Cardiac murmurs in LA

Question 1

What types of murmurs are usually not associated with valve pathology?

Answer 1

Aortic flow murmur, ventricular flow murmurs, valve regurgitations (mitral, tricuspid or aortic) - (may be pathological depending on C.S and type of murmur)

Question 2

If you have a quiet, early/mid systolic murmur, heart base, no radiation in a fit young horse that disappears with excercise, what kind of murmur would be your top differential?

Answer 2

Aortic Flow Murmur

Question 3

What kind of murmur would you expect with an aortic flow murmur?

Answer 3

Euiet, early/mid systolic murmur, heart base, no radiation, often in a fit horse, often disappears with excercise

Question 4

What is the significance of aortic flow murmurs?

Answer 4

Functional murmurs that are common in normal fit horses, normally disappear with excercise. Most common functional murmur.

Question 5

If you have a high pitched squeak or whoop, early diastolic, at the heartbase or AV valves (may be either side) with short duration in a young thoroughbred in training, what kind of murmur would be your top differential?

Answer 5

Ventricular Flow Murmur (mitral or tricuspid)

Question 6

What kind of murmur would you expect with a Ventricular Flow Murmur (mitral or tricuspid)?

Answer 6

High pitched squeak or whoop, early diastolic, at the heartbase or AV valves (may be either side) with short duration, normal especially in young thoroughbred in training

Question 7

What is the significance of ventricular flow murmurs?

Answer 7

Less common than aortic flow murmurs, but still normal in young fit TB’s

Question 8

If you have a early/mid/holosystolic, quiet, plateau, left 5th intercostal space, that radiates caudo-dorsally, what kind of murmur would be your top differential?

Answer 8

Mitral regurgitation (probably a functional murmur as it’s quiet, though probably investigate)

Question 9

What kind of murmur would you expect with a Mitral regurgitation murmur?

Answer 9

Early/mid/holosystolic, quiet, plateau, left 5th intercostal space, that radiates caudo-dorsally

Question 10

What is the significance of mitral regurgitation murmurs?

Answer 10

Quiet ones are often ‘functional murmurs’. However, they can be pathological and significant, and if very severe can cause sudden death from rupture of PA.

Question 11

What signs would suggest that a mitral regurgitation murmur may be significant rather than a functional murmur?

Answer 11

Poor performance, resting tachycardia (>40-60), abnormal pulses, signs of LSHF, arrthyhmia’s (esp AF), louder than grade 4, wide radiation

Question 12

If you have a early/mid/holosystolic, quiet, plateau, right 4th intercostal space, that radiates cranio-dorsally, what kind of murmur would be your top differential?

Answer 12

Tricuspid regurgitation (probably a functional murmur as it’s quiet, though probably investigate)

Question 13

What kind of murmur would you expect with a Tricuspid regurgitation murmur?

Answer 13

Early/mid/holosystolic, quiet, plateau, right 4th intercostal space, that radiates cranio-dorsally

Question 14

What is the significance of tricuspid regurgitation murmurs?

Answer 14

Quiet ones are often ‘functional murmurs’. However, they can be pathological and significant

Question 15

What signs would suggest that a tricuspid regurgitation murmur may be significant rather than a functional murmur?

Answer 15

Poor performance, resting tachycardia (>40-60), abnormal pulses, signs of RSHF, arrthyhmia’s (esp AF), louder than grade 4, wide radiation

Question 16

If you have a holodiastolic, quiet, decrescendo, left base, that radiates caudo-ventrally and to RHS, what kind of murmur would be your top differential?

Answer 16

Aortic regurgitation (may be incidental, but usually PROGRESSIVE)

Question 17

What kind of murmur would you expect with an Aortic regurgitation murmur?

Answer 17

Holodiastolic,decrescendo, left base, that radiates caudo-ventrally and to RHS.

Question 18

What is the significance of aortic regurgitation murmurs?

Answer 18

More common in older horses and may be an incidental finding, however it is usually PROGRESSIVE.

Question 19

What signs would suggest that a aortic regurgitation murmur may be a significant murmur?

Answer 19

Poor performance, resting tachycardia (>40-60), abnormal pulses (bounding), signs of LSHF, arrthyhmia’s (esp AF), louder than grade 4

Question 20

What types of valve pathology would you expect to cause a murmur in LA?

Answer 20

Degenerative valve disease (can be bacterial endocardiosis), valve prolapse, ruptured chordae tendinae, AV regurgitation secondary to ventricular dilation.

Question 21

What is the significance of degenerative valvular disease in horses?

Answer 21

Commonest form of valve pathology, can happen in any valve especially aortic. Often secondary to bacteraemia (bacterial endocardiosis), get nodular lumps on valves.

Question 22

What is the significance of valve prolapse in horses?

Answer 22

Cause mid-systolic crescendo-decrecendo murmur in any valve. It causes non-progressive regurgitation.

Question 23

What is the significance of ruptured chordae tendinae in horses?

Answer 23

Causes sudden death or signs of acute cardiac failure. It can occur spontaneously or secondary to degeneration. It is more common in the mitral valve,

Question 24

What is the most common congenital heart defect in horses?

Answer 24

Ventricular septal defect

Question 25

If you had a holosystolic, diagonal murmur (right and left side), with wide radiation, what would be your top differential?

Answer 25

VSD

Question 26

What kind of murmur would you expect with a VSD?

Answer 26

Holosystolic, diagonal murmur (right and left side), with wide radiation

Question 27

In a VSD, what are the right and left systolic murmurs associated with?

Answer 27

Right = Left to right shunt
Left = Increased blood in RV, so will get a pulmonic flow murmur due to increased blood flow through valve.

Question 28

If you had a continuous murmur, grade 3-5, on the left heart base in a foal, what would be your top differential?

Answer 28

PDA

Question 29

What kind of murmur would you expect in a PDA?

Answer 29

Continuous murmur, grade 3-5, on the left heart base

Question 30

Which is the best way to identify heart murmurs in horses: Echo or ECG?

Answer 30

Echo ALWAYS. ECG only tells you about rate and rhythm.