Cardiovascular Flashcards
1
Q
What is the function of the late I-Na?
A
maintaining plateau of action potential
2
Q
What ion antiporter can excessive inward flux of Na+ activate? What can this lead to?
A
Na+-Ca2+ Exchanger
after-depolarizations
3
Q
When is enhanced late I-Na+ found?
A
CV pathologies
4
Q
Regarding the ERP/APD, what do most anti-arrhythmics attempt to do?
A
prolong refractoriness
5
Q
Where are EADs most easily brought about?
A
Purkinje cells
6
Q
Are DADs more common during a fast heart rate or a slow heart rate?
A
fast
7
Q
Overload of what ion causes a DAD?
A
calcium
8
Q
What is the etiology of a re-entry circuit?
A
existence of conduction routes with different velocities
9
Q
What is the most common cause of re-entry tachycardia?
A
AVNRT
10
Q
Which has a higher rate, PSVT or Nodal Tachycardia?
A
PSVT
11
Q
Which two arrhythmias are associated with thrombus formation?
A
atrial fibrillation
atrial flutter
12
Q
What do class Ia drugs do to the height of Phase 2 of AP?
A
lower
13
Q
What do class Ia anti-arrhythmics do to the length of the refractory period?
A
increase
14
Q
What do class Ia anti-arrhythmics do to the slope of Phase O?
A
decrease the slope
15
Q
What ion channel do class Ia anti-arrhythmics block to prolong the AP?
A
potassium channels
16
Q
What channel do Class Ia anti-arrhythmics block at high doses?
A
calcium channels
17
Q
Which two autonomic receptors can quinidine block?
A
muscarinic and alpha
18
Q
What are the two uses of quinidine?
A
convert refractory Afib and Aflutter
19
Q
What is the most common side effect of quindine?
A
nausea and vomiting
20
Q
Can quinidine cause TdP? Why?
A
yes
blockade of potassium channels
21
Q
What cytochrome enzyme degrades quinidine?
A
CYP 3A4
22
Q
What drug inhibits CYP3A4 that can lead to the increased metabolism of quinidine?
A
cimetidine
23
Q
What three drugs can inhibit the clearance of quinidine based on their ability to increase CYP3A4?
A
phenytoin, rifampicin, phenobarbital
24
Q
Which cytochrome enzyme is quinidine a potent inhibitor of?
A
CYP2D6
25
What CV drugs toxicity is increased with co-administration of quinidine?
digoxin
26
Which has a higher likihood of causing TdP, quinidine or procainamide? Why?
quindine
procainamide doesnt block potassium channels as much
27
What are the two differences between quinidine and procainamide regarding their effects on autonomic nervous sytsem?
1. little effect on M
| 2. no effect on alpha
28
In what three conditions would the use of procainamide be contraindicated?
hypokalemia
long QT
history of TdP
29
What are the two common side effects of procainamide?
nausea and vomiting
30
What systemic reaction can be caused by procainamide?
drug induced lupus
31
What do class Ib anti-arrhythmics do to the slope of Phase O?
decrease
32
What do class Ib anti-arrhythmics do to the slope of Phase O?
decrease
33
What do class Ib anti-arrhythmics do to the action potential duration?
Ib = shortened AP duration
34
Class Ib anti-arrhythmics are effective in the Tx of two pro-arrhythmic states?
digitalis and MI
35
What type of tissue is lidocaine most effective in?
ischemic
36
Why is lidocaine ineffective in atrial tissues?
AP of atrial muscle is too short
37
Why must lidocaine be used IV?
undergoes extensive first pass metabolism
38
What is the most notable MOA of Class Ic anti-arrhythmics?
potent fast Na+ channel inhibitors
39
What part of the action potential do Class Ic anti-arrhythmics most effect?
major decrease in Phase O upslope
40
Other than the effects on sodium channels, what else can propafenone do? WHy?
β-blockade
similarity in structure to propranalol
41
Which two patient characteristics must be met in order to begin treatment with propafanone?
no/minimal heart disease
preserved Ventricular function
42
Which class of anti-arrhythmics are proven to reduce sudden death due to sudden or previous MI?
class II
43
What three ion channels can amiodarone block?
Na+
K+
Ca2+
44
What two drugs does amiodarone have structural similarity to?
thyroxine and procainamide
45
What is the main endocrine side effect of amiodarone?
"cardiac hypothyroidism"
46
Which anti-arrhythmic is highly lipid soluble?
amiodarone
47
Which anti-arrhythmic has a very high Vd?
amiodarone
48
What is amiodarone commonly metabolized to?
desethyl amiodarone
49
Why can poor amiodarone administration result in reoccurence of arrhythmias?
diffuses out of myocardium easily if all tissues are not saturated
50
What is the most common side effect of amiodarone?
interstitial pneumonitis
51
What two endocrine side effects is amiodarone most notable for causing?
hypothyroidism or hyperthyroidism
52
Which anti-arrhythmic can cause photosensitivity?
amiodarone
53
Which anti-arrhythmic can increase hepatic enzyme levels?
amiodarone
54
What are the four subunits of L-type Ca2+ channels? Which subunit contains the pores for binding of Ca2+?
α1-α2-β-γ
α1
55
What two isoforms of calcium channel do CCBs block?
L-type and T-type
56
What is the main Dihydropyridine CCB?
Nifedipine
57
What are the non-Dihydropyridine CCBs?
verapamil
diltiazem
58
Do CCBs produce vasodilation more in the arterioles or veins?
arterioles
59
What direct cardiac effect can DHP CCBs produce?
direct negative inotropy
60
Which specific cardiac disease would the use of CCBs be contraindicated in?
WPW
61
Which isoform of the adenosine receptor is activated by adenosine in the heart? What G-protein?
A1
Gi
62
What is the MOA for how adenosine effects myocardiocytes?
increased potassium efflux
63
Which isoform of the adenosine receptor is activated by adenosine in the vasculature? What ion is increased in its flux?
A2
potassium
64
What is adenosine particularly useful in the treatment of?
PSVT
65
Would acetazolamide result in an acidosis or alkalosis?
acidosis
66
Do CA Inhibitors increase or decrease intraocular pressure?
decrease
67
Where in the brain is carbonic anhydrase located?
choroid plexus
68
What two mechanisms can CAI aid in the treatment of elevation sickness?
decrease CSF production
decrease pH of CSF
69
What do CAIs do to ventilation rate?
increase
70
What do CAIs do to the pH of urine?
increase pH
71
What type of kidney stone is relatively insoluble at low pH?
calcium stone
72
CAIs can result in the loss of what ion?
potassium
73
When are CAIs contraindicated? Why?
hepatic encephalopathy
decrease urinary excretion of ammonium
74
In what two segments of the nephron would osmotic diuretics produce their effects?
proximal tubule and descending loop
75
Do osmotic diuretics expand or shrink the ECF volume?
expand
76
Where in the nephron do osmotic diuretics function?
thin limbs
77
What do loop diuretics do to calcium excretion?
increase
78
What do loop diuretics do to magnesium excretion?
increase
79
What type of diuretic is used to treat acute pulmonary edema?
loop
80
What type of diuretic is used to treat acute CHF?
loop
81
What type of diuretic is used to treat nephrotic syndrome?
loop
82
Which four ions can loop diuretics deplete?
Na, Mg, Ca and K
83
In addition to their intended action, what drug can thiazide diuretics mimmic?
CAIs
84
What can thiazide diuretics do to calcium excretion?
decrease calcium excretion
85
Most thiazide diuretics are ineffective when the GFR is between which two levels?
30-40 ml/min
86
What CNS effects can loop diuretics induce?
ototoxicity
87
Why can thiazides be useful in the treatment of calcium nephrolithiasis?
thiazides decrease calcium excretion
88
Which class of diuretics can be used to treat diabetis insipidus?
nephrogenic
89
Can thiazides produce hypokalemia or hyperkalemia?
hypokalemia
90
Can thiazides produce an increase or decrease in levels of uric acid?
increase
91
What can thiazides do to glucose metabolism? Why?
impaired glucose metabolism
thiazides decrease pancreatic insulin production
92
What do thiazides do to lipid levels?
increase lipid levels
93
Thiazides can produce an allergic reaction in patients who are also allergic to what other type of drug?
sulfonamides
94
How strong is amiloride as a single use diuretic?
quite weak
95
Amiloride spares which ion?
potassium
96
Which ion can amiloride cause an increase in?
potassium
97
Amiloride is contraindicated in patients with what two conditions?
hyperkalemia
propensity to develop hyperkalemia
98
What does amiloride do to glucose profile?
glucose tolerance
99
What type of inflammation can amiloride produce?
interstitial nephritis
100
Can amiloride produce renal stones?
yes
101
What two drugs does spironolactone have to be used in combination with to reduce LV modeling?
ACE or ARB
102
Spironolactone increases the bioavailability of what substance?
nitrous oxide
103
What electrolyte defect can spironolactone produce?
hyperkalemia
104
Which drug can produce metabolic acidosis in cirrhotic patients?
spironolactone
105
What is the systolic and diastolic criteria for a HTN urgency? Is end organ damage present during hypertensive urgency?
systolic greater than 180
diastolic greater than 120
no
106
Resistant HTN is defined by what?
HTN than cannot be controlled by three or more drugs one of which is a diuretic
107
What blood pressure does a physician work to attain in a patient with diabetes or CKD?
less than 130/80
108
Sulfhydrl containing ACE inhibitors are structurally related to what drug?
captopril
109
Dicarboxyl containing ACE inhibitors are structurally related to what drug?
enalapril
110
Phosphorus containing ACE inhibitors are structurally related to what drug?
Fosinopril
111
What type of anti-HTN drug is used in good combination with ACE inhibitors?
ACEI and diuretics
112
Which anti-HTN meication is contraindicated in pregnancy?
ACE Inhibitors
113
Which population group generally responds poorly to ACE Inhibitors?
Elderly african americans
114
What are the only two CCBs that can be used during LV failure?
amlodipine and felodipine
115
Which anti-HTN medication can be used to treat Reynaud syndrome?
CCBs
116
Which anti-HTN medication is particularly useful during cyclosporin induced HTN?
CCBs
117
In a patient without a sulfa allergy, what situation would the use of a thiazide diuretic be contraindicated?
gout
118
Which endocrine disorder could β-blockers be used to treat?
Hyperthyroidism
119
In what situation is the use of α-methyldopa almost always used?
gestational HTN
120
Which anti-HTN can prouce a positive coombs test?
α-methyldopa
121
What are the MOAs of hydralazine?
decreases SR Ca2+ release
opens Ca2+ potassium channels in smooth muscle
122
Does hydralazine primarily effects arteries or veins?
arteries
123
In what two situations is hydralazine often used?
gestational HTN and resistant HTN
124
What can long term use of hydralazine result in?
drug induced lupus
125
What two compensatory rxs can the use of hydralazine induce?
tachycardia and sodium retention
126
What two drugs should hydralazine always be used in combination with?
β-blocker and/or NDHP CCB
diuretic
127
What is the MOA of minoxidil?
opens ATP sensitive potassium channels
128
Does minoxidil effect veins or arteries?
arteries
129
What two drugs is minoxidil often used in combination with?
β-blocker
diuretic
130
What is the MOA of nitroprusside?
donates nitrous oxide
131
What are the two side effects of nitroprusside?
methemoglobinemia
cyanide poisoning
132
What is direct renin inhibitor?
Aliskiren
133
What electrolyte disturbance can Aliskerin?
hyperkalemia
134
When is Aliskerin contraindicated?
pregnancy
135
Though not commonly used, reserpine can be used in conjugation with what anti-HTN drug?
thiazide diuretic
136
What are the preferred diuretics for HTN? Which specific diuretic?
thiazide
chlorthalidone
137
What is the preferred α1-antagonist?
Daxozosin
138
What is the preferred ENaC antagonist?
Amiloride
139
What are the two classical mediators of anginal chest pain?
bradykinin and adenosine
140
What are the three nitrates used to treat angina?
nitroglycerin
isosorbide dinitrate
isosorbide mononitrate
141
What organelle processes nitrates? What enzyme? What enzymatic process?
mitochondria
aldehyde reductase
denitrifiction
142
What second messenger does cGMP activate?
cGK-1
143
What are the three actions of cGK-1 hat lead to vasodilation?
increase Ca2+ efflux
increase SR Ca2+ uptake
phosphorylate MLCK
144
What is the one draw back of nitrates?
complete tolerance develops quickly
145
What is the standard nitrate dosing regimen in use today?
allow for several hours of nitrate free plasma every day
146
What are the two dosing routes for nitroglycerin?
sublingual
transdermal
147
What is the half life of nitroglycerin?
1-4 minutes
148
What is the half-life of isosorbide dinitrate?
40 minutes
149
Which nitrate is completely bioavailable?
isosorbide mononitrate
150
Are nitrates more effective in veins or arteries?
veins
151
Does isosorbide have any effect on vascular resistance?
no
152
What nitrate can dilate the epicardial coronary vessels?
isosorbide mononitrate
153
What ion channel can Ia AAs block?
calcium
154
Which two autonomic receptors can quinidine block?
alpha and M
155
According to the FDA, what are the two uses of quinidine?
refractory pt's with afib or flutter
156
What are the two potentially lethal side effects of quinidine? Why?
tachycardia (alpha)
TdP (prolonging QT)
157
Which AA can cause tinnitus?
quinidine
158
What ion channel can quinidine block at therapeutic doses? What ryhthm could this produce?
potassium
TdP
159
What two channels does procainamide block?
sodium and potassium
160
What is the ventricular sole use of procainamide?
Tx of life-threatening ventricular arryhthmias
161
What are the three supravetricular uses of Procainamide?
Reentrant SVT
Afib
Aflutter (with WPW)
162
Can procainamide cause TdP? Why?
yes
prolong QT due to K+ block
163
Which anti-arrhythmic drug can cause lupus-like symptoms?
Procainamide
164
What does lidocaine do to Vmax?
inhibit
165
Does lidocaine shorten or prolong cardiac AP? Why?
shorten
blocks late Na+ channels
166
Which sodium channels does lidocaine block?
open and inactivated sodium channels
167
Why is lidocaine more effective in ischemic tissue? Why?
shortens cardiac AP
ischemia usually leads to longer APs and induces arrhythmias
168
Behind amiodarone, what is the most preferred AA?
lidocaine
169
Is lidocaine useful for post-MI arrhythmias?
no
170
Why is lidocaine only used IV?
extensive first pass hepatic metaolism
171
Of the Class I AAs, which inhibit sodium current the most? What does this do to QRS duration?
Ic
long QRS duration
172
Propafenone is used to treat which two type of tachycardias? In what two types of patient?
atrial and ventricular arrhythmias
minimal/no heart disease and preserved ventricular function
173
Can propafenone be used in patients with previous MI?
no
174
Which AA are not particularly effective during ventricular tachycardias (not IV)?
beta-blockers
175
Amiodarone blocks what three ion channels?
sodium, calcium and potassium
176
What three autonomic receptors can amiodarone block?
alpha, beta and muscarinic
177
What drug is replacing lidocaine for the Tx of VT and VF?
amiodarone
178
Where is amiodarone initially highly concentrated? Do other tissues follow this?
myocardium
no
179
Which AA has poor plasma saturation?
amiodarone
180
What is the toxicity of amiodarone?
lethal interstitial pneumonitis
181
What are the two side effects of verapamil?
constipation
exacerbate CHF
182
What are the two contraindications of verapamil?
Afib with WPW
V-tach
183
What does adenosine do to the APD of atrial cells?
decrease
184
What is produced when adenosine activates A2 receptors?
nitrous oxide
185
Why can adenosine cause someone to stop breathing?
stimulates pulmonary stretch receptors
186
What type of arrhythmia is treated with adenosine?
AVNRT
187
What are the two mechanisms by which β-adrenergic stimulation of myocytes can lead to an increased calcium influx?
L-type
Calcium induced calcium entry
188
Would digoxin lead to higher or lower EDV?
lower
189
What does digoxin do to QT interval?
shorten
190
What does digoxin do to pulmonary and venous systemic pressure?
decrease
191
Which electrolyte disturbance is particularly harmful if administering digoxin?
hypokalemia
192
What organ primarily effects digoxin clearance?
kidney
193
What bacterium can inactivate Digoxin?
eucobacterium lentum
194
Which two classes of anti-arrhythmics can produce harmful side effects in patients taking digoxin?
Ia and IV
195
What GI drug can interfere with digoxin?
cimetidine
196
Which electrolyte can digoxin deplete?
potassium
197
Does digoxin improve mortality?
no
198
What are the two cardiac PDE inhibitors?
Milrinone and Inamrinone
199
How are most ACE Inhibitors cleared? In what patient population must one most pay careful attention to their dosages?
kidneys
renal failure
200
The activity of which ion channel is enhanced in ischemic heart disease? Increases in the intracellular concentrations of what other ion can this lead to ?
Late sodium
calcium
201
What would an increase in intracellular calcium mediated by late sodium currents do to diastolic tension?
increase
202
Do class Ia Anti-arrhythmics have high, medium or low blockade of Na+ channels?
medium
203
What other two ion channels can Class Ia block?
potassium and calcium
204
What are the two most common side-effects of quinidine?
diarrhea and tinnitus
205
What are the two most common side effects of procainamide?
nausea and vomiting
206
What are the only arrhythmias that Class II AA's are effective in treating?
supraventricular due to excess sympathetic stimulation
207
What autonomic receptors can amiodarone block?
α, β, M
208
Which has a higher anti-arrhythmic potential, amiodarone or desethyl amiodarone?
desethyl amiodarone
209
Are CCBs more effective in veins or arteries?
arteries
210
Which adenosine receptors are found in SA and AV node? What ion channel is affected?
A1
opens potassium channels
211
Which adenosine receptors are found on endothelial cells? What ion channel is opened up? What ion is increased intracellularly? What does this lead to?
A2
K+
Ca2+
vasodilation
212
Do CAIs produce a metabolic acidosis or alkalosis? What does this do to urine pH?
metabolic acidosis
increase urine pH
213
What are the three uses for acetazolamide?
glaucoma
altitude sickness
urine alkalinization
214
When is the use of acetazalamide contraindicated?
liver failure
acetazolamide increase ammonium levels
215
What is the main clinical use of osmotic diuretics?
acute renal failure
216
What type of diuretic is used to treat cerebral edema?
osmotic diuretic
217
What metabolite can loop diuretics decrease the excretion of?
uric acid
218
Why can thiazides cause vasorelaxation?
activate Ca2+ dependent K+ channels
219
Should the dosage of ACEI's be increased or decreased in pt's with high renin levels?
reduced
220
Regarding CCBs, what heart dysfunction would render these drugs contraindicated?
reduced LV volume
221
What drug in this section would proposed to treat migraines?
verapamil
222
Which anti-hypertensive would be good for a patient with osteoporosis?
thiazides
223
Which anti-HTN can cause rebound HTN?
clonidine
224
In what situation is aldomet particularly used/
gestational HTN
225
Which anti-HTN cause cause a positive direct coombs test?
Methyldopa
226
Does hydralazine effect veins or arteries more?
arteries
227
In what disease would hydralazine be particularly useful?
chronic renal disease
228
What two drugs should hydralazine always be used with?
beta-blocker
diuretic
229
What two drugs should minoxidil always be used with?
beta-blocker
diuretic
230
What is the only clinical use of minoxidil?
severe refractory HTN
231
How is sodium nitroprusside administered?
IV
232
Does sodium nitroprusside decrease preload, afterload or both?
both
233
Reserpine in use with what other drug has been shown to be most effective?
thiazide
234
What is the best thiazide diuretic in the opinion of HTN experts?
Chlorthalidone
235
What three variables can produce an EAD?
slow HR
hypokalemia
prolonged APD
236
Would TdP be triggered by an EAD or DAD? Why?
EAD
premature beat arriving at delayed APD
237
Does propafenone effect the QT?
no
238
Do class IV AAs decrease myocardial contractility?
yes
239
Which exchanger in the PCT initiates the reabsorption of NaHCO3?
Na+/H+ Exchanger
240
What kind of renal disease can mannitol inhibit the effects of?
acute tubular necrosis
241
Which diuretic can produce venodilation?
Furosemide
242
Aldosterone prevents the loss of which two ions ?
potssium and magnesium
243
In what three situations would ACEIs be contraindicated?
pregnancy
bilateral renal artery stenosis
History of angioedema
244
What cardiovascular drug could produce a favorable response in Reynaud Syndrome?
CCBs
245
What cardiovascular drug could produce a favorable response in Migraine?
CCBs
246
Other than anti-HTN effects, what type of positive effects could alpha blockers produce?
better lipid profile
247
Do nitrates effect coronary resistance? What does this avoid?
no
coronary steal
248
What is the most common side effect of nitrates?
headache
249
Which prolongs the QT segment more, quinidine or procainamide?
quinidine
250
What marks a hypertensive urgency?
end organ damage
251
Who are the poor responders to ACEIs?
older, AAs
252
Who are the good responders to ACEIs?
caucasian
253
When should the use of DCCBs be avoided?
LV failure
254
Thiazides are front line treatment in patients with what two previous pathological happenings?
isolated LV dysfunction
ischemic stroke
255
Clonidine should be prescribed with what other medication?
diuretic
256
What is the most notable side-effect of minoxidil therapy?
rebound contractility
257
Which anti-HTN can increase PANS symptoms?
reserpine
258
What is the beta-blocker of choice for gestational HTN?
labetalol
259
What is the CCB of choice for gestational HTN?
nifedipine
260
How long does stable angina last?
2-10 minutes
261
How long does unstable angina last?
less than 20 minutes
262
What is the 1/2 like of GTN?
1-4 minutes
263
What is the 1/2 like of Isosorbide Dinitrate?
1-40 minutes
264
What is the 1/2 like of Isosorbide Mononitrates?
2-4 hours
265
Do nitrates effect preload or afterload?
preload
no effect on afterload
266
What coronary vessels do nitrates dilate? Which ones specifically?
epicardial
coronary vessel stenoses
267
Which two nitrates can be used prophylactically?
GTN and ISDN
268
What is the long-acting nitrate?
ISMN
269
Which nitrate and anti-HTN are a good combination for AAs with CHF?
ISDN and hydralazine
270
Which two nitrates can cause hypotension?
GTN and Isosorbide Dinitrate
271
What is the Class I anti-arrhythmic that does not block any autonomic receptors?
procainamide
272
What two types of arrhythmias is lidocaine used for?
acute MI
digoxin induced
273
What two types of sodium channels does lidocaine block?
open
inactivated
274
What are the two main uses for control of arrhythmias using NDCCBs?
SVT
rate control of Afib
275
In what patient group are osmotic diuretics not used? Why?
heart failure
expansion of ECV would be hard for heart to pump against
276
Which diuretic is less effective in patients with reduced renal function?
thiazide
277
What is the systolic for stage 1 HTN? Diastolic?
systolic = 140-159
diastolic = 90-99
278
In what two situations are ARBs contraindicated?
pregnancy
BLRAS
279
When are DHP-CCBs contraindicated?
poor LV function
280
What drug is particularly useful in elderly patients with isolated systolic HTN?
CCBs
281
What drug can be used as an alternative to beta-blockers in CAD?
NDHP-CCBs
282
Do nitrates decrease preload or afterload?
preload
283
What is bowditch relationship?
fast rate promotes contractility
284
What is anrep relationship?
increasing afterload increases contractiltiy
285
What does digoxin do to coronary blood flow?
increase
286
What is the T1/2 of digoxin? How long does it take digoxin to reach steady state?
36-48 hours
7 days
287
What are the three most common side effects of digoxin?
nausea, vomiting, anorexia
288
Digoxin is often given to HF patients with what other abnormality?
afib
289
What two drugs are used to clear digoxin?
Digibind
cholestyramine
290
What are the three CV effects of PDE III inhibitors?
increase contractility
increase relaxation
decrease arterial pressure
291
What is the main diffence between digoxin and milrinone?
milrinone is used acutely only
292
What AA can produce photosensitivity and corneal microdeposits?
amiodarone
293
Does minoxidil increase or decrease CO?
increase
294
What does minoxidil do to renal blood flow?
increase
295
What is the main negative side effect of aliskiren?
hyperkalemia
296
What does digoxin do to RBF?
increase RBF
297
What do PDE III inhibitors do to MAP?
decrease MAP
