cat with respiratory distress and hindlimb weakness workup Flashcards
What might cause a cat to have pleural effusion
1) Hypoalbuminemia
2) Pyothorax
3) Congestive heart failure
4) Chylothorax
5) Thoracic, pulmonary, or mediastinal neoplasia
6) Hemothorax (coagulopathy, trauma)
vibration of the ventricular walls during active ventricular filling
S3 (gallop sound)
final ventricular filling by atrial contraction in a poorly compliant ventricle
S4 (gallop sound)
What a differentials for weight loss in a cat
1) Inadequate diet
2) Oral or dental disease
3) Impaired use of nutrients (maldigestion, malabsorption, protein losing disease, cardic cachexia)
4) Elevated metabolism (hyperthyroidism)
5) End stage CKD
6) Chronic inflammation
For a cat presenting with peuraal effusion, gallop sounds, tachypnea, and weight loss
What diagnostics should you do
Thoracic POCUS
Consider point of care NT-proBNP
when stable: thoracic rads, echocardiogram, bloodwork, blood pressure
What heart disease in the dog leads to S3 sounds
DCM
For a cat with pleural effusion, before performing additional diagnostics, what should you do
Thoracocentesis
What should you do prior to thoracocentesis
1) Sedate with butorphanol (0.2mg/kg IM)
2) Consider empirical dose of furosemide (1mg/kg IM or IV) due to suspicion of cardiac disease
3) Provide supplemental oxygen
T/F: you can perform NT-proBNP on pleural effusion fluid
True
Different than in dogs, cats with L sided CHF can manifest with
Pleural effusion or pulmonary edema
What are your top 3 differentials for LV concentric hypertrophy in a cat *
1) Hyperthyroidism
2) Systemic Hypertension
3) Primary hypertrophic cardiomyopathy
What should you do for cases where you dont have access to an echo
consider testing for a cardiac biomarker (NT-PROBNP) through a blood sample or on pleural effusion
hormone secreted by cardiomyocytes that causes renal and sodium loss as well as vasodilation
BNP
BNP production and excretion is increase in
in response to stretch of the heart
If you have a cat with respiratory signs in which the cause of the sings is not obvious despite other diagnostic tests. How do you interpret NT-proBNP
<100 = normal (no CHF)
100-270 = abnormal, CHF is possible
> 270 = abnormal and supports the diagnosis of CHF
If you have an asymptomatic cat with cardiac risk factors (e.g murmur, arrhythmia, gallop heart sounds) How do you interpret a NT-proBNP
<100 = normal: significant heart disease can be ruled out with a high degree of accuracy
Increase of >100 = abnormal. Increased risk of having significant heart disease; recommend echocardiogram
NT-pro BNP >100 pmol/L is abnorma but if it ______ then its indicative of CHF
> 270 pmol/L
a feline cardiomyopathy with normal LV, but L atrial enlargement
Restrictive cardomyopathy (RCM)
a feline cardiomyopathy with LV concentric hypertrophy
Hypertrophic cardiomyopathy (HCM)
a feline cardiomyopathy with right atrial and ventricular dilation
Arrhythmogenic right ventricular cardiomyopathy (ARVC)
a feline cardiomyopathy with chamber dilation, systolic dysfunction
Dilated cardiomyopathy (DCM)
What is the most prevalent feline cardiomyopathy
Hypertrophic cardiomyopathy (HCM) - LV concentric hypertrophy
Restrictive cardiomyopathy (RCM) is where the ______ is normal but there is
normal LV but has L atrial enlargement
What typically cause DCM in cats
1) taurine deficiencies - now not that prevalent
2) Tachycardia mediated
What feline cardiomyopathy is caused by hyperthyroidism
1) HCM phenotype - LV concentric hypertrophy
2) RCM phenotype - normal LV wall thickness, LA dilation
What might cause HCM phenotype (Increased LV wall thickness- concentric hypertrophy)
1) Hyperthyroidism
2) Hypertension
3) Reduced preload
4) Neoplastic infiltration
5) Transient myocardial thickening
6) Acromegaly
Dietary taurine deficiency in cats causes
DCM phenotype - chamber dilation and systolic dysfunction
An ARVC phenotype has
R atrial and R ventricle dilation
End-stage HCM is when there is
Increased LV wall thickness and now systolic dysfunction
What are the stages of feline cardiomyopathy
A: Predisposed
B1: low risk- subclinical- normal to mild atrial enlargement
B2: higher risk subclincal with moderate to severe atrial enlargement
C: Current / previous CHF / ATE
D: Refractory CHF
What stage of feline cardiomyopathy is a cat with refractory CHF
D
What stage of feline cardiomyopathy is a cat with subclinical moderate / severe atrial enlargement
B2 (higher risk)
What stage of feline cardiomyopathy is a cat with a predisposition
A - maine coon, ragdoll, sphynx, bengals, norweigan forest cats
What stage of feline cardiomyopathy is a cat with sunclinical normal / mild atrial enlargement
B1 (low risk)
How do you treat cats with Stage A cardiomyopathy
No treatment, just monitor as they are predisposed
What breeds of cats are predisposed to HCM
maine coon, ragdoll, sphynx, bengals, norweigan forest cats
How do you treat cats with Stage B1 cardiomyopathy
Treatment is generally not recommended
+/- atenolol therapy if documented dynamic left ventricular outflow tract obstruction (DLVOTO)
when the mitral valve leaflet gets sucked into outflow tract causing an obstruction
diagnosed on echo
Dynamic left ventricular outflow tract obstruction (DLVOTO) if notice then do atenolol therapy
In stage B1 cats, what do you do if you notice Dynamic left ventricular outflow tract obstruction (DLVOTO)
atenolol therapy- slows heart rate and encourages mitral valve leaflet to obstruct less often
How do you treat cats with Stage B2 cardiomyopathy
Consider starting clopidogrel, even without heart failure
+/- anti-arrhythmics (atenolol or sotalol) if concurrent ventricular arrhythmias
For cats in Stage B2, what should you start if you notice concurrent ventricular arrhythmias
atenolol or sotalol
How do you treat cats with Stage C cardiomyopathy **
1) Acute decompensated heart failure
-Furosemide (1-2mg/kg boluses IM or IV or CRI)
-Supplementary oxygen
-Sedation (butorphanol)
+/- thoracocentesis
2) Chronic HF
-Furosemide (1-2mg/kg PO q12h) titrated to maintain resting RR <30 breaths per minute
-Clopidogrel (18.75mg/cat PO q24hrs) can be given in empty gelatin capsule due to bitter taste
+/- ACE inhibitor
-Diet low in sodium
What diet is recommended for cats with chronic heart failure
those that are low in sodium
What drug can be given in an empty gelatin capsule due to its bitter taste
Clopidogrel
In cats with CHF, you should titrate the send-home furosemide to
maintain a resting RR <30 breaths per minute
You should consider torsemide, instead of furosemide if
Consider torsemide if the furosemide dose is >6mg/kg/day PO
or if the owner can only give pills once a day
How do you treat cats with Stage D cardiomyopathy
1) Furosemide or Torsemide (if furosemide dose is >6mg/kg/day PO)
+/- spironolactone (1-2mg/kg PO q12-24h)
+/- pimobendan if systolic dysfunction present
What are possible outcomes for feline cardiomyopathies
1) CHF
2) Arrhythmias
3) Sudden death
4) Aortic thromboembolism (ATE)
What is the most important for owners to monitor at home for cats with cardiomyopthaties
Resting or sleeping respiratory rate at home
Ideally needs to be <30 breaths per min
also need to monitor for increased respiratory effort, syncope, inappetance, hiding, paresis or paralysis
How often should rechecks be for cats in Stage B1
Monitored annually
How often should rechecks be for cats in Stage B2
q6-12months
consider effect of stress on patient
maybe 3-6months
How often should rechecks be for cats in Stage C
1) CHF: 3-10 days after discharge from hospital; q2-4 months but consider effect of stress on the patient
2) ATE: 3-10 days after discharge from hospital; 2 weeks after discharge to recheck for distal limb necrosis
q1-3 montsh but consider effect of stress on patients
What diagnostics should you do for a cat with a murmur
1) NT- proBNP
2) Thoracic rads (not helpful in asymptomatic cats)
3) Echocardiogram***
4) Blood pressure **
5) Bloodwork (CBC,CHEM,UA)
What is the gold standard to diagnose cardiomyopathies
Echocardiogram
On a SNAP NT-proBNP, what would an abnormal test look like
two dark blue dots
What is the normal VHS in a cat
6.8-8.1
What might cause the heart to look bigger than it is
SQ fluids- volume overload
What is it called when the mitral valve obstructs the left ventricle’s outflow
Systolic anterior motion of the mitral valve causing dynamic left ventricular outflow obstruction
with Feline Arterial Thromboembolism, where does the thrombus orginate from
the left heart and dislodges to systemic arterial system
What are the three causes/ factors of thrombus
1) Stasis (L auricle)
2) Vessel wall injury
3) Hyper coagulability
Feline Arterial Thromboembolism typically affects
1 or more limb
Feline Arterial Thromboembolism is most commonly associated with
cardiomyopathy, although cardiac disease not present in all cats
-rarely associated with pulmonary neoplasia
What are the poor prognostic indicators associated with Feline Arterial Thromboembolism
1) Hypothermia
2) 2 or more limbs affected
3) Absence of motor function
4) Bradycardia
5) CHF
T/F: Feline Arterial Thromboembolism can present as a single forelimb
True!
What are the 5 P’s associated with Feline Arterial Thromboembolism *****
Pulselessness
Pallor
Pain
Paresis
Polar (poikilothermia / cold)
How can you diagnose Feline Arterial Thromboembolism
1) 5 P’s - pulselessness, pallor, pain, paresis, polar
2) Echo for cardiac disease
3) Lactate and glucose on affected limb
4) Lack of Doppler BP on limb
5) Increased CK (and AST/ALT)
6) Thermal camera
With Feline Arterial Thromboembolism, what do you see in terms of glucose and lactate level of affected limb
Low glucose
high lactate
What is the best thing you can do for cats with Feline Arterial Thromboembolism (Stage C) ***
1) Analgesia is priority *
-Fentanyl, hydromorphone, or methadone injections
2) Anti-thrombotic therapy
-Low molecular weight heparin (enoxaparin SQ) -BID
-Unfractionated heparin
-Oral factor Xa inhibitor (apixaban or rivaroxaban which is very expensive)
3) Anti-platelet therapy- Clopidogrel as soon as the cat can tolerate oral meds
4) Treat CHF if present
5) Sedation or anxiolytics
What drugs can you use as analgesia for cats with Feline Arterial Thromboembolism
Fentanyl *
Hydromorphone
Methadone
What are you options as anti-thrombotic therapies for cats with feline ATE
1) Low molecular weight heparin (enoxaparin SQ) *
2) Unfractionated heparin
3) Oral factor Xa inhibitor- apixaban or rivaroxaban; very expensive
What anti-thrombotic can be given SQ in patients with FATE
Enoxaparin SQ - low molecular weight heparin
What is the mechanism of Apixaban or Rivaroxaban
oral medication that is a factor Xa inhibitor (PO) used in cases of FATE as anti-thrombotic therapy
T/F: thrombolytic drug such as TPA tissue plasminogen activator is indicated in cases of FATE
F- it is controversial
not recommended by ACVIM consensus statement
Some may advocate in acute setting (<6 hours sunce event(
How can you confirm ATE
diagnostics such as cardiac POCUS or echocardiogram
What is a major complication of Feline Arterial Thromboembolism *
1) Hyperkalemia - reperfusion injury
important to monitor electrolytes and rhythm throughout hospitalization
2) Limb necrosis- requires careful monitoring
What might you see on EKG of a cat with Feline Arterial Thromboembolism
atrial standstill from hyperkalemia
-Peaked T waves
-small of indiscernible P waves
What is the prognosis of Feline Arterial Thromboembolism
1/3 -euthanized
1/3-succumb to disease
1/3- will live through the event
if severe cardiac disease, overall prognosis post-ATE is poor
Can consider 24-72h hospitalization if owners are aware of risks
Patients will be at risk for future ATE
When should you recheck patients with Feline Arterial Thromboembolism
3-10 days after discharge from hospitals
2 weeks after discharge to recheck for distal limb necrosis
q1-3 months but consider effect of stress on patient
