Inappropriate sinus tachycardia in pregnancy: a benign phenomena?

The syndrome of inappropriate sinus tachycardia (IST) is a well-described and generally benign condition outside pregnancy. There is, however, little information in the literature about IST during pregnancy and nothing about the likely mechanism in such cases. Equally there is a paucity of information about the effects on maternal and fetal well-being in patients who develop IST during pregnancy. Here, we describe the case of a woman who developed IST for the first time during pregnancy. We have first given a brief clinical summary of events and then follow this with the patient's personal account which she has written herself specifically for this case report. We believe that this case highlights some of the important issues associated with the condition when it occurs during pregnancy. We hope that the publication of this case report will increase the awareness of IST during pregnancy. This is important as we believe that the correct diagnosis and understanding of the condition and its consequences will allow clinicians to manage women afflicted by the condition empathetically and appropriately. 2017 BMJ Publishing Group Ltd.