Arrhythmias Flashcards
(34 cards)
What are the sinus node rhythm disturbances?
Sinus Arrhythmia
Sinus Pause/Arrest
Sinus Bradycardia
Sinus Tachycardia
What is sinus arrhythmia? Tx
normal P, PR, QRS. rhythm sometimes appears irregular but originating from the sinus node.
-cyclic variation with respirations.
Tx: benign, not tx needed.
What is sinus pause/arrest? Tx
a missed beat, typically lasts 2 seconds to 2minutes.
-normal and fixed PR and RR intervals, lack p waves
Tx: -underlying cause
- pacemaker
- atropine IV if hemodynamic instability
Sinus Bradycarida what is this? Tx
heart rate less than 60BPM, may be caused by beta blockers and digoxin
Tx: SHORT TERM: -sx & hemodynamically unstable: atropine &/or temporary pacemaker -asymptomatic: monitor and educate
LONG TERM:
- no tx for long term if pt is asymptomatic
- will need permanent pacemaker if sx
Sinus Tachycardia
- what is this?
- causes
- tx
What: heart rate greater than 100BPM
Causes:
fever, pain, exercise, anemia, hypotension, thyrotoxicosis, anxiety
Tx:
- treat underlying cause
- calcium channel blockers (cardizem and verapamil)
- beta blockers
What are the supraventricular arrhythmias
- Supraventricular tachycardia
- -WPW
- -AV node re-entrant tachy (shortcut)
- -atrial tachy
- afib
- aflutter
PSVT
- heart rate
- ekg findings
- sx
- tx
- medications to prevent recurrence
HR 140-240
- P wave buried in QRS
- QRS is narrow** and normal morphology
Sx:
- palpitations
- dizziness
- SOB
- anxiety
- chest pain
Tx:
- Vagal maneuvers (hold breath, face in cold water, cough, carotid massage)
- adenosine IV (blocks conduction at the AV Node)
- cardioversion if adenosine doesnt work OR IV beta/Ca2+ blocker
Prevention: beta blockers ca2+ blocker digoxin SVT ablation
WPW
- HR
- what causes this
- what is it
- sx
- EKG findings
- tx
HR: greater than 200
What causes this: congenital defect, most common causes of fast arrhythmias in infants and children.
-what is this? form of SVT that uses the normal plus accessory pathways to conduct impulses faster and in both directions .
-Sx:
palpitations, tachycardia, dizzines, dyspnea, anxiety, syncope, cardiac arrest.
EKG findings:
-PR interval is short, less than 0.12ms, Delta wave*
Tx:
- radiofrequency ablation
- beta blockers
- calcium blockers
- flecainide
- vagal maneuvers
- IV adenosine OR IV cardizem or verapamil if adenosine doesnt work.
- if hemodynamically unstable cardioversion
Paroxysmal Atrial Tachycardia (PAT)
- rate
- what is this?
- ekg findings
- Tx
Rate: 150-250BPM
EKG findings:
-may conduct to ventricles but the AV node will try to block impulses
-P wave morphology varies from sinus*
Tx:
- Treated with Vagal Maneuvers
- if Vagal maneuvers fail…
- -adenosine**
- -cardioversion
- -digoxin
- -beta blockers
- -Calcium channel blockers to prevent recurrence
Premature Atrial Contractions (PACs)
- what causes this?
- EKG findings
- Tx
Cause: discharge from a non-sinus atrial pacemaker
EKG;
-p-wave preceding may not look like the p waves that originate from sinus node, may get lost in T wave.
Tx:
-non-life threatening, only treat if symptomatic w/ beta blockers.
Wandering Atrial Pacemaker
- Rate
- EKG findings
- Tx
Rate: 45-100BPM
EKG findings
-P wave; needs to have 3 distinctly different P waves
Tx: no tx required
Multifocal Atrial Tachycardia
- rate
- ekg findings
- Tx
Rate: greater than 100
EKG:
-3 different P waves in a given lead
Tx: treat the underlying medical condition
- suppress rate with AV nodal blocking agents:
- -Calcium channel and beta blockers
A-fib
- cause
- describe this rhythm
- Rate
- EKG
- common with what underlying cardiac and pulmonary dz?
cause: multiple re-entrant loops generate chaotic atrial depolarization, AV node bombarded with rates greater than 400BPM from atrial foci..AV works hard to block impulses.
Rhythm: “irregularly irrregular”
Rate: 110-170BPM
EKG:
-no distinguishable P waves
Common w/ vavlular dz, heart failure, HTN, and sleep apnea.
What is the most common encountered arrhythmia in clinical practice?
Afib
Which lab always needs to be checked with new onset of Afib dx?
TSH!
Afib Tx
Stasis of blood in atria Tx: warfarin/pradaxa
Rate Control: 60-110
-Diltiazem/Beta blocker/ Digoxin
Rhythm Control if necessary:
Class 1A: Pronestyl(Procainimide), Quinidine(Cardioquin)
Class III. Satalol(Betapace), Ibutilide(Covert), amiodarone*
Class IC: propafenone(Rhythmol), Flecainide(Tambocor) *used only in pt with structurally normal heart.
Cardioversion:
- safe to cardiovert if less than 48-72hrs of afib
- make sure to get TEE prior to cardioversion to see if thrombus present in atria.
….if duration unknown:
- rate control
- anticoagulate 4-6wks then cardiovert
- anticoagulate x6wks after successful cardioversion or indefinately if pt unaware they were in afib.
…..if failure of CV and medical therapy:
atrial ablation, AV ablation in extreme cases which would require pacemaker placement.
What is the CHADS2 calculator? what is it used for?
CHADS2 is used to estimate embolic risk, does not apply to those with valve dz.
C=CHF 1pt H= HTN 1pt A=Age greater than 75 1pt D=DM 1pt S=stroke 2pts
*if equal to or greater than 2pts anticoagulation unless CI.
Evaluation of new onset afib pts
-echo: evaluate presence of valvular heart disease
Nuclear stress test: evaluate presence of ischemic heart dz
SLeep study: r/o sleep apnea
Thyroid function test*****
Atrial Flutter
- rate
- rhythm description
- ekg findings
- tx
Rate: atria=250-350BPM
ventricles=150
Rhythm: regularly irregular, AV node blocks at 2:1, 3:1. 4:1
EKG:
-sawtooth pattern
Tx: ASA 325mg/day -ablation if failed cardioversion and medical therapy -Class 1A antiarrhythmics to convert back to sinus: Pronestyle (Procainmide) -Ventricular rate controlled with: --beta blocker --calcium channel blocker --digoxin
What are the AV node disturbances
- Junctional Escape
- Accelerated Junctional
- Junctional Tachy
Junctional Escape &Accelerated Junctional
- rate
- EKG findings
- tx
Rate:
-Junctional escape: 40-60BPM
-Accelerated Junctional:
60-100BPM
EKG findings both:
- Narrow QRS complex
- Retrograde P wave (inverted with short PR interval), P wave immediately after QRS, or no P wave
Tx:
no tx required
Junctional Tachycardia
- rate
- tx
Rate: 150-250BPM
Tx: Acute:
- vagal maneuvers
- adenosine (DOC)*
Long Term:
- beta blockers
- calcium channel blockers
- Class 1A, 1C, and III antiarrhythmics for resistant cases
What are the types of AV Blocks?
- 1st degree
- 2nd degree Wenkebach
- 2nd degree Mobitz
- 3rd degree heart block
1st degree AV block
- tx
- ekg findings
tx: treat the underlying cause (such as inferior MI, digitalis tox, hyperkalemia, myocarditis, rheumatic fever)
-ekg findings:
consistently prolonged PR interval greater than 0.20
