Flashcards in Arrhythmias Deck (34)
What are the sinus node rhythm disturbances?
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
-atropine IV if hemodynamic instability
Sinus Bradycarida what is this? Tx
heart rate less than 60BPM, may be caused by beta blockers and digoxin
-sx & hemodynamically unstable: atropine &/or temporary pacemaker
monitor and educate
-no tx for long term if pt is asymptomatic
-will need permanent pacemaker if sx
-what is this?
What: heart rate greater than 100BPM
fever, pain, exercise, anemia, hypotension, thyrotoxicosis, anxiety
-treat underlying cause
-calcium channel blockers (cardizem and verapamil)
What are the supraventricular arrhythmias
--AV node re-entrant tachy (shortcut)
-medications to prevent recurrence
-P wave buried in QRS
-QRS is narrow** and normal morphology
-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
-what causes this
-what is it
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 .
palpitations, tachycardia, dizzines, dyspnea, anxiety, syncope, cardiac arrest.
-PR interval is short, less than 0.12ms, Delta wave*
-IV adenosine OR IV cardizem or verapamil if adenosine doesnt work.
-if hemodynamically unstable cardioversion
Paroxysmal Atrial Tachycardia (PAT)
-what is this?
-may conduct to ventricles but the AV node will try to block impulses
-P wave morphology varies from sinus*
-Treated with Vagal Maneuvers
-if Vagal maneuvers fail...
--Calcium channel blockers to prevent recurrence
Premature Atrial Contractions (PACs)
-what causes this?
Cause: discharge from a non-sinus atrial pacemaker
-p-wave preceding may not look like the p waves that originate from sinus node, may get lost in T wave.
-non-life threatening, only treat if symptomatic w/ beta blockers.
Wandering Atrial Pacemaker
-P wave; needs to have 3 distinctly different P waves
Tx: no tx required
Multifocal Atrial Tachycardia
Rate: greater than 100
-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
-describe this rhythm
-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"
-no distinguishable P waves
Common w/ vavlular dz, heart failure, HTN, and sleep apnea.
What is the most common encountered arrhythmia in clinical practice?
Which lab always needs to be checked with new onset of Afib dx?
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.
-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:
-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.
H= HTN 1pt
A=Age greater than 75 1pt
*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*****
Rhythm: regularly irregular, AV node blocks at 2:1, 3:1. 4:1
-ablation if failed cardioversion and medical therapy
-Class 1A antiarrhythmics to convert back to sinus: Pronestyle (Procainmide)
-Ventricular rate controlled with:
--calcium channel blocker
What are the AV node disturbances
Junctional Escape &Accelerated Junctional
-Junctional escape: 40-60BPM
EKG findings both:
-Narrow QRS complex
-Retrograde P wave (inverted with short PR interval), P wave immediately after QRS, or no P wave
no tx required
-calcium channel blockers
-Class 1A, 1C, and III antiarrhythmics for resistant cases
What are the types of AV Blocks?
-2nd degree Wenkebach
-2nd degree Mobitz
-3rd degree heart block
1st degree AV block
tx: treat the underlying cause (such as inferior MI, digitalis tox, hyperkalemia, myocarditis, rheumatic fever)
consistently prolonged PR interval greater than 0.20
2nd Degree Wenckebach
-where does this block occur?
Tx: no tx, since generally no sx
-Block occurs in AV node and bundle of HIS
EKG: PR interval gets progressively longer until a QRS is dropped
2nd degree AV block Mobitz Type II
-where does this block occur?
- EKG findings
-This block occurs below the bundle of his
-EKG findings: "out of the blue drop a Q", usually widened QRS
Tx: atrial pacing, permanent pacemaker
3rd Degree AV heart block
EKG: atrial rate is normal, normal P-P intervals, but not married to QRS intervals.
-QRS may be normal or widened
-atria faster than ventricles, ventricles around 70BPM
-external pacing and atropine for acute symptomatic episodes
-permanent pacing for chronic complete heart block.
What are the ventricular dysrthmyias
-Premature ventricular contraction
Premature Ventricular Contractions
-Sustained VT is how long? Nonsustained?
causes: KNOW THESE, Jen said so...
-Hypokalemia, low magnesium level, increasing catecholamines, coronary ischemia
-P wave usually obscured by QRS
-QRS is wide, morphology is bizarre
-Sustained VT if greater than 30seconds or nonsustained if less than 30seconds.
-PVCs may occur in singles, couplets(2 in a row), or triplets, or in bigeminy(every other is PVC), trigeminy(every 3rd is PVC), or quadrigeminy
-Lidocaine Class 1B antiarrhythmic
-Rocainamide Class 1A
-Amiodarone Class III
-cardioversion & amiodorone
-defibrillation & amiodarone
****LIFE THREATENING ARRHYTHMIA!!!***