Arrhythmias Flashcards
causes first degree AV block
(conduction delay in AV node)
autnomic, transient AV ischemia, drugs, MI, degenerative aging
define Vtach
series of >3 PVCs
sustained VT>30seconds
long term therapy consideration for sustained VT
ICD
ECG mobitz II
QRS widened due to His disease
sudden loss of AV conduction without preceding gradual PR leegnthening
Torsades de pointes observed in pts with
QT prolognation due to drugs, brady carida, electorlyte distubances, or congenital long QT (ion channel abnormality)
WPW (in Atrioventricular reentrant tachy) ECG delta wave
short PR
Slurred QRS due to slow vent activations, wide
QRS coming out to meet P wave
(in orthodromic tachy, no delta wave as anterrade depol of ventricles occurs only over AV node path)
treatment Vfib
immediate defib,
later consider IV amiodarone
escape rhyhtm qualities
typically narrow
40-60bpm
not perceded by normal P wave
(may have retrograde - inverted after QRS in inferior leads)
treatment 3rd degree AV block
pacemaker
symptoms torsafes
lightheadedness
syncope
sudden cardiac death
ECG A fib
no distinct P waves,
irregularly irregular
ECG monomorphic VT
identical QRS (typically wide)
no p waves
chronic AV nodal reentrant tachy treatment
AV nodal block
cathetar ablation
Class I and III antiarrhythmics
ECG Atrial premature beats / atrial Tachycardia
early P wave with abnomral shape
underlying mechanism polymorphic VT
multiple ectopic focci or changing reentrant circuit
CHADVASc treatment levels
0 - no therapy or aspirin
1 - aspirin or oral anticoag
>2 oral anti coag
ECG Mobitz I (2 degree AV block)
(intermittent failrue of AV conduction)
PR gradually increases until completely blocked, then normalizes
(usually benign and asymptomatic)
pathophysiogy Mobitz II
conduction block distal to AVN > sudden intermittent lsos of AV conduction
> (may progress to 3 degree without warning = need pacemaker)
treatment atrial premature beats / atrial tachycardia
beta blockers (if symptomatic)
drugs that slow atrial flutter circuit (eg ___) may promote 1:1: Av conduction, increasing ventricular rate
felcainide
Bradyarrhythmias: 1:1 relationship between P and QRS =
sinus bradycardia
first degree AV block
Bradyarrhythmias interment block between P and QRS =
second degree AV block (Mobitz I or II)
2:1 AV block
ECG First degree AV block
PR elongation
PR > 200ms
ECG Vfib
all fucked up
symptoms. Nodal Reentrant Tachycardia
palpitations,
dizziness
chest pain
dyspnea
3 mutations of congenital long QT
decrease outward K (LQT1+2)
increase inward K (LQT3)
pathophys atrial premature beats / atrial tachy
automaticity or reentry in an atrial focus outside of SA node
Afib predisposing factors
ETOH
vavlular disease
elarged atria
htn, coronary disease, pulmonary disease
sleep apnea
hyperthyroidism
cardiothoracic surgery
pathophysiology Av nodal reentrant tachycardia
fast and slow conduction pathways (typically antegrade from A to V occurs over slow path and retrorade limb is over fast path)
presentation atrial flutter
asymptomaic
palpitations, dypsnea,
weakness
stroke from atrial thrombus
associated causes Polymorhpic VT
long QT with Torsades
acute ishemia/infarct
inherited Ca handling abnormalities
SInus tachycardia results from
increased sympathetic
decreased parasympathetic tone
origin sinus tachycardia
SA node
predisposing factors atrial flutter
prior heart surgery
coranary disease
cardiomyopathy
ECG premature ventricular beats or contractions (PVCs)
widened QRS (impulse from ectopc ventriclar site)
no p wave relation (ventricular origin) OR inverted p in II III aVF (retrograde VA conduction)
sustained polymorphic Vtach leads to
syncope
arrest
sick sinus syndrome
intrinsic SA node disease causing inappropriate brady cardia with dizziness, confusion or syncope
sustained monomorphic VT rypically result sfrom
reentry and indicates underlying tissue path (scar, structural heart disease)
chronic Torsades treatment
correct underlying triggers
if congenital long QT - beta blocker
ECG Third degree AV block
no relationship between P and QRS compelxes
proximal escape = narrow QRS
distal escape = wide QRS
complete failure of atrial>ventricle conduction
Bradyarrhythmias: dissociated P and QRS =
complete heart block
underlying mechanism afib
triggered by rapid firing from atrial foci often localized to atrial muscle extending into pulmonary veins
PVCs tx
observation
beta block
ECG AV nodal reentrant tachy
**antergrade fast path: **P waves superimpose on QRS, regualr RR (no pwave)
**anterograde slow path: **narrow complex tachy, regular RR, inverted P waves in inferior leads aVF II III
ECG Polymorphic VT
QRS continually changes shape and rate (typically wide)
Atrioventricular reeentrant tachycardias =
reentry utilizing bypass tract or acessory pathway - band of muscle cells connecting atria and ventricle
produces WPW
acute treatment AV nodal Reentrant Tachycardia
valsalva
adensoine
beta block
ca block
treatment atrial flutter
Rate control: beta blockers, Ca blockers, digoxin
Rhythm control - >48hrs = TEE to rule out left atrial thrombus OR 3 weeks coagulation > cardioversion
anticoagulation 4 weeks past cardioverion
pace termination (rapid atrial pacemaker)
Ablation of tricuspid caval isthmus
aniarrhythmics (class I, III)
treatment AFib
Anticoag (acute:cardoversion) (chronic - CADSV score)
Rate control: AV blockage (beta block, Ca block, digoxin)
Resotoration of sinus rhythm: cardioversion, antiarrhythmatics,
cathetar ablation
ECG atrial flutter
sawtooth pattern
AV conducion variable, commonly more flutter waves than QRS complexes
acute treatment torsades
cardiovert sustained VT to restore sinus rhythm
IV magnesium
correct underlying abnormality (drugs)
elevate HR to shorten QT (beta agonists or pacing)
treatment WPW
IV amiodarone or procainamide (I or II) to slow accessory pathway conduction
(NO digoxin, beta or Ca block - shorten refractory period of accessory = faster)
cardioversion if iunstable
high risk = cathetar ablation
clinical consequences of afib
rapid ventricular response rate > hypotension or heart failure
blood stasis > clots > thrombus
ECG Sinus Tachycardia
normal P and QRS
CAD2-VASc criteria
- *C**- congestive HF 1 pt
- *H **Hypertension -1 pt
**A- **age > 65 1 pt
**D- **diabetes 1 point
V- vasc disease
**A2 **- age > 75 - 2 points
Sc - Sex female
if atrial premature beats genreates consecutive beats resuling in HR >100 it is termed____
atria tachycardia
Afib is sustained by multiple wanering reentrant circuits, minimum number of circuits is required thus Afib promoted by
elarged atrium
symptoms 3rd degree AV block
lightheadedness
syncope
exercise intolerance
counterclockwise atrial flutter
right atrial depol down septum >
>roof>
>down RA free fall >
>floor of RA between tricuspid and inf vena cava (isthmus)
