Canine Myocardial Disease Flashcards
What’s the most common signalment for dilated cardiomyopathy?
medium to large breed
- Doberman Pincher, Irish Wolfhound, Great Dane, Cocker Spaniel
What abnormalities can be noted on physical exam for DCM?
There are 2 stages: asymptomatic and symptomatic
- symptomatic: soft murmur and/or gallop rhythm
Which biomarker is the most useful for detecting both occult and overt DCM?
NT-proBNP
What would an underlying condition that can lead to DCM in Cocker Spaniels?
Taurine deficiency
What type of diet could potential increase risk of DCM in dalmatian?
low protein
What are some screening criteria for adult Doberman for DCM?
On echocardiogram: mild enlargement of L ventricle
On ECG: more than 50 VPCs in 24h, or with couples or triplets
What’s the most common presenting signs for Great Dane with DCM?
- weight loss, coughing
- may be X-linked
- ECG = atrial fibrillation with occasional VPCs
What’s the disease progression of DCM in Irish Wolfhounds?
- autosomal recessive
- tends to be slower
- atrial fibrillation may be the first sign, and no CHF until 2 years later
- sudden death still possible
How common is heart murmur for Newfoundland with DCM?
- not common!
- still has atrial fibrillation, some VPCs
- common complaint = dyspnea, cough, inappetance, ascites with L or biventricular heart failure
- no gender predilection
At what age can Portuguese Water Dog develop DCM?
They have a juvenile form of familial DCM that can occur at 2-32 weeks old
- sudden collapse/ death possible
(similar to Toy Manchester terriers)
What’s the pattern of inheritance for familiar Giant Schnauzer with DCM?
Autosomal recessive
At what age can Toy Manchester terriers develop DCM?
< 1 years old, similar to Portuguese Water dog
How is occult DCM treated?
- ACEi
- Pimobendan
- cautious with beta blockers
How is overt DMC treated?
- Pimobendan –> balanced vasodilation, positive inotrope
- ACEi
- diuretics
How is ventricular arrhythmia managed in patients with DCM?
- not sure if treatment is truly warranted as the association with sudden death is not well studied
- if needed, can try beta blocker (ex. sotalol) and potassium channel blocker (ex. amiodarone) –> use cautiously if systolic dysfunction is presnet
What’s the most common clinical signs of boxer cardiomyopathy?
aka arrhythmogenic right ventricular cardiomyopathy
- ventricular arrhythmia
- syncope = most common
- sudden death
How is Boxer cardiomyopathy diagnosed?
- Holter: >100 VPCs. left BBB, couplets, or triplets
- CXR = often normal
- Echo = looks for ventricular dilation and systolic function – may still be normal
When should Boxer cardiomyopathy be treated?
- could consider treatment is there is:
>1000 VPCs in 24hs
ventricular tachycardia
evidence of R-on-T phenomenon
homozygous for the striation mutation (known to have more sever disease) - but anti-arrhythmic for ventricular arrhythmia can also lead to more arrhythmia, and there is no clear indications that treatment will decrease the risk of sudden death
How is Boxer cardiomyopathy treated?
With syncope and ventricular tachycardia:
- sotalol, maxiletine
If there is echo findings of systolic dysfunctions and ventricular dilation –> treat like DCM
- pimobendan, ACEi, diuretics
What’s myocarditis?
presence of myocardial necrosis, or degeneration & inflammation
What are some infectious agents that can cause myocarditis?
- Chagas’ disease (Trypanosoma cruzi)
- R sided heart failure
- ECG abnormalities
- sudden death
- lymphadenopathy! - Leishmania
- parasite can be in the myocardium
- 1st degree AV block - Parvo enteritis (uncommon cause for myocarditis)
- West Nile (also uncommon cause of myocarditis)
What are some other uncommon causes of myocardial disease in dogs?
- hypothyroidism –> reduction in L ventricular fractional shortening
- myocardial infarcts –> associated with thromboembolic state
- hypertrophic cardiomyopathy –> concentric hypertrophy of the interventricular septum and L ventricular free wall
