Case

A woman in her early 30s self-presents to her local ED at 03:00 hours and is brought from triage to resus due to a tachycardia of 220 beats per minute (bpm). She is 15 weeks into her first (twin) pregnancy, has no medical history and takes no regular medication. She reports a 2-day history of intermittent ‘palpitations’ which are now constant. She describes feeling presyncopal on standing with some mild chest discomfort and shortness of breath. Examination is unremarkable other than a tachycardia. Other vital signs are BP 93/67 mmHg, RR 24 breaths per minute, SpO2 99% on room air and temperature 36.3°C. An ECG (figure 1) is performed and intravenous access is obtained.

Question 1: What does this ECG show and how does her pregnancy affect your initial management?

Answer 1: A regular, narrow complex tachycardia. In V2, there appear to be p waves prior to each QRS but they are not clear on other leads. Combining the history of intermittent palpitations, the extreme tachycardia and the ECG findings, this patient was managed following supraventricular tachycardia (SVT) guidelines as the whole clinical picture did not fit a sinus …