Equine Pericardial, Myocardial, & Vascular Diseases Flashcards
How does pericarditis manifest?
uncommon in horses —> often an emergency!!
What are the 3 most common infectious causes of pericarditis? Other causes?
- BACTERIAL: Actinobacillus spp., Streptococcus
- VIRAL
- FUNGAL
(commonly secondary to penumonia)
- immune-mediated
- traumatic
- neoplasia
What are the 2 most common risk factors that predispose horses to pericarditis?
- extension of pleural pneumonia in horses that have been transported, fever, and exposure to a large number of horses
- high prevalence in mare reproductive loss syndrome caused by Eastern Tent Caterpillar
What is the theory to Eastern Tent Caterpillars causing mare reproductive loss syndrome?
- ETC nests in trees
- ETC hatch in Feb-March and larvae migrate to find pupation site
- horses ingest ETC and their setae hairs break off and lodge in the stomach lining, which carries gut bacteria into tissue and bloodstream
- setae carry bacteria to immuno-sensitive areas, such as placental/fetal membranes and the heart
(late-term abortion storms)
What is the consequence to infectious pericarditis?
impaired cardiac filling causes cardiac tamponade and pericardial construction, which leads to right-sided CHF —> peripheral edema, bilateral jugular pulsation
What are the 3 forms of infectious pericarditis?
- effusive
- fibrinous (cows!)
- constrictive
What are the most common clinical signs associated with infectious pericarditis?
- respiratory distress: tachypnea, tachycardia
- fever
- colic, weight loss
- jugular distension and pulsation, weak pulse
- ventral edema, ascites
- pericardial friction rub, muffled heart sounds, pleural effusion
- cardiac tamponade
What are the 3 determinants to the severity of infectious pericarditis clinical signs?
- distensibility of pericardial sac
- rate of fluid accumulation
- amount of fluid accumulation
What 4 clinical pathology findings are seen in patients with infectious pericarditis?
- anemia
- hyperproteinemia
- hyperfibrinogenemia
- neutrophilic leukocytosis
What is the diagnostic modality of choice to diagnosing infectious pericarditis?
echocardiography —> shows amount and character of fluid and degree of cardiac compromise
Infectious pericarditis, fibrin accumulation:
What 3 things are seen on ECG in patients with pericarditis?
- small amplitude QRS
- sinus tachycardia
- PVC
What 2 things are seen on radiographs in patients with pericarditis? What can it not differentiate?
- globulus heart with effusion
- infiltrates and enlarged pulmonary vessels
doesn’t differential from other forms of cardiac enlargement
What is recommended for pericarditis treatment? What is prognosis like?
- stall rest
- drainage and lavage with ECG monitoring
- local and systemic antimicrobials
- NSAIDs
- steroids to decrease inflammation if idiopathic
guarded to fair due to lengthy, hard treatment course
What is the difference between right-sided and left-sided heart failure?
R = peripheral edema, ascites, jugular distension and pulsation
L = pulmonary edema, effusion, tachypnea, tachycardia
What is heard on auscultation in right-sided and left-sided heart failure?
R = splitting S2
L = crackles, prominent S3
What are the 4 most common etiologies of myocarditis?
- bacteria
- virus
- parasites
- thromboembolic
What are 4 consequences of myocarditis?
- decreased myocardial contractility and ventricular ejection fraction
- diastolic dysfunction with impaired ventricular filling
- mitral and tricuspid valve incompetency
- development of arrhythmias
What are the most common clinical signs of myocarditis?
- fever
- tachypnea
- arrhythmias
- signs of CHF
- myalgia, reluctance to move, exercise intolerance
- tachypnea, lethargy, depression
- ataxia, staggering, recumbency
- sudden death
What clinical pathology is seen in patients with myocarditis? What are 2 signs on ECGs?
increased cardiac enzyme, troponin I
- sinus tachycardia
- cardiac arrythmias
What treatments of myocarditis are recommended?
- supportive care: rest*
- corticosteroids*
- Digoxin
- Quinidine sulfate
- Lasix
(remove underlying cause!)
In what animals is the use of ionophores common?
- POULTRY: coccidiostat
- CATTLE: growth promoter
(TOXIC IN HORSES)