The Jugular Venous Pulse And Hepatojugular Reflux Examinations Of Cardiovascular Diseases
Waves of JVP
Jugular venous Pulse
Our previous discussion was on physical examination of patients with cardiovascular diseases. You can go through it before continuing.
It is ideal to examine the internal jugular vein with the patient resting comfortably at an angle of 450. The jugular vein closely reflects the pressure changes within the right atrium. In health, at 450 incline the upper limit of the venous column lies just behind the right sternoclavicular joint, which is at the same horizontal level as the sternal angle. When right atrial pressure is increased as in right-sided heart failure, the venous column is seen above the right sterno-clavicular joint and the vertical height of this column is measured to express the increase in venous pressure.
The waves a, c and v and the troughs x and y are also studied. The jugular vein is a low pressure system and therefore, the waves are occluded easily by palpation.
'a'-wave is caused by atrial contraction and is presystolic. It is more prominent when the right atrium is contracting against increased resistance. it disappears in atrial fibrillation.
'c'-wave is small and corresponds to the onset of ventricular systole.
'v'-wave is systolic. In tricuspid incompetence the 'v'-wave becomes very prominent.
'x'-wave is the trough caused by drawing down of the base of the ventricles including the A-V ring during systole.
'y'-wave is caused by opening of tricuspid valve and rapid inflow of blood into the right ventricle.
In the ordinary case it is easy to distinguish carotid artery pulse from jugular venous pulse, but sometimes when the former is very prominent or when both coexist, difficulty may arise.
Differences between the jugular venous pulse and carotid artery pulse
1. Better seen than felt
Seen and felt well
2. Wavy column with 2-3 waves
Jerky, only one wave
3. During inspiration, the vein becomes empty and vice versa
Not much change with the phases of respiration
4. Vein becomes more prominent when the patient lies flat
5. Hepatojugular reflux present
the visible Jugular vein
The Hepatojugular reflux
While observing the jugular vein, the abdominal wall is pressed. Rise in intra-abdominal pressure crives blood from the liver to the inferior vena cava, thus increasing the venous return to the heart. This results is rise of the jugular venous pressure. Release of abdominal pressure promptly brings back jugular venous pressure also to the normal level. In early right-sided heart failure, abdominal pressure raises the jugular venous pressure, but release of the pressure is not followed by prompt fall of the jugular venous column.
Proper examination of the jugular venous pulse is a simple and very reliable bedside method to assess the hemodynamic events in the right atrium and it is absolutely essential that the clinical student spends time to learn this technique fully.
JVP is increased in right-sided heart failure, in which this is the earliest sign. Hypervolemic states (overhydration) lead to engorgement of the jugular (e.g acute nephritic syndrome). Study of the wave pattern helps in diagnosis arrhythmias such as atrial fibrillation, atrial flutter, and a-v dissociation. Cannon waves are jugular venous waves occurring in conditions such as complete heart block or extrasystoles when the atrium contracts against a closed tricuspid valve. This results in fusion of a giant 'a' wave with part of c, x or v (systolic waves) and the wave often reaches up to the angle of the mandible. Regular cannon waves may occur in junctional rhythm and 2:1 A-V block. Irregular cannon waves are more common and occur in complete heart block and ectopic beats (atrial, ventricular or junctional).
© 2013 Funom Theophilus Makama