Practice EKG Strips 425

Identify the following rhythms.

1.

a. Idioventricular rhythm
b. Complete heart block
c. Junctional rhythm
d. Sinus bradycardia with first degree block

2.

a. Sinus rhythm with trigeminal PVCs
b. Sinus rhythm with unifocal PVCs
c. Sinus rhythm with multifocal PVCs
d. Sinus rhythm with a triplet of PVCs

3.

a. Second degree heart block type II
b. Sinus rhythm with sinus arrest
c. NSR with a dropped PAC
d. Complete heart block

4.

a. Sinus tachycardia
b. Atrial fibrillation
c. Multifocal atrial tachycardia
d. Atrial tachycardia

5.

a. Sinus tachycardia
b. Atrial fibrillation
c. Supraventricular tachycardia
d. Atrial tachycardia



Answers
1.  b. Complete heart block. The ventricular rate is 42. The atrial rate is around 115. The rhythm looks regular. The P waves and the QRS complexes are not associated.  The QRS complexes in this strip are narrow.   This indicates that the block was higher in the ventricle and located near the AV junction.  The rate of 42 is about what you would expect for an underlying junctional escape mechanism.

2. b. Sinus rhythm with unifocal PVCs. The unifocal PVCs occur every 5th beat

3. a. Second degree heart block type II. The PR interval on the conducted beats is the same, .16 seconds. Two nonconducted beats follow the 1st complex. Answer A is incorrect because the non conducted P waves are present- this shows a functioning SA node. Answer C is not correct because the dropped beats do not arrive early in the cardiac cycle. Answer D is not correct because of the pairing of the P waves and the QRS complexes on the conducted beats- in CHB this pairing would be absent.

4. c. Multifocal atrial tachycardia.  The rhythm is irregular with a rate of 110/min.  Upright P waves are present before each QRS complex but the morphology of the P waves varies.  The QRS complexes are narrow.  PR: varies slightly, QRS: .08 sec, QT: .28 sec.

5. b. Atrial fibrillation.  The rhythm is irregularly, irregular with a rate of 120/min.  No P waves are seen.  The QRS complexes are narrow.  No ectopic beats are seen.  PR: --, QRS: .08 sec, QT: . 36 sec.