Coarctation and interrupted aortic arch — formative SAQs

Two formative SAQs on coarctation of the aorta and interrupted aortic arch in children: the neonate who collapses on day three of life with weak femoral pulses and metabolic acidosis, testing the prostaglandin-E1-first rule and the ductal-dependent mechanism; and the adolescent girl with coarctation, Turner syndrome and a bicuspid aortic valve, testing the syndromic associations, the four-limb blood-pressure examination and the lifelong follow-up.

Prompt

Coarctation and interrupted aortic arch

SAQ 1 — Neonatal collapse on day three (10 marks, 15 minutes)

A three-day-old term infant, previously feeding well, is brought to the emergency department with poor feeding, tachypnoea, mottled skin and oliguria. On examination the baby is shocked with cool peripheries, a heart rate of 180, a respiratory rate of 70, and a capillary refill of five seconds. The brachial pulses are strong but the femoral pulses are weak and delayed. Pre-ductal (right arm) saturation is 95% and post-ductal (leg) saturation is 72%. The blood gas shows a pH of 7.10 with a base excess of minus twelve and a lactate of 8 mmol per litre. A ductal-dependent arch obstruction is suspected. ^[4]

a) What is the most likely diagnosis, and what single bedside sign makes it most likely? (2 marks) ^[3]

b) Outline your immediate resuscitation, including the specific drug, its dose and its mechanism of action. Name the most important side effect and how you would manage it. (5 marks) ^[4]

c) Explain the pathophysiology of why this child was well for three days and then collapsed. (3 marks) ^[3]

References12Show

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[2]Kim YY; Andrade L; Cook SC Aortic Coarctation. Cardiol Clin, 2020.PMID 32622489
[3]Hede SV; DeVore G; Satou G; et al Neonatal management of prenatally suspected coarctation of the aorta. Prenat Diagn, 2020.PMID 32277716
[4]Bansal N; Balakrishnan PL; Aggarwal S Prostaglandin Infusion in Neonate With Severe Coarctation of the Aorta With Closed Ductus Arteriosus — A Case Report and Review of the Literature. World J Pediatr Congenit Heart Surg, 2020.PMID 31010402
[5]LaPar DJ; Baird CW Surgical Considerations in Interrupted Aortic Arch. Semin Cardiothorac Vasc Anesth, 2018.PMID 29774793
[6]Schreiber C; Mazzitelli D; Haehnel JC; et al The interrupted aortic arch: an overview after 20 years of surgical treatment. Eur J Cardiothorac Surg, 1997.PMID 9332928
[7]Burbano-Vera N; Zaleski KL; Latham GJ; et al Perioperative and Anesthetic Considerations in Interrupted Aortic Arch. Semin Cardiothorac Vasc Anesth, 2018.PMID 29742969
[8]Ron HA; Crowley TB; Liu Y; et al Improved Outcomes in Patients with 22q11.2 Deletion Syndrome and Diagnosis of Interrupted Aortic Arch Prior to Birth Hospital Discharge, a Retrospective Study. Genes (Basel), 2022.PMID 36672801
[9]Eckhauser A; South ST; Meyers L; et al Turner Syndrome in Girls Presenting with Coarctation of the Aorta. J Pediatr, 2015.PMID 26323199
[10]Wu Y; Jin X; Kuang H; et al Is balloon angioplasty superior to surgery in the treatment of paediatric native coarctation of the aorta: a systematic review and meta-analysis. Interact Cardiovasc Thorac Surg, 2019.PMID 30060099
[11]Toro-Salazar OH; Steinberger J; Thomas W; et al Long-term follow-up of patients after coarctation of the aorta repair. Am J Cardiol, 2002.PMID 11867038
[12]Sinning C; Zengin E; Kozlik-Feldmann R; et al Bicuspid aortic valve and aortic coarctation in congenital heart disease — important aspects for treatment with focus on aortic vasculopathy. Cardiovasc Diagn Ther, 2018.PMID 30740325