Canine Flash Notes - Dilated Cardiomyopathy Flashcards
what is the common signalment of dogs affected with DCM?
dogs 4-10 years old
males»_space;> females
large breeds - dobermans, great danes, boxers
what dog breed is known to have a juvenile onset of DCM?
portuguese water dog
what are signs of congestive heart failure caused by DCM?
cough, tachypnea, dyspnea, exercise intolerance, abdominal distension, lethargy, inappetence, weight loss, syncope, & collapse
what is the test of choice for diagnosing DCM? what would you expect to see?
echocardiogram - left ventricular eccentric hypertrophy, normal wall thickness, enlarged end diastolic dimensions, & left atrial enlargement
what may be seen on an ECG strip from a dog with DCM?
sinus tachycardia, p-mitrale, wide/tall/low voltage QRS complexes, APCs or VPCs, & atrial fibrillation
what may be seen on thoracic radiographs of a dog with DCM?
cardiomegaly, left atrial enlargement, left ventricular enlargement, pulmonary edema, & plural effusion
what cardiac dysfunction is seen with primary DCM?
eccentric hypertrophy, impaired systolic function, +/- diastolic dysfunction
what is the treatment used for DCM?
diuretics - lasix, to reduce edema/effusion
dilators - ACE inhibitors (enalapril), 2% nitroglycerin, Na-nitroprusside (dogs with severe CHF)
low sodium diet - rest, O2 therapy, taurine, l-carnitine, & exercise restriction
positive inotropes - dobutamine, digoxin, pimobendan
anti-arrhythmics_ beta blockers (atenolol) or calcium channel blockers (diltiazem)
what are 4 breeds that are predisposed to getting DCM?
dobermans, boxers, great danes, irish wolfhounds
what are 4 expected findings on echocardiogram that are supportive of DCM?
left ventricular eccentric hypertrophy - normal wall thickness & enlarged end diastolic dimensions
left atrial enlargement
functional mitral regurgitation
increased mitral valve E point to septal separation
what are 4 etiologies that can cause DCM?
genetic
diet related (taurine deficiency which is reversible in cats)
carnitine deficiency
infectious - trypanosoma cruzi
what are 2 presentations of DCM with the worst prognosis?
cats without a taurine deficiency
dobermans with atrial fibrillation & ventricular arrhythmias
what treatment is used for acute CHF due to DCM?
minimize stress, supplemental O2
treat arrhythmias
diuretics
therapeutic thoracocentesis & paracentesis
sodium nitroprusside for severe cardiopulmonary edema in dogs only
dobutamine - positive inotrope, b1 adrenergic agonist, used for severe heart failure & cardiogenic shock
what treatment is used for chronic CHF due to DCM?
sodium restricted diet
treat arrhythmias
taurine supplementation - will reverse DCM in deficient patients (dobermans & great danes not usually taurine responsive)
l-carnitine supplementation for boxers & american cocker spaniels
diuretics
ace inhibitors - decrease heart rate, decrease sodium/water retention, & vasodilation
digoxin - useful for atrial fibrillation, positive inotrope & negative chronotrope
pimobendan - positive inotrope & vasodilator, may increase survival times in dobermans
what must be well controlled prior to starting a dog with chronic heart disease due to DCM on a beta-blocker such as atenolol or metroprolol?
heart failure must be well controlled before initiating treatment!!!
used to decease cardiotoxic sympathetic effects
