Some pearls from our ECG report today:

• DDx for ST elevations on ECG:
  • Pericarditis (diffuse)
  • Ischemic heart disease (MI, Prinzmetal angina, ventricular aneurysm) –> tends to present in one vascular territory
  • LBBB
  • Early report variant (AKA J point elevation)
• A flutter at its fastest (2:1 block) would have a rate of 150 bpm (meaning atrial rate is 300 bpm).  So if you  have a regular, narrow complex tachycardia that is going faster than 150 bpm, then start thinking AVRT or AVNRT.
• A rough estimate of maximum SA node rate possible in a patient is 220 – age.
• If you see a slow a fib with QRS waves at regular intervals, think of dig toxicity!  Because dig increases atrial and ventricular ectopy, the atria start to fibrillate. At the same time, the AV node is being blocked.  So what you are actually seeing on ECG is fibrillating atrium with complete heart block causing a slow junctional escape rhythm.  Keep in mind though that the most common abnormality on ECG for dig toxicity is PVCs.