A male newborn, delivered at 38 weeks via emergency cesarean section for fetal distress, presents with multiple congenital anomalies. The pregnancy was complicated by polyhydramnios, and the maternal history includes gestational diabetes controlled with diet but no known teratogen exposure. At birth, the infant is small for gestational age, weighing 2.5 kg, and exhibits respiratory distress and cyanosis requiring immediate attention. On examination, the infant has a distended abdomen with no visible anal opening, a systolic murmur on cardiac auscultation, and thoracolumbar spinal curvature. Limb abnormalities include left radial hypoplasia and preaxial polydactyly of the right hand. He experiences feeding difficulties and choking during his first feeding attempt, with no passage of meconium within 24 hours of birth. Investigations reveal coiling of a feeding tube in the upper esophagus on chest X-ray. Abdominal ultrasound identifies left renal agenesis, while spinal X-rays show thoracic hemivertebrae. Limb X-rays confirm radial hypoplasia and an accessory digit on the right hand. Given these findings, what is the most likely cardiac defect associated with this baby’s condition?
