Paeds Cases · cardiology
Atrioventricular septal defect — clinical case
Clinical case of a four-month-old girl with Down syndrome and a complete atrioventricular septal defect presenting in heart failure, illustrating anatomy, the pulmonary vascular window, and early surgical repair.
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Prompt
A four-month-old girl with Down syndrome is referred by her general practitioner for poor weight gain — she has dropped from the 25th to below the 3rd centile — tachypnoea, and two hospital admissions for bronchiolitis. Her mother describes exhausting feeds lasting 45 minutes with sweating. On examination she is tachypnoeic at 70 breaths per minute with subcostal recession, has a hyperactive precordium, a grade 3/6 pansystolic murmur at the lower left sternal edge, and a loud, palpable pulmonary component to the second heart sound. Her ECG shows a superior QRS axis of minus ninety degrees.
Case summary
This infant with Down syndrome presents with the classic constellation of a complete atrioventricular septal defect: failure to thrive, recurrent respiratory infections, the physical signs of a large left-to-right shunt with pulmonary hypertension, and the pathognomonic superior QRS axis. The combination of trisomy 21 and this clinical picture makes a complete AV canal the working diagnosis until echocardiography confirms it. [1]
References3ShowHide
- [1]Craig B Atrioventricular septal defect: from fetus to adult. Heart, 2006.PMID 17105897
- [2]Calabrò R, Limongelli G Complete atrioventricular canal. Orphanet J Rare Dis, 2006.PMID 16722604
- [3]Bergström S, Carr H, Petersson G, et al Trends in congenital heart defects in infants with Down syndrome. Pediatrics, 2016.PMID 27252035