386) A 54 year old man presents to the emergency room with dizziness and intermittent palpitations for the past 12 hours. He denies any syncopal episodes or headache or seizures. He has no significant cardiac history. He was seen in the outpatient clinic one week ago for pneumonia and was started on Moxifloxacin. His other medical problems include hypertension for which he is on enalapril and Gastro-esophageal reflux disease for which he takes esomoprazole. Physical examination reveals regular heart sounds and no murmurs. Complete Blood Count and Serum electrolytes are within normal limits. An electrocardiogram is obtained and is shown below:
Which of the following is the most appropriate action at this time?
A) Intravenous Magnesium sulfate
B) Discontinue Moxifloxacin
C) Discontinue Esomoprazole
D) Transvenous Pacing
E) Intravenous Isoproterenol
Filed under: Uncategorized, USMLE Test Prep | Tagged: Archer cardiology, USMLE STEP 3 CARDIOLOGY |
A
A) Intravenous Mg sulfate
Prolong QT interval???
Yes, just prolonged QT interval as you can see from EKG. No active torsades at this time. So what would be the 1st step?
B) Discontinue Moxifloxacin and admition with close monitoring
B)
A
Why A? what is the etiology? Should not the offending agent be stopped first. There is no active torsades anyway except for prolonged QT on EKG
then B foll by A?
Correct! after completing B, magnesium sulfate can be given to prevent recurrences because it appears like the patient did have arrythmias given the history of palpitations. However, currently EKG shows QT prolongation without arrhythmia
B ….damn sure…..
thanks for explanation!!!!!