Arrhythmias - madison Flashcards
What can cause sinus bradycardia
Drugs - beta blockers, calcium channel blockers
Conditioning - high level athletes
age
what is the presentation of sinus bradycardia
asymptomatic
fatigue, DOE - chroniotropic incompetence
what is the management of sinus bradycardia
nothing
remove offending agents
pacemaker? rarely
what is seen with junctional rhythm
P waves hidden within or after QRS
narrow QRS
typically slow rhythm due to AV node rate.
What is a junctional escape
AV junction has a faster firing rate than the SA node
what is asystole
complete absence of demonstrable electrical and mechanical cardiac activity
What is the mechanism of sinus node dysfunction
fibrosis of the sinus node (age)
cardiorespiratory conditioning
medication suppression (beta-blockers, CCB)
chronotropic incompetence (cannot meet the demand of exertion)
What is the presentation of sinus node dysfunction
asymptomatic at rest
Exertional fatigue/DOE
unconscious
What is the management of Sinus Node dysfunction
reversible causes
atropine (short term)
transcutaneous pacing vs TVP via RIJ
pacemaker
what is the mechanism of sinus arrrhythmias
normal physiologic cardiac cycles
inspiration HR: increases
Expiration HR: decreases
what is the management of sinus arrhythmias
none
What is the mechanism of sinus tachycardia
stimulation of the sinus node
adrenergic response (fight/flight, anxiety)
infection
PE
what is the presenation of sinus tachycardia
asymptomatic
variable depending on underlying cause
what is the management for sinus tachycardia
First line: treat reversible causes
then consider beta-blockers
What are the mechanisms of Afib
wavelets of re-entrant activation (pulmonary veins)
what are the mechanisms of aflutter
circuit of re-entrant activation (cavotricuspid isthmus)
what is the presentation of afib/aflutter
asymptomatic
palpitations
fatigue
DOE
stroke/CVA
what is the management for stable afib
anticoagulate (CHA2DS2-VASc)
rate control
rhythm control
what does MAT stand for
Multifocal atrial tachycardia
> 100bpm and 2 different shapes of P waves
what does WAP stand for
Wandering Atrial Pacemaker
<100bpm and 2 different shapes of P waves
What is the mechanism for MAT/WAP
mutliple atrial ectopic foci
what is the presentation of MAT/WAP
can be similar to afib
most pts are hemodynamically stable
how do you manage MAT/WAP
oxygen levels and treat underlying causes
What is the mechanism of SVT
circuit allowing rapid conduction from A to V
AVNRT * most common
AVRT
what is AVNRT
Atrioventricular nodal re-entrant tachycardia
most common SVT
what is AVRT
atrioventricular re-entrant tachycardia
- not reliant on the node
What is the presentation of SVT
palpitations
lightheadedness
“heart racing”
presyncope/syncope
History: bending down motions (AVNRT until proven otherwise)
What is the acute management of SVT
vagal maneuvers
adenosine (diagnostic and therapeutic)
Cardioversion (DCCV)
what is the chronic management of SVT
rate control
antiarrhythmics (flecainide)
Ablation
What is the mechanism of heart block
disease of the AV node
-fibrosis
-beta-blockers/CCB toxicity
-infection
-ischemia/infarct
-iatrogenic
-infiltrative disease
-congenital
what is the presentation of Heart block
SOB
lightheadedness
syncope
what is the management for heart block
acute (if HD unstable): transcutaneous packing vs TVP via RIJ; atropine, dobutamine
chronic: pacemaker
how do you treat torsades de points
*magnesium
shock
overdrive pace
What are the mechanisms for Vtac
ischemia/infarct
Drugs
toxicity
metabolic derangements
Prolonged QTc
what is the presentation for Vtac
unconscious, pulseless
SOB, lightheadedness, palpitations
what is the management for Vtach
ACLS
amiodarone
lidocaine
Cardioversion
Defibrillation
TdP: Mag, more mag, overdrive pacing
What is a RBBB
complete block of impulses along the right bundle of his
“bunny ears” in V1 or V2
what is LBBB
complete block of impulses along the left bundle of His
deep R wave in V1
what do bundle branch blocks cause
wide QRS and characteristic pattern of QRS complex
What is the mechanism of Bundle Branch Blocks
fibrosis
ischemia/infarct
drugs/toxicity
what is the presentation of BBB
usually, asymptomatic
can occur int he setting of HF
what is the management of BBB
usually no intervention is warranted
new LBBB + ? ACS -> Sgarbossa’s criteria
if reduced LVEF despite GDMT and no recent revascularization - CRT
what is the mechanism of premature complexes
excitable tissue
catecholamines
what is the presentation of premature complexes
asymptomatic
palpitations
what is the management of ectopy
magnesium, decrease ETOH level, stimulant use, hormonal
