Background: Pregnancy can precipitate cardiac arrhythmias not previously present in seemingly well individuals. Atrial and ventricular premature beats are frequently present during pregnancy and are usually benign. Supraventricular tachycardia and malignant ventricular tachyarrhythmias occur less frequently. Maternal and fetal arrhythmias occurring during pregnancy may jeopardize the life of the mother and the fetus.
Case Report: A 32-year-old pregnant women at 26 weeks gestation presented to the emergency department with palpitation. She had mild chest discomfort after a supraventricular tachycardia (SVT) episode but did not have syncope. After monitoring and access of an IV line, vagal manoeuvres were applied but the rhythm was resistant. Then she was treated with 5 mg metoprolol IV, but the SVT persisted. Then after IV infusion of adenosine triphosphate 6 to 12 mg, the rhythm was resistant. Synchronized cardioversion with 100 joules was performed. Patients’ rhythm was normalized to a sinus rhythm. She was discharged from hospital without any adverse effects following 24-hour monitoring.
Conclusions: All pregnant patients with SVT require careful maternal and fetal monitoring during treatment, and close collaboration between the managing obstetrician and the cardiologist is essential.

Keywords: supraventricular tachycardia, Pregnancy, electrical cardioversion