clinical tx of arrhythmia 4

Question 1

Ventricular Tachyarrhythmias: when is defibrillator needed?

Answer 1

1. secondary prevention
2. primary prevention
3. medication and ablation are inferior to internal defibrillator, which is the ONLY tx shown to confer mortality benefit in these situations

Question 2

Secondary prevention:

Answer 2

When the patient has had a sudden cardiac arrest due to VT or VF without a reversible cause (ischemia, drugs, electrolytes).

Question 3

Primary prevention:

Answer 3

When the patient has not had a cardiac arrest but is at significant risk.
1. ischemic heart disease, low ejection fraction < 35% despite medical therapy.
2. ischemic heart disease, EF 35-40%, and inducible VT at EP study.
3. certain structural heart diseases with high risk of cardiac arrest:
hypertrophic cardiomyopathy, cardiac sarcoid, congenital heart disease, ARVC.

Question 4

Currently, the best available treatments for sudden cardiac death is

Answer 4

bystander basic life support and early defibrillation with an external defibrillator.

Question 5

other tx for SCD: acute therpy

Answer 5

1. BLS
2. defibrillator timing
3. first responder AED
4. Biphasic waveform
5. Public AED
6. pre-defibrillation CPR
7. induced hypothermia
8. antiarrhythmics
9. vasopressin in asystole
10. early ACLS
11. thrombolysis in PEA

Question 6

Tachyarrhythmia Take Home Points

Answer 6

1. Tachyarrhythmias are divided into supraventricular arrhythmias and those coming from the ventricle.
2. Any unstable tachyarrhythmia: SHOCK.
3. Treat and reverse the underlying causes.

Question 7

Only available treatments for sudden cardiac death:

Answer 7

basic life support and early defibrillation. YOU- as a potential bystander- can make a difference.

Question 8

Most sudden deaths from ventricular arrhythmias occur in

Answer 8

general population before they can be risk stratified.

Question 9

There are a variety of treatment options for SVTs and they should be

Answer 9

individualized to a patient’s characteristics, and the risks and benefits should be weighed.

Question 10

Decisions regarding implantable defibrillators

Answer 10

1. structural heart disease

2. what is risk of sudden death with the arrhythmia

Question 11

SVT: treatment is

Answer 11

individualized according to the specific mechanism so

MAKE THE DIAGNOSIS (Adenosine to see p waves).

Question 12

Chronic Management of AF

Answer 12

1. rhythm control
   a. To achieve and maintain sinus rhythm
2. rate control
   a. To achieve resting heart rate 60-80 /min
   b. To reduce undue increase of heart rate during exercise
3. prevent thromboembolism
   a. Anticoagulation or anti-platelet treatment, based on risks of stroke

Question 13

Rhythm-control strategy

Answer 13

Try rhythm-control first for patients with AF:

1. who are symptomatic
2. who are younger
3. presenting for the first time with lone AF
4. secondary to a treated/corrected precipitant
5. with congestive heart failure

Question 14

Rate Control should be used for

Answer 14

1. Patients unsuitable for cardioversion, like
   a. Comorbidities
   b. decompensated heart failure
2. All patients with rapid AF initially to relieve symptoms

Question 15

control achieved in slowing:

Answer 15

1. resting HR

2. HR during exercise

Question 16

rhythm control: cardioversion is more likely to succeed if

Answer 16

1. Recent onset AF
2. No structural heart disease
3. Successful treatment of precipitating causes: eg thyrotoxicosis, infection
4. Young age
5. Acute onset AF eg MI , Acute heart failure

Question 17

rhythm control: cardioversion is associated with

Answer 17

increased risk of thromboembolism during procedure

1. Therefore warfarin, with INR 2-3, for 3 weeks prior to DC shock
2. Or if onset of AF within 48 hours – IV heparin
3. IF AF > 48 hours, transesophageal echocardiogram to rule out thrombus before cardioversion
4. All patients maintained on anticoagulation for at least 4 weeks after cardioversion