Float Nurse

Second degree Type I changing to second degree type II.  This patient switched back and forth between a type I block and a type II block.  

On this page you can see the progressive prolongation of the PR interval over successive beats.  The dropped beat is not seen in lead I but you can see it clearly in leads II and aVR.  A PVC interrupts the cycle of beats.  Instead of continuing in the cycle, the cycle of beats starts over after a compensatory pause.

This patient had an intermittent type I block.  He would have periods of sinus rhythm and then have periods of 2nd degree type I block.  The grouping on the type I block was not always consistent.  It may have been 3 beats in one group and 5 beats in another group.

Identify the following rhythms. 1. 2. 3. 4. 5. Answers 1. 2nd degree heart block type I The rhythm is irregular with a rate of 60/min.   The P waves are uniform and upright.   There is some splitting of the P wave which is often seen with biatrial enlargement.   There is progressive elongation of the PR interval over successive beats.   There is a dropped P wave after the 2nd QRS complex.   The QRS complexes are narrow.   PR:  .20/.24/..26/.30 sec.   QRS:  .08 sec,  QT:  .44 sec.   Interpretation:  2nd degree heart block type I 2. Accelerated junctional changing to sinus rhythm The rhythm is slightly irregular.   The heart rate is 83/min.   The P waves are negative or possibly biphasic in complexes 1 through 5 and then are positive in the remaining complexes.   The QRS complexes are narrow.  PR:  .10 sec,  QRS: ...

Identify the following rhythms. 1. 2. 3. 4. 5. Answers 1. 2nd degree AV block type I The rhythm is irregular with a rate of 60/min.   There are upright P waves present.   There is progressive elongation of the PR interval over successive beats.   A non-conducted P wave follows the 4th complex.   No ectopic beats are present.   The QRS complex is narrow.   PR:  .28/.32/.36 sec.  QRS:  .08 sec,  QT:  .44 sec.   Interpretation:  2nd degree AV block type I 2. Atrial paced rhythm  The rhythm is regular with a rate of 75/min.   There are small upright P waves that follow the atrial pacer spike.  No ectopic beats are seen.  PR:  .28 sec.  QRS:  .08 sec,  QT:  .34 sec.   Interpretation:  Atrial paced rhythm 3. NSR with a pause followed by a junctional escape beat  The rhythm is irregular.   The...

Identify the following rhythms. 1. 2. 3. 4. 5. Answers 1. Complete heart block The rhythm is regular with a ventricular rate of 35 and an atrial rate of 90/min.   The P waves are upright and uniform but are not associated with a QRS complex.   No ectopic beats are present.   The wide QRS complex suggests a ventricular escape mechanism.    PR:  ---,  QRS:  .12 sec.  QT:  .40 sec. 2. 2nd degree AV block with a PVC The rhythm is irregular with a heart rate of 40/min.   The P waves are upright and uniform.   There are P waves associated with some of the QRS complexes but there are also some dropped complexes.  On the conducted beats, the PR interval is fixed.  A single PVC is present.   PR:  .36 sec.   QRS:  12 sec,   QT:  .56 sec, 3. 1st degree heart block ...

Identify the following rhythms. 1. 2. 3. 4. 5. Answers 1. 2nd degree heart block type II The rhythm is irregular with a ventricular rate of 20/min and an atrial rate of  75/min.   The P waves are upright but not all of them are paired with a QRS complex.  No ectopic beats are noted.  The QRS complex is wide.   PR:  .20 sec,  QRS:  .12 sec,  QT:  .64 2. 2nd degree heart block type I The rhythm is irregular with a heart rate of 50/min.   The P waves are upright and uniform.    There is a nonconducted P wave after the 2nd complex.    The PR interval progressively lengthens over successive beats.   PR:  .20/.24/.32sec,  QRS:  .08 sec,  QT:  .40 sec 3. 3rd degree heart block The rhythm is regular with a ventricular rate of 30/min and an atrial rate of 100/min.   The P waves are upright and unifor...

Identify the following rhythms. 1. 2. 3. 4. 5. Answers 1. Complete heart block The rhythm is regular with a ventricular rate of 35/min and an atrial rate of 100/min.   The P waves and the QRS complexes are not associated.   The wide QRS complexes with a slow rate is indicative of  a ventricular escape rhythm.   PR:  ---,  QRS:  .16 sec,  QT:  .40 sec. 2. NSR with a multifocal couplet The rhythm is is irregular due to the PVCs.   The heart rate is 90/min.   The P waves are upright and appear before the QRS complexes.  A multifocal couplet is present.  The rSR pattern in the V1 lead suggests a RBBB.   There is 1mm ST depression in lead II.  PR:  .16 sec,  QRS:  .12 sec,  QT:  .36 sec. 3. NSR with trigeminal PACs The rhythm is irregular with frequent PACs.   The rate is 100/min.  ...