Asymptomatic severe aortic stenosis — structured written assessment

SAQ 1 (10 marks)

Practice scenario. A 69-year-old woman is found to have aortic stenosis after a murmur is heard. Echocardiography shows a mean gradient of 52 mmHg, Vmax 4.6 m/s, aortic valve area 0.7 cm² and LVEF 60%.^[1] She is sedentary and says she has no symptoms.^[1]

1. How does ESC/EACTS 2025 define severe high-gradient AS, and how does that grading treat LV function and flow? (1)^[1]
2. What does the ESC/EACTS 2025 text say exercise testing can show in asymptomatic severe AS, and how should uncovered symptoms be handled? (2)^[1]
3. Give the two ACC/AHA 2020 exercise testing rows in AS, with COR and LOE. (2)^[3]
4. Her exercise test is normal and the Heart Team judges her procedural risk low. Give the ESC/EACTS 2025 row that applies, with class and level. (2)^[1]
5. She opts for surveillance. Give the ESC/EACTS 2025 follow-up interval and the ACC/AHA 2020 Table 5 echo interval for her. (2)^[1][2]
6. Name one service factor that ESC/EACTS 2025 says favours early intervention. (1)^[1]

Model answers — SAQ 1

1. Mean gradient ≥40 mmHg, Vmax ≥4.0 m/s and AVA ≤1 cm² (or ≤0.6 cm²/m²); high-gradient AS is considered severe irrespective of LV function and flow conditions (1 mark).^[1]
2. ESC/EACTS 2025: exercise testing can unmask symptoms and haemodynamic intolerance (fall in BP above 20 mm Hg) and is recommended for risk stratification in asymptomatic patients with severe AS (text; no class or level given) (1 mark).^[1] In roughly one-third of patients with severe AS who report no symptoms, it can uncover symptoms or reduced exercise capacity attributable to AS, and such patients should be treated as symptomatic (1 mark).^[1]
3. In asymptomatic patients with severe AS (Stage C1), exercise testing is reasonable to assess physiological changes with exercise and to confirm the absence of symptoms (COR 2a, LOE B-NR) (1 mark).^[3] In symptomatic patients with severe AS (Stage D1, aortic velocity ≥4.0 m/s or mean pressure gradient ≥40 mm Hg), exercise testing should not be performed because of the risk of severe hemodynamic compromise (COR 3: Harm, LOE B-NR) (1 mark).^[3]
4. Intervention should be considered in asymptomatic patients (confirmed by a normal exercise test, if feasible) with severe, high-gradient AS and LVEF of 50% or more as an alternative to close active surveillance, if the procedural risk is low (1 mark).^[1] ESC/EACTS 2025 Recommendation Table 4, Class IIa, Level A (1 mark).^[1]
5. ESC/EACTS 2025: follow up at least every 6 months, to detect early symptoms (using exercise testing if complaints are inconclusive) and any change in echocardiographic parameters, particularly LVEF (1 mark).^[1] ACC/AHA 2020 Table 5: echo every 6–12 months for severe asymptomatic AS (Stage C1, Vmax ≥4 m/s) (1 mark).^[2]
6. Either restricted local resources that may impede close surveillance, or long waiting lists that preclude prompt treatment when symptoms develop (1 mark).^[1]

SAQ 2 (10 marks)

Practice scenario. A 63-year-old man has severe aortic stenosis without symptoms on history or on an exercise test. Over 12 months his Vmax has risen from 4.1 to 4.5 m/s (mean gradient now 50 mmHg), and his CT aortic valve calcium score is 2600 AU.^[1] His LVEF is 58%. BNP and NT-proBNP, each measured twice, are 3.5 times the age- and sex-corrected normal range, with no other explanation found.^[1][3] The Heart Team judges his surgical and procedural risk low, and he wants a bioprosthesis.

1. Which parameters of the ESC/EACTS 2025 Class IIa, Level B asymptomatic row does he meet, and which does he not meet? (3)^[1]
2. Which ACC/AHA 2020 timing rows apply, with COR and LOE? (2)^[3]
3. Under ACC/AHA 2020, which procedure is recommended, and on which rows? (2)^[3]
4. Under ESC/EACTS 2025, which mode-of-intervention row applies, and how does the guideline define low surgical risk for it? (2)^[1]
5. What reason does the ACC/AHA 2020 supportive text give for preferring SAVR in asymptomatic patients with COR 2a indications? (1)^[3]

Model answers — SAQ 2

1. The row: intervention should be considered in asymptomatic patients with severe AS and LVEF of 50% or more if the procedural risk is low and one of its parameters is present (Class IIa, Level B).^[1] He meets severe valve calcification (ideally assessed by CCT) with Vmax progression of 0.3 m/s/year or more; ESC/EACTS 2025 Figure 7 footnote c gives severe valve calcification as an AVCS above 2000 in men (1 mark).^[1] He meets markedly elevated BNP/NT-proBNP: more than three times the age- and sex-corrected normal range, confirmed on repeated measurement without other explanation (1 mark).^[1] He does not meet very severe AS (mean gradient ≥60 mmHg or Vmax above 5.0 m/s) or LVEF below 55% without another cause (1 mark).^[1]
2. In asymptomatic patients with high-gradient severe AS (Stage C1) and low surgical risk, AVR is reasonable when serial testing shows an increase in aortic velocity ≥0.3 m/s per year (COR 2a, LOE B-NR) (1 mark).^[3] In apparently asymptomatic patients with severe AS (Stage C1) and low surgical risk, AVR is reasonable when the serum BNP level is more than 3 times normal (COR 2a, LOE B-NR) (1 mark).^[3]
3. SAVR: for asymptomatic patients with severe AS and rapid progression or an elevated BNP (COR 2a indications for AVR), SAVR is recommended in preference to TAVI (COR 1, LOE B-NR) (1 mark).^[3] He is under 65, and for symptomatic and asymptomatic patients with severe AS and any indication for AVR who are under 65 years of age or have a life expectancy over 20 years, SAVR is recommended (COR 1, LOE A) (1 mark).^[3]
4. SAVR is recommended in patients under 70 years of age, if the surgical risk is low (Class I, Level B) (1 mark).^[1] Footnote e: surgical risk based on STS-PROM and EuroSCORE II below 4% and Heart Team assessment (1 mark).^[1]
5. Published RCTs comparing TAVI and SAVR included only patients with symptoms attributable to severe AS (1 mark).^[3]