Question

64yo male, with a history of HTN, DMII, and hyperlipidemia, is brought in by EMS to the ED with a 2 hour history of lightheadedness and palpitations.  He states both these symptoms seem to fluctuate and nothing seems to make them better or worse when they occur.  He has never had anything like this before.  He denies syncope, chest pain, dyspnea, nausea, vomiting, diaphoresis, or vision changes.

Medications

Lisinopril 10mg

Metformin 1000mg

Simvastatin 20mg

Physical Exam

General – NAD, A&Ox3

HEENT – no diaphoresis, no gaze deviation, no facial palsies

CV – irregular, no M/G/R

Pulm – CTA bilaterally

MSK – 5/5 strength throughout

Neuro – CN II-XII grossly intact, MAE

While getting set up for a formal 12 lead EKG, the paramedic hands you the rhythm strips from transport:

What is the most likely diagnosis?