a. Atrial fibrillation
b. Atrial flutter
c. Atrial tachycardia
d. Atrial paced
a. NSR with a triplet of PVCs
b. Sinus arrhythmia with a triplet of PVCs
c. First degree block with a triplet of PVCs
d. Accelerated junctional rhythm with a triplet of PVCs
a. Sinus arrhythmia
b. Normal sinus rhythm
c. Sinus rhythm with a pause
d. Sinus tachycardia
a. Normal sinus rhythm with sinus arrest
b. Sinus bradycardia with a pause
c. Sinus arrhythmia, sinus bradycardia
d. Complete heart block
a. Atrial flutter changing to VT
b. Sinus rhythm changing to VT
c. Sinus tachycardia changing to VT
d. Accelerated junctional changing to VT
1. b. Atrial flutter. The rhythm is irregular with a rate of 90 bpm. No P waves are seen just some inverted or retrograde flutter waves. Atrial flutter is thought to be due to a re-entry type mechanism. The conduction to the ventricles varies 1:1 to 3:1. The flutter rate is about 300 bpm. The QRS complexes are narrow. No ectopic beats are seen.
2. d. Accelerated junctional rhythm with a triplet of PVCs. The overall rhythm is regular. The underlying heart rate is around 68 bpm. Retrograde P waves are seen before each QRS complex. Must be something from around the AV junction. The QRS complexes are narrow- indicating normal conduction through the ventricular system. A three beat run of VT or a triplet of PVCs is seen at the end of the strip.
3. a. Sinus arrhythmia. The rhythm is irregular. The R - R interval between the 1st and 2nd complexes is 0.56 sec and the R - R interval between the 5th and 6th complexes is 0.92 sec. The P waves are upright but they tend to flatten out as you progress through the strip. The PR interval appears unchanged though. The QRS complexes are narrow, .08 sec, No ectopy is seen.
4. b. Sinus bradycardia with a pause. The underlying rate is 53 bpm. The rhythm is irregular due to the pause. Normal conduction resumes after the pause so this is more characteristic of a pause rather than a period of arrest. The P waves are upright and paired with a QRS complex. The QRS complexes are narrow. No ectopic beats are seen
5. b. Sinus rhythm changing to VT. Some small sinus P waves can be seen on the first two complexes. The PR interval is 0.20 sec, so borderline first degree block. The underlying rate (based on the R - R interval of the two sinus beats) is 88 bpm. The rhythm changes to a polymorphic looking VT.