A 35-year-old woman presents to the emergency department with palpitations for 2 hours. She states that she has intermittently had palpitations for years, but always lasting for minutes only. These palpitations are associated with mild dizziness and shortness of breath. No chest pain occurs.
Her temperature is 37.0° F, blood pressure is 90/50 mmHg, heart rate is 190 bpm and her respiratory rate is 16. No jugular venous distension is present, she is tachycardic and regular on cardiac exam without any murmurs. Her lungs are clear to auscultation. The rest of her exam is normal. Her ECG is below.
What are the findings of this ECG tracing?