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)
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
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
Third-degree AV block (complete block)
rate around 40's
- no relationship b/t P waves and QRS complexes (QRS slower than P rate)
- P-P reg (atrial reg) & R-R reg (vent reg)
but NOT connected (i.e P-R inconsistent)
- WIDE QRS
always serious and dangerous
Asystole
- dead
- no electrical activity, only straight line (no rate/pulse)
A dire form of cardiac arrest in which the heart stops beating -- there is no systole -- and there is no electrical activity in the heart. The heart is at a total standstill.
Premature ventricular contractions (PVC's)
Wide QRS
- may be unifocal or multifocal
- will have compensatory pause
- irreg rythm PVCs may be bigeminy, trigeminy, or quadrigeminy
- "run of" PVCS
- 3+ PVCs = Vtach!
Idioventricular rhythm
<40
looks like vtach but slow
- no P waves (from vent foci)
- Wide QRS
(serious, death like rhythm)
- called "dying heart" rhythm...occasional ventric beat b4 death (asystole)
Accelerated idioventricular rhythm (AIVR)
40-120
- occur in short burst, usually following MI
- mostly asx with no progression to vtach / vfib
Ventricular tachycardia
150-250 (>120 from onysko)
- ventricle irritated and moving fast
- rapid, bizarre, wide QRS complexes
- 1 large QRS after another!
(in vtach pt may not have pulse)
Ventricular Flutter
250-350
- smooth sine-waves w/ similar amp
- can lead to deadly arryth
goes right into vfib
Tosades de Pointes
Flutter 250-350
- type of vtach, can lead to vfib
- ribbon like fashion (hallmark: up and downward deflection of QRS)
- d.t hypomagnesium
Ventricular Fibrillation
350-450
- "chaotic"
- mult vent foci rapidly discharging -> erratic vent rhythm
- no identifiable waves
- RESPOND IMMEDIATELY!
- no pulse or perfusion, pt=dead
R atrial hypertrophy
tall P waves! (in lead II, III, and aVF)
- > 2.5 boxes
cause: pulm HTN, COPD, Pulm emboli
L atrial hypertrophy
I --> wide P wave (biphasic)
V1 --> P wave up & down like an S (terminal negativity)
R ventricular hypertrophy (RVH)
- tall R wave in V1 (inverted T here too)
- R gets progressively smaller as we go from V1-V4
- normally V1 has long S wave so looks like big V, when that is not the case think RVH
causes: Pulm HTN
(not too common)
L ventricular hypertophy (LVH)
V1 --> deep/long S wave
V5/6 -> tall/high R wave
count boxes together if >35 LVH
causes: systemic HTN, aortic stenosis, mitral insuffic
(very common)
BBB
- Wide QRS >3 box
- 2-R waves "bunny ears"
A block in the Bundle Branch produces a delay in depol of the ventricle that it supplies
(note: can't read ischemia b/c BBB distort this)
if have L & R BBB = complete block
R Bundle Branch Block
- wide QRS >3 boxes (0.12)
- V1/V2 "bunny ears" (2-R waves)
(V1/2/3 all up)
- common, doesn't have much path assoc
L Bundle Branch Block
- wide QRS >3 boxes (0.12)
- V5/V6 "bunny ears" (2-R waves)
(V1/2/3 all down)
- not as common, more patho
Myocardial Infarction (MI)
Ischemia: inverted Twave
Injury: ST seg elevation
Necrosis: Q wave present
- area of infarct doesn't conduct electrical activity
- infarction=cell death
(A MI (heart attack is) when blood vessels that supply blood to the heart are blocked, preventing enou
Ischemia
- T wave inversion
- Ischemia is caused by a decrease in oxygen to the myocardial tissue (hypoxia/diminished blood supply)
- can still save heart cells/reverse
Injury
ST segment elevation (a sign of acute injury going on presently) (look for sad face)
- Injury indicates the acuteness of an infarct (acute or recent)
- can still save heart cells/reverse
Necrosis
significant Q waves
(?than 1 square wide or ?1/3 amplitude)
- indicated by Q-waves which make the dx
- Infarction is completed, now dead tissue
(canNOT be reversed, permanent damage)
anterior wall
V1, V2, V3, V4
- occlusion of anterior descending coronary artery
Anteroseptal region
V1, V2
Inferior wall
II, III, aVF
- occlusion of right or left coronary artery
Lateral wall
I, aVL and V5, V6
- occlusion of circumflex artery
Posterior wall
since no post lead look in V1 for unusually large R wave
- occlusion of right coronary artery
Angina pectoris
...
Unstable angina
...
Digitalis Effect
- shortened QT interval
- characteristic down-sloping ST depression (SCOOPING ST seg)
Hypercalcemia
Short/absent QT segment
(tooo healthy --> short QT (skinny))
Hypocalcemia
(not healthy (not taking vit like Ca++) so look like a hipo which is large -> long QT)
Hyperkalemia
tall, peaked and narrow T
severe --> flattening of P wave, wide QRS, and tall T='sine wave'
Hypokalemia
- flat T present
- depressed ST seg
- U wave to prominent U wave
Lown-Ganong-Levine Syndrome
AV node by passed, so short PRI
P adjacent to QRS
Pacemakers
pacemaker spike (may be small; sometimes missed)
- not supraventricular so wide QRS
Pericarditis
ST segment elevated in ALL leads
T wave: may be elevated off the baseline
Pulmonary embolus
(S1 Q3 T3)
Lead I: wide S
Lead II: ST depression
Lead III: large Q and Inverted T
V1-V4: inverted T waves
Acute right BBB
Wolf-Parkinsons-White
- P wave is immediately followed by short delta wave
- slurred upstroke on wide QRS w/ short or no PRI
- common condition can lead to parox tachy
(ppl born w/ extra fibers)
Axis
Refers to the direction of movement of depolarization
- Look in leads I and AVF
- I-left, AVF-right
Thumbs:
- both up = Normal axis
- both down = Extreme right axis deviation
- Lup/Rdown = Left axis deviation
- Rup/Ldown = Right axis deviation
- Specific
Axis pic
Wide QRS
Vtach, PVC, 3o AV block, BBB
Rate 40's
3o AV block, 2o AV block type II, or ventricular rhythm