Back to basics: what is this rhythm? What are your options for treating this patient?

Written by Bobby Nicholson MD, with edits by Meyers, Smith, GrauerA woman in her early 40s presented to the emergency department for evaluation of palpitations. She reported that she has been experiencing this since she was diagnosed with COVID a little over 1 week ago. She reported a prior history of SVT and has previously performed vagal maneuvers at home with symptom resolution. She reports that she is now unable to vagal out of her palpitations and is having shortness of breath and dull chest pain. Her initial EKG is below.We see a regular tachycardia with a narrow QRS complex and no evidence of OMI or subendocardial ischemia. The differential of a regular narrow QRS tachycardia is sinus tachycardia, SVT, and atrial flutter with regular conduction. There are no P waves preceding the QRS complexes, and no clear flutter waves. SVT is by far the most likely rhythm in this case. There are retrograde P waves seen immediately after the QRS complex in most leads. They are inverted in lead II, for example.She was treated with 6mg adenosine rapid IV push. The following EKG was obtained after administration of adenosine.Now the patient is in sinus tachycardia. Unfortunately, shortly after this EKG was obtained, the patient returned to SVT. Same as initial ECG.Smith:should we give adenosine again?Smith:No!  Adenosine worked.  It converted the rhythm.  But adenosine only lasts for seconds, and if the dysrhythmia recurs, then the adenosine is gone.We...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs