Practice EKG Rhythm Strips 152

Identify the following rhythms.

1.

2.

3.

4.

5.

Answers

1.

1st degree block with multifocal couplet

 The rhythm is irregular due to the PVCs.   The rate is  80/min.  The P waves precede the QRS complex but the PR interval is prolonged and measures .32 sec.   A multifocal couplet is present.  PR:  .32 sec,  QRS:  .08 sec,  QT:  .40 sec.



2.

3rd degree heart block

The atrial rate is around 80/min while the ventricular rate is around  33.  The P waves are dissociated from the QRS complexes.  On the V1 lead it is easy to identify the P waves that fall within the QRS complex.  No ectopic beats are present.  PR:  ---,  QRS:  .16 sec,  QT:  .60 sec.


3.

Blocked premature atrial beats

The rhythm is irregular due to the pauses.   The rate is 50/min.  The P waves are upright and precede the QRS complexes.   A dropped PAC follows the 4th and 5th complexes. They are dropped PACs because they come early in the cardiac cycle.  These are atrial ectopic beats that are not conducted and that do not produce any ventricular depolarization.


4.

Normal sinus rhythm with trigeminal PVCs

 The rhythm is irregular due to the PVCs.  The rate is 80/min.   The P waves are upright and are associated with the QRS complexes. Unifocal PVCs are seen every third beat.  PR:  .16 sec,  QRS: .08 sec,  QT:  .44 sec.


5.

Monomorphic ventricular tachycardia changing to ventricular fibrillation

The rhythm is irregular because of the transition from ventricular tachycardia to ventricular fibrillation.   The monomorphic ventricular tachycardia has a rate of 187/min.   This degenerates into a coarse ventricular fibrillation.