EP III and IV

Question 1

Findings favoring the diagnosis of ventricular tachycardia

Answer 1

History of coronary artery disease and decreased EF,
Atrioventricular dissociation,
Capture or fusion beats.

If the patient has coronary artery disease and a depressed ejection fraction (EF), the wide complex tachycardia is almost certainly ventricular tachycardia.

Question 2

what are the types of ventricular beats?

Answer 2

Single Premature Ventricular Contractions (PVC’s)
Couplets, bigeminy and trigeminy
accelerated idioventricular rhythm (>3 ventricular beats at rate under 120 bpm)
ventricular tachycardia (>3 ventricular beats at rate over 120 bpm)

Question 3

how do you treat an asymptomatic patient with wide complex beats?

Answer 3

none unless K or Mg levels abnormal which you should treat

Question 4

how do you treat a symptomatic patient with a normal heart that has wide complex beats?

Answer 4

no need unless interfering with daily activities, in which case you should give a beta blocker (1st line) or antiarrhythmic

Question 5

what are some problems that arise in treating patients with abnormal hearts that have wide complex beats?

Answer 5

treatment may be pro-arrhythmic

a Na+ or K+ channel abnormality may make treatment more dangerous

Question 6

what is accelerated idioventricular rhythm?

Answer 6

it is a wide QRS complex beat that is slower than ventricular tachycardia
often seen in recovery of acute MI
not the same prognosis as VTach

Question 7

What is ventricular tachycardia?

Answer 7

wide QRS complex rhythm

to differentiate from functional BBB look for AV dissociation (or fusion beats)

Question 8

what is the ventricular fibrillation prognosis?

Answer 8

often very poor unless terminated with defibrillation (but not always)
common during cardiac arrest
The type of ventricular arrhythmia, existence of CAD, degree of LV dysfunction increase the risks

Question 9

What was the Cardiac Arrhythmia Suppression Trial (CAST)?

Answer 9

To determine if suppression of ventricular ectopy would decrease mortality.
Patients with 6 or more PVC’s per hour, a prior MI and an abnormal EF were eligible for enrollment.
Flecainide, encainide and morizicine were compared to placebo in this population.
The CAST trial was terminated early when analysis demonstrated a worse mortality with treatment than with the placebo.

Question 10

Should you use Class IC in patients with arrhythmias?

Answer 10

no –> increased mortality

Question 11

should you use class IA drugs in patients with ventricular arrhythmias?

Answer 11

no

Question 12

should you use use class III drugs in patients with ventricular arrhythmia?

Answer 12

yes: amiodarone,dl-sotalol and dofetilide

neutral effect on mortality

Question 13

what is the most effective treatment for the secondary prevention of SCD?

Answer 13

ICD

Question 14

How does ICD effect survival in vtach?

Answer 14

most beneficial for those with EF <35 and those with ischemia
patients with non-ischemica cardiomyopathy would benefit just as equally from amiodarone

Question 15

what treatment leads to the best survival in patients with significant LV dysfunction?

Answer 15

ICD

Question 16

what do you do for patients with ventricular arrhythmia but no evidence of CAD

Answer 16

drug induced long QT? most likely a QT prolonging antiarrhythmic (dofetilide)
metabolic induced?
or congenital long QT syndrom

Question 17

How do you diagnose congenital long QT syndrome? What is the mortality?

Answer 17

prolonged corrected QT interval (Qtc) in a patient experiencing syncope with a family history of unexplained death in relatives under the age of 30. Abnormality is genetic defect in the DNA coding voltage dependent potassium channels (KVLQT1) and cardiac sodium channels (SCN5A). The mortality in the year following the onset of syncope is 20% and 50% in the following 5 years

Question 18

what are the forms of congenital long QT syndrome

Answer 18

Romano-Ward : autosomal dominant inheritance

Jervell-Lange-Nielsen : autosomal recessive, associated with congenital deafness

Question 19

what is brugada syndrome?

Answer 19

inherited ion channel abnormality that leads to an increased risk of sudden death is characterized by an abnormal ST segment in ECG lead V1 and V2

Question 20

What are the markers of increased SCD risk in patients with hypertrophic cardiomyopathy?

Answer 20

Syncope or presyncope
Nonsustained ventricular tachycardia
Palpitations
Family history of sudden cardiac death.

Question 21

How does scarring effect onset of arrhythmias?

Answer 21

Atrial scars lead to increased incidence of atrial arrhythmias, especially atrial fibrillation
  Ventricular scars (related to VSD repair and 	correction of pulmonary stenosis) predispose to ventricular arrhythmias

Question 22

what drugs dor supraventricular arrhythmias respond to?

Answer 22

Vaughn-Williams Class Ia, Ic and III drugs
Vaughn-Williams Class II and IV may be useful if the AV node is involved
Vaughn-Williams Ib drugs do not appear to be useful in the treatment of supraventricular rhythms.

Question 23

what drug has been shown to reduce the risk of stroke in patients with atrial fibrillation and flutter?

Answer 23

warfarin and to a lesser degree aspirin

Question 24

How do you treat a symptomatic and unstable patient with atrial fibrillation

Answer 24

restore sinus rhythm

Question 25

how do you treat a minimally or asymptomatic patient with atrial fibrillation?

Answer 25

rate control or rhythm control

Question 26

how do you treat recurrent paroxysmal atrial fibrillation?

Answer 26

anticoagulation and rate control

Question 27

how do you treat recurrent persistent atrial fibrillation?

Answer 27

anticoagulation and rate control

Question 28

how do you treate a patient with atrial fibrillation and disabling symtoms?

Answer 28

antiarrhythmic drug

Question 29

how do you treat a patient with permanent atrial fibrillation?

Answer 29

anticoagulation and rate control

Question 30

what is cardioversion and what do you use it for?

Answer 30

use electricity of drugs to restore of sinus rhythm

Question 31

how long after return to sinus rhythm should a patient remain on anticoagulants?

Answer 31

3 weeks

Question 32

what is ablation therapy?

Answer 32

RF energy applied to critical portion of tachycardia circuit

For AV node reentrant tachycardia and SVT associated with WPW, the cure rate is > 95% with ablation.

Question 33

What are Class I indications for Brady Therapy (pacemaker therapy)

Answer 33

Symptomatic Bradycardia,,
Asystole > 3.0 seconds
Symptomatic complete or high grade AV block,
Asymptomatic complete heart block with an escape rate < 40 bpm.

Question 34

What are Class I indications for Tachy Therapy - defibrillator (ICD) therapy

Answer 34

Sudden cardiac death not due to a transient or reversible cause,
Sustained, spontaneous VT,
Severe LV dysfunction that persists despite appropriate therapy.