Cardio Flashcards
1
Q
Heart sound 1
A
closure of AV valves
2
Q
Heart sound 2
A
closure of the semilunar valves
3
Q
3rd heart sound
A
ventricular filling (DCM)
4
Q
4th heart sound
A
stiff ventricle (HCM)
5
Q
resting membrane potential of SA node
A
-60 mV
6
Q
Role of SA node
A
set heart rated based off intrinsic rate and input from SNS /PSNS
7
Q
Cause of spontaneous AP at SA node
A
funny Na+ channels that leak Na+ into the cell to depolarize to -40 Mv allowing L-type Ca+2 channels to open generating AP
8
Q
Role of AV node
A
slow conduction from atria to ventricles, allowing for ventricular filling
9
Q
Intrinsic rate of SA node and AV node (med size dog)
A
SA 70-80
AV 40-60
10
Q
electrical conductance through the heart
A
SA node–> AV node –> bundle branches –> purkinje fibers
11
Q
Cardiac action potential membrane potential change and cause
Phase 0
A
Rapid depolarization due to opening of voltage-gated Na+ channels
12
Q
Cardiac action potential membrane potential change and cause
Phase 1
A
Slight repolarization due to fast Na+ channels closing and potassium channels opening
13
Q
Cardiac action potential membrane potential change and cause
Phase 2
A
Plateau due to opening of Ca+2 channels
14
Q
Cardiac action potential membrane potential change and cause
Phase 3
A
repolarization due to Ca+2 channels closing and slow K+ channels opening
15
Q
Cardiac action potential membrane potential change and cause
Phase 4
A
resting potential (-80 mV) everything is closed
16
Q
What is excitation coupling in cardiac AP
A
Ca+2 activated Ca+ 2 release from sarcoplasmic reticulum
17
Q
What is an ectopic pacemaker
A
Abnormal sequence of depolarization/ contraction due to spontaneous rapid discharge outside of SA node
18
Q
K+ causes (increase/decrease) membrane potential causing what changes to HR
A
decrease, bradycardia
19
Q
Decreased calcium causes ——- conductance and —- heart rate
A
decreased
decreased
20
Q
increased temperature causes ——- heart rate
A
increases
21
Q
Preload =
A
end-diastolic pressure
22
Q
afterload pressure =
A
pressure in aorta
23
Q
Furosemide MOA
A
inhibit Na/+/K+/2Cl- cotransporter in the ascending loop of Henle to decrease Na+ and water reabsorption
24
Q
side effects of furosemide (6)
A
weakness
hypotension
azotemia
electrolyte depletion
GI upset
PU/PD
25
Enalapril / benazepril MOA
ACEi decreases angiotensin II --> decreases vasoconstriction, decreases aldosterone
26
Side effects of ACEi (4)
hypotension
azotemia
hyperkalemia
GI
27
Spironolactone MOA
aldosterone antagonist, Na+ and water excretion, K+ retention
28
Spironolactone side effects (3)
hyperkalemia
GI upset
azotemia
29
Pimobendan MOA
Ca+2 sensitizer, PDE3 inhibitor --> postive inotrope, mild vasodialation
30
Class 1 antiarrhythmic MOA and examples (4)
fast Na+ channel blocker
Procainamide, Quinidine, Lidocaine, Mexiletine
31
Side effects of class 1 antiarrhythmic (2)
GI upset
neuro signs in cats
32
Indication for class 1 antiarrhythmic
ventricular arrhythmia
33
Class 2 antiarrhythmics MOA and examples
Beta-blocker
Propanolol and atenolol
34
Side effects of class 2 antiarrhythmics (5)
bradycardia
AV block
hypotension
weakness
bronchospasm
35
Why might beta blockers worsen CHF
Beta-blockers are negative inotropes
36
Indications for beta blockers
ventricular arrhythmias
Outflow obstruction
37
Class 3 antiarrhythmics MOA and examples
K+ channel blockers
Sotalol, amiodarone
38
Side effects of sotalol (2)
Hypotension, negative inotrope
39
Side effects of amiodarone (1)
hepatotoxicity
40
indication for class 3 antiarrhythmics
ventricular and supraventricular arrhythmia
41
Class 4 antiarrhythmics MOA and examples
Ca+2 channel blocker
Diltiazem
Amlodipine
42
Indication for class 4 antiarrhythmic
SVT
43
Side effects of class 4 antiarrhythmics (5)
AV block, bradycardia, hypotension, lethargy, CHF
44
Dog with 2nd-degree AV block that responds to atropine response test, how to treat
Propantheline, Hycosamine, Theophylline/Aminophylline
45
Digoxin MOA
Na/K ATPase inhibitor
46
Digoxin side effects (3)
neuro signs, GI, arrhythmias
47
Afib treatment
Diltiazem +/- digoxin
48
SVT tx in emergency and long-term
esmolol and diltiazem
long term diltiazem sotalol
49
Why are thrombolytics controversial in tx of ATE
risk of reperfusion injury
50
What happens in reperfusion injury
acidosis, hyperkalemia, AKI
51
Preferred antiplatelet in ATE
clopidegrel
52
Negative prognostic factors ATE (3)
hypothermia
bradycardia
hypotension
53
Positive prognostic factors ATE (3)
Paresis (rather than paralysis)
1 limb only effected
early tx with anti-platelet
54
MST after ATE
1 year
55
~ ---- % of ATE patients survive to discharge
70%
56
Blood test that can support PTE
D-dimers >1000
57
Blood test to rule out PTE
D-dimers < 100
58
3 main general pathologies leading to pulmonary hypertension
- increased pulmonary blood flow (L --> R shunt)
-increased pulmonary vascular resistance
- increased pulmonary venous pressure
59
How is pulmonary pressure measured on echo
Tricuspid valve regurgitation velocity is transferred to pressure using the Bernoulli equation
Pressure = 4* v^2
60
Classify mild, moderate, and severe PH pressures
Mild 30-50 mmHg
Moderated 50-75 mmHg
severe >75 mmHg
61
Sildenafil MOA
PDE5 inhibitor --> inhibit degradation of cGMP --> promote smooth muscle relaxation via NO
62
Lack of left atrium enlargement on echo rules out ---- causes of PH
Post capillary
63
what are the 6 classifications of PH
pulmonary arterial hypertension
left heart disease
PTE
respiratory disease/hypoxia
parasitic disease
multifactorial/ unclear
64
definition of cardiac tamponade
imparment of the ventricular filling (and thus decrease CO and SV) d/t space-occupying mass/fluid in the pericardium
65
consequence of acute PCE
RA and RV diastolic collapse --> decreased CO --> decreased CO --> arterial hypotension
66
consequence of chronic PCE
SNS and RAASS activation --> R CHF
67
Definition of pulsus paradoxis
fall of systolic BP > 10 mmHg during inspiration due to a decrease in intrathoracic pressure
68
most common and second most common cause of PCE in dogs
#1 cancer
2nd idiopathic
69
EKG finding in PCE
electrical alterans
70
---% of dogs with idiopathic PCE will refuse
50%
71
MST pericardial window for idiopathic PCE
3 y
72
possible sequella of chronic PCE
constrictive pericarditis
73
In a typical PDA blood is shunted from ---- to -----
aorta to pulmonary A
74
in fetal development what is the purpose of ductus arteriosus
sunt blood from pulmonary A to aorta to bypass lungs
75
Factors that cause closure of ductus arteriosus
Change in O2 tension
decrease in prostoglandins
76
PDA dog breeds (4)
poodles little dogs GSD collies
77
PDA results in LCHF or RCHF
LCHF
78
murmur for PDA
continuous L axillary
79
the prognosis for PDA untreated
70% mortality in 1 year
80
PDA can have normal cardiac function if fix prior to
60 mo age
81
Cause of reverse PDA
PH
82
Pulmonic stenosis dog breeds
Bull dog, terriers, boxer, beagle, lab
83
Pulmonic stenosis murmur
L heart base
84
Pulmonic stenosis causes hypertrophy of left or right heart
right
85
Tx moderate to severe pulmonic stenosis
balloon dilation
86
Mild moderate and severe pulmonic stenosis
mild <50
moderate 50-100
Severe >100
87
Aortic stenosis dog breeds
newfie, boxer, GSD, golden
88
Dogs with Aortic stenosis are more at risk of ------
endocarditis
89
Aortic stenosis causes hypertrophy of left or right heart
LEVT
90
tx aortic stenosis
atenolol
91
Mild moderate severe Aortic stenosis
mild <40
moderate 40-80
severe 80
92
Most common congenital cardiac defect in cats
VSD
93
VSD causes what kind of shunting
L-->R
94
VSD murmur
Left sternal
95
aortic stenosis murmur
L base
96
ASD murmur
left
97
ASD shunt direction
L --> R
98
AV valve dysplasia dogs
Labs, GSD, danes, wiemeriner
99
components of tetralogy of fallot
VSD
overriding aorta
pulmonic stenosis
Right ventricular enlargement
100
tetralogy of fallot murmur
R sternal border
Left heart base
101
consequence of tetralogy of fallot
R --> L shunt
pulmonary hypertension
102
emergency tx of systemic hypertension
esmolol or nitroprusside
103
Tx of choice for systemic hypertension in cats
amlodipine or telmisartan
104
Tx of choice for systemic hypertension in dogs
benazepril, telmisartan, or amlodipine
105
cardiac changes with systemic hypertension (3)
concentric LV hypertrophy, aortic dilation, diastolic dysfunction
106
vascular changes with systemic hypertension (3)
arteriosclerosis, increased collagen and mucle
107
ocular changes with systemic hypertension (3)
retinal detachment/hemorrhage/edema
tortuous retinal vessels,
Optic N atrophy
108
kideny changes with systemic hypertension
glomeruloscleosis
109
CNS changes with systemic hypertension
hypertensive encephalopathy
110
5 causes of secondary systemic hypertension
Diabetes mellitus
cushings
Hyperthyroid
renal disease
adrenal tumor
111
cause of increased QRS voltage
ventricular hypertrophy
112
Cause of decreased QRS voltage
PCE / plural effusion
113
How to find MEA (the easy way)
find the tallest QRS MEA is within 30* of the positive pole of that lead
114
If the whole cardiac muscle is depolarized the EKG will be
baseline
115
BNP indicates
ventricular streach
116
Noncardiac cause of elevated BNP
renal disease
117
Elevated troponin indicates
acute cardiac myocyte damage
118
P pulmonale indicates
Right atrium enlargement
119
P mitrale indicates
left atrium enlargement
120
most affected valve layer MMVD
spongiosa
121
DCM breeds
boxer golden cocker spaniel, dobermen, giant dogs
122
DCM prognosis w/ CHF
9 weeks
123
DCM prognosis w/o CHF
2-4 y
124
pathology change in ARVC
fatty or fibrofatty infiltrate of the right ventricular myocardium
125
ARVC cause
mutation in striatin, a desmosomal protien
126
expected BNP and troponin in DCM
both elevated
127
expected BNP and troponin in ARVC
BNP normal, troponin may be elevated
128
MST ARVC
1 year (but sudden death is always possible)
129
Dogs predisposed to endocarditis
dogs with SAS
dogs with PDA
130
endocarditis dx
echo and blood cultures
131
one viral cause of myocarditis in dogs
distemper
132
4 protozoal causes of myocarditis in dogs
toxo, neospora, leishmania, chagas
133
3 bacterial causes of myocarditis in dogs
bartonella, lepto, lyme, erlichia
134
2 fungal causes of myocarditis in dogs
balsto, coccidiomycosis
135
cat breeds HCM
main coon, sphinx, bengal
136
Mutation associated with HCM in Main coons
MyBCP3
137
most common type of arrhythmia to cause cardiogenic syncope
bradyarrhythmia
138
