Sinus Bradycardia
Rate-less than 60 Rhythm-regular Pacemaker Site-SA node P waves-upright and normal in morphology PR interval-normal (0.12-0.20 sec and constant) QRS complex-normal (0.04-0.12 sec)
Sinus Tachycardia
Rate-Greater than 100 Rhythm-Regular Pacemaker site-SA node P waves-Upright and normal in morphology PR interval-normal QRS complex-normal
Sinus Dysrhythmia
Rate-60-100 Rhythm-Irregular Pacemaker site-SA node P waves-Upright and normal in morphology PR interval-normal QRS complex-normal
Sinus Arrest
Rate-Normal to slow depending on frequency and duration of arrest Rhythm-irregular Pacemaker site-SA node P waves-Upright and normal in morphology PR interval-normal QRS complex-normal
Sinus Block
Rate-normal to slow Rhythm-Regular Pacemaker site-SA node P waves-Upright and normal in morphology PR interval-normal QRS complex-normal
Sinus Pause
Rate-normal to slow Rhythm-irregular Pacemaker site-SA node P waves-Upright and normal in morphology PR interval-normal QRS complex-normal
Sick Sinus Syndrome
Rate-extremely variable (may see runs of bradycardia and tachycardia) Rhythm-irregular Pacemaker site-SA node P waves-Upright and normal in morphology PR interval-normal QRS complex-normal
Wandering atrial pacemaker
Rate-usually normal Rhythm-slightly irregular Pacemaker site-varies among the sa node, atrial tissue, and the av junction. P waves-morphology changes from beat to beat; P waves may disappear entirely PR interval-varies QRS complex-normal
Multifocal atrial tachycardia
Rate-more than 100 Rhythm-irregular Pacemaker site-ectopic sites in the atria. P waves-organized, discrete nonsinus P waves with at least three different forms. PR interval-varies QRS complex-varies (may be <.12 or >.20)
Premature Atrial Complexes
Rate-depends on underlying rhythm. Rhythm-depends on underlying rhythm; usually regular except for PAC Pacemaker site-ectopic focus in the atrium. P waves-the P wave of the PAC differs from the P wave of the underlying rhythm. It occurs earlier than the n
Paroxysmal Supraventricular Tachycardia (PSVT)
Rate-150-250 per min Rhythm-characteristically regular, except at onset and termination Pacemaker site-the atria, outside the SA node. P waves-the atrial p waves vary slightly from sinus p waves. The p wave is often buried in the preceding t wave and some
Supraventricular Tachycardia (SVT)
Rate-150-250 Rhythm-characteristically regular except at onset and termination. Pacemaker site-in the atria, usually outside the SA node. P waves-p wave may be impossible to see, especially if the rate is rapid. PR interval-usually normal can vary QRS com
Atrial Flutter
Rate-Atrial rate is 250-350 per min. Ventricular rate varies. Rhythm-atrial rhythm is regular; ventricular rhythm is usually regular, but can be irregular if the block is variable. Pacemaker site-sites in the atria outside the SA node. P waves-flutter (F)
Atrial Fibrillation
Rate-atrial rate is between 350-750 (cannot be counted); ventricular rate varies Rhythm-irregularly irregular Pacemaker site-numerous ectopic foci in the atria P waves-none discernible. Fibrillation (F) waves are present, indicating chaotic atrial activit
First degree AV block
Rate-depends on underlying rhythm Rhythm-usually regular; can be slightly irregular Pacemaker site-SA node or atria P waves-normal PR interval-greater than .20 sec QRS complex-usually less than .12 sec; may be bizarre in shape if conductive system disease
Type I Second-Degree AV Block (Wenckebach)
Rate-atrial rate is unaffected; the ventricular rate may be normal or slowed. Rhythm-atrial rhythm is typically regular; ventricular rhythm is irregular because of the nonconducted beat Pacemaker site-SA node or atria P waves-normal; some p waves are not
Type II 2nd Degree AV Block
Rate-atrial rate is unaffected; ventricular rate is usually bradycardic. Rhythm-regular or irregular depending on whether the conduction ratio is constant or varied. Pacemaker site-SA node or atria P waves-normal; some p waves are not followed by QRS comp
3rd Degree AV Block
Rate-atrial rate is unaffected. Ventricular rate is 40-60 if the escape pacemaker is junctional, less than 40 if the pacemaker is lower in the ventricles Rhythm-both atrial and ventricular rhythms are usually irregular Pacemaker site-SA node and AV juncti