a higher elevation (eg, 30 or 45 degrees off the horizontal) to ultimately a sitting position (90 degrees), the top of the jugular venous pulsation will be visible lower in the neck. As described above, a high JVP is often best seen when the patient is sitting upright.

Respirophasic changes (Kussmaul sign) — Typically, the JVP declines with inspiration (so the height of the jugular venous pulsation will move downwards in the neck towards the clavicle with inspiration). However, in some patients, there is a lack of a decrease or even an increase in JVP during inspiration, and this abnormal finding is called Kussmaul sign. Kussmaul sign is classically seen in constrictive pericarditis or restrictive cardiomyopathy but can be seen in some subjects with HF with reduced ejection fraction. A study in patients being evaluated for heart transplant demonstrated that Kussmaul physiology in the catheterization lab was a risk factor for subsequent adverse clinical outcomes [33].

Kussmaul sign is observed in a number of conditions:

●Constrictive or effusive pericarditis – Other findings suggestive of chronic pericardial constriction include sharp y descent, diastolic left parasternal impulse, and pericardial knock. (See "Constrictive pericarditis: Diagnostic evaluation" and "Differentiating constrictive pericarditis and restrictive cardiomyopathy".)

●Restrictive cardiomyopathy. (See "Restrictive cardiomyopathies".)

●RV infarction – In patients with inferior or inferoposterior acute myocardial infarction, the presence of Kussmaul sign almost invariably indicates predominant RV infarction [34-36]. (See "Right ventricular myocardial infarction".)

●Severe RV dysfunction.

●Massive pulmonary embolism. (See "Epidemiology and pathogenesis of acute pulmonary embolism in adults" and "Clinical presentation, evaluation, and diagnosis of the nonpregnant adult with suspected acute pulmonary embolism".)

●Partial obstruction of the venae cavae. (See "Malignancy-related superior vena cava syndrome".)

●Right atrial and RV tumors. (See "Cardiac tumors".)

●Severe tricuspid regurgitation. (See "Etiology, clinical features, and evaluation of tricuspid regurgitation".)

●Tricuspid stenosis. (See "Tricuspid stenosis".)

●Cardiac tamponade (rarely). (See "Cardiac tamponade".)

The various causes are generally distinguished by associated clinical signs and imaging, particularly echocardiography.

The mechanism of Kussmaul sign in all these conditions is not entirely clear. In patients with constrictive pericarditis, the increase in intra-abdominal pressure during inspiration appears to contribute to the increase in CVP [37].

Abdominojugular test — The abdominojugular test (also known as abdominojugular or hepatojugular reflux) is a means of increasing venous return and pressure and thus facilitating analysis of the jugular venous pulse. The abdominojugular reflux is assessed by applying firm, sustained pressure for 10 seconds over the upper right or mid abdomen while the patient is breathing quietly. Normally, this maneuver transiently increases JVP (eg, a transient flicker for two to three cardiac cycles). With positive abdominojugular reflux (an abnormal test), the JVP will increase and stay elevated for at least 10 seconds of compression. A positive hepatojugular reflux is associated with the presence of an elevated pulmonary capillary wedge pressure of 15 mmHg or higher such as in patients with dilated cardiomyopathy [38].

The mechanism for this phenomenon has not been clearly elucidated. Impaired RV compliance may lead to an abnormal response to the increased preload caused by increased venous return and the raised diaphragm caused by abdominal compression and elevated intra-abdominal pressure [39]. A raised diaphragm during abdominal compression compromises cardiac filling by decreasing the intrathoracic and mediastinal volumes available for cardiac expansion.

SUMMARY AND RECOMMENDATIONS

●The most common indication for evaluating the jugular venous pulse is to determine whether right atrial pressure (RAP) is low or high and how it changes over time, including its response to medical therapy. RAP estimation is an important component of the evaluation of heart failure (HF). (See 'Indications' above and 'To estimate right atrial pressure' above and 'To identify and assess heart failure' above.)

●The JVP is an estimate of the RAP and is not a direct measure of left ventricular filling pressures (such as left atrial pressure or pulmonary capillary wedge pressure [PCWP]). However, in most patients with chronic HF, the RAP and PCWP are concordant (both are either elevated or not elevated). (See 'To identify and assess heart failure' above.)

●Evaluation of jugular venous pulse is also helpful in the diagnosis and evaluation of a variety of cardiovascular disorders including superior vena cava obstruction, tricuspid valve disease, and pericardial disease. (See 'Indications' above and "Malignancy-related superior vena cava syndrome" and "Examination of jugular venous waveforms".)

●The right internal jugular vein (IJV) pulse is generally preferred for assessing right heart hemodynamics since the right IJV is in a direct line with the superior vena cava. If the right IJV pulsation is not visible, then the left IJV or the external jugular venous pulsations are generally helpful. (See 'Which jugular vein to examine' above.)

●The two most common problems encountered when estimating the JVP are difficulty distinguishing venous and arterial pulsations and failing to identify the venous pulse. (See 'Troubleshooting' above.)

●The RAP is estimated by adding the height of the jugular venous column above the sternal angle (JVP height) to the vertical distance from the mid-right atrium to the sternal angle (generally assumed to be 5 cm). (See 'General principles' above.)

●Elevated JVP generally reflects increased RAP but may also be caused by superior vena cava obstruction or increased intrathoracic pressure. (See 'Causes of elevated jugular venous pressure' above.)

●Kussmaul sign is the lack of a decrease or even an increase in JVP during inspiration. Kussmaul sign is classically seen in constrictive pericarditis or restrictive cardiomyopathy but is also seen in other disorders including some patients with HF. (See 'Respirophasic changes (Kussmaul sign)' above.)

●The abdominojugular test is performed by applying pressure for 10 seconds over the patient’s upper right or mid abdomen. With a positive (abnormal) abdominojugular test, the JVP will increase and stay elevated for at least 10 seconds of compression; this is associated with the presence of an elevated PCWP. (See 'Abdominojugular test' above.)

ACKNOWLEDGMENTS

The UpToDate editorial staff acknowledges Bernard Gersh, MB, ChB, DPhil, FRCP, MACC, and Catherine M Otto, MD, who contributed to earlier versions of this topic review.

The UpToDate editorial staff also acknowledges Kanu Chatterjee, MB, FRCP, FCCP, FACC, MACP (deceased), who contributed to an earlier version of this topic.