Venous Pulse Introduction
Venous pulse is defined as the pressure changes transmitted in the form of waves from the right atrium to the veins near the heart.
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Venous pulse is observed only in larger veins near the heart such as the jugular vein.
Evaluation of the venous pulse is an integral part of the physical examination because it reflects right aLfen pressure and hemodynamic events in the right atrium
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Significance
- Venous pulse recording is used to determine the rate of atrial contraction, just as the record of arterial pulse is used to determine the rate of ventricular contraction.
- In addition, many phases of the cardiac cycle can be recognized by means of venous pulse tracing.
- It is a simple and accurate method to measure the duration of different phases in diastole.
- It also represents the atrial pressure changes taking place during the cardiac cycle.
Examination Of Venous Pulse
- Inspection of jugular vein pulsations is routinely done by bedside examination of neck veins.
- It provides valuable information about cardiac function.
- To observe the pulsation of the internal jugular vein, the head of the subject is tilted upwards at 45°.
- However, m patients with increased venous pressure, the head should be tilted as much as 90°.
- The pulsations of the jugular vein cm be noticed when light is passed across the skin nv&upng the internal jugular vein with relaxed neck muscles.
- Kaneous palpation of the left carotid artery helps the examiner confirm the venous pulsations.
Methods To Record Venous Pulse
A small funnel covered by a thin rubber membrane is placed over the skin at the level of the external jugular vein in the supraclavicular fossa.
Slight pressure is exerted to provide perfect contact between the edge of the funnel and the skin.
The pressure changes in the vein cause some oscillations in the rubber membrane through the skin.
The oscillations are transmitted through a rubber tube to a recording device like Marey’s Tambour. Nowadays electronic transducer is used for this purpose.
The subject should be in such a position to avoid the effect of gravity, which tends to empty veins and reduce the amplitude of the venous pulse.
Recording Of Venous Pulse – Jugular Venous Pulse Tracing
The recording of the jugular venous pulse is also called a phlebogram. It is similar to the intra-atrial pressure curve.
Like the intra-atrial pressure curve, the phlebogram also has three positive waves—a, c, v and three negative waves— x, x y.
‘a’ Wave
It is the first wave and is a positive wave. The rise in pressure is due to atrial systole. It precedes ventricular systole.
‘x’ Wave
It denotes the fall of pressure in the atrium and coincides with atrial diastole and the beginning of ventricular systole.
‘c’ Wave
Previously, it was thought to be due to the transmission of the pulse from the neighboring carotid artery.
Hence, it was called the ‘c‘ wave. Now, it is known that this wave occurs due to a rise in atrial pressure during the isometric contraction period.
During this period the atrioventricular valves bulge into the atria and increase the pressure in the atria slightly.
‘X1’ Wave
It is obtained due to a fall in pressure during the ejection period. During the ejection period, the atrioventricular ring is pulled towards the ventricles causing distention of atria.
So, the atrial pressure falls.
‘V’ Wave
It shows a rise in pressure in the atria. The pressure increases because of the filling of the atria (venous return).
It is obtained during the isometric relaxation period or during atrial diastole.
‘y’ Wave
It denotes a fall in pressure in the atria. It is due to the opening of the atrioventricular valve and the emptying of blood into the ventricle.
It appears during rapid and slow filling periods, the ‘y’ wave is followed by the ‘a’ wave and the cycle is repeated.
Applied Physiology – Abnormal Venous Pulse
Elevated Jugular Venous Pulse
The elevated jugular venous pulse indicates the rise in right ventricular pressure which occurs in:
- Bradycardia
- Pericardial effusion
- Constrictive pericarditis
- Tricuspid stenosis
- Pulmonary hypertension.
El Kussmaul’s Sign
Kussmaul’s sign is the increase in venous distention and venous pressure which occurs during inspiration.
It indicates the heart diseases such as:
- Cardiac tamponade
- Constrictive pericarditis
- Restrictive cardiomyopathy
- Right ventricular infarction.
Abnormalities Of Waves In Jugular Pulse Tracing
1. Elevation of ‘a’ Wave
Elevation of ‘a’ wave occurs in:
- Tricuspid stenosis
- Pulmonary hypertension.
2. Cannon ‘a’ Wave
A Giant ‘a’ wave with abrupt fall is called Cannon ‘a ‘ wave. It appears in:
- Complete heart block
- Paroxysmal AV nodal tachycardia
- Ventricular tachycardia.
3. Abnormal V Wave
‘V’ wave becomes abnormal in tricuspid incompetence
4. Abnormal ‘x’ Wave
Abnormal ‘x’ wave appears in:
- Atrial fibrillation
- Cardiac tamponade
- Constrictive pericarditis
5. Abnormal y Wave
‘y’ wave becomes abnormal in:
- Tricuspid regurgitation
- Constrictive pericarditis.
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