CV Drugs Flashcards
Watch out in using ACE inhibitors and ARBs in those with _______-kalemia.
hyper (as both cause this by counteracting the sodium-potassium exchanger in the collecting duct)
Why does hypokalemia increase risk of digoxin toxicity?
Because more digoxin binds when there is less potassium to bind (Think of the additional vending machine getting pushed up against the wall when its bananas have been depleted.)
Why are beta blockers better at treating supraventricular arrhythmias?
Because their strongest effect is in slowing AV node conduction (Think of the heart light whose bottom half is broken.)This effect can also cause heart block (think of the heart shield on Louis Heartstrong’s hat).
Long-term digoxin use can lead to what ECG finding?
“Scooped” ST segments (Think of the high schooler scooping the taSTy ice cream.)
All IA drugs can cause ___________.
torsades (think of the banner twisting across the ground floor)
Which class III drug has a lot of beta-blocking ability?
Sotalol (Think of the guy knocking over soda bottles with his beta-bugle.)
Why does prolonged QT interval cause torsades?
Because the voltage-sensitive sodium channels can fire again
What is unique about nitroprusside compared to the other nitrate drugs?
It causes equal arterial and venous dilation, whereas the other nitrates mostly cause venous dilation. (Think of the guy driving the nitro-pressure boat with equally dilated sleeves and pants.)
What is one common use of dihydropyridine blockers?
Control of hypertension in pregnant women, because they have been shown to be safe.(Think of the pregnant woman cutting an apple for the DIPpIN’ station with a large knife –the knife represents nifedipine.)
The class I anti-arrhythmics have _______ dependence.
use (because they only bind to open Na channels)
How do the dihydropyridines treat angina?
They decrease afterload and thus decrease oxygen demand. (Think of the older woman throwing off her oxygen cannula AFTER finishing her LOAD of soft serve.)
The IA drugs also ________________.
block potassium channels (just like the prom queen tossing back the banana curtains), thus prolonging the depolarization of the ventricles
Explain the action of angiotensin II on GFR.
It causes the efferent arteriole to constrict, which preserves GFR. This is important because in low-volume states, the kidneys might not have the pressure needed to filter the blood. (Think of the guy with two tense red suspenders sipping coffee from the Grounds Filter Rate machine.)
Be careful using the non-dihydropyridines in those with ______________.
heart block (represented by the heart-block shield)
Sympathetic innervation causes the AV node ______________.
conduction velocity to increase
What side effects do you need to keep in mind when administering hydralazine?
• Hypotension (woman fainting) from excess arteriolar dilation • Exacerbation of angina from reflex tachycardia (angina anvil on fire hose) –can be blocked with B1 blocker •Lupus (wolf on boat) –also remember that hydralazine is the H in SHIPP-E (the lupus-causing drugs)
Digoxin should be used in extreme caution with drugs that _______________.
can cause heart block (like beta-blockers); this is because digoxin can also cause AV nodal heart block(Think of the girl on the dance floor blocking the guy’s advances at the AV node location; also, the exit to the gym needs to remain unßlocked.)
Common side effects of digoxin include _________________.
xanthopsia (objects appearing yellow) and GI upset(Think of the guy in the dance hall about to vomit –he’s bathed in a yellow spotlight.)
Which drug is mostly non-dihydropyridine but has some vasodilatory effects?
Diltiazem (so the Dark Chocolate Diltiazem is in the middle, between Very Vanilla Verapamil and the Dairy Berry Dihydropyridines)
Digoxin should be used in extreme caution with drugs that _______________.
can cause heart block (like beta-blockers); this is because digoxin can also cause AV nodal heart block(Think of the girl on the dance floor blocking the guy’s advances at the AV node location; also, the exit to the gym needs to remain unßlocked.)
Where do the class I anti-arrhythmics act?
On the His-Purkinje system (think of the neon lights on the HP system, not the SA or AV)
Any drug that blocks __________ can cause torsades.
potassium channels (because it prolongs the QT interval)
Because digoxin stimulates vagus nerve activity, it can lead to ______________.
bradycardia from SA node slowing(Think of the Las VeGaS theme –representing increased vagal nerve tone –with John Cusack on the SA node holding a dangling heart-shaped pocket watch.)
What are the classic class IV drugs?
Verapamil (Very Vanilla ice cream)Diltiazem (Delicious Dark chocolate)
What does adenosine do to the heart?
It temporarily causes heart block, thus being an ideal drug for treating supraventricular tachycardia.
What type of calcium channels do the class IV drugs block?
L-type, also called non-dihydropyridine (think of the L-shaped handle of the Non-Dairy soft-serve dispenser)
Those with digoxin toxicity often have what symptom?
PVCs
All CCBs are contraindicated in _________________.
those with CHF(Think of how the kid with the deflated heart balloon –representing CHF –is locked out of the store.)
How does digoxin exert antiarrhythmic effects?
It directly stimulates the vagus nerve, leading to increased parasympathetic input on the SA and AV nodes –think of the “Las Vegas” sign next to DJ Foxglove.
Why should IC drugs not be used in someone with structural defects?
Because they tightly bind sodium channels and thus have the strongest effect on the phase 0 upslope
The class III antiarrhythmics uniquely share ______________.
some properties of all the categories of drugs: they block inactivated sodium channels (I), block beta-receptors (II), and block calcium channels (IV) (Think of the three singers counting off “uno dos tres cuatro!”)
What ECG finding might you see in someone taking class I anti-arrhythmics?
A widened QRS (think of the wide QRS-shaped crack in the neon sign) because the His-Purkinje fibers have been slowed and the ventricles take longer to depolarize
True or false: milrinone and nesiritide are acute agents.
True! (Think of the “Acute Issues” campaign.)
_____________ is an indicator of digitalis toxicity.
Hyperkalemia
Severe muscle weakness is a symptom of _______-kalemia.
hypo
Nitroprusside causes what adverse effect, particularly in those with renal impairment?
Cyanide poisoning (like the CN pipe pumping cyan gas in the driver’s face)
What is the mechanism of nesiritide?
It is a BNP analog, stimulating vasodilation of arteries and veins as well as diuresis of sodium. (Think of the elephant with the dilated arterial trunk and venous legs who is pouring out water onto peanuts.)
What does sympathetic innervation do to the SA node?
It increases the rate of the SA node automaticity.
The class I drugs target the _________. What effect does this have on the cardiac action potential?
Open sodium channels (think of the singer clutching the jar of peanut butter that is OPEN) This decreases the slope of the action potential (think of him leaning the microphone over, decreasing the slope of the cord’s wave), this ultimately slows the action potential through the cardiac tissue.
True or false: milrinone and nesiritide are acute agents.
True! (Think of the “Acute Issues” campaign.)
Which antiarrhythmics do not bind to potassium channels?
The IC. (Think of the untouched curtain on the 3rd floor.) As such, they do not prolong the action potential.
Dermatologically, amiodarone can _______________.
cause gray-blue discoloration in sun-exposed areas
Class IB drugs have what effect?
They have the lowest affinity for sodium channels of the class I drugs, so they don’t cause torsades or prolonged QT. Also, they don’t block potassium channels as much (think of Libby closing the potassium curtain), and thus speed up the action potential –shortening its duration. (think of Libby shutting the potassium blinds quickly).
_____________ is an indicator of digitalis toxicity.
Hyperkalemia
What is the mechanism of milrinone?
It is a phosphodiesterase inhibitor that leads to increased inotropy and arteriolar vasodilation.(Think of the politician with the cAMPaign: “one in a MILlion.” He is trying to PHOSter interest. He also has floppy dilated ears.)
What antiseizure medication has antiarrhythmic effects?
Phenytoin (it is a class IB drug –think of the friendly towing truck outside Libby’s window)
The antiarrhythmic that is also a purine interacts with what cardiac receptor?
The A1 receptor (this being adenosine) (Think of the doorway allowing only A1-level swing dancers onto the floor.)
Which arrhythmias are treatable with class III drugs?
Both supraventricular (atrial) and ventricular arrhythmias, such as atrial fibrillation (they specifically control the rhythm of atrial fibrillation)
Gingival hypertrophy is a side effect of which CCB?
Verapamil (like how the janitor is blowing a bubble with his gum)
Which three agents are recommended for first-line treatment of essential hypertension?
•Hydrochlorothiazides (kid on HIGH dive with muscular THIGHs) •Dihydropyridine calcium channel blockers (Calci-YUM ice cream machine) •ACE inhibitors (gambling Aces table near hot tub)
True or false: class IV drugs can cause increased QT interval.
False. They cause increased PR interval, because they slow conduction between the atria and ventricles.
Other than systolic heart failure, digoxin can also treat _____________.
atrial arrhythmias, because it has a greater effect on the atria
What can increase the half life of digoxin?
- Kidney failure- Antiarrhythmic drugs (Think of the overturned, kidney-shaped juke box, with the rival high schooler standing over it with a long, tapering flag. There are also records thrown over the floor –symbolizing antiarrhythmics like verapamil and amiodarone that can prevent renal clearance of digoxin.)
Because digoxin stimulates vagus nerve activity, it can lead to ______________.
bradycardia from SA node slowing(Think of the Las VeGaS theme –representing increased vagal nerve tone –with John Cusack on the SA node holding a dangling heart-shaped pocket watch.)
What kind of channel is the L-type, non-dihydropyridine calcium channel?
Voltage-gated
What is the basic function of class IV antiarrhythmics?
They, like the class II drugs, slow heart rate. Class IV drugs do so by blocking nodal calcium channels.
Arterial vasodilators decrease ________-load.
after
What is the mechanism of adenosine?
It allows more potassium to exit the cell and less calcium to enter, allowing the membrane to remain negative and suppressing AV nodal action potentials. (Think of the swing dancers on the musical NODE – in the middle of the heart – with the banana flying up and the calci-yum fallen onto the ground.)
What is the mechanism of milrinone?
It is a phosphodiesterase inhibitor that leads to increased inotropy and arteriolar vasodilation.(Think of the politician with the cAMPaign: “one in a MILlion.” He is trying to PHOSter interest. He also has floppy dilated ears.)
What agents can be given to someone with hypertensive emergency?
• IV B1 antagonists (like the bugles being blocked on the deck) • IV labetalol (like the labetalol organ) •Dihydropyridine CCBs (woman in lifeboat with Calci-Yum) •Hydralazine (HYDRo lifeboat) •Nitroprusside (NO agent that stimulates GMP like the GruMP next to the NITRO-powered boat in the background) • Fenoldopam (OLD mam PAM)
What unique problem can magnesium treat?
Torsades The mechanism is not understood. (Think of the guy moonwalking over the torn torsades banners
Two antihypertensive drugs are usually needed for patients with BPs more than ______________ above the upper recommended limit.
20/10 (Think of the life preservers: “2 recommended for more than 20 lbs.”)
Specifically, IA drugs can treat ______________.
Wolff-Parkinson-White syndrome
How does fenoldopam work?
It is a D1 agonist (like the single dope rope held by OLD lady PAM). It causes dilation of the arteries (like the dilated arm sleeves) with increased renal perfusion (represented by the spilling peanuts and kidney that she’s standing on).
What is the mechanism of digoxin?
It inhibits the Na/K pump, preventing sodium from being pumped out and potassium from being pumped in. The excess intracellular sodium then leaves the cell through increase Na/Ca exchange, thereby providing more calcium for the sarcoplasmic reticulum. (Think of the coach with peanuts, unable to leave the gym and the Calci-Yum sneaking in through the door opened by the kid sneaking out with peanuts.)
What are key clinical components of hypertensive emergency?
•BP above 180/120 (like the 180º protractor near the 12” ruler on the workstation in the boiler room) •New-onset signs of organ damage such as pulmonary edema, neurologic damage, or kidney failure (this is somewhat loosely represented by the “end-organ damage” done to the Titanic’s boiler room)
IB drugs target ___________ tissue.
ischemic/damaged (B = Broken) As such, they’re great for treating ischemia-induced arrhythmias.
What can treat digoxin overdose?
Digoxin Fab! (Just like the FABulous Las Vegas theme!)
Beta blockers cause prolonged phase __________.
4 (thereby decreasing heart rate)
Renin is produced, stored, and released from _____________.
the juxtaglomerular apparatus
What is the name of the cardiac action potential’s initial upslope?
Phase 0
List four antihypertensive agents that are safe in pregnancy.
•Alpha methyldopa (pregnant Christine in the phantom Sketch) • Nifedipine (pregnant woman cutting apple in CCB Sketch) • Labetalol (pregnant organist in beta-blocker Sketch) • Hydralazine (pregnant woman being loaded onto HYDRo rescue lifeboat in this Sketch)
Beta-blockers and ACE inhibitors decrease the ______________ after MIs.
undesired remodeling
