Canine Top Cardiac Diseases - Part 2 Flashcards
what is the classic case presentation of pulmonary hypertension?
middle aged to older dog with coughing, respiratory distress, exercise intolerance, syncope (common!!), ascites, & a variety of things on cardiac auscultation (range of murmurs, split second heart sounds, pulmonary crackles)
what are the possible etiologies of pulmonary hypertension?
mitral valve regurge causing chronic increased left heart pressures, chronic hypoxia (right to left shunt, chronic respiratory disease), & HWD
what is seen on throacic rads for a dog with pulmonary hypertension?
cardiomegaly, pulmonary artery dilation, tortuous pulmonary arteries, dilated caudal vena cava, & interstitial/alveolar/bronchial pattern
what is seen on echo of a dog with pulmonary hypertension?
right ventricular hypertrophy, high velocity tricuspid valve regurg, & flattening of the interventricular septum or paradoxical septal motion which indicates high right heartpressures, & varying right atrial/ventricular dilation
how is pulmonary hypertension treated?
treat underlying disease, O2 therapy for decompensation, pimobendan, & sildenafil (phosphodiesterase inhibitor)
what does prognosis of pulmonary hypertension depend on?
effective treatment of the underlying cause & response to the specific therapy for pulmonary hypertension
what is the classic case presentation of CHF?
cough, exercise intolerance, breathing harder, ascites, harsh lung sounds/crackles, syncope, restlessness, +/- heart murmur/arrhythmia - cats may present with paraparesis & cold pelvic limbs if a saddle thrombus occurs
what does orthopnea look like in dogs? what about cats?
dogs - standing position with the head & neck extended, elbows abducted cats - crouched down but chest slightly elevated
what are the possible etiologies of CHF?
reduced myocardial contraction, valvular regurgitation, & marked diastolic dysfunction
what is seen on thoracic rads of a dog with CHF?
heart enlargement, dilated pulmonary veins, & interstitial to alveolar lung changes in the caudodorsal lung fields
what is seen on echo of a dog with CHF?
left atrial/ventricular enlargement causing pulmonary edema, right atrial/ventricular dialation causing ascites, valvular insufficiency, +/- poor contractility
what is seen on echo of a cat with CHF?
decreased diastolic dysfunction with HCM or restrictive cardiomyopathy, systoic anterior motion of the mitral valve, & echo contrast smoke in the left atrium due to the swirling of RBCs
what is the acute treatment recommended for a dog with CHF?
furosemide, O2 therapy, pimobendan, & decrease stress
what is the chronic treatment used for a dog with chronic CHF?
oral furosemide, pimobendan, ACE inhibitors, lower salt diet, exercise restriction
what is the prognosis for the initial recovery of CHF?
guarded to good - long term depends on underlying disease process
what must be monitored during chronic treatment for CHF that is crucial for titrating therapy?
renal function!!!
what is the classic case presentation of MMVD?
middle aged to older dog with exercise intolerance, cough, left sided apical murmur, +/- palpable thrill
what is the breed predilection of MMVD?
cavies, dachshunds, yorkies, chi chi, & shih tzu
what is seen on thoracic rads of a dog with MMVD?
may be normal or left atrial dilation, increased VHS, +/- pulmonary vein dilation/left mainstem bronchus compression that contributes to a cough
what is seen on echo of a dog with MMVD?
mitral valve regurge, thickening of the mitral valve leaflets, varying degress of secondary left ventricular dilation, +/- left atrial dilation/increased left atrial to aortic ratio in short axis view
what treatment is used before CHF for a dog with MMVD?
pimobendan & ace inhibitors
what treatment is used after the onset of CHF in a dog with MMVD?
diuretics, spironolactine, pimobendan, exercise restriction, & weight loss if overweight
what is the prognosis of MMVD before the onset of CHF? what about after?
before - guarded to good after - average lifespan of 1 year
T/F: newer studies indicate promise for a prolonged survival time if pimobendan is started when moderate to marked left atrial dilation is seen
TRUE
what are the top 3 arrhythmias seen in dogs? how are they all categorized?
a fib, VPCs, v tach - all present with exercise intolerance, syncope, weakness, pulse deficits, +/- heart murmur
what breeds are predisposed to a fib? what is it associated with? what about a fib secondary to atrial dilation?
a fib - large/giant breeds - great dane, newfoundland, irish wolfhounds - associated with a low heart rate & clinical signs are uncommon the other, expect to see high heart rates +/- clinical signs
what clinical signs are seen in a dog with VPC?
may be asymptomatic +/- syncope
what clinical signs are seen in a dog with v tach?
syncope & sudden death
what is the etiology of a fib in dogs? what about cats?
dogs - advanced endiocardiosis or DCM cats - advanced cardiomyopathy with severe atrial dilation
what are some potential etiologies for ventricular arrhythmias?
hypokalemia/hypomagnesemia, acidosis, anemia, GDV, endocarditis, splenic/hepatic mass, & toxicity
what does a fib look like on ECG?
rapid heart rate, absence of p waves, irregular r-r intervals
what do VPCS look like on an ECG?
bizarre & wide QRS complexes & t waves, shorter r-r intervals compared to normal QRS waves, p waves are irrgular but unrelated to the VPCs, & +/- negative QRS complexes
what does v tach look like on an ECG?
rapid & sustained heart rate (dogs - over 180 cats - over 240), caused by 4 VPCs in a row
what diagnostics should be done for a dog with an arrhythmia?
holter monitor, echo, abdominal imaging, CBC, chem, & thoracic rads
what treatment is used for lone a fib?
if heart rate is under 150, may not require therapy
what treatment is used for a fib?
if heart rate is greater than 150 or signs of heart failure - amiodarone for cardio conversion, digoxin to slow AV node conduction, & diltiazem for calcium channel blocker
T/F: VPCs don’t always require treatment
TRUE
what are the indications for treatment for VPCs?
rapid & sustained HR over 180 in big dogs, over 220 in small dogs, & 260 in cats, r on t phenomenon, complexity of VPCs (triplets, couplets, bigeminy, trigeminy), & clinical signs from the arrhythmias
what medications are used to treat VPCs?
sotalol for a beta blocker or mexilitine as an oral lidocaine analogue
how is v tach treated?
emergency lidocaine bolus & CRI - long term management of sotalol/mexilitine
T/F: a fib in a non-giant breed dog should raise concern for significant underlying cardiac disease
TRUE
what is the prognosis of VPCs?
prognosis depends on underlying cause as it may be incidental - prognosis worsens with increased frequency/complexity
what is the prognosis of v tach?
poor to grave depending on the ability to control it with meds - can lead to ventricular fibrillation & death
