Management of parturients after corrected transposition of great arteries-report of two cases.
Abstract Number: 216
Abstract Type: Case Report/Case Series
Introduction: Transposition of great arteries(TGA) is relatively common cyanotic congenital cardiac defect. In the most common form the aorta is connected to the right ventricle and the pulmonary artery is connected to the left ventricle resulting in two parallel circulations. Many women are now presenting during pregnancy having undergone correction of the TGA in infancy.
Case 1: A 20 year old (G1P0) woman with a history of Rashkind septoplasty followed by Senning procedure for TGA presented to the obstetric anaesthetic clinic at 35/40. On examination her heart rate was 50-70 beats per minute with episodes of symptomatic nodal bradycardia. Her echocardiogram reported moderate right ventricular function and tricuspid regurgitation. Her IVC baffle was widely patent while her SVC baffle showed turbulence indicating narrowing. After multidisciplinary consultation it was felt there would be a limit in her ability to increase cardiac output during the delivery due to her reduced ventricular reserve and nodal bradycardia. A plan for elective Caesarean section (CS) was made at 37/40. A temporary atrial pacing wire was placed prior to surgery with subsequent improvement in her blood pressure. An uneventful CS was performed under continuous spinal epidural (CSE) anaesthesia. Four months later she presented to the cardiologists with progressive decrease in exercise tolerance, lethargy and palpitations. While her cardiac function remained stable, significant nodal bradycardias were noted in the 24hr ECG recording. A permanent pacemaker was inserted and thereafter, her symptoms improved. Two years later she presented at 35/40 gestation in labour and underwent an uneventful emergency CS under CSE.
Case 2: A 30 yr old (G1P0) with a history of Mustard operation for TGA presented to our anaesthetic clinic at 26 weeks gestation. She had a history spinal surgery with internal fixation performed twice for scoliosis. She also had a history of multiple ischaemic strokes. On examination she was 1.52cm tall, with marked residual scoliosis and severe restrictive lung function with FEV1 of 56% of predicted value. Echocardiograms at 12 and 24 weeks gestation showed dilatation of her systemic right ventricle with moderately impaired function. She was on deltaparin 5000 I.U and aspirin 75mg for her recurrent strokes. Examination of her back revealed a scar extending from high thoracic to L3/4 with palpable interspace at L4/5. At 34/40 she presented to the cardiologist with increasing breathlessness and was commenced on diuretic with no significant symptomatic improvement. After multidisciplinary consultation at 35+2/40 she was delivered by elective CS under continuous spinal anaesthesia.
Discussion: Late complications are common after corrected TGA. Both our patients presented with recognised complications and were successfully managed by careful planning and conduct of our multidisciplinary team.
1.Yarrow S,Russell R,IJOA 2000;9:179-85.