Medicine Marrow Pg 371-375 (Cardiology)

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Questions and Answers

What is the mechanism of the x descent in the cardiac cycle?

Atrial relaxation (correct)

Ventricular relaxation

Ventricular contraction

Atrial filling

The v wave occurs primarily during diastole.

False

What condition might lead to a prominent v wave?

Tricuspid regurgitation (TR)

A reduced or absent x descent can be seen in conditions such as _______.

right ventricular failure (RVF) Signup and view all the answers

Match the following conditions with their associated features:

Cor pulmonale = Prominent v wave Hypotension = Reduced v wave Right ventricular failure = Prominent v wave Atrial fibrillation = Reduced x descent Signup and view all the answers

What causes a large 'a' wave in the jugular venous pulse?

Tricuspid stenosis Signup and view all the answers

A giant 'a' wave is associated with atrial contraction against a closed tricuspid valve.

True Signup and view all the answers

What does the 'c' wave in the jugular venous pulse represent?

Upward bulge of the tricuspid valve during isovolumetric contraction Signup and view all the answers

An _____ 'a' wave indicates that there is atrial fibrillation present.

absent Signup and view all the answers

Match the following conditions with their associated jugular venous pulse findings:

Regular arrhythmia = Giant a wave Atrial fibrillation = Absent a wave RV hypertrophy = Large a wave Tricuspid stenosis = Large a wave Signup and view all the answers

Which condition is associated with a pulseless rise in JVP?

SVC obstruction Signup and view all the answers

Kussmaul's sign indicates a decrease in JVP during inspiration.

False Signup and view all the answers

What does an RA pressure greater than 8 cm H₂O indicate?

Elevated RA pressure Signup and view all the answers

Elevated JVP can be a result of pressure and compliance of the right ventricle.

increased Signup and view all the answers

Match the following causes of elevated JVP with their related conditions:

SVC obstruction = Pulseless rise in JVP Tricuspid stenosis = RV inflow impedance Renal failure = Circulatory overload Chronic constrictive pericarditis = Kussmaul's sign Signup and view all the answers

What is the primary cause of a rapid Y descent in JVP?

Chronic Constrictive Pericarditis (CCP) Signup and view all the answers

A prominent a wave in JVP is associated with pulmonary hypertension.

True Signup and view all the answers

During which phase of the cardiac cycle does the Y descent occur?

Diastole Signup and view all the answers

The H wave occurs _____ to an A wave during long diastole due to decreased heart rate.

just prior Signup and view all the answers

Match the following cardiac conditions with their effects on JVP:

Aortic Stenosis (AS) = Usually no change in JVP Aortic Regurgitation (AR) = Usually no change in JVP Mitral Regurgitation (MR) = Usually no change in JVP Tricuspid Stenosis (TS) = Associated with a prominent a wave Signup and view all the answers

Which of the following characteristics is true for the jugular venous pulse (JVP)?

Digital compression abolishes the venous pulse. Signup and view all the answers

Abdominal compression has no effect on JVP.

False Signup and view all the answers

What does an increase in JVP after 10 seconds of periumbilical compression indicate?

Impending right heart failure Signup and view all the answers

To measure JVP, the patient should be positioned at a _____ degree angle.

45 Signup and view all the answers

Match the characteristics to the respective types of pulses:

IJV Pulse = Has two peaks and two troughs Carotid Pulse = Deeper and medial in the neck Signup and view all the answers

Study Notes

x Descent

Occurs during atrial relaxation in diastole
A prominent x descent is seen in constrictive pericarditis (CCP) and cardiac tamponade (CT)
A reduced or absent x descent is seen in right ventricular failure (RVF), tricuspid regurgitation (TR), and atrial fibrillation (AF)

V Wave

Occurs during atrial filling, primarily in systole, just before the peak of the v wave
A prominent v wave is often caused by increased right atrial volume during ventricular systole
- Common causes include:
  - Tricuspid regurgitation (TR)
  - Cor pulmonale
  - High superior vena cava pressure due to RVF
  - Right ventricular hypertrophy
  - Atrial septal defect (ASD) with mitral regurgitation (MR)
A reduced v wave is seen in states of hypovolemia and hypotension

a Wave

Represents atrial contraction in diastole, just before systole
Precedes the upstroke of the carotid pulse and follows the P wave of the ECG
A large a wave is indicative of the atria contracting against resistance
- Common causes include:
  - Right ventricular hypertrophy
  - Right ventricular hypertrophy
  - Tricuspid stenosis (TS)
  - Right atrial myxoma
  - Pulmonary hypertension
A giant a wave (Cannon a wave) is caused by the atria contracting against a closed tricuspid valve
- In regular rhythms, this is seen in:
  - Atrioventricular nodal reentrant tachycardia (AVNRT)
  - Atrioventricular reentrant tachycardia (AVRT)
- In irregular rhythms, this is seen in:
  - Ventricular tachycardia with atrioventricular dissociation
  - Complete heart block (CHB)
An absent a wave is seen in:
- Atrial fibrillation (AF)
- Hyperkalemia (increased serum potassium)

c Wave

Represents the upward bulge of the tricuspid valve during isovolumetric contraction and coincides with the first heart sound (S₁)

Y Descent

Represents right atrial emptying, leading to a decrease in right atrial pressure
Occurs in diastole, following the opening of the atrioventricular valve
A rapid y descent is seen in constrictive pericarditis, also known as Friedreich’s sign
- It is seen in conditions causing prominent V wave.
A slow y descent is seen in:
- Tricuspid stenosis (TS)
- Right atrial myxoma
- Impaired right atrial emptying and right ventricular filling

h Wave

A small wave that appears just prior to the a wave in long diastole due to a decreased heart rate

Other Important Information

Aortic stenosis (AS), aortic regurgitation (AR), and mitral regurgitation (MR) usually do not cause changes in JVP
Mitral stenosis (MS) causes a prominent a wave due to pulmonary hypertension
A Jugular Venous Pressure (JVP) greater than 3 cm above the sternal angle is considered elevated
Right atrial pressure is calculated by adding 5 to the JVP height in centimeters (cm H₂O)
A right atrial pressure greater than 8 cm H₂O is considered elevated
Right ventricular end-diastolic pressure is equal to right atrial pressure

Causes of Elevated JVP

A pulseless rise in JVP is indicative of superior vena cava obstruction. All other causes lead to a pulsatile rise.
Circulatory overload can cause an elevated JVP and is seen in:
- Renal failure
- Liver cirrhosis
- Excessive fluid administration
Increased right ventricular pressure and decreased compliance can lead to an elevated JVP and is seen in:
- Pulmonary stenosis
- Pulmonary hypertension
- Right ventricular failure/right ventricular hypertrophy
- Right ventricular infarction
Right ventricular inflow impedance can cause elevated JVP and is seen in:
- Tricuspid stenosis (TS)/atresia
- Right atrial myxoma
- Chronic constrictive pericarditis

Kussmaul's Sign

An increase in JVP with inspiration
Indicative of:
- Constrictive pericarditis (CCP)
- Tricuspid stenosis (TS)
- Restrictive cardiomyopathy (RCM)

Abdominojugular Reflex (AJR)

Previously known as the Hepatojugular reflex
Performed by compressing the periumbilical region for 10 seconds
A rise in JVP during the procedure suggests impending right heart failure
The principle is that abdominal compression increases venous return, which a faulty or dilated right ventricle cannot accommodate without a rise in pressure.

Measurement of JVP

The patient should be positioned at a 45° angle
Use a ruler to measure the highest point of JVP
Measure perpendicular to the ruler at the sternal angle
The sternal angle is 5 cm above the center of the right atrium

Difference between IJV and Carotid Pulses

The Internal Jugular Vein (IJV) pulse is superficial and lateral in the neck, while the carotid pulse is deeper and medial
The IJV pulse is better seen than felt, while the carotid pulse is better felt than seen
The IJV pulse has 2 peaks and 2 troughs, while the carotid pulse has a single upstroke
Descents are more obvious in the IJV pulse, while the carotid pulse has a brisker and visible upstroke
Digital compression abolishes the IJV pulse, while it has no effect on the carotid pulse
The IJV pulse falls during inspiration, while the carotid pulse does not change with respiration
Abdominal compression elevates the IJV pulse, but has no effect on the carotid pulse

Waveform Components

The waveform has 3 positive waves: "a," "c," and "v"
It also has 3 descents: "x descent," "y descent"

Inference

A JVP greater than 3 cm above the sternal angle is elevated
Right atrial pressure is estimated using the formula: (5 + JVP height in cm) cm H₂O
A right atrial pressure greater than 8 cm H₂O is considered elevated

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Description

This quiz explores the characteristics and clinical implications of cardiac waveforms, including the x descent, v wave, and a wave. Understand how these waves relate to conditions such as constrictive pericarditis, tricuspid regurgitation, and right ventricular failure. Test your knowledge on the physiological and pathological relevance of these waveform patterns.