Feline Cardiomyopathies

Question 1

Functional/Physiologic murmurs in cats

Answer 1

40-60% of cats have murmurs but not structural cardiac dz
Stress related

Question 2

Differences in cats v dogs

Answer 2

cats rarely cough
Cats left sided: pulm edema and/or pleural effusion +/- pericardial effusion
Cats = arterial thromboembolisms
Many cats w/ Cv dz do not have a murmur

Question 3

What are gallop sounds?

Answer 3

low-pitched, diastolic heart sounds, abnormal in small animals

Question 4

Cardiac biomarkers

Answer 4

NT-proBNP: natriuertic pepties
false pos in symptomatic cats (not specific)
if <100pmol/L and asymptomatic NO sign cardiac dz
Cardiac toponin I

Question 5

Most common feline cardiomyopathy?

Answer 5

Hypertrophic cardiomyopathy: diffuse or regional increase in LV wall thickness with nondilated LV chamber

Question 5

Restrictive cardiomyopathy

Answer 5

Diastolic dysfunction w/ near normal wall thickness, LA or biatrial enlargement
uncommon

Question 6

Secondary HCM

Answer 6

Systemic hypertension
Hyperthyroidism
Infiltrative dz (lymphoma, myocarditis)
Acromegaly (rare)
Aortic stenosis
Hypovolemia/dehydration

Question 7

What can cause primary hypertropic cardiomyopathy?

Answer 7

Genetic mutations: maincoon, ragdoll
autosomal dominant

Question 8

Pathophysiology of primary HCM

Answer 8

Defective sarcomere&raquo_space;
impaired LV relaxation/impaired compliance> decr LV filling > CHF/ATE
Myocardial ischemia/myofiber disorg > ventricular arrhythmias

Question 9

Is HCM primarily systolic or diastolic dysfunction?

Answer 9

Diastolic
Blood should be “pulled” into LV but instead the atria has to “push” it in

Question 10

Diagnosis of HCM

Answer 10

Echo: end diastolic wall thickness measurement
diastolic (and systolic) function assessment
atrial size assessment

Question 11

3 adverse outcomes of cardiomyopathies in cats:

Answer 11

1. Sudden death
2. CHF
3. Arterial thromboembolism (smoke = atrial/auricular thrombus)

Question 12

Atenolol

Answer 12

Decr HR and contractility
Should reduce outflow obstruction
Has not been shown to delay onset of CHF
Helpful when symptomatic

Question 13

Normal feline vertebral heart score

Answer 13

<8

Question 14

At home managememt of CHF in cats

Answer 14

Furosemide
Clopidogrel +/- factor Xa inhibitor (rivaroxaban/apixaban)
ACEi or spironolactone?
Pimo?
Diltiazem, atenolol, sotalol for a-fib and tachycardia

Question 15

Pathophysiology of FATE

Answer 15

predispoding factors in CMs + LA enlargement > blood stasis and endothelial/endocardial injury > blood clumping (smoke) > LA thrombus

Question 16

Clinical recognition of FATE

Answer 16

5 P’s
Pulselessness
Pale (acute) or purple/blue foot pads
Pain: vocalization
Paresis/paralysis: hindlimbs, tail
Poikilothermia: cool/cold limbs

Question 17

Stabilization of FATE

Answer 17

Analgesia (pure mu agonist: fentanyl, methadone) +/- anxiolytic (ace)
Check lytes for hyperkalemia
Antithrombotic drugs: parenteral herparin or clopidogrel + factor Xa inhibitor
ECG monitor for hyperkalemia
r/o CHF

Question 18

One thing on BW to confirm FATE

Answer 18

Serum Creatine kinate (AST, ALT) elevated
Usuall > 10k or 100k
Normal CK in a cat w/ suspected ATE rules out ATE