QUICK EKG REFERENCE

NORMAL SINUS RHYTHM

EKG CriteriaRate: 60-100 bpm.Rhythm: Regular.

P wave: look the same PRI: .12-.20 secondsQRS: .08-.12 seconds

narrow unless effected by underlying anomoly

SINUS BRADYCARDIA

EKG CriteriaRate: <60 bpm.

Rhythm: Regular generally.Pacemaker: SA node

P wave: Present, all originating from SA node, all look the same.PRI: <.20 seconds and constant.QRS: Normal, .08-.12 seconds

SINUS TACHYCARDIA

EKG CriteriaRate: >100 bpm.

Rhythm: Regular, generally.Pacemaker: SA node.

P wave: Present and normal, may be buried in T waves in rapid tracings.PRI: .12-.20 seconds, generally closer to .12

QRS: Normal.

SINUS ARRHYTHMIA

SINUS EXIT BLOCK

R-R irregularP-P irregular

P before & for every QRSPRI: .12-.20 secondsQRS: .04-.12 seconds

SINUS ARREST

R-R irregularP-P irregular

P before & for every QRSPRI: .12-.20 secondsQRS: .04-.20 seconds

Missing PQRS complex

SICK SINUS SYNDROME

Electrocardiogram exhibiting alternating patterns of bradycardia and tachycardia as seen in patients with sick sinus syndrome

ATRIAL RHYTHMS

PREMATURE ATRIAL CONTRACTION

EKG CriteriaRate: Underlying rhythm.

Rhythm: Irregular with PACs.Pacemaker: Ectopic atrial pacemaker outside SA node.

P wave: Ectopic P wave present, generally different than normal SA P wave.PRI: Generall normal range 120-200 msec,

but differ from underlying rhythm.QRS: Same as underlying rhythm

ATRIAL FIBRILLATION

EKG CriteriaUndulating baseline replaces P waves

Rhythm: Irregularly irregular

ATRIAL FLUTTER

EKG Criteria Rate: 250 - 350 bpm (atrium)Rhythm: Atrial rate regular,

ventricular conduction 2:1 to 8:1Pacemaker: Reentrant circuit rhythm located in the right atrium

P wave: Saw-tooth or picket fencePRI: Constant onset

CARDIOVERSION

Cardioversion was done to convert Atrial Flutter to Sinus Rhythm

ATRIAL TACHYCARDIA

P before & every QRSPRI: .12-.20 seconds

QRS: .08-.12Can come in runs or bursts

MULTIFOCAL ATRIAL TACHYCARDIA-MAT-WAP

R-R may be a little irregular due to different foci in atrial conductionP-P may be a little irregular due to different foci in atrial conduction

P before & for every QRS of underlying rhythmDifferent shaped P waves due to changes in conduction foci

PRI: usually within .12-.20 secondsQRS: 04.-.12 seconds

Different shaped P waves due to changes in conduction foci

JUNCTIONAL RHYTHMS

JUNCTIONAL RHYTHM

EKG CriteriaRate: 40 - 60 bpmRhythm: Regular

Pacemaker: Atrioventricular junctionP wave: If present, negative in lead 2

PRI: .12 seconds or lessQRS: .08-.12 seconds, unless prolonged by aberrant conduction

JUNCTIONAL TACHYCARDIA

R-R regular; rate >100

P-P regular; rate >100 (may or may not have visable P at fast rateP wave inverted, my come before, during or after QRS

If P is with T, it will NOT peak the T

PREMATURE JUNCTIONAL CONTRACTION

EKG CriteriaRate: Underlying rhythm

Rhythm: Irregular with PJC'sPacemaker: Ectopic junctional pacemaker

P wave: If present, negative in Lead 2PRI: .12 seconds or less

QRS: .08-.12 seconds, unless prolonged by aberrant conduction

HEART BLOCKS

FIRST DEGREE AVB

EKG CriteriaRhythm: RegularPRI: >.20 seconds

SECOND DEGREE-MOBITZ II

EKG CriteriaPRI: Constant on conducted complexes until a sudden block of AV conduction.

That is, a P wave is abruptly not followed by a QRS

SECOND DEGREE-WENCHEBACH-MOBITZ I

EKG CriteriaRhythm: Irregular

PRI: Progressive lengthening of PRI until dropped beat.A clue to Wenckebach is that the QRS's appear to occur in groups

THIRD DEGREE AVB

AV DISSOCIATIONThere is no fixed temporal relationship between P waves and QRS complexes

due to the existence of two independent pacemakers,one in the SA node (or in the atria) which controls the beating of atria

and other in the AV junction (or in the ventricles) which controls the beating of ventricles. When the atria are beating faster than the ventricles,

AV dissociation is due to complete AV block; when the ventricles are beating faster than the atria,

AV dissociation is due to ectopic tachycardia (junctional or ventricular). In complete AV dissociation no atrial impulse is conducted to the ventricles;

in incomplete AV dissociation some atrial impulses may be conducted to the ventricles resulting in ventricular captures.

RIGHT BUNDLE BRANCH BLOCK

When the right bundle branch is blocked, activation of the right ventricle begins when electrical activity “spills over” from the left

ventricle.Depolarization of the right ventricle is delayed.

The QRS is prolonged (over 0.1 sec) in right bundle branch block (RBBB).This extra length of the QRS is caused by late activation of the right ventricle,

which is then seen after the left ventricle activity.Normally, right ventricle activity is not seen,

as it is overshadowed by the larger left ventricle.In RBBB, a typical RsR’ wave occurs in lead V1.

Also, a wide S wave is seen in leads I, V5, and V6, along with a broad R in lead R. When RBBB occurs in a patient with old or new septal infarction,

the initial septal R wave may not be seen in lead V1.Instead, a wide QR complex is seen.

When the typical RsR’ wave is seen in V1 without widening of the QRS complex, this is called “right ventricular conduction defect” rather than RBBB

LEFT BUNDLE BRANCH BLOCK

LBBB usually indicates widespread cardiac disease.When the left bundle is blocked,

activation of the left ventricle proceeds through the muscle tissue,

resulting in a wide (.12 msec) QRS complex.In left bundle branch blockage (LBBB),

the QRS usually has the same general shape as the normal QRS,but is much wider and may be notched or deformed.Voltage (height of the QRS complex) may be higher.

In LBBB, look for wide (possibly notched) R waves in I, L, or V5-V6,or deep broad S waves in V1-V3.

There is left axis deviation.“Septal Q waves” sometimes seen in I, L, and V5-V6 disappear in LBBB.

T waves in LBBB are usually oriented opposite the largest QRS deflection.That is, where large R waves are seen,

T waves will be inverted. ST segment depression may occur.

SUPRAVENTRICULAR TACHYCARDIA(SVT)

EKG CriteriaRate: 140 - 220 bpm

Rhythm: RegularPacemaker: Reentry circuit

Accessory pathway: Normal or short (if down accessory pathway)A-V nodal reentry: Hidden in or at end of QRS

PRI: Depends on location of circuitQRS: Normal if accessory pathway used - prolonged (>120 msec) with delta wave

QRS ETIOLOGY SVT vs VT

VENTRICULAR RHYTHMS

PREMATURE VENTRICULAR CONTRACTION

EKG CriteriaRhythm: Irregular

QRS: Is not normal looking. Broadened, greater than 0.12 seconds. P waves are usually obscured by the QRS, ST segment, or T wave of the OVC.

The P wave may sometimes be seen as notching during the ST segment or T wave.

BIGEMINY

EKG Criteria QRS: Normal QRS complex followed by (PVC) in patterns of 2

VENTRICULAR ESCAPE BEAT

VENTRICULAR TACHYCARDIA

EKG CriteriaNo normal looking QRS complexes, often bizzare with notching.

Width of QRS>0.12 sec. ST segment and T wave are opposite polarity to the QRS.

Sinus node may be depolarizing normally. There is usually complete AV dissociation.

P waves are sometimes seen between QRS complexes. They have no impact on the QRS complexes.

Rate: Generally 100 to 220 bpmRhythm: Generally regular, on occassion can be modestly irregular.

TORSADES

P wave obscured if presentQRS wide and bizarre morphology

Conduction as with PVCs Rhythm Irregular

Paroxysmal–starting and stopping suddenly The upward and downward deflection of the QRS complexes around the

baseline.The term Torsade de Pointes means "twisting about the points."

ASYSTOLE

EKG CriteriaComplete absence of ventricular electrical activity.

Occasional P waves or erratic ventricular beats may be seen. These patients will be pulseless.

Treatment must be immediate if the patient is to have any chance at resusctiation.Rate: None

Rhythm: None

Sometimes there is a few or more seconds of Asystole as in the above strip of over 5 seconds.

IDIOVENTRICULAR

EKG CriteriaRate: 40 bpm

Rhythm: Regular P wave: Regular if present

PRI: If present, varies (no relationship to QRS complex [AV dissociation])QRS: QRS interval >.12 seconds wide and bizarre

VENTRICULAR FIBRILLATION

EKG Criteria

Rate: Very rapid, too disorganized to count.Rhythm: Irregular, waveform varies in size and shape

No normal QRS complexes.Absent ST segments, P waves, T waves.

PACERS & ICD

VENTRICULAR PACED

Note the pacemaker spikes before the QRS complexes.

ATRIAL PACED

Pacemaker spikes are seen before each QRS complexand initiate a tiny P wave

MVP OPERATION

NON-CAPTURED PACED

Paced rhythm with single failure to capture

PACER FAILURE

ATRIAL-VENTRICULAR PACED

ICDBelow are 2 ways for Ventricular Tachycardia

to be terminated having a ICD.

Ventricular Tachycardia with ICD pacer overriding the VT rate to convert back to sinus rhythm

Ventricular Tachycardia with ICD firing (without the pacer override) conversion.

AGONAL RHYTHM

Hyperkalemia with Agonal RhythmThe QRS complexes here are ventricular escape beats

as noted by the severe bradycardia (inherent ventricular rate in the 40s),wide complex indicating origin is in the ventricle, and lack of a preceding p-wave