CASE REPORT Direct current cardioversion during pregnancy should be performed with facilities available for fetal monitoring and emergency caesarean section Eleanor J. Barnes a,b, * , Friedericka Eben c , David Patterson c Case report Direct current cardioversion is reported as being a safe procedure during pregnancy 1,2 . However, the importance of carrying out fetal monitoring with an obstetrician at hand is illustrated by a woman treated in the third trimester of pregnancy, where direct current cardioversion resulted in an emergency caesarean section. A 24 year old woman attended the casualty department complaining of palpitations and heavy central chest pain that had begun 1 hour earlier. She was 28 weeks pregnant. At nine months of age she had received a Mustard operation for transposition of the great arteries (after intra-atrial repair, systemic venous blood is routed to the left ventricle and pulmonary artery. Pulmonary venous blood reaches the systemic circulation via the right vent- ricle). During childhood she had recurrent episodes of supraventricular tachycardia, which had responded to carotid sinus massage. A pacemaker was inserted at 13 years of age to treat nocturnal bradycardia. At 22 years of age, she delivered her first child spontaneously at term without complications. There had been no problems previously during her current pregnancy. A fetal cardiac ultrasound scan at 25 weeks of gestation was normal. She was not taking any medication. On examination she was centrally cyanosed. Her pulse rate was 200 beats per minute and her blood pressure was 100/50 mmHg. Her heart sounds were normal and she had no signs of cardiac failure. A 12-lead electrocardiogram confirmed a supraventricular tachycardia, with lateral ST depression and T wave inversion. A cardiogram showed a fetal heart rate of 160 beats per minute, with no abnormal features. Carotid sinus massage and the Valsalva manoeuvre failed to terminate the tachycardia. She was treated with intravenous adenosine 3, 6 and 12 mg. With a dose of 12 mg adenosine, she converted to sinus rhythm and the blood pressure remained at 100/50 mmHg. Within min- utes, the supraventricular tachycardia returned and she was treated with verapamil 5 mg intravenously. Again, sinus rhythm was restored. The fetal heart rate was monitored throughout. The woman was admitted to the ward for observation. Two hours later, the supraventricular tachycardia re- curred, the heart rate being 185 beats per minute. Adenosine and verapamil failed to terminate the tachycardia. Her blood pressure was 110/60 mmHg. The woman was turned to the left lateral position to maximise her venous return. She was treated with 240 mg sotalol and a loading dose of 500 Ag of digoxin orally in an attempt to control the ventricular rate. Thirty minutes later, she developed increasing chest pain. Her blood pressure decreased to 60/40 mmHg, with a per- sisting heart rate of 200 beats per minute. She was transferred urgently to the operating theatre for direct current cardio- version under general anaesthesia. The fetal heart rate was monitored constantly. A synchronised shock of 50 J was delivered and the maternal heart rhythm was converted immediately to sinus rhythm, at a rate of 90 beats per minute. Her blood pressure increased to 110/80 mmHg. Before the cardioversion, the fetal heart rate was 130 beats per minute. Immediately after cardioversion, the fetal heart rate decreased to 80 beats per minute. The bradycar- dia was sustained over the following 5 minutes, and the fetal heart rate then decreased further. The heart also was noted to be dyskinetic. Emergency caesarean section was performed. At caesarean section the uterus was tightly contracted. A female infant was delivered. The baby gave a weak cry at delivery but had irregular, weak respiration. She was intubated and ventilated with 1 PPV for approximately 1 minute. She was bradycardic at delivery but after 1 minute the heart rate was 100 bpm. Apgar scores were 7 and at 5 minutes were 10. She was transferred to the neonatal unit. Following caesarean section the mother remained in sinus rhythm, and her infant made a full recovery. BJOG: an International Journal of Obstetrics and Gynaecology December 2002, Vol. 109, pp. 1406–1407 D RCOG 2002 BJOG: an International Journal of Obstetrics and Gynaecology PII:S1470-0328(02)02613-7 www.bjog-elsevier.com a Royal Free Hospital, London, UK b Nuffield Department of Medicine, Oxford, UK c Whittington Hospital, London, UK * Correspondence: Dr E. J. Barnes, 169C Woodstock Road, Oxford, OX2 7NA, UK.