HF & Arrythmia exam Flashcards
What are the class 1a antiarrhythmics?
mixed block of Na & K channels —> prolongs QT
-Quinidine, procainamide
What are the class 1b antiarrhythmics?
weak Na channel block —> no significant effect on ECG
-Lidocaine, mexiletine, phenytoin
What are the class 1c antiarrhythmics?
strong Na channel block —> widens QRS complex
-Flecainide
What are the class 3 antiarrythymics?
K+ channel blockers; agents that prolong refractory period and QT interval
-Amiodarone, dronedarone, sotalol, Ibutilide, Dofetilide
What are the class 2 antiarrythmics?
Beta adrenergic blockers
-Esmolol (cardioselective), acebutolol (cardioselective), propanolol (nonselective)
-slows pacemaker cells and Ca2 currents; increase PR interval
What are the class 4 antiarrythmics?
Ca+2 channel blockers
-Verapamil, Diltiazem
-frequency dependent block of Cav1.2 channels; blockade accumulates in rapidly depolarizing tissue (tachycardia)
What phase does the class 1 (Na channel blockers) work in?
-phase 0
What phase does the class 2 (Beta-blockers) work in?
-phase 4
What phase does the class 3 (K channel blocker) work in?
-phase 3
What phase does the class 4 (Ca channel blocker) work in?
-phase 2
What drugs increase PR interval?
beta-blockers (Esmolol, acebutolol, propranolol)
Ca Channel blockers (verapamil, diltiazem)
What drugs widens QRS complex?
Class 1c drugs (Flecainide, propafenone)
What drugs lengthen QT?
Class 1a drugs (Quinidine, procainamide, disopyramide)
Class 3 drugs (amiodarone, dronedarone, sotalol, Ibutlilide)
What drugs have no ECG changes?
Class 1b drugs (Lidocaine, Mexiletine)
What type of fibrillation has no P waves?
atrial fibrillation
-irregularly irregular rhythm
-abnormal pulmonary vein automaticity & mult. re-entry circuits
What is the chads-vasc score?
Congestive heart failure, Hypertension, Age > 75 years (2 pts), Diabetes, Stroke/TIA/TE history (2 pts), Vascular disease, Age 65-74 years, Sex (female)
When is Warfarin indicated over DOACs for afib?
-if pt has mechanical heart valves (target INR 2.5-3.5)
-if pt has heart valve disease (moderate/severe mitral valve stenosis) (target INR 2-3)
What anticoagulation medication for afib is indicated in ESRD?
apixaban
What drugs are indicated for acute ventricular rate control in afib if patient is hemodynamically stable + decompensated HF?
-amiodarone
What drugs are indicated for acute ventricular rate control in afib if patient is hemodynamically unstable?
DCC (direct current cardioversion)
What drugs are indicated for acute ventricular rate control in afib if patient is hemodynamically stable + no decompensated HF?
B-blockers, diltiazem, Verapamil
2nd line: digoxin
3rd line: amiodarone
What drugs are indicated for long-term ventricular rate control in afib + HFrEF?
B-Blockers, 2nd line: digoxin
What drugs are indicated for long-term ventricular rate control in afib (no HFrEF) ?
B-Blockers, Diltiazem, verapamil 2nd line: digoxin
-interaction between digoxin and verapamil
What drugs are indicated for converting AF to SR (hemodynamically stable) ?
IV amiodarone, Ibutilide, procainamide (faster acting, higher risk of torsades des pointes)
-procainamide cannot be be administered with amiodarone or Ibutilide
What drugs are indicated for converting AF to SR if pt has HFrEF?
IV amiodarone
What is the dosing for dofetilide?
-monitor in hospital
-d/c if QTc > 500 ms or increases by > 15%
500 mcg BID = CrCl > 60 mL/min
250 mcg BID = CrCl 40-60 mL/min
125 mcg BID = CrCl 20-39 mL/min
What are the adverse effects and monitoring parameters of amiodarone?
AE’s: blue-grey discoloration, photosensitivity, corneal microdeposits, pulmonary fibrosis, hepatoxicity, bradycardia, hypo/hyperthyroidism
Monitoring: TSH, LFTs, ECG, chest X-ray for pulmonary fibrosis (once when starting then if symptoms)
What drugs are indicated for maintenance of SR following conversion for afib with normal LV function, no prior MI or significant structural heart disease?
Dofetilide, dronedarone, Flecainide, Propafenone
2nd line: Amiodarone 3rd line: Sotalol
What drugs are indicated for maintenance of SR following conversion for afib with prior MI or significant structural heart disease, inlcuding HFrEF?
amiodarone, dofetilide, dronedarone
2nd line: Sotalol
-if pt is NYHA class III or IV then dronedarone is CI
How do you administer Adenosine?
dose is 6 mg IV, then 12 mg IV then a second dose of 12 mg IV again
How do you treat symptomatic PVCs and have no CAD or HF?
B-Blockers, diltiazem, verapamil
2nd line: antiarrythmic medication; catheter ablation
How do you treat symptomatic PVCs w/HF?
B-Blockers
How do you treat symptomatic PVCs w/CAD?
B-Blockers, diltiazem, or verapamil
2nd line: antiarrythmic medication
What is the algorithm for termination of stable VT and structural heart disease?
DCC
2nd line: IV procainamide
3rd line: IV amiodarone or IV Sotalol
What is the algorithm for termination of stable VT if no structural heart disease?
if Verapamil-sensitive VT then treat with Verapamil
If outflow tract VT then B-Blocker
if fails, then DCC
What is indicated for ventricular fibrillation treatment?
Defibrillation
-use Epinephrine 1 mg IV then 2 does of Amiodarone 300 mg IV/Lidocaine 1-1.5 mg/kg IV (1/2 dose second time)
