LAUSR

A 41-year-old woman was assessed for recurrent intermittent irregular palpitations, associated with dizziness and shortness of breath. She had a negative electrophysiology study 12 years earlier, for similar symptoms. In addition, β-blockers, calcium-channel blockers (Verapamil), and flecainide did not result in significant improvement of her arrhythmia. A recent echocardiogram disclosed a structurally normal heart. Following the electrocardiogram recorded during one of her latest emergency department visits (Figure 1), oral anticoagulation was started and a referral for electrophysiology opinion was made. What is the arrhythmia displayed in Figure 1, and what is the explanation of the irregularity in the rhythm? Please turn the page to read the diagnosis. Andrei D. Margulescu, MD, PhD Dewi E. Thomas, MD