Cardiac Arrhythmias

Question 1

sinus bradycardia tx

Answer 1

acute + sx –> atropine, temporary pacemaker

chronic –> permanent pacemaker

Question 2

tx of first degree AV block

Answer 2

none, usu asymptomatic

Question 3

tx of Mobitz II

Answer 3

permanent pacemaker

His-purkinje block, hanging by a thread. usu w/ BBB, could progress to asystole, wide QRS

Question 4

tx of Moitz I

Answer 4

asymp
usu no tx needed

(Wenckebach)

Question 5

3rd degree heart block tx

Answer 5

atria and ventricle beating independently of one another

permanent pacemaker

Question 6

a fib

Answer 6

absent p wave
atrial activity represented by fibrillatory waves

tx:
1. stroke prevention
2. slow ventricular response
3. restore and maintain NSR (synchronized shock to chest wall to depolarize all myocardial cells, pulmonary v. ablation)

Question 7

ablation in afib tx

Answer 7

ablation of myocytes surrounding pulm v.

Question 8

a flutter tx

Answer 8

sim to afib

rate control and anticoagulation

electrical cardio version = successful

catheter ablation of RA (destroying small strip of atrial m. in isthmus of tissue between tricuspid annulus and IVC)

Question 9

SVT (supra ventricular tachycardia) differential dx

Answer 9

AVNRT
AVRT
atrial tachy

Question 10

SVT (supra ventricular tachycardia) tx

Answer 10

acute: cardioversion if hemodynamically unstable
chronic: ablation or antiarrhythmics such as beta blockers, CCBs or other antiarrhythmics

Question 11

SVT acute tx (stable)

Answer 11

1. vagal maneuvers (valsalva, carotid massage)
2. adenosine (arrhythmia terminator)
3. verapamil
4. synchronized cardioversion

Question 12

AVNRT tx

Answer 12

-catheter ablation to destroy cells in slow path

Question 13

ECG dx of WPW

Answer 13

1. narrow PR
2. normal P wave vector (exclude junctional rhythm)
3. delta wave
4. QRS >100

Question 14

tachycardia - afib WPW syndrome

Answer 14

feared complication –> rapid atrial tachyarrhythmia is conducted solely down the accessory bypass tract and not subj to decrememnral conduction prop of AV node –> can lead to Vfib/cardiac arrest

AVOID digitalis (digoxin), CCB (slow AV conduction)

tx: IV procainamide or IV amiodarone. If unstable –> immediate cardioversion

Question 15

What is often indicated in pt w/ WPW at risk for sudden death due to atrial fib w/ rapid ventricular response via the bypass tract?

Answer 15

AVRT

Question 16

focal atrial tachycardia

Answer 16

• focal tachycardia originating in atrial muscle other than sinus or node
• may have single or multiple foci capable of depolarization at rapid rates
• SA firing and other atrium area firing somewhere else competing w/ SA node

tx: slow rate (BB, CCBs), ablate

ECG: P waves are clearly discernible, PR interval is normal

Question 17

V tachy

Answer 17

-wide complex rhythm w/ rate >100bpm originating from the ventricle

acute tx: stable –> lidocaine, unstable –> cardioversion

chronic tx: drugs, ablation, implantable cardioverter defibrillator

Question 18

drugs for STABLE sustained monomorphic VT

Answer 18

• lidocaine

- amiodarone

Question 19

drugs for UNSTABLE sustained monomorphic VT

Answer 19

synchronized cardioversion

Question 20

ventricular fibrillation

Answer 20

• wide QRS, not organized
• pt is sweaty, SICK

acute tx: defibrillation (AED)

chronic tx: ICD. Lead implanted at RV apex via subclavian v. or subQ. ICD over pectoralis m. or at cardiac apex