EKG Rhythms Questions and Answers Already Passed

EKG Rhythms Questions and Answers Already Passed Normal Sinus Rhythm 60-100 bpm all complexes normal and evenly spaced (P, QRS, T) Sinus Arrest - SA node doesn't fire - notice absence of P-wave for a complete cycle (a missed cycle) 00:0201:28 Sinus arrhythmia all complexes normal but rhythmically irreg - normal finding (esp in young pts) that has to do with breathing (rate: inhale-increase, exhale-decrease) Sinus Bradycardia 60 normal sinus rhythm Sinus Tachycardia 100 (100-150) normal sinus rhythm Wandering atrial pacemaker Hint: try never to pick this - impulse originate from varying points in atria - variation in P wave contour, PR-I, PP-I and thus RR-I P wave vs T wave P generally smaller than T MAT (multifocal atrial tachy) - impulse originates at diff places in atria so P waves diff and intervals might not be consistent - assoc w/ severe pulm dz Atrial Fibrillation A: 350-450 (atria quivering) - irreg-irreg rhythm (R-RI=irreg) *unsure/no P-wave (non-distinguishable)* - irreg rhythm BUT reg QRS! Danger: increase the risk of thromboemoblic events don't convert unless occurring less than 48 hrs, if don't know pt need to be put on thrombolytics) Atrial Flutter A: 250-350 - "saw tooth" p-waves - a continuous rapid sequence of atrial complexes from a single rapid-firing atrial focus (hint: if see 2 P waves and QRS think A Flutter) Junctional Escape beats retrograde atrial depolarization P' is inverted Junctional rhythm 40-60 Regular! -impulse from AV node w/ retro/antegrade transmission - P wave often inverted/buried/follow QRS - slow rate - narrow QRS (not wide like ventricular) Junctional Tachycardia 60 bpm (ms. K; 150-250) - KEY: will be regular (consistent) - AV junction produces a rapid sequence of QRS-T cycles - p-wave often inverted/buried/follow QRS Premature junctional contractions (PJC) - premature slightly widened QRS - +/- inverted P', before or after QRS, sometimes disappears w/in QRS Premature atrial contractions (PAC's) - originates suddenly in irritable atrial foci - P' is earlier than expected and diff shape than P (often have a pause following PAC) - can occur in Bigeminy, Trigeminy, Quadgeminy pattern Supraventricular Tachycardia (SVT) aka Paroxysmal atrial tachycardia (PAT) 150-250 "sudden rapid heart rate" - an irritable atrial focus discharging - very fast and EVEN! - +/- inverted P waves - P often overlaps prior T wave First-degree AV block - PRI 5 boxes/.20 sec - Fixed but prolonged PRI (consistent but long) - normally get bradycardia here Second-degree block: Mobitz Type I Wenckebach) "walk it back" - PRI gradually lengthens then drops QRS "grouping and then a miss" - typically pattern exists (constant P-P interval, QRS is what is moving back) - not really serious or dangerous Second-degree AV block: Mobitz Type II - normal PRI then sudden drop of QRS - P wave doesn't always produce QRS - P-R interval is constant (diff from 3rd degree) - no hint just drops out - is serious and dangerous pt needs tx! - tend to be every other, so drops HR by 1/2) -- def bradycardia (rate=40bpm) Third-degree AV block (complete block) rate around