A Pregnant Patient with Elevated Heart Rate

Inappropriate sinus tachycardia (IST) is a largely benign condition, occurring in approximately 1% of the population.1 According to the Heart Rhythm Society, the syndrome of inappropriate sinus tachycardia is a diagnosis of exclusion, specifically with sinus heart rate (HR) >100 beats per min (bpm) at rest with a mean HR >90 bpm over 24 hours, associated with activity limiting symptoms including palpitations, dizziness, syncope or weakness.2 Herein, we present the diagnosis, pathophysiology, and management of this rare entity.