Endocardial disease

• Two types of endocardial disease

  Acquired form - CDVD (most common), endocarditis (rare)

  Congenital form - valve dysplasia’s (insufficient valve, Stenotic valve)
• How does chronic valve disease occur?

  Myxomatous degeneration of mitral and/or tricuspid valve (usually mitral or mitral and tricuspid together, less likely to be tricuspid only).

  Rarely affects aortic/pulmonic valves in small animals.

  Thickening and redundency of heart valve leaflets. Prominent nodular thickenings.
• Why is CDVD a problem?

  As the valve get thicker, doesnt shut adequately. Causes blood regurgitation from ventricles to the atria. Causes and enlarged atria as the back flow means the atria is dealing with way more blood than normal.
• Breeds affected with CDVD

  • Small breeds overrepresented (congenitally prone)
  • Cavalier King Charles Spaniels
  • Poodles
  • Chihuahua
  • Maltese
  • Shih Tzu
  • Middle - older age
• How do CDVD present?

  Exercise intolerance

  Increased respiratory effort and rate

  Coughing (usually because of pulmonary oedema that develops, not the enlarged heart).

  Decreased appetite

  However may present for a booster and you find a heart murmur incidentally with no other clinical signs
• Grading heart murmurs

  • Grade I - quiet only heard after few minutes in a quiet room
  • Grade II - quiet but easily audible
  • Grade III - same intensity as the heart sounds
  • Grade IV - a murmur louder than heart sounds but no precordial thrill.
  • Grade V - very loud murmur and precordial thrill present
  • Grade VI - murmur audible when stethoscope removed from chest wall.
• Staging heart disease in Dogs

  Stage A - Dogs at high risk for heart disease (KCC)

  Stage B - a murmur is heard but there are no visible signs of heart failure.

  B1 - The heart does not appear enlarged or changed on x-ray.

  B2 - The heart does appear enlarged or changed on X-ray

  Stage C - Evidence of heart failure is visible and treatment is necessary.

  Stage D - Heart failure is getting hard to manage and is not responding to standard treatment.
• Left sided cardiomegaly

  Elevation of distal trachea (left atria gets bigger and pushes the trachea up and away).

  Increased cardiac silhouette height.

  Straightening of caudal border of the heart and loss of cardiac waist.

  Tenting of LA

  Splitting of main stem bronchi

  Bulge on cardiac silhouette at 2-3 o’clock in DV = L atrial appendage.