Arrhythmias Flashcards
(23 cards)
- What is an arrhythmia?
- what are some signs and sx’s?
- Whats used to diagnose an arrhythmia?
- Whats an ambulatory ECG device that records electrical activity of the heart continuously for 24-48 hrs?
- What can this device detect?
- an abnormal heart rhythm which can cause the heart to beat too slow (bradycardia) or too fast (tachycardia)
- dizziness, shortness of breath, fatigue
- ECG
- Holter monitor
- intermittent arrhythmias
- Where do electrical impulses begin?
- This region is known as the heart’s ____?
- Whats a normal HR?
- When does electrical conduction slow down?
- Then, the impulse continues through the ___ and into the ventricles
- What does the bundle of his divide into?
- The signal will continue to spread through the ventricles via the ___
- SA node
- natural pacemaker
- 60-100 BPM
- When the signal reaches the AV node
- bundle of his
- right bundle branch (right ventricle), left bundle branch (left ventricle)
- Purkinje fibers
- What does the cardiac action potential refer to?
- action potential provides the __ needed to power the cardiac conduction pathway
- cells in SA node have ___ which means?
- movement of ions through channels in myocytes that cause electrical impulses in the cardiac conduction pathway
- electricity
- automaticity
-they initiate their own action potential
Electrical Signaling Phases:
- Phase 0: a heartbeat is initiated when ___ occurs in response to an influx of __; this causes ___
phase 1: early rapid repolarization (Na channels close)
- Phase 2: plateau in response to an influx of and efflux of?
- Phase 3: What occurs? (talk about ion and what happens to ventricles)
Phase 4: resting membrane potential established; atrial depol occurs
- rapid ventricular depolarization, sodium , ventricular contraction
- Influx of Ca and efflux of K
- rapid ventricular repolarization due to efflux of K; causes ventric relaxation
- Whats the most common cause of arrhythmias?
- What are some non cardiac conditions that can trigger or predispose a pt to an arrhythmia?
- What r the 2 categorizations of arrhythmias?
- Supraventric Arrhythmias: Name the most common
- Ventricular Arrhythmias: Name the most common and another known name for it
- what can this type of arrhythmia be related to?
- Myocardial ischemia or infarction
- electrolyte imbalances, (especially K, Mg, Na, and Ca)
-elevated sympathetic states (hyperthyroidism, infection) + drugs (illicit ones that prolong the qt interval) - Supraventricular and ventricular
- AFib
- Premature Ventricular COntractions (PVCs); also called skipped heartbeats
-Stress or too much caffeine
- What is a Ventricular Tachycardia?
- Pulseless VT is a ___ and ___ should be initiated whereas VT w/pulse can be treated with medications
- All untreated VT can degenerate into ___ which is also a __
- series of PVCs that result in a heart rate > 100 BPM
- medical emergency, ACLS (advanced cardiac life support)
- ventricular fibrillation , medical emergency
- when is a QT interval considered prolonged?
-but more worrisome when its markedly prolonged like? - prolongation of QT interval is a risk factor for?
-which is a particularly lethal ventric tachyarrhythmia that can cause ___
- > 440-460 msec
- > 500 msec - TdP
-sudden cardiac death
The risk of drug induced QT prolongation incr with:
H
M
Reduced ___ or ___
Electrolyte abnorms like (3)?
Other cardiac conditions like ? (2)
higher doses
multiple qt prolonging drugs taken at same time
drug clearance, drug interactions
hypokalemia, hypomagnesemia, hypocalcemia
bradycardia or HF
- Prior to starting any drug for a non life threatening arrhythmia, what should be checked to identify any potentially reversible causes?
- All antiarrhythmic drugs have the potential to induce ____
- Risk of additive proarrhythmia can be minimized by?
- electrolytes + toxicology screen
- proarrhythmia (causing a new one for worsening the existing one)
- correcting electrolyte abnorms
AMIODARONE Class 3:
- What class?
- What does it do?
- Notable for a ?
- Chemical structure containing ___ which impacts ____
- This is the preferred antiarrhythmic in?
Specifics:
- Whats the brand name?
- Boxed warnings for? (3)
- COntraindications? (1)
- 4 major warnings?
- Side effects? (3)
- Monitoring for? (6)
- For IV infusions > 2 hrs, it requires a ___
- pre mixed IV bags like Nexterone comes in a ___
- use a ___ filter; ___ line is preferable
- Incompatible with __
- class 3
- k channel blocker that also blocks Na and Ca channels and alpha and beta adrenergic receptors
- very long half life of 40-60 days
- iodine, thyroid function
- Heart failure
- Nexterone or Pacerone
- pulm toxicity, hepatotoxicity
-should be used for life threatening arrhythmias ONLY due to it being PROARRHYTHMIC - Iodine hypersensitivity
- -Hyper/Hypo thyroidism (hypo more common)
-optic neuropathy or corneal microdeposits
-photosensitivity (blue grey skin discoloration)
-Peripheral neuropathy - hypotension, bradycardia (may require decr infusion rate), photosensitivity!
- ECG, BP, HR, electrolytes, LFTS q6months, thyroid functions (TSH and free T4) every 3-6 months
- non PVC container (polyolefin or glass)
- non PVC, non DEHP galaxy plastic container
- 0.22 micron filter; central line
- heparin (flush line with saline)
AMIO DDI’s:
- Amio can incr the level of many other drugs; it’s a weak inhib of ? (4)
- When starting amio you need to decr digoxin by how much? warfarin?
-whats the max dose of simvastatin and lovastatin when on amiodarone? - Additive effects can occur when used with other drugs that decr HR such as? (4)
- What drug should you avoid/not use together with Amiodarone and why?
- CYP 2C9, 2D6, 3A4, PGP
- Digoxin decr by 50%
warfarin decr by 30-50%
Simva: 20 mg/day
Lova: 40 mg/day - non dhp CCBs, digoxin, beta blockers, clonidine
- Sofosbuvir due to enhanced bradycardic effect
Class 1A:
- Disopyramide
-Warnings? (2)
-Side effects (1) - Quinidine
a. How should you take it and why?
b. Warnings (3) ?
c. Side effects (4)
d. what are the symptoms of quinidine toxicity or cinchonism? - Procainamide
a. formulation?
b. It has an active metabolite … whats the name and how is it cleared?
c. therapeutic levels of procainamide?
d. BBW for? (3)
e. Warning for being __
f. How is procainamide metabolized to NAPA? who is at risk for toxicity?
- Warnings: Proarrhythmic, myesthenia gravis due to ANTICHOLINERGIC effects
Side effects: Anticholinergic effects like (dry mouth, constipation, urinary retention)
2a. Take with food/milk to decr GI upset
2b. Proarrhythmic, hemolysis risk (AVOID IN G6PD deficiency) , can cause positive COOMBS test
2c. DILE, diarrhea, stomach cramping , cinchonism
2d. tinnitus, hearing loss, blurred vision, HA, delirium
3a. injection
b. N acetyl procainamide or NAPA; renally cleared
c. 4-10 mcg/mL
d. Potentially fatal agranulocytosis; long term use leading to antinuclear antibody (ANA) ; which can result in DILE!
e. proarrhythmic
f. acetylation; slow acetylators
Class Ib Drugs: Lidocaine + Mexiletine
- They’re useful for ___ only… NO EFFICACY IN AF
- Lidocaine How supplied?
- IV Lidocaine is specifically used for? (2)
- ventricular arrhythmias
- injection
- refractory VT/cardiac arrest
Class 1C Drugs:
- Flecainide
a. boxed warning?
b. Contraindications? - Propafenone
a. Contraindications?
b. Warnings for ?
c. side effects? (1)
1a. Proarrhythmic effects especially in AF
1b. Structural heart disease like HF or MI !
2a. Structural Heart disease like HF or MI!
2b. Proarrhythmic
2c. taste disturbances (metallic)
Class 3 Drugs:
- Dronedarone
a. BBW?
b. Contraindications?
C. Warnings? (2)
d. side effects? (1)
e. Unlike amio, doesnt contain iodine so has little effect on?
f. Avoid use with strong inhibs and inducers of ___ and with drugs that ___
1a. CI in pt’s with decomp HF (NYHA class 4 or any NYHA class w/recent hospitalization due to HF)
or
Permanent AF due to incr risk of death, stroke, and HF
1b. Strong CYP3A4 inhibs and qt prolonging drugs
1c. Hepatic failure and pulmonary toxicity
1d. proarrhythmic
1e. thyroid function
1f. CYP 3A4, prolong qt interval
Class 3 Drugs:
- Dofetilide
a. Boxed warning? (3)
b. A preferred antiarrhythmic in? - Sotalol
a. what CrCL must you decr the dosing frequency in?
b. Boxed warnings? (2)
c. Warnings (2)
d. main side effect?
e. It is a ____ beta blocker and K channel blocker - Ibutilide
a. how supplied?
1a. Must be initiated (or reinitated) in a setting w/continuous ECG monitoring
-Experienced staff and ability to assess CrCL for a min of 3 days
-Proarrhythmic (qt prolongation)
1b. HF
2a. CrCL < 60
2b. Adjust dosing interval based on CrCL to decr risk of proarrhythmia
-qt prolongation directly related to SOTALOL CONCENTRATIONS
2c. Proarrhythmic, can worsen HF and cause BRONCHOCONSTRICTION
2d. bradycardia
2e. NON SELECTIVE
3a. injection
ADENOSINE:
- How is it supplied?
- How does it work?
- Half life?
- whats it used for?
- injection
- activates adenosine receptors to decr AV node conduction
- < 10 seconds
- Used for supraventricular re entrant tachycardias !!!
- AFib Occurs when multiple waves of electrical impulses in the atria result in an ____
- The rapid ventricular rate can ___
- If AF is paroxysmal, whats the definition?
- If AF is persistent what is the definition?
- If it is PERMANENT AF, what does this mean?
- Why might pt’s with AF require anticoagulation?
- irregular and usually rapid ventricular response
- decr cardiac output
- intermittent AF that terminates within 7 days of onset
- continuous AF sustained for > 7 days
- No further attempts at rhythm control
- blood can become stagnant in atria which incr clot formation and can cause stroke if it breaks off
RATE CONTROL:
- Goal resting HR is__ for pt’s with symptomatic AF
- Whats a more lenient goal for asymptomatic pt’s that have preserved LVF?
- Whats recc for controlling ventricular rate in pt’s with AF? (2)
- However, if a pt has HFrEF, what shouldnt they receive?
- What can be added for refractory patients or pt’s who cant tolerate the BP lowering effects of bb and non dhp ccbs ?
- <80 BPM
- < 110 BPM
- Beta blockers + Non DHP CCBS
- Non DHP CCBS
- Digoxin
Rhythm Control:
- WHich drugs /methods are used for rhythm control?
- for permanent AF, what should you avoid?
STroke PPX:
- Whats preferred for non valvular AF?
- WHen is warfarin indicated ?
- Class 1A, 1C or 3 or electrical cardioversion
- a rhythm control strategy w/antiarrhythmic drugs
- DOACs
- in patients with AF AND a mechanical heart valve
DIGOXIN:
- whats its MOA? what does it cause, exert, enhance, and result in ?
- WHats DIgoxins brand name?
- typical dose?
- What should you do if CrCL< 60?
- What should you do when converting from oral to IV ?
- Whats the therapeutic range for AFib? (NOT HF)
- What should be monitored for digoxin?
- Sx’s of Digoxin toxicity? (6)
- What is this risk incr with? (3)
- Its usually given in combo with a __ or ___ for rate control (not usually given alone)
- antidote?
- Inhibits the Na-K-ATPase pump
causing: positive inotropic effect
exert: parasympathetic effect
enhances: vagal tone
results in: reduced HR ( negative chronotropy)
- Digitek, lanoxin
- 0.125 mg - 0.25 mg daily
- decr dose or decr frequency
- decr dose by 20-25%
- 0.8-2 ng/mL
- Electrolytes, renal function, HR
- N/V, loss of appetite, blurred/double vision, greenish/yellow halos, bradycardia, life threatening arrhythmias
- hypok, hypomag, hypercalcemia
- b blocker, non dhp ccb
- digifab
Digoxin DDI’s:
- Its a substrate of ___ and __ (minor)
- What happens to levels with pgp inhibitors? and what r some of these inhibitors?
- What should you do to digoxin dose with amio or dronedarone?
- PGP, CYP 3A4
- levels incr with pgp inhibs
-amio, dilt, verap - decr digoxin dose by 50%
Cardioversion carries a risk of?
What is usually required before and after successful cardioversion?
thromboembolism
anticoag
