Dysrhythmias originating Sinus Node (NSR) Bradycardia (SVT ...

Normal Sinus Dysrhythmias originating Sinus Node Dysrhythmias originating in the Atria
Rhythm
Rhythm (NSR) Sinus Sinus Sinus Arrhythmia Premature Atrial Atrial Flutter Atrial Fibrillation Supraventricular
Tachycardia Bradycardia Complex (PAC) (A-fib) Tachycardia
Rate 60 - 100 (SVT)
bpm > 100 < 60 60 – 100 Depends on rate of May be Normal/Tachy Usually Tachy
Regularity Regular Regular Regular underlying rhythm > 150
Normal/Upright/ Frequently: Atria - Regular Irregular
P wave Irregular whenever a Ventricles - Reg or Irreg Regular
P-R Rounded Ç w/inspiration PAC occurs Sawtooth pattern on P No true P waves;
interval 0.12 – 0.20 sec È w/expiration chaotic atrial activity P waves hidden
QRS P wave is present; waves. or not present
< 0.12 sec Irregular; in PAC may have More P waves than Absent
Drugs < 0.12 sec Absent
n/a varies w/respiration different shape QRS Amiodarone < 0.12 sec
Amiodarone
Normal/Upright/ Normal/Upright/ Normal/Upright/ Varies in PAC, Variable
Rounded Rounded Rounded otherwise normal The rate is so fast
< 0.12 sec that the P waves
0.12 – 0.20 sec 0.12 – 0.20 sec 0.12 – 0.20 sec < 0.12 sec may not be seen. It
may be related to
< 0.12 sec < 0.12 sec < 0.12 sec caffeine intake,
Treat the If symptomatic: Do NOT require tx nicotine, stress, or
underlying Atropine unless anxiety in healthy
cause, i.e. fluid Epi 1:10,000 accompanied by adults.
replacement, slow heart rate that
relief pain, causes blood flow
reduce fever,… compromise, if so
admin Atropine

A normal ECG May be caused It is normal in The SA node Stimuli originates Its presence may be the Rapid, erratic electrical
does not by exercise, athletes and during discharges within atria, but not in first indication of cardiac discharge comes for
exclude heart anxiety, fever, sleep. In acute MI, irregularly. The the SA. disease. multiple points in the atria
disease hypoxemia, it may be protective pacing rate varies
hypovolemia, or and beneficial of w/respiration, In patients w/heart s/s depend on => ineffective atrial
Clinical cardiac failure. the slow rate may especially in disease, frequent ventricular response contraction =>
Tip compromise children and elderly PACs may precede rate. Èstroke volume
It is the response cardiac output. people. paroxymal SVT, A-fib, Ècardiac ouput
to the body’s Certain or A-flutter. It is usually a chronic
demands for medications, such arrhythmia associated
increase O2. as beta blockers,
may cause it. w/heart disease.
s/s depend on ventricular
response rate.

Dysrhythmias originating in the AV Junction

Rhythm 1st Degree AV 2nd Degree AV 2nd Degree AV 3rd Degree AV Junctional Accelerated Junctional Premature
Rate Block Block (Type 1) Block (Type 2) Complete Heart Block Junctional Tachycardia Junctional
bpm Complex (PJC)
60 – 100 Mobitz I or Mobitz II 40 – 60 40 – 60 60 – 100 > 100
Regularity Wenckebach < 60 (Brady) Regular Depends on rate of
Regular Normal or Brady Atria- Reg. (60-100) Regular Regular underlying rhythm
P wave Irregular Vent.-Reg.(40-60)
Normal/Upright/ Irregular Irregular
P-R Rounded But atria and whenever a PJC
interval ventricles act
QRS > 0.20 sec independently occurs
< 0.12 sec
Drugs Normal/Upright/ Normal/Upright/ Normal/Upright/ P waves absent, P waves absent, P waves absent, P waves absent,
Rounded Rounded Rounded inverted (bcos inverted (bcos inverted (bcos inverted (bcos
signal comes signal comes from signal comes from signal comes
Lengthening until More P waves None from junction), or junction), or buried junction), or buried from junction), or
beat is dropped than QRS Atria independent of
buried None or None or buried
< 0.12 sec Normal or long on Ventricles Short (< 0.12 sec) Short (< 0.12 sec)
conducted beats < 0.12 sec None or None or
Short (< 0.12 sec) < 0.12 sec < 0.12 sec Short (< 0.12 sec)
< 0.12 sec
< 0.12 sec < 0.12 sec
No tx if
asymptomatic.

Amiodarone and Lidocaine are CONTRAINDICATED for
2nd and 3rd degree blocks!!!

This rhythm may Each QRS has P It is like a NSR, It is like a NSR, but: s/s of decreased It looks like PAC,
be caused by meds wave in the same but: - no P waves cardiac output may but it doesn’t have
such as beta place. But there - no P waves be seen in response P wave!
blockers, digoxin, are more P waves - 40-60 bpm to the rapid rate.
and calcium than QRS.
Clinical channel blockers.
Tip Ischemia involving Often occurs
right coronary w/cardiac ischemia
artery is another or an MI.
cause.

Dysrhythmias originating in the Ventricles

Trigeminal PVCs: Ventricular Tachycardia Bundle Branch Accelerated Asystole
every 3rd beat is a (3 or more consecutive Idioventricular
Rhythm Ventricular Fibrillation Blocks Idioventricular
PVC. PVCs beats)
Rate Depends on rate of > 100 (BBB)
bpm underlying rhythm
Regularity Irregular whenever a Regular Rapid/Chaotic (300-600) Depends on rate of 20-40 > 40 0
underlying rhythm
P wave PVC occurs No P waves
P-R No P wave Extremely Irregular Regular Regular Regular na
interval associated w/the PVC na
No P waves Normal/Upright/ No P waves No P waves No P waves
na Rounded
na na None
Normal (0.12 – 0.20
sec) > 0.12 sec (wide)
(This is the main
QRS > 0.12 sec (wide) / > 0.12 sec (wide) > 0.12 sec (wide) / > 0.12 sec (wide) difference w/Junctional > 0.12 sec (wide) None
Bizarre Bizarre (This is the main difference
rhythm) Epi 1:10,000
w/Junctional rhythm) Atropine

Lidocaine Pulseless: Pulse: Epi 1:10,000
w/malignant PVC’s Epi 1:10,000 Lidocaine Amiodarone
(ensure HR > 60bpm Amiodarone Lidocaine
Drugs and BP > 90 too) Lidocaine

Look at underlying It is important to confirm the This is a shockable The signal originates It is also called Agonal Idioventricular rhythms Always confirm
rhythm. Can appear in presence or absence of rhythm. at the Atria => there rhythm. appear when Asystole by checking
couplets, triplets, or pulses bcos VT may be There is no pulse or are P waves, but the supraventricular pacing the ECG in 2 different
short runs of VT. Can perfusing or not perfusing. cardiac output. Rapid block is in the bundle sites are depressed or leads.
be multi-focal or uni- intervention is critical. branch on the way absent. Diminished cardiac
focal. Caused by This is a shockable rhythm, down to the ventricle, output is expected if the Total absence of
random firing within the therefore before shocking the Because artifact can => you can see the heart rate is slow. ventricular electrical
ventricles. No atrial patient, check if there is a mimic VF, always block within the QRS. activity, therefore:
Clinical firing => no P wave. pulse: check patient’s pulse - no ventricular rate
Tip Patients may sense the - If pulse => do NOT shock before beginning Commonly occurs in - no pulse
occurrence of PVCs as - If NO pulse => Shock treatment for VF!!! coronary artery - no cardiac output
skipped beats bcos the disease.
ventricles are partially
filled; the PVC If atrial electrical
frequently doesn’t activity present, it is
generate a pulse. called ‘P-wave’
asystole.