Valvar Diseases- Physiology

Question 1

Which valves are found on the right side of the heart?

Answer 1

• Tricuspid valve (AV)
• Pulmonary valve (SL)

Question 2

Which valves are found on the left hand side of the heart?

Answer 2

• Mitral valve (AV)
• Aortic valve (SL)

Question 3

What is the S1 sound caused by?

Answer 3

Caused by the AV valves closing (mitral and tricuspid)

Question 4

What is the S2 heart sound caused by?

Answer 4

The Semi-lunar valves closing

Question 5

Describe the relationship between systole and diastole and the heart sounds

Answer 5

S1 is followed by systole (ventricular contraction) and S2 is followed by diastole (ventricular filling)

Question 6

What is the signifiance of palpating the carotid pulse whilst auscultating heart sounds?

Answer 6

The pulse is palpable between S1 and S2 so it is useful for identifying which sound is lub and which is dub and which are added sounds

Question 7

What is a murmur?

Answer 7

It is an abnormal heart sound caused by the abnormal movement of blood across and valves and between chambers causing turbulence

Question 8

When is S3 heard? and what causes S3 to be heard?

Answer 8

• S3 is heard in early diastole KEN-TUC-KY
• Represents thin walled, dilated left ventricle causing decelerated blood flow
• Normal in athletes and children but in normal adults= venticular systolic failure

Question 9

When is S4 heard? Which diseases can it be heard in and what causes it?

Answer 9

• Heard during late diastole (TEN-NE-SEE)
• Occurs due to increased stiffness of left ventricle, or thicker ventricular wall
• Associated with severe hypertension and ventricular hypertrophy.

Question 10

When are systolic murmurs heard? and What are the two types of systolic murmurs?

Answer 10

• Heard between S1 and S2
• ejection systolic murmur and pan-systolic murmur

Question 11

Which valvar pathologies cause ejection systolic murmurs and why? What does it sound like?

Answer 11

• LUB Whoosh DUB
• Caused by aortic or pulmonary stenosis
• If semi-lunar valves are narrowed, there will be reduced blood flow through them during systole
• Has a rise and fall

Question 12

Which valvar pathologies cause pan-systolic murmurs and why? What does it sound like?

Answer 12

• Caused by mitral and tricuspid regurgitation
• If AV valves are leaky murmur will be heard during ventricular contraction
• Continuous sound

Question 13

When is a diastolic murmur heard?

Answer 13

Between S2 and S1

Question 14

Which valvar pathologies cause diastoli murmurs?

Answer 14

• Decrescendo murmur – occurs due to aortic or pulmonary regurgitation
• Decrescendo murmur with brief increase in intensity during atrial contraction – occurs due to mitral or tricuspid stenosis.

Question 15

Expiration can help hear which type of murmurs?

Answer 15

L-sided murmurs

Question 16

Inspiration can help auscultate which type of murmurs and why?

Answer 16

Inspiration increases R-sided murmurs

Because, during inspiration, there is more negative intra-thoracic pressure which pulls more venous blood into the heart (to the right side) so there is increased preload to R side.

At same time, during inspiration, pulmonary blood volume increases and there is a decrease in blood flow from lungs to left atrium so there is decreased preload to L side.