Tachycardia in pregnancy: when to worry?

Tachycardia in pregnancy is common, and distinguishing between physiological and pathological causes can be a challenge. Understanding the cardiovascular changes that take place in pregnancy can help to direct investigations. The finding of a persistent tachycardia, regardless of symptoms, should always prompt clinical review and consideration of investigations (such as blood tests, electrocardiography and echocardiography), where indicated. Treatment of tachyarrhythmias in pregnancy differs very little from a non-pregnant adult, and unstable arrhythmias should follow Resuscitation Council UK guidelines. Pregnant women with pathological arrhythmias need to be cared for under a multidisciplinary team, including obstetricians, obstetric anaesthetists, specialist midwives, cardiologists and obstetric physicians.