Exam 1 - Dysrhythmias (4.6)

P wave: depolarization of the atria (atria contracting)

QRS wave: ventricular depolarization (ventricles contracting), ventricular contraction occurs at peak of the R

T wave: ventricular repolarization (ventricles relax)
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Terms in this set (34)
premature arterial contraction (PAC)premature contraction arrhythmia in which atria contract earlier than they shouldPremature Junctional Contractionpremature contraction Inverted p wave or hidden p wavepremature ventricular contraction (PVC)premature contraction a ventricular contraction preceding the normal impulse initiated by the SA node (pacemaker) (QRS are very wide >.12 seconds)Atrial Fibrillation•Irregularly irregular •No discernable p wave • Atrial rate 350-600 bpm- Heart disease - HTN - lung disease - electrolyte imbalance (K+ and MG++) - thyroid disease - advanced ageAtrial Fibrillation associated with (6):- Slow ventricular response (amiodarone, calcium channel blockers, beta blockers, digoxin) - Convert to sinus rhythm (synchronized cardioversion, chemical cardioversion) *If in afib >48 hours, must be anticoagulated before, ablationAtrial Fibrillation treatmentatrial flutter•Usually regular with multiple p waves for each qrs •Flutter waves give sawtooth appearance to rhythm • Atrial rate 200-350 bpmAssociated - Heart disease - HTN - lung disease - PE - electrolyte imbalance (K+ and MG++) - thyroid disease - medications Treatment - Slow AV conduction of impulses to the ventricle with calcium channel blockers and beta blockers - electrical cardioversion, antiarrhythmics, ablationAtrial Flutter Associated with TreatmentFirst degree AV block•Criteria for First Degree AV Block •Looks like NSR but the PR interval is longer (prolonged interval between SA node firing and depolarization of the ventricles) • PR interval >0.20 • P wave precedes each QRS complex •QRS complex shape unchangedAssociated - Age - MI - CAD - electrolyte imbalances - vagal stimulation - medications Treatment - No treatment necessary - correct electrolyte imbalance - be alert for advancing blockFirst degree AV block Associated with TreatmentSecond Degree AV Block Type I•Also called Mobitz type I or Wenckebach •Atrial rhythm regular, P-to-Ps equal •Ventricular rhythm irregular and slower than atrial rhythm, R-to-Rs not equal •P wave precedes each QRS complex but QRS does not proceed P wave •PR interval progressively lengthens until P wave goes non-conducted and it is not followed by QRS complex •QRS complex shape unchanged, QRS normalAssociated - drugs such as digoxin, beta blocker - ischemic heart disease Treatment - If symptomatic may use atropine. - Monitor for advancing block. - Transcutaneous or transvenous pacemaker may be necessary.Second Degree AV Block Type I Associated with TreatmentSecond Degree AV Block Type II•Also called Mobitz type II •PR interval does not change and usually is normal duration or slightly lengthened •P wave precedes each QRS complex but not all p waves are followed by a QRS complex •P, T and QRS complex shapes unchanged •Atrial rhythm regular; ventricular rhythm irregularAssociated - Rheumatic heart disease - CAD - anterior MI - drug toxicity Treatment - Transcutaneous or transvenous pacemaker may be necessary before permanent pacer if condition does not resolve. - Monitor for advancing block.Second Degree AV Block Type II Associated with TreatmentThird Degree AV Block•Also called Complete Heart Block •No relationship between P waves and QRS complexes •Atrial rate regular 60-100 •QRS complex shape normal or wide & bizarre •Ventricular rate usually rate 20-40Associated - CAD - MI - myocarditis - cardiomyopathy - drugs Treatment - Transcutaneous or transvenous pacemaker until permanent pacer is placed. - Dopamine and epinephrine may be used if temporary pacemakers are not available or effective.Third Degree AV Block Associated with TreatmentFirst degree wenckeback mobitz II third degreeIf the R is far from P then you have ______ degree Longer, longer, longer, drop? Then you have a _______ If some Ps don't get through then you have ______ If Ps and Qs don't agree, then you have a _____ degreeSupraventricular Tachycardia (SVT)•HR 151-220 bpm •Regular or slightly irregular rhythm •P wave may be hidden by preceding T wave •QRS complex shape normalAssociated - Overexertion - emotional stress - deep inspiration - stimulants - rheumatic heart disease - digitalis toxicity - CAD - cor pulmonale Treatment - vagal stimulation - adenosine - beta blockers - CCB - if unstable: cardioversionSupraventricular Tachycardia (SVT) Associated with Treatment1) AV node, re-entry 2) chest pressure 3) heart, 1-2 seconds, 20mL 4) asytoleAdenosine 1) slows _____ _____ conduction, interrupts _______ pathway 2) explain to the client that there may be some _____ _____ with administration 3) inject as c;ose to the _____ as possible, rapidly over ______ seconds followed quickly with ______ saline 4) be prepared for short period of ____ventricular tachycardia•Ectopic foci take over SA node as pacemaker •Ventricular rate 150-250 bpm •Monomorphic, polymorphic, sustained, and non-sustained •Stable vs unstable- pulse and pulseless •Life threatening because of decreased CO and possibility to turn into V fibAssociated - MI - CAD - electrolyte imbalances - cardiomyopathy - drug toxicity - CNS disorders Treatment - If stable with pulse: treat cause, amiodarone, lidocaine, procainamide; polymorphic with prolonged baseline QT - IV magnesium, isoproterenol, phenytoin - cardioversion - pulseless: CPR, defibrillation, epinephrine, amiodaroneVentricular Tachycardia Associated Treatmentventricular fibrillation•Multiple ectopic foci in the ventricles •Ventricle quivering •No CO, no pulseAssociated - Acute MI - cardiomyopathy - HF - electric shock - hyperkalemia - hypoxemia - acidosis - drug toxicity Treatment - CPR, defibrillation, epinephrine, amiodaroneVentricular fibrillation Associated Treatment