Clinical Treatment of Arrhythmias

Question 1

Sinus bradycardia is defined as a heart rate less than ____________.

Answer 1

55 bpm

Question 2

Sinus node arrest results in ____________.

Answer 2

temporary cessation of any depolarization

Question 3

Chronotropic incompetence is ___________.

Answer 3

the inability of the heart to increase its rate in response to increased stress

Question 4

A Mobitz 1 block results in _____________.

Answer 4

progressively prolonged PR interval until a ventricular beat is lost

Question 5

A Mobitz 2 block block results in ___________.

Answer 5

periodically missed QRS wave with constant PR intervals

Question 6

In what two scenarios would you treat bradycardia?

Answer 6

(1) when patients are symptomatic–regardless of the location of the block; and (2) when the rhythm is infranodal

Question 7

How should bradyarrhythmias be treated?

Answer 7

(1) by addressing the underlying cause–such as Lyme disease, hypothyroidism, ischemia, or neurologic issues; (2) by withdrawing the offending medication; (3) addressing acute problems with ß-agonists or transcutaneous pacing; and (4) implanting pacemakers

Question 8

What is MAT?

Answer 8

Multifocal atrial tachycardia; a form of atrial tachycardia characterized by multiple ectopic sites of pulse initiation; this is diagnosed by multiple morphologies of P waves on an ECG

Question 9

Cardiologists treat irregular supraventricular tachycardia with _____________.

Answer 9

shock (only when the patient is symptomatic and unstable), rate control, anti-arrhythmics, or cardioversion

Question 10

Cardiologists treat regular supraventricular tachycardias with __________.

Answer 10

adenosine, class I antiarrhythmics, calcium-channel blocks, or vagal maneuvers (to slow the conduction); and ablation of the errant pathways

Question 11

How does adenosine work?

Answer 11

It slows conduction to the AV node.

Question 12

AVNRT is __________.

Answer 12

Atrioventricular node re-entrant tachycardia

Question 13

AVNRT results from ______________.

Answer 13

re-entry of depolarization through the slow pathway that some people have

Question 14

AVRNT will display a ___________ ECG pattern.

Answer 14

additional P wave buried in the right side of the QRS wave

Question 15

What are accessory pathways?

Answer 15

Pathways that connect the atria to the ventricles, allowing propagation from the atria to pre-excite part of the ventricles.

Question 16

What is AVRT?

Answer 16

Atrioventricular re-entrant tachycardia; a form of arrhythmia that results from accessory pathways.

Question 17

What is the ECG pattern of AVRT?

Answer 17

A delta wave–a slightly wider QRS wave, but only in the beginning

Question 18

What causes AT?

Answer 18

Atrial tachycardia results from extra hotspots of automaticity within the atria.

Question 19

What are the three types of bradyarrhythmias?

Answer 19

AV block, bundle blocks, and SA node malfunction

Question 20

What is the only longterm treatment for bradycardiac arrhythmias?

Answer 20

Pacemakers

Question 21

Other than junctional rhythm, what can cause an ECG without P waves?

Answer 21

1:1 atrial flutter or AV-nodal re-entrant tachycardia

Question 22

Hyperthyroidism can cause ______________.

Answer 22

atrial fibrillation

Question 23

Class IC agents are contraindicated in ______________.

Answer 23

those with coronary artery disease

Question 24

Those who have ventricular tachycardia who are unstable should be ___________ while those who are stable should receive ___________.

Answer 24

shocked; amiodarone, lidocaine, or procainamide

Question 25

If ventricular tachycardia does not arise from structural heart disease (like CHF), then the cause is either _______ or ________.

Answer 25

idiopathic; due to a focal arrhythmogenic trigger

Question 26

Defribllators are only given to those with ventricular tachycardia if _______________.

Answer 26

they have had prior cardiac arrest or have concurrent heart disease

Question 27

What is Wolf-Parkinson-White syndrome?

Answer 27

AVRT–a form of regular supraventricular tachycardia that leads to a delta wave; delta waves are slower upstroke of QRS