Cardiac murmurs in LA Flashcards
What types of murmurs are usually not associated with valve pathology?
Aortic flow murmur, ventricular flow murmurs, valve regurgitations (mitral, tricuspid or aortic) - (may be pathological depending on C.S and type of murmur)
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?
Aortic Flow Murmur
What kind of murmur would you expect with an aortic flow murmur?
Euiet, early/mid systolic murmur, heart base, no radiation, often in a fit horse, often disappears with excercise
What is the significance of aortic flow murmurs?
Functional murmurs that are common in normal fit horses, normally disappear with excercise. Most common functional murmur.
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?
Ventricular Flow Murmur (mitral or tricuspid)
What kind of murmur would you expect with a Ventricular Flow Murmur (mitral or tricuspid)?
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
What is the significance of ventricular flow murmurs?
Less common than aortic flow murmurs, but still normal in young fit TB’s
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?
Mitral regurgitation (probably a functional murmur as it’s quiet, though probably investigate)
What kind of murmur would you expect with a Mitral regurgitation murmur?
Early/mid/holosystolic, quiet, plateau, left 5th intercostal space, that radiates caudo-dorsally
What is the significance of mitral regurgitation murmurs?
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.
What signs would suggest that a mitral regurgitation murmur may be significant rather than a functional murmur?
Poor performance, resting tachycardia (>40-60), abnormal pulses, signs of LSHF, arrthyhmia’s (esp AF), louder than grade 4, wide radiation
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?
Tricuspid regurgitation (probably a functional murmur as it’s quiet, though probably investigate)
What kind of murmur would you expect with a Tricuspid regurgitation murmur?
Early/mid/holosystolic, quiet, plateau, right 4th intercostal space, that radiates cranio-dorsally
What is the significance of tricuspid regurgitation murmurs?
Quiet ones are often ‘functional murmurs’. However, they can be pathological and significant
What signs would suggest that a tricuspid regurgitation murmur may be significant rather than a functional murmur?
Poor performance, resting tachycardia (>40-60), abnormal pulses, signs of RSHF, arrthyhmia’s (esp AF), louder than grade 4, wide radiation
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?
Aortic regurgitation (may be incidental, but usually PROGRESSIVE)
What kind of murmur would you expect with an Aortic regurgitation murmur?
Holodiastolic,decrescendo, left base, that radiates caudo-ventrally and to RHS.
What is the significance of aortic regurgitation murmurs?
More common in older horses and may be an incidental finding, however it is usually PROGRESSIVE.
What signs would suggest that a aortic regurgitation murmur may be a significant murmur?
Poor performance, resting tachycardia (>40-60), abnormal pulses (bounding), signs of LSHF, arrthyhmia’s (esp AF), louder than grade 4
What types of valve pathology would you expect to cause a murmur in LA?
Degenerative valve disease (can be bacterial endocardiosis), valve prolapse, ruptured chordae tendinae, AV regurgitation secondary to ventricular dilation.
What is the significance of degenerative valvular disease in horses?
Commonest form of valve pathology, can happen in any valve especially aortic. Often secondary to bacteraemia (bacterial endocardiosis), get nodular lumps on valves.
What is the significance of valve prolapse in horses?
Cause mid-systolic crescendo-decrecendo murmur in any valve. It causes non-progressive regurgitation.
What is the significance of ruptured chordae tendinae in horses?
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,
What is the most common congenital heart defect in horses?
Ventricular septal defect
If you had a holosystolic, diagonal murmur (right and left side), with wide radiation, what would be your top differential?
VSD
What kind of murmur would you expect with a VSD?
Holosystolic, diagonal murmur (right and left side), with wide radiation
In a VSD, what are the right and left systolic murmurs associated with?
Right = Left to right shunt Left = Increased blood in RV, so will get a pulmonic flow murmur due to increased blood flow through valve.
If you had a continuous murmur, grade 3-5, on the left heart base in a foal, what would be your top differential?
PDA
What kind of murmur would you expect in a PDA?
Continuous murmur, grade 3-5, on the left heart base
Which is the best way to identify heart murmurs in horses: Echo or ECG?
Echo ALWAYS. ECG only tells you about rate and rhythm.
