Coarctation of the aorta in adults — structured viva

Stem

Practice viva. The examiner asks you to describe coarctation of the aorta in adults: how to judge significance, who needs repair and how, and what follow-up looks like after repair.^[1][2][3]

Branch A — What it is and how to grade it

Examiner: What is coarctation, and how do you decide that it is significant?^[1][2]

Strong answer:

• ESC 2020 considers coarctation part of a generalised arteriopathy, not only a narrowing of the aorta; it occurs as a discrete stenosis or a long hypoplastic arch segment, typically where the ductus arteriosus inserts, and only in rare cases ectopically.^[1]
• ESC 2024: a systolic non-invasive gradient between upper and lower extremities, an abnormal ABI, or an invasive peak-to-peak gradient ≥20 mmHg indicates significant coarctation, and with collaterals or decreased LV function gradients or ABI may underestimate severity.^[3]
• ESC 2020 (dated) also counted a systolic limb gradient of ≥20 mmHg, weak or absent leg pulses or radiofemoral delay, and a catheter peak-to-peak gradient ≥20 mmHg in the absence of well-developed collaterals.^[1]
• ACC/AHA 2025 Table 25 (features suggestive of hemodynamic significance) lists an upper-to-lower extremity systolic gradient >20 mm Hg; on TTE a Doppler mean gradient >20 mm Hg, a corrected maximum instantaneous gradient >20 mm Hg, and a diastolic tail in the descending aorta with diastolic forward flow in the abdominal aorta; a catheter peak-to-peak gradient >20 mm Hg; and on MRA/CTA an aortic isthmus ratio of <0.5–0.7 and collateral arteries.^[2]
• Its footnotes say gradients may be lower with LV dysfunction, severe aortic stenosis or extensive collateral arteries, and that in repaired coarctation Doppler gradients may be elevated even without narrowing.^[2]

Follow-up: What is the aortic isthmus ratio, and when does it matter?^[2]

• ACC/AHA 2025: the ratio of the aortic isthmus (the smallest coarctation diameter) to the descending aorta at the level of the diaphragm; expert consensus generally uses <0.5, and recent empirical data suggest <0.7 may be optimal for recommending repair.^[2]
• Anatomic severity can be used when the gradient may underestimate severity, for example with severe LV systolic dysfunction, severe aortic stenosis or extensive collaterals.^[2]

Branch B — Repair

Examiner: A 35-year-old hypertensive woman has an increased upper-to-lower limb systolic gradient, an anatomically significant native coarctation on CMR and an invasive peak-to-peak gradient of 28 mmHg; stenting is technically feasible. What do the guidelines say?^[3][2]

Strong answer:

• ESC 2024: repair (surgical or endovascular) is indicated in patients with hypertension with an increased non-invasive upper-to-lower limb gradient confirmed invasively (peak-to-peak >20 mmHg), with a preference for stenting when technically feasible (Class I, Level C); the ESC 2020 row says the same with ≥20 mmHg (Class I, Level C).^[3][1]
• ACC/AHA 2025: surgical or transcatheter stent therapy is recommended for anatomically and hemodynamically significant native or repaired coarctation to prevent irreversible LV dysfunction from chronic pressure overload (COR 1, LOE B-NR).^[2]
• Its supporting text says surgical or transcatheter repair should be by an operator with ACHD expertise.^[2]
• On choice of technique, ESC 2024 calls covered stenting the first-choice treatment, with a tube graft preferred if stenting is less suitable; ACC/AHA 2025 says immediate results are similar but limited long-term data suggest more reintervention and less complete LV reverse remodeling after stenting, so therapy is individualised.^[3][2]

Follow-up: What if she were normotensive?^[1][3]

• With an increased non-invasive gradient confirmed invasively, ESC 2024 says endovascular treatment should be considered when technically feasible (Class IIa, Level C), as did ESC 2020 for stenting (Class IIa, Level C).^[3][1]
• With ≥50% narrowing relative to the aortic diameter at the diaphragm and an invasive gradient <20 mmHg, ESC 2020 says stenting may be considered when technically feasible (Class IIb, Level C); ESC 2024 Recommendation Table 69 has no row for that situation.^[1][3]

Branch C — After repair

Examiner: Her stent procedure went well. What happens now?^[3][2]

Strong answer:

• Lifelong follow-up: ESC 2024 recommends regular imaging of the aorta with CCT/CMR every 3–5 years, adapted to clinical status and previous imaging (Class I, Level B), and ACC/AHA 2025 recommends periodic cross-sectional imaging to screen for recurrent coarctation, aneurysms and complications of repair including stent fracture (COR 1, LOE B-NR).^[3][2]
• Because she has a stent, ACC/AHA 2025 says CT angiography should be used rather than CMR, because of stent artefacts on CMR.^[2]
• Hypertension is common even after successful treatment (ESC 2020); ACC/AHA 2025 recommends resting upper and lower extremity blood pressure at routine assessment to screen for hypertension and residual or recurrent coarctation (COR 1, LOE B-NR), calls ambulatory measurement reasonable to diagnose hypertension and monitor response to antihypertensive therapy and exercise testing reasonable to screen for exercise-induced hypertension (both COR 2a, LOE B-NR), and recommends GDMT to maintain controlled resting and ambulatory blood pressure in native or repaired coarctation with hypertension without hemodynamically significant coarctation (COR 1, LOE B-NR).^[1][2]

Follow-up: Would you screen her brain for aneurysms?^[2][3]

• The bodies differ: ACC/AHA 2025 says screening by brain MR or CT angiography may be considered to guide management (COR 2b, LOE B-NR), whereas ESC 2024 says there is presently no evidence supporting screening in asymptomatic patients and ESC 2020 says routine screening in asymptomatic patients is not recommended.^[2][3][1]
• ESC 2020 says imaging of the intracerebral vessels is indicated with symptoms and/or clinical manifestations of aneurysms or rupture.^[1]