Anesthesia for Cesarean Delivery in a Patient with Congenitally Corrected Transposition of the Great Arteries: A Case Report

ABSTRACT

Congenitally corrected transposition of the great arteries (CCTGA) is a rare form of congenital heart disease often associated with other cardiac defects. The adaptations and physiologic changes in pregnancy can present maternal challenges and complications; multidisciplinary care allows for the safest management of pregnancy and delivery in these patients. We present a case of the anesthetic management of cesarean delivery in a woman with CCTGA with her pregnancy complicated by recurrent volume overload, pulmonary hypertension, and dysrhythmias.

INTRODUCTION

Congenitally corrected transposition of the great arteries (CCTGA) is a congenital heart disease typified by atrioventricular as well as ventricular-arterial discordance. Patients may present in adulthood as they typically do not have cyanosis unless there are other associated cardiac defects. The incidence of CCTGA is 0.03 per 1000 live births.[1] Complications typically arise from the development of systemic tricuspid valve regurgitation and systemic right ventricle failure. The pregnancy-associated increase in blood volume, cardiac output, and stress of labor and delivery can result in complications and requires specialized cardiology, obstetric, anesthesia, and postpartum care. There is a paucity of literature on anesthetic management in this population. We report the perioperative planning for cesarean delivery in a patient with CCTGA. The patient provided written HIPAA authorization for publication.

CASE HISTORY

Our patient was a 31-year-old G4P0030 with complex congenital heart disease including situs inversus totalis, ventricular inversion [I, D, D-MGV] double outlet right ventricle (RV) with associated subvalvular, valvular, and right pulmonary artery (PA) stenosis, large inlet ventricular septal defect (VSD) and secundum atrial septal defect (ASD), chronic cyanosis and had two spontaneous abortions in that setting. She underwent an ASD and VSD patch repair and pulmonary outflow tract reconstruction with left ventricle (LV) to PA conduit (homograft) placement at age 26 complicated by postoperative complete heart block requiring pacemaker placement in her subpulmonary LV. Figure 1 demonstrates the patient’s cardiac anatomy. She was medically optimized and counseled regarding the high maternal cardiovascular and fetal risks of pregnancy in the setting of severe systemic tricuspid regurgitation and systemic RV dysfunction and became pregnant after transitioning to a non-teratogenic heart failure regimen.

Figure 1.

Anatomy (a) Normal anatomy and CC-TGA (b) Our patient’s anatomy including situs inversus totalis, congenitally corrected transposition (ventricular inversion), severe valvular PS, ASD, VSD, s/p ASD, and VSD patch repair and pulmonary outflow tract reconstruction with LV to PA conduit. With the relief of pulmonary stenosis postoperatively the septum shifted to the LV, TV leaflets splayed, and TR increased resulting in heart failure

She presented at 27 weeks with volume overload and supraventricular tachycardia requiring diuresis and medication titration and was readmitted at 31 weeks with worsening heart failure. On admission, her physical exam was notable for jugular venous distension, prominent P2, S3, and S4 heart sounds, and orthopnea. Her home medications included metoprolol, digoxin, and torsemide. Her transthoracic echocardiogram (TTE) demonstrated a dilated, hypertrophied systemic morphologic-RV with systolic impairment with an ejection fraction of 47%, a sub-pulmonary morphologic-LV with moderate systolic dysfunction, severe systemic tricuspid regurgitation, elevated LV pressure of 59 mmHg, and no LV-PA conduit stenosis. Figure 2 demonstrates systemic RV systolic dysfunction with severe tricuspid regurgitation. She received aggressive diuresis with IV bumetanide and metolazone. Daily nonstress tests for the fetus were reassuring, she received betamethasone for fetal lung maturation, and fetal presentation was transverse. Given the patient’s cardiac status and risk of worsened volume overload with ongoing pregnancy, a multi-disciplinary decision was made to proceed with cesarean delivery with adult congenital cardiology, maternal–fetal medicine, and obstetric and cardiac anesthesia teams.

Figure 2.

TTE Images (a) Short axis view of hypertrophied systemic RV and sub-pulmonic LV (b) Subcostal view notable for hypertrophied systemic RV (c) Apical four-chamber view demonstrating severe systemic TR

A peripherally inserted central catheter line was placed in anticipation of delivery that was planned in a cardiac surgical operating room. Her pacemaker was DDD-R with 100% ventricular pacing which was left unchanged for the delivery. The patient had a left radial arterial line placed; bumetanide infusion was continued at 0.25 mg/hour and milrinone was initiated at 0.3 μg/kg/min. She was administered aspiration prophylaxis and received a combined spinal epidural (CSE) using a 17-g Weiss needle and a 25 g Whitacre spinal needle at the L3–L4 level. In total, 0.5 mL of 0.75% hyperbaric bupivacaine with morphine (150 μg) and fentanyl (15 μg) was injected intrathecally. A wire-reinforced, single-orifice epidural catheter was threaded 5 cm into the epidural space and a test dose was administered with 3 mL of 1.5% lidocaine with 15 μg of epinephrine that was negative for intrathecal or intravascular placement. She was positioned supine with right uterine displacement given her situs inversus and defibrillator pads were placed. The epidural was dosed with 2% lidocaine with 5 μg/mL epinephrine in 3–5 mL increments until she developed an anesthetic level to T4. She briefly required low-dose norepinephrine following the initiation of neuraxial anesthesia. A magnesium infusion was started at 1 g/hour and potassium supplementation was ongoing due to frequent ectopy.

At the point of uterine incision, epinephrine was started at 1 mcg/min for inotropic support. The neonate was delivered with Apgar scores of 8 and 9 and required continuous positive airway pressure. Following delivery, an additional bolus of 2.5 mg bumetanide IV and 10 U of oxytocin intramuscular was administered. Nitroglycerin infusion was initiated for preload and afterload reduction. The uterine tone was excellent and the estimated blood loss was 500 mL. She received 300 mL lactated ringer’s, ketorolac, and ondansetron. The epidural catheter was removed at the end of the case. Figure 3 shows the hemodynamic profile throughout the course of the cesarean delivery.

Figure 3.

Intraoperative record screenshot. Intraoperative hemodynamics notable for initial narrow pulse pressure with widening throughout the course of the procedure secondary to vasodilator therapy as well as an abrupt rise in central venous pressure following delivery

Postoperatively, she was managed in the intensive care unit with IV diuresis and inotropic support that was weaned off over two days. She was medically optimized on lisinopril, metoprolol, digoxin, torsemide, and fluid and salt restriction. She was transferred to the floor on postpartum day 4 and discharged on postpartum day 8. The patient was briefly hospitalized twice outside of the USA for fluid overload due to lack of access to home torsemide and one-year postpartum she is doing well without evidence of heart failure.

DISCUSSION

Patients with CCTGA generally tolerate the physiologic changes of pregnancy, labor, and delivery well based on case series that demonstrate live births in 70–95% and maternal cardiovascular complications in 5–25% of cases, however, the numbers are low.[2,3] Isolated cases of CCTGA are rare and the majority of patients have additional lesions including VSD, pulmonary stenosis, Ebstein’s anomaly, aortic coarctation, tricuspid atresia, and dextrocardia.[4] Patients with co-existing cardiac defects, particularly those with congestive heart failure and/or arrhythmias, have an increased likelihood of complications during the peripartum period. Interdisciplinary planning is imperative to optimize patients with underlying cardiac disease and specialist anesthesia care should be available.[5]

Risk factors for cardiovascular events in pregnancy include poor functional class, systemic ventricular dysfunction, high-risk valvular disease, prior arrhythmias, high-risk aortopathy, pulmonary hypertension, coronary artery disease, and cyanotic heart disease.[6] The modified World Health Organization classification stratifies the risk of complications in pregnant patients with heart disease. Our patient was considered Class III, placing her at a significantly increased risk of maternal morbidity and/or mortality.[7]

Intraoperative monitoring requirements for cesarean delivery in these patients vary depending on the associated comorbidities. Given our patient’s history, we proceeded with invasive arterial blood pressure and central venous pressure monitoring. We avoided PA catheterization given her complex anatomy and the potential risk for dysrhythmias during placement. Intraoperative TTE equipment was available to guide resuscitation and inotropic support and is a valuable monitor in these cases.[8] The Extracorporeal Membrane Oxygenation team was on standby for peripartum mechanical circulatory support with venoarterial configuration. Consideration was also given to an RV peripheral ventricular assist device; however, there was concern that this would be challenging given her anatomy and trabeculations of her RV.

Neuraxial anesthesia is preferred over general for cesarean delivery as it carries lower maternal risk, limits fetal medication exposure, and avoids intubation and positive pressure ventilation. CSE anesthesia provides the benefit of intrathecal medication administration with the ability to titrate and supplement the block with an epidural catheter. The published literature on the anesthetic management of these patients is limited given the condition’s rarity; prior reports describe epidural anesthesia for cesarean delivery.[9] CSE anesthesia avoids the hemodynamic swings that can occur with a single-shot spinal while increasing the reliability compared with epidural blockade.[10] We used a low-dose spinal and slowly dosed the epidural under continuous monitoring with inotropic support and vasopressors.

Hemodynamic goals for patients with underlying systemic ventricular dysfunction include maintaining an adequate heart rate, avoiding dysrhythmias, and reducing afterload. Intraoperatively, we avoided factors that increase afterload and pulmonary hypertension including pain, hypercapnia, hypoxemia, and acidosis. Immediately following delivery, the autotransfusion and rise in cardiac output and systemic vascular resistance presented a challenge to the sub-pulmonary morphologic LV and the systemic RV. Our goals were to maintain preload and afterload reduction, adequate inotropy, judicious fluid management, and to avoid electrolyte abnormalities with a great outcome.

Glossary of terms

CCTGA = Congenitally corrected transposition of the great arteries; RV = Right ventricle; PA = Pulmonary artery; VSD = Ventricular septal defect; ASD = Atrial septal defect; LV = Left ventricle; IV = Intravenous; TTE = Transthoracic echocardiography; CSE = Combined spinal epidural.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.