Background: Pregnancy is associated with both new-onset and exacerbation of pre-existing arrhythmias, particularly supraventricular tachycardia, with increased maternal and fetal risks and with added concerns on the safety of the available drug therapy and catheter ablation techniques. These are often withheld, with worse outcomes, and lead to challenging decisions in the approach to pregnant women with refractory supraventricular arrhythmias.Case presentation: We present a case of a 28-year-old 37-weeks pregnant woman with symptomatic, almost incessant, atrial tachycardia causing tachycardia-induced cardiomyopathy, refractory to medical therapy, that evolved in acute cardiac failure and needed emergency cesarian delivery. The patient was afterward submitted to catheter ablation therapy, with an electrical isolation of the ectopic foci on the lower left pulmonary vein with radiofrequency and total suppression of the arrhythmia. The patient and infant were discharged clinically well and during follow-up the patient was asymptomatic, without recurrence of tachycardia and with complete recovery of left ventricle function. Conclusions This case highlights the challenges in the treatment of this special population with a stepwise medical approach that proved ineffective and clinical deterioration requiring termination of pregnancy and catheter ablation in the postpartum period, with a successful maternal and fetal outcome.