DCM + RSCHF

Question 1

List 5 dog breeds predisposed to idiopathic dilated cardiomyopathy

Answer 1

Great dane, Doberman pinschers, Cockerspaniels, Dalmations, Portuguese water dogs

Question 2

Is there a sex predilection in DCM?

Answer 2

more common in males

Question 3

List some findings on echocardiogram indicative of DCM

Answer 3

i. Increased LV end systolic diameter
ii. Decreased fractional shortening
iii. Rounding of left ventricular lumen
iv. Increase LA size
v. Increased E point to septal separation (EPSS)
vi. Wall thinning apparent in advanced disease

Question 4

How would you treat a supraventricular arrhythmia associated with DCM?

Answer 4

i. Digoxin: assess renal parameters and lyte concentrations + monitor digoxin conc.
ii. + B-blocker or calcium channel blocker (ass if digoxin alone ineffective) **only if w/ positive inotrope as both these drugs are neg. inotropes

Question 5

List 2 drugs used to treat ventricular arrythmias

Answer 5

Sotalol

Mexiletine

Question 6

List 4 underlying causes of pulmonary hypertension

Answer 6

i. Left heart disease
ii. Pulmonary artery disease (causing thickening of the arteries) (Dirofilariasis, L-to-R shunts)
iii. Lung disease and/or hypoxaemia (chronic lung disease, pulmonary fibrosis)
iv. Pulmonary thrombotic or embolic disease (PTE)

Question 7

What is a potential radiographic finding of RSCHF?

Answer 7

right atrial and ventricular enlargement and dilation of the pulmonary artery but often unremarkable

Question 8

What are 3 echo findings or RSCHF?

Answer 8

i. Insufficiency of the pulmonary tricuspid valves
ii. Tricuspid valve regurgitant jet velocity
iii. Right ventricular hypertrophy; increased afterload

Question 9

List 5 DDx of RSCHF

Answer 9

1. Progression of other heart diseases
2. Pericardial disease –> effusion/constriction
3. Heartworm disease in endemic areas
4. Pulmonic stenosis in young dogs (rarely cats)
5. Advanced lung disease

Question 10

List the most common type of pericardial effusion seen in large breed dogs

Answer 10

idiopathic (constrictive/haemorrhagic) pericardial effusion

Question 11

List 4 Ddx for pericardial effusion

Answer 11

1. Neoplasia (esp. haemangiosarcomas)
2. Trauma
3. Hypoproteinaemia (multiple causes)
4. Congenital defects of pericardial sac

Question 12

Key finding of chronic pericardial effusion on PE

Answer 12

Auscult: muffled heart sounds

+ hx weakness/exercise intolerance/collapse

Question 13

US of a heart with pericardial effusion shows…

Answer 13

definitive diagnosis for effusion - see effusion in the pericardial sac and collapse of the RA and/or RV confirming cardiac tamponade *may also be able to see an atrial/auricular mass (neoplasm)

Question 14

What is electrical alternans?

Answer 14

An ECG finding that reflects the changing position of the heart w/in the pericardial fluid w/ each beat resulting in varied QRS heights.

Question 15

Actions for a cardiac tamponade

Answer 15

emergency pericardiocentesis

Question 16

Are diuretics indicated for a cardiac tamponade case?

Answer 16

No - in most cases do not shift fluids and just result in further decreased CO and dehydration