Exam 3 - SVT Flashcards
What is the drug of choice for abolishing Acute SVT?
Adenosine
If AF PT is hemodynamically stable vs unstable what changes in the short-term goals?
Stable=Go with anticoagulation second
Unstable=Go with rhythm second
Newly discovered persistent AF is treated in what 4 steps?
- Rate control and anticoagulation as needed
- Antiarrythmic drug therapy
- Cardioversion
- Long-term antiarrythmic drug therapy
What med types are used for pharmacological rate control in AF?
Beta-blockers, CCB, Digitalis, Amiodarone, Dronedarone.
What two things used for non-pharmacological rate control?
- Pacing
2. Ablation
What two drugs are preferred for chemical cardioversion?
- Dofetilide
2. Ibutilide
Which three drug types prevent remodeling in AF?
- ACEI
- ARB
- CCB
Which Nonselective/Cardioselective/Mixed Beta-Blockers are used for rate control in AF?
Cardioselective: Atenolol, Metoprolol Succ and Tart
Nonselective: Propanolol, Nadolol
Mixed: Carvedilol, Labetolol
Which CCBs are used for rate control in AF?
Non-DI CCBs (Verapamil, Diltiazem)
Two cases where rate control is very important in AF?
- LV damage
2. Extensive CAD
What are some problems with Antiarrythmic drugs?
Limited efficacy long-term (recurrence likely), adverse drug reactions (may cause arrythmias)
Are Class I drugs used (QPDLFP)? Why or why not?
Very rarely. Old and dangerous; can cause arrythmias.
What percent with AF of people will fall out of NSR due to disease progress? What about those on Amiodarone?
50% will fall out due to disease progression. Amiodarone 2/3 will stay in NSR.
In a PT with persistent or paryoxysmal AF what is the first question to ask with regards to drug selection?
Is there structural heart disease or not
In PTs with AF and no structural heart disease what is the progression of drugs and other therapies?
D.D.F.P.S.->Amiodarone->Catheter Ablation
Dofetilidide, Dronedarone, Flecainide, Propafenone, Sotolol
When is Amiodarone used in AF? What can it cause?
Used for those who have failed previous therapy. Can crash CO.
If AF PT has structural heart disease what must you next determine?
If they have CAD or HF
If AF PT has CAD with structural heart disease what are treatment options
DDS->Amiodarine->Ablation
If AF PT has Heart Failure with structural heart disease what are treatment options?
Amiodarine or Dofetilides->Ablation
Which ion is blocked in the Class 1 drugs? What are the 6 Class 1 antiarrythmics?
Sodium
QPDLFP
What ions blocked in Class I, II, III, and VI
I=Na+
II=Ca++
III=K+
IV=Ca++
What ion is blocked in Class II drugs? What are they?
Calcium.
Beta-blockers.
What ion is blocked in Class III drugs? What are the 5?
Potassium
SAD.ID
Which ion is blocked in Class IV drugs? What are the two?
Calcium.
Verapamil and Diltiazem.
Three are three short-term treatment goals for AF patients if hemodynamically stable or unstable?
- Immediate rate control
- Drug or electrical cardioversion
- Anticoagulation
If hemodynamically stable then anticoagulation is number 2.
What are the three long-term goals for AF patients?
- Rate Control
- Maintenance of Sinus Rhythm
- Stroke Prevention
Which ions are blocked in sinus rhythm maintenance meds in AF?
Sodium=Class IA and Ic
Potassium=Class III
Calcium=Beta-Blockers
Three category of meds which prevent remodeling in AF?
- ACE-I
- ARC
- CCBs
What is the most common arrythmia world wide? What percent of them are over 65 y/o? How many times is their cardiac mortality and stroke risk increased?
AFib is most common. 80% over 65 y/o. 2x cardiac mortality, 5x stroke risk.
Class I VW drugs all block what Ion?
Sodium
What are the Class II VW drugs, mechanism, and which ion? Effect on action potention time, AV node, and conduction in ischemic tissue?
Beta-Blockers block calcium. Decreased beta-adrenergic sympathetic activity, prolonged action potential, slower conduction in ischemic tissue. Slots heart-rate, slows AV nodal conduction, and AV nodal refractoriness.
Metroprolol MOA? Labeled and unlabeled uses?
CYP2D6 extensive 1st pass. Selective B1. Used when rate control immediately needed.
Unlabeled: Tachyrhythmias, Acute VT
Carvedilol MOA? Labeled use? Unlabeled use?
Combo non-selective Beta-adrenergic and Alpha-adrenergic blocking activity. Based on dose.
Labeled use: HTN, angina, post-MI LVD and HF
Unlabeled: Rate mgm’t in select AF patients (post-MI, stable LVD, and HF)
Sotolol MOA? Labeled use? Unlabeled use? Renal?
Dual purpose non-selective beta-blocker and potassium-blocker. Decreases rate and prolongs action potentials.
Labeled: Conversion of sustained VT, maintenance after AF converted to NSR.
Unlabeled: NSR maintenance in AF with hypertrophic cardiomyopathy with preserved LV mass and function.
Renal: Must be adjusted.
Sotalol contraindications?
- Bradycardia
- 2-3rd degree heard block
- Long QT
- Heart Failure
- Cardiogenic shock
Which of the “three main” Beta Blockers can be used in a patient with Heart Failure? Which cannot?
Safe in HF: Metoprolol and Carvedilol
CI in HF: Sotalol
Which of the “three main” Beta Blockers cannot be used in a patient with Heart Block? Which can and in which type?
No use in Heart Block: Metoprolol and Carvedilol
Safe in 1st degree heart block only: Sotalol
What is the class, MOA, indication, and CIs for Ibutilide?
Class III
MOA: K+ channel blocker, prolongs refractoriness
Converts acute Afib/Aflutter to NSR. Used with electric cardioversion to lower energy for shock.
CI: K less than 3.5, QT more than 440 msec, symptoms more than 48h
What is the class, MOA, indication, and CIs for Dofetilide? Renal?
Class III
MOA: K+ blocker, prolongs refractoriness
Acute tx of AF to NSR and maintenance.
CI: QT more than 440 msec, uncorrected K+, CrCl less than 20
What is the class, MOA, 3 indication, and CIs for Amiodarone?
Class III
MOA: K+, Na+, and Ca++ blocking. Prolongs AP and refractory period. Decrease AV and sinus node function.
Indications: Maintain NSR w/AF, breakthrough VT/VF, pulseless VT/VF
CI: Sever bradycardia, 2nd or 3rd degree AV block, cardiogenic shock
Amiodarone half-life and use with anticoagulants? Amiodarine with antiarrythmics may cause what?
55 day half-life VERY LONG!
Warfarin + Amiodarone require half-doses.
Don’t double up on antiarrythmics! No Flacanid or Propadanone or else long Q-T phenomena!
What is the class, MOA, indication, and CIs for Non-DI CCBs?
Class 4 Antiarrythmics.
MOA: Depress AV node conduction, increases AV refractoriness. Decreases pacemaker activity.
CI: 2nd-3rd degree AV block, SBP less than 90, others drug-specific
What is the class, MOA, 3 indication, and CIs for Verapamil?
Class 4 Antiarrythmic
MOA: CCB slows AV nodal conduction. Smooth and vascular muscle relaxation, improved myocardial demand in CAD.
Indication: Paroxysmal SVT, rate control in AFib/flutt, HTN
Off-label: Migraine, mania, hypertrophic cardiomyopathy
CI: SBP less than 90, sick-sinus, 2nd-3rd degree block, AF w/reentry tachycardia, preexication syndrome
What is the class, MOA, indication, and CIs for Diltiazem?
Class 4 antiarrythmic
MOA: CCB slows AV nodal conduction. Smooth and vascular muscle relax, improved myocardial oxygenation in CAD
Indication: Off-label for narrow and stable SVT after Adenosine and vagal maneuvers
CI: SBP less than 90, 2nd-3rd heart block, acute MI, decompensated HF, pulmonary congestion
What are two non-VW agents?
- Adenosine
2. Digoxin
Which category is better than Digoxin at reducing ventricular rate? Is Digoxin consistent at NSR correction? Toxicity?
Beta-blockers are more effective.
Inconsistent at NSR correction.
Digoxin can become toxic.
What is the class, MOA, indication, and CIs for Adenosine?
No class.
MOA: Rapid and reversible AV block, slows AV node conduction interrupting re-entry pathways
Indication: Terminated SVT from AV nodal re-entry tachycardia
CI: WPW, 2nd or 3rd degree heart block, symptomatic bradycardia
What can Adenosine help with the diagnosis of? Half-life and excretion?
Allows diagnosis of latent pre-excitation from accessory pathways in patients with atrial arrhythmias and normal ECG during sinus rhythm
Half-life: 10 seconds
Excretion: 30 seconds
What is the class, MOA, indication, and CIs for Digoxin?
No class.
MOA: Inhibit Na+/K+ ATPase pump. AV nodal suppression, increase period, reduced conduction velocity by increased vagal tone
Indication: Rhythm control. Suppresses Afib induced VT
CI: Digoxin hypersensitivity, vfib
What rhythm change can Digoxin cause from toxicity?
Prolonged PR-interval shows up at longer R-R on strip.
Sagging ST and ST segment depression.
Which is the only antiarrythmic to DECREASE refractory period?
Lidocaine. Class Ib. Na+ blocker.
What are the three types of SVT?
- Afib/Aflutter
- Paroxysmal Supraventricular tachycardia (PSVT)
- Atrial Tachycardia
What is the last drug to use in paroxysmal or persistent atrial fibrillation only after medication risks have been considered and when other antiarrhythmic agents have failed or have been contraindicated?
Adenosine (make sure about this answer)
Which two antiarrythmics are not used in PTs with structural heart disease?
Flecainide
Propafenone
In PT with new AFib but no symptoms what is best rate-control med?
Metoprolol Succinate
Does gingival hyperplasia happen with Amiodarone?
No
Is Verapamil appropriate in a PT with wide-QRS tachycardia?
No
What is Sotalol’s CrCl contraindication?
CrCl less than 40
What is drug of choice for Torsades?
Magnesium
What is done to Procainamide in a PT with history liver impairment?
Reduce Procainamide dose by 50%