Author: Amy Babb, MD - Yale University, School of Medicine - Yale New Haven Hospital
A baby is born at 31 weeks’ gestation, weighing 1.6 kg. He is diagnosed with a discrete coarctation of the aorta, normal sized aortic arch and normal intracardiac anatomy. Prostaglandin infusion is started to maintain systemic perfusion. The patient has no other congenital abnormalities. Surgical repair via thoracotomy is proposed. What strategy is MOST appropriate?
EXPLANATION
The optimal timing of coarctation repair in premature and low-birth-weight neonates remains challenging, particularly when balancing the potential benefits of growth against the risks of delaying surgery.1 Historically, low weight was associated with increased mortality and recurrent coarctation, leading some centers to delay repair to allow neonatal weight gain.1 However, multiple studies demonstrate that primary repair can be successfully performed at very low weights.2-5 In 2009, Burch et al. published a study looking at 167 infants <90 days old, including 29 patients weighing <2.5 kg, for coarctation repair via thoracotomy. Early mortality was 0.6%, and 5-year freedom from reintervention was similar in infants less than 2.5 versus greater than 2.5 kg (86% vs 89%).2 There was also no difference in survival and reintervention between patients who underwent surgery at 30 days of age or younger compared to patients between 31-90 days of age.2
More contemporary studies reinforce this approach.4,5 Chen et al. evaluated 14 neonates <2 kg, with a median operative weight of 1.8 kg (range 1.5–1.9 kg); there were no deaths, and only 2 patients required balloon dilation for recoarctation during long-term follow-up.4 Butler et al. studied 15 infants <2 kg, with a median operative weight of 1.585 kg; importantly, the smallest infants (<1.2 kg) underwent later repair without a reduction in recoarctation.5 The cohort had high rates of prematurity-related complications overall, including BPD (40%) and IVH (40%), particularly among the smallest infants who also underwent later repair.5 Delay itself was not proven to cause these noted complications, but the findings suggested that waiting for weight gain offered little benefit and may prolong exposure to the risks of prematurity.5
The 2024 Society of Thoracic Surgeons guideline supports basing the timing of coarctation repair on the severity of obstruction and the infant’s clinical condition rather than a predetermined weight threshold.1 Low weight and prematurity remain important risk factors, but they should inform perioperative risk assessment rather than serve as absolute reasons to postpone repair.1,5 Overall, current evidence does not support waiting until 3 kg or another arbitrary weight when a low-weight neonate has a clinically significant coarctation requiring repair.1,5
REFERENCES
1. Stephens EH, Feins EN, Karamlou T, et al. The Society of Thoracic Surgeons Clinical Practice Guidelines on the Management of Neonates and Infants With Coarctation. Ann Thorac Surg. 2024;118(3):527-544. doi:10.1016/j.athoracsur.2024.04.012
2. Burch PT, Cowley CG, Holubkov R, et al. Coarctation repair in neonates and young infants: is small size or low weight still a risk factor?. J Thorac Cardiovasc Surg. 2009;138(3):547-552. doi:10.1016/j.jtcvs.2009.04.046
3. Sudarshan CD, Cochrane AD, Jun ZH, Soto R, Brizard CP. Repair of coarctation of the aorta in infants weighing less than 2 kilograms. Ann Thorac Surg. 2006;82(1):158-163. doi:10.1016/j.athoracsur.2006.03.007
4. Chen Q, Fleming T, Caputo M, Stoica S, Tometzki A, Parry A. Repair of aortic coarctation in neonates less than two kilograms. Interdiscip Cardiovasc Thorac Surg. 2024;39(6):ivae185. doi:10.1093/icvts/ivae185
5. Butler V, Belhadjer Z, Gaudin R, Raisky O, Houyel L, Bonnet D. Outcomes after aortic coarctation repair in neonates weighing less than 2000 g. Arch Pediatr. 2023;30(8):567-572. doi:10.1016/j.arcped.2023.08.002