Clinical Treatment of Arrhythmias Flashcards Preview

CVPR: CV Unit I > Clinical Treatment of Arrhythmias > Flashcards

Flashcards in Clinical Treatment of Arrhythmias Deck (31):
1

Sinus bradycardia

-slow HR
-<60 bmp
-does not necessarily indicate pathology

2

Sinus arrest

-lack of sinus node discharge
-absence of p wave and absence

3

Bady-tachy

intermittent episodes of slow and fast rates form SA node or atria

4

Chronotropic incompetence

-HR should normally respond smoothly to excercise/stress
-unable to reach max HR smoothly and unable to maintain

5

First-degree AV block

-no actual block
-AV conduction is delayed
-long PR interval (>.2 secs)
-primarily block occurring w/in AV node

6

Second-degree AV block - Mobitz I

-not every p wave transmits to ventricular contraction
-progressive prolongation of PR interival until ventricular beat is drop

7

Locations w/in conduction system where problems can d\occur

-@ sinus node
-@ AV node
-infranodal (below AV node)

8

Second-degree AV block - Mobitz II

-no progressive prolongation -- suddenly dropped QRS wave
-regular PR interval
-block primarily occurs below AV node: w/in His, bundles, or purkinje

9

Third-degree AV block

-no impulse conduction from the atria to the ventricles
-p wave

10

Indications for treating bradyarrhythmias

-patient is symptomatic and arrythymia at from any point in conduction system is detected
-when the rhythm is infranodal (below the AV node)

11

Steps in treatment of bradyarrhythmias

1. Find and treat reversible causes: i.e. ischemia/infarct, hypothyroidism, neurologic causes, lyme disease
2. Stop offending meds
3. Acute tx: beta-agonists (dopamine or isoproterenol), transcutaneous pacing, venous pacing
4. Long term: permanent pacemaker

12

Tachyarrhythmias

-Above ventricle=supraventricular tachycardias (SVTs)
-@ ventricle=ventricular tachycardia, ventricular fibrillation

13

Supraventricular tachycardia types

-regular (consistent QRS intervals w/P waves) vs. irregular
-regular: sinus tachycardia
-irregular: atrial fibrillation (no discrete Ps); multifocal atrial tachycardia (3+ Ps); atrial flutter (flutter waves)

14

Irregular supraventricular tachycardia tx

if unstable --> shock

15

Regular supraventricular tachycardia tx

-give adenosine
-adenosine may slow down rhythm to help dx arrythmia
-adenosine may also slow down AV node and actually treat/terminate tachycardia

16

Atrial fibrillation approach

-5 C's:
-Cause: reverse
-Control rate
-antiCoagulation --> @ risk for stroke, must prevent clots
-Control rhythm
-Cure?: ablation

17

Common causes of AF

-hypertension
-mitral valve disease
-alcohol
-cardiomyopathy
-hyperthyroidism
-lone AF
-cardiac surgery

18

Immediate Treatment of Atrial fibrillation

-cardiovert (shock) if close to hemodynamic collapse
-control rate if

19

Rhythm control in Atrial fibrillation

-pharmalogical: less successful, but does not require sedation --> Class IC (flecainide, prpafenone) and Class II anti-arrhythmics (ibutilide, amiodarone, dofetilide, sotalol)
-electrical

20

Maintenance rhythm control in AF

-can use meds at lower doses
-Class IC agents: contraindicated inCAd and structural heart disease
-Class III agents: amiodarone, sotalol, dofetilide, dronedarone

21

Rate control in AF

-medications: beta blockers, digoxin, verapamil, diltiazem, amiodarone as rate-control in decompensated HF
-Digoxin=not good during exercise
-Beta-blockers and Ca channel blockers control HR during exercise

22

Rhythm control: catheter ablation

-surgical technique that cauterizes atrium to prevent triggers from pulmonary veins from getting into atrium

23

Atrial flutter treatment approaches

-similar to Afib
-can be more difficult to control rate or rhythm
-catheter ablation more successful than meds (95% cure rate)

24

Other SVTs (3)

-AV nodal reentrant tachycardia
-accessory pathway-mediated tachycardias: abnormal connection between atrium and ventricle
-focal atrial tachycardias: least common, abnormal focus w/increased automaticity

25

Treatment approaches to other SVTs

-individualized tx
-catheter ablation

26

Ventricular Tachyarrhythmias characteristics

-"more Vs than As" = more QRS waves than P waves
-wide complex tachycardia usually indicates ventricular origin
-CAD = 90% of time it is VT

27

Acute tx in stable Vtach

-meds: amiodarone, lidocaine, procainamide
-treat underlying causes

28

Acute tx in unstable Vtach

-shock
-treat underlying causes
-meds

29

Approach to Vtach w/out structural heart disease

-usually idiopathic: focal arrythmogenic trigger
-usually "benign"
-meds or ablation
-defribillator rarely necessary

30

Approach to Vtach w/ structural heart disease

-treat underlying causes
-risk stratify
-defribillator + meds/ablation

31

Reasons for defribrillator in Vtach

-secondary prevention: pt who has already had sudden cardiac arrest due to VT/VF w/out a reversible cause
-primary prevention:pt w/out previous cardiac arrest but is at significant risk