Case Report Management of 760-g Extremely Premature Infant With Dextro-Transposition of the Great Arteries Jawad R. Khazaal, BS 1 , Heather A. Sowinski, DO 2,3 , Christopher Ratnasamy, MD 2,3 , Joseph J. Vettukattil, MD 2,3 , and Marcus P. Haw, MBBS 2,4 1 Michigan State University College of Human Medicine, Grand Rapids, MI, USA 2 Congenital Heart Center, Spectrum Health Helen DeVos Children’s Hospital, Grand Rapids, MI, USA 3 Pediatrics and Human Development, Michigan State University College of Human Medicine, Grand Rapids, MI, USA 4 Surgery, Michigan State University College of Human Medicine, Grand Rapids, MI, USA DOI: 10.1177/2150135120908777 Abstract Extremely low birth weight neonates with complex congenital heart disease have increased mortality risk. Multi-organ dysfunction, pul- monary disease, fluctuating pulmonary vascular resistance, and complex cardiovascular anatomy create a challenge for effective management. We present the case of a 760-g neonate with dextro- transposition of the great arteries, ventricular septal defect, patent ductus arteriosus, and single coronary artery with proximal intramural segment of the right coronary artery branch. We describe features of preoperative care, surgical intervention, and postoperative course that enabled this infant to survive. Introduction The arterial switch operation (ASO) carries increased mortality risk when performed in neonates <2,000 g. 1,2 In general, mortality is sig- nificantly higher in neonates <1,500 g undergoing cardiac surgery in which cardiopulmonary bypass is used. 3 Complications of prematur- ity, such as neonatal respiratory distress syndrome (NRDS), inade- quate growth, sepsis, necrotizing enterocolitis, intraventricular hemorrhage, and retinopathy of prematurity, are exacerbated by the physiology of dextro-transposition of the great arteries (d-TGA). The risk of surgical intervention in an extremely low birth weight (ELBW) neonate with d-TGA creates a challenging clinical scenario where supportive measures aimed at allowing adequate growth prior to surgical repair are essential. Case Report An infant born at 26 weeks’ gestation and 760 g arrived to the emergency department after an unexpected delivery at a veterinary clinic. Following initial tracheal intubation, the patient was transitioned to nasal intermittent positive pressure ventilation (NIPPV). Poor saturations prompted an echocardiogram, which confirmed the diagnosis of d-TGA with ventricular septal defect (VSD) and a patent ductus arteriosus. Prostaglandin treatment was initiated. A multidisciplinary team including neonatology, gastroenterology, cardiology, and congenital cardiothoracic surgery established that cor- rective surgery would be delayed until a weight of 2,000 g. The patient was started on total parenteral nutrition followed by orogastric feeds from day 11 onward. The patient developed NRDS requiring frequent adjustment of NIPPV pressures and FIO 2 in order to sustain optimum saturations (70%-80%). At four weeks, pulmonary overcirculation was noted and furose- mide was initiated. Carbon dioxide (CO 2 ) retention necessitated intu- bation at five weeks. Maintaining oxygen saturations became increasingly difficult, despite respiratory support, furosemide, and prostaglandin. The process was underscored by evidence of progres- sive lung disease on X-ray and increasingly frequent changes to respiratory support settings. At eight weeks (1,400 g), echocardiogram showed the atrial septal defect had become restrictive, which precipitated episodes of desa- turation. Balloon atrial septostomy (BAS) was performed urgently, raising saturations to >90%, which allowed discontinuation of pros- taglandin and weaning FiO 2 to 28%. Respiratory support was transi- tioned to continuous positive airway pressure at ten weeks. Desaturations warranted reinstitution of prostaglandin at 12 weeks and a second BAS at 14 weeks (2,000 g), which allowed further delay of ASO. At 2,000 g, decision for repeat BAS rather than ASO was reached because of significant NRDS on X-ray and clinical instability, suggesting the patient may not tolerate surgical correction. 4 Balloon atrial septostomy stabilized the patient’s clinical condition and per- mitted additional time for preoperative growth. The patient remained intubated throughout the remainder of preoperative management. At 17 weeks (2,450 g), ASO was performed. External appearance suggested that two coronary arteries were arising from sinus 1 and sinus 2. On transection of the aorta, a single coronary orifice in facing sinus 1 was seen. The left coronary artery branch was widely patent. The course of the right coronary artery branch included a short oblique proximal intramural segment, which showed no signs of obstruction, allowing passage of a 2 mm probe (Figure 1A). Unroofing was not performed in order to avoid injury. The facing commissure of the aortic valve was released, and a large button was harvested from the ascending aorta. The top of the button was then sewn edge-to-edge to the superior cut edge of the transected proximal pulmonary artery (PA; neoaorta) without inversion or rotation to prevent any distortion of the coronary ostium (Figure 1B). Coronary transfer and neoaortic recon- struction were completed using an extending patch of autologous pericardium sutured around an opening anteriorly in the ascending aorta and around the coronary button during the aortic anastomosis (Figure 1C). The remainder of the surgery was performed in a standard fashion. Intraoperative echocardiogram showed good biventricular function and satisfactory anatomy. Pulmonary artery pressure was mildly elevated. The patient had an uneventful first night. The day after surgery, the patient had a cardiac arrest and was resuscitated with venoarterial extracorporeal membrane oxygenation (ECMO) support with left ventricular (LV) venting. Analysis of blood Submitted September 20, 2019; Accepted February 04, 2020 Presented at 3rd Annual NeoHeart, March 2018, Fort Worth, Texas. Corresponding Author: Marcus P. Haw, 100 Michigan NE (MC248), Grand Rapids, MI 49503, USA. Email: marcus.haw@helendevoschildrens.org