Diastolic Dysfunction - Primary Flashcards
(67 cards)
1
Q
What is the impact of severe acute arteriolar vasoconstriction on heart rate?
A
- Increasing your systemic vascular resistance
- Heart rate should fall dramatically because your blood pressure is increasing
- reflex bradycardia, which is what happens with dexmedetomidine
2
Q
Brain perfusion equation
A
- Systemic blood pressure - intracranial pressure
- If you have increased intracranial pressure, you will increase blood pressure to try and maintain the intracranial pressure
- If you have a dog with cerebral trauma and bradycardia, you can assume that your intracranial pressures are very high
- Cushing’s reflex
3
Q
Etiology of HCM
A
- Genetic vs idiopathic
4
Q
Breeds at risk for HCM
A
- Maine Coons
- Ragdolls
- Forest Cats
- Sphynxes
- Bengals and Birmans
5
Q
Which species gets HCM?
A
- CATS
6
Q
Genetic testing for HCM for Maine Coons and Ragdolls
A
- Myosin-binding protein C
7
Q
Physical exam findings with HCM
A
- Systolic murmur MAYBE
- Gallop sound MAYBE
- MAY BE NORMAL
8
Q
Diagnosis of HCM cats
A
- DIAGNOSIS OF EXCLUSION (like DCM)
- Echocardiogram
- Concentric hypertrophy of the LV
- Thickened left ventricular walls (free wall, septum, +/- asymmetric)
- Small LV chamber
- Thoracic rads to look for CHF
9
Q
What should normal left ventricle wall thickness be?
A
- <5.5 mm
10
Q
Which frame should you use to measure wall thickness?
A
- Diastolic
11
Q
Causes of concentric hypertrophy to rule out?
A
Causes of systemic hypertension:
- Renal disease
- Hyperadrenocorticism
- Hyperthyroidism
- Diabetes mellitus
- Medications
- Acromegaly
- Pheochromocytoma
- Hyperaldosteronism?
Other causes of stenosis
- Pulmonic stenosis
- Aortic stenosis
If a young cat with a normal or low blood pressure, probably primary HCM
12
Q
Treatment for Stage B1 HCM
A
- No treatment
- Monitoring
13
Q
Treatment for Stage B2 HCM
A
- +/- ACE inhibitor
- +/- Beta blocker
- +/- Diltiazem
- +/- Spironolactone
- +/- Antithrombotic
14
Q
Treatment for Stage C HCM with CHF
A
- Furosemide
- ACE inhibitor
- +/- Thoracocentesis
- +/- Pimobendan
- +/- Spironolactone
- +/- Antiarrhythmics
15
Q
Treatment for Stage C HCM with arterial thromboembolism
A
- SUpportive Care
- Pain management
- Antithrombotics (aspirin, clopidogrel, Low molecular weight heparin)
16
Q
Signs of left sided heart failure in cats
A
- Pulmonary edema
- Pleural effusion
17
Q
What types of effusion can happen in cats with left sided CHF?
A
- Modified transudate
- chylous effusion
18
Q
What are three differentials for chylous effusion in cats?
A
- Heart failure
- Neoplasia
- Idiopathic
19
Q
Signs of right sided heart failure in cats
A
- Abdominal effusion
- Pleural effusion
- Pretty sure that right sided heart failure is unusual in general in cats
20
Q
Pulmonary edema clinical signs
A
- Crackles
21
Q
Pleural effusion clinical signs
A
- May not hear things ventrally or have dull lung sounds ventrally
22
Q
Pulmonary edema treatment
A
- Furosemide and ACE inhibitor
- Diuretic gets rid of fluid
- ACE inhibitor to inhibit RAAS
23
Q
Pleural effusion treatment
A
- Furosemide not good at getting rid of fluid, but will slow down re-accumulation
- Thoracentesis
24
Q
Virchow’s Triad
A
- Endothelial damage
- Sluggish blood flow (Blood stasis)
- Hypercoagulability
- All of these can lead to thrombosis
25
Where does feline arterial thromboembolism usually occur?
- At the juncture of the aorta where the external iliac arteries split off
26
Clinical signs of feline arterial thromboembolism
- Paralyzed back legs
- No blood supply, so the legs are cold
- Femoral pulses weak or nonexistent
- Paw pads can become cyanotic (look at nail beds if paw pads are black)
27
Prognosis for stage B1 HCM
- fair to good
| - May take year to progress
28
Prognosis for stage B2 HCM
- Guarded
| - Will likely progress
29
Prognosis for Stage C with Heart failure
- Guarded (1-3 years with therapy)
30
Prognosis for Stage C with ATE
- Guarded to poor
31
Treatment for HCM studies
- No real studies
| - We don't know what works and c doesn't
32
What is considered Stage C for HCM cats?
- Either HCM OR arterial thromboembolism
33
Critical period for post-ATE
- First 24-72 hours
| - Concurrent CHF
34
What causes death in feline ATE?
- Reperfusion injury often due to hyperkalemia
- Potassium in the cell leaks out with necrosis from all of the cells that have died
- Once the clot breaks down and you re-establish blood flow, the potassium goes to the rest of the body
-
35
Sodium and potassium inside of the cell
- Na+: 12
| - K+: 140
36
Sodium and potassium outside of the cell
- Na+: 145
| - K+: 4
37
What causes death ultimately with hyperkalemia?
- Cardiac arrest
38
4 ECG changes that occur with yperkalemia?
1. Tented T waves
2. Decreased amplitude to no P waves
3. Increased PR interval
4. Wide QRS complexes
ULTIMATELY ATRIAL STANDSTILL
39
Atrial standstill
- Lack of P waves
- Just ventricular escape complexes
- Can lead to death ultimately
40
Treatment for hyperkalemia secondary to Feline Arterial Thromboembolism
- Dextrose +/- insulin
- Bicarbonate
- Calcium
- Furosemide
- IV fluids (BE CAREFUL)
41
Prognosis for arterial thromboembolism
- guarded to poor
- <40% survival
- HOWEVER, you CAN SAVE THESE CATS
- It's worth trying
42
Negative prognostic indicators for feline ATE
- Number of legs affected + stiffness of legs
- Low Rectal temperature affected
- If you lose blood supply to GIT; brain; renal arteries
- Other sites
43
Regain of function for feline ATE
- Can happen!
| - 3-6 months
44
Complications for feline arterial thromboembolism
- Necrosis
- Self mutilation
- Need for amputation
45
Things to monitor for cats with feline arterial thromboembolism
- Need to hospitalize for pain
| - Monitor hyperkalemia
46
Recurrence rate for feline ATE
- 25-50% on clopidogrel
47
Hypertrophic obstructive cardiomyopathy etiology
- Idiopathic
- Might be a special type of HCM?
- Papillary muscle dysplasia?
48
Who gets HOCM?
- Cats mainly
49
Diagnosis of HOCM?
- DIAGNOSIS OF EXCLUSION!
- Echocardiogram
- Systolic anterior motion of the mitral valve
- If transient with stress --> no hypertrophy
- If obstruction --> concentric hypertrophy --> HOCM
- Obstruction of the aortic outflow tract during systole (dynamic stenosis)
- Can also have mitral regurgitation too
- Thoracic radiographs (r/o CHF)
50
Treatment for Stage B1 and B2 HOCM
- Slow heart rate to reduce SAM
- Beta blocker
- Diltiazem
51
Treatment for Stage C HOCM with CHF
- Furosemide
- ACE inhibitor
- +/- slow heart rate
- +/- Thoracocentesis
- +/- Pimobendan
- +/- Spironolactone
- +/- Anti-arrhythmics
52
Treatment for Stage C HOCM with ATE
- SUpportive care
- Pain management
- Antithrombotics (Aspirin, clopidogrel, low molecular weight heparin)
- Slow heart rate (Beta blocker, diltiazem)
53
Prognosis for Stage B1 and B2 HOCM
- Guarded to good
| - Depends on response to decreased HR
54
Prognosis for Stage C HOCM with CHF
- Guarded 1-3 years
55
Prognosis for Stage C HOCM with ATE
- Guarded to poor
56
Etiology of restrictive cardiomyopathy
- Idiopathic
- AMyloidosis
- Fibrosis
57
Who gets restrictive cardiomyopathy?
- mainly cats
58
Diagnosis of restrictive cardiomyopathy
- Rule out secondary causes - DIAGNOSIS OF EXCLUSION (same list as with HCM)
- Echocardiogram
- Chest rads to check for CHF
59
Echocardiogram findings of restrictive cardiomyopathy
- Normal wall thickness (e.g. not HCM)
- Normal to reduced systolic dysfunction (e.g. not DCM)
- Diastolic dysfunction
60
Treatment for Stage B1 RCM
- No treatment
| - Monitor
61
Treatment for Stage B2 RCM
- +/- ACE inhibitor
- +/- Beta blocker
- +/- Diltiazem
- +/- Spironolactone
- +/- Antithrombotic
62
Treatment for Stage C RCM with CHF
- Furosemide
- ACE inhibitor
- +/- Thoracocentesis
- +/- Pimobendan*** (if evidence of systolic dysfunction)
- +/- Spironolactone
- +/- Anti-arrhythmics
63
Treatment for Stage C RCM with Arterial thromboembolism
- Supportive care
- Pain Management
- Antithrombotics (aspirin, clopidogrel, low molecular weight heparin)
64
Prognosis for Stage B1 RCM
- Guarded to good
| - May take years to progress
65
Prognosis for Stage B2 RCM
- Guarded
66
Prognosis for Stage C RCM with CHF
- 6-12 months?
| - Guarded; may be worse than with HCM or HOCM
67
Prognosis for Stage C RCM with Arterial thromboembolism
- Guarded to poor
