Differential Diagnosis
- Atrial fibrillation
- Atrial flutter
- First-degree AVB
- Second-degree AVB
- Baseline artifact
Diagnosis
This ECG shows a baseline artifact.
The ability to interpret an ECG is often dependent on the quality of the tracing. This ECG reveals a regular rhythm, so atrial fibrillation, characterized by an irregularly irregular rhythm, is not occurring.
Interestingly, atrial flutter can sometimes be tricky, as it is a regular rhythm often with a rate of 150 beats per minute, but the rate can be slower if there is a block; however, this can be a silver lining as it is then easier to see the “flutter waves,” best seen in lead V1. This is not occurring here.
AV block type 1 would be difficult to discern with this ECG, as there are no p waves seen; so, we cannot determine if the PR interval is >200 ms. We do, however, know that AV block type 2 is not occurring as there are no dropped beats.
Learnings/What to Look for
- The first two things to look for are rate and rhythm; if p waves are not able to be discerned, there should be consideration for atrial fibrillation, a junctional rhythm, a ventricular rhythm, or artifact
- Baseline artifact may occur from a patient who is moving, as well as a patient with a tremor (such as in Parkinson’s disease), spinal stimulator, or if the patient is not able to remain still (for example, because of respiratory distress)
Pearls for Urgent Care Management and Considerations for Transfer
- Do not be nice! Ask for the ECG to be repeated if you do not have reliable data on which to base your decision
- With a “wavy” baseline, first look for p waves and for the rate and rhythm. Atrial fibrillation is an irregularly irregular rhythm
- Correlate ECG findings with the patient’s clinical condition