Cardiology 2 - Conduction Disorders

___ = Sinus bradycardia + symptoms (light headed, fatigue, dyspnea, syncope)

Sick Sinus Syndrome

Meds that can be used to reverse sinus Brady?

- CCBs (diltiazem)

- Beta-blockers (metoprolol)

- Digoxin

- precedex

- clonidine

- opiates (methadone)

___ AV block occurs when the PR interval is prolonged

1st degree

___ AV block occurs when the PR interval gets longer and longer then a QRS beat is dropped

2nd degree type I

___ AV block occurs when the PR interval stays the same with each beat, then a QRS is dropped

2nd degree type II

___ AV block occurs when the atria and ventricles are no longer communicating

3rd degree

Tx of AV blocks?

- dependent on symptoms and medication efficacy

- permanent pacemaker (can be dual or single chamber)

Bundle branch blocks can affect ventricular ___ and can be caused by ischemia, fibrosis, scar and infection.

synchrony

Tx of bundle branch blocks?

- often none

- can progress to higher level block (avoid meds to make it worse)

Dominant S wave in V1, broad monophasic R wave in lateral leads, AVL, V5-V6, and absence of Q waves in lateral leads indicates ___

left bundle branch block

RSR patterin in V1-V3, wide slurred S waves in lateral leads, AVL, and V5-V6 indicates ___

right bundle branch block

___ can occur in patients with COPD/pulmonary issues or it can be related to medications/stimulants

Premature atrial contraction

Tx of PAC?

- dependent on symptoms and health

- if symptomatic avoid caffeine, alcohol, meds (stimulants/decongestants), manage stress

- Rx: magnesium, BB, CCB, anti-arrhythmics

___ occurs with a regular rhythm rate of 150-200+

Supraventricular tachycardia

Tx of sustained stable SVT? (systolic >90, sats >94%)

- vagal maneuvers

- adenosine IV

- BB

- CCB

- antiarrhythmics (amiodarone)

Tx of sustained unstable SVT? (hypotensive, AMS, shock)

cardioversion (shock)

What is the most common narrow complex tachycardia?

AVNRT

What typically causes AVNRT to start?

PAC

Tx for AVNRT?

- vagal maneuvers

- adenosine

- ablate

What is a typical presentation of AVRT?

short PR interval with slurred upstroke of QRS (delta wave)

___ can be contraindicated in AVRT as it can result In degeneration of tachycardia into atrial fibrillation

adenosine

Tx of choice in acute AVRT?

IV procainamide

Tx of focal atrial tachycardia?

- BB, CCB, antiarrhythmics, cardioversion and ablation

___ can be automatic, triggered, or microreentrant but causes rapid atrial rate of 160-250bpm

Focal atrial tachycardia

Irregular rate originating from the left atrium causing a rate of 200-400bpm

Atrial fibrillation

Which criteria will raise your CHADsVASC score?

- CHF

- HTN

- Age >65, Age >75

- DM

- Prior embolic event

- Female

In atrial fibrillation, CHADsVASC score will determine whether ___

to anticoagulant or not

Tx of atrial fibrillation?

- based on patient stability

- rate control: BB, CCBs, Digoxin

- rhythm control: Na+ channel blockers (quinidine, procainamide, lidocaine, mexiletine), BB, K+ channel blockers (sotalol, amiodarone, dronedarone, dofetillide), CCBs (diltiazem and verapamil)

- if need to anticoag: IV heparin or lovenox, warfarin

- oral anticoags: apixaban, dabigatran, rivaroxaban, and edoxaban

- watchman device

Atrial flutter requires ___

anticoagulation

Atrial flutter has a 50% chance of developing into ___ at 5 years

atrial fibrillation

___ is caused by a focal area of irritability that comes from the ventricles and causes an irregular rhythm

PVC

Short coupled PVCs (<40 msec) to QRS can cause ___

R on T cardiomyopathy

Tx for atrial flutter?

- CCB or BB (rate control)

Tx of PVC?

- reassurance

- BB/CCB

- antiarrhythmics

- behavior modification

- Mg

- ablate

A ___ is caused by the heart contracting but the pulse not reaching the periphery

pulse deficit

___ occurs when the sinus node stops working and the ventricles take over to create the heartbeat

idioventricular rhythm

Which type of EKG finding presents as a wide QRS with no p waves?

idioventricular rhythm

Tx for idioventricular rhythm?

- try to identify underlying cause

- emergent atropine

- pacemaker

Which rhythm is characterized by wide/regular QRS with a rate over 120?

Ventricular tachycardia

What is the cutoff for sustained vs. non sustained v tach?

30 seconds

The slower the rate of the V Tach the ___ the heart

sicker

Tx of stable v tach? (BP stable, >100 systolic, O2 >94%)

- BB/CCB (rate control)

- anti arrhythmic (amiodarone, lidocaine)

- sedation/cardioversion

Tx of unstable v tach? (hypotensive, hypoxic)

- sedate/cardioversion

- start pressers and anti-arrhythmic (amiodarone/lidocaine/procainamide)

- cardio consult stat

Long-term tx of v tach?

Normal heart:

- CCB/BB

- antiarrhythmics (mexiletine, flecainide, sotalol, amiodarone)

- ablation

Abnormal heart:

- BB(non-selective)/CCB

- antiarrhythmics (mexiletine, amiodarone, quinidine)

- ICD and possible ablation

Tx of ventricular fibrillation?

- call a code + shock

- underlying cause

- antiarrhythmics

- ICD

What is another name for torsades de points?

polymorphic ventricular arrhythmia

Torsades de points can degenerate into ___

v fib

Tx of torsades de points?

- treat underlying cause

- magnesium

- ICD if all else fails

___ is either inherited or acquired secondary to medications

Long QT syndrome

Tx of long QT syndrome?

- non-selective BB

- potentially ICD if cardiac event

___ occurs within 1 hour of onset of symptoms or during sleep most often cardiac arrhythmia.

Sudden death

70-80% of sudden death cases are related to ___

ischemia or chronic LV dysfunction