Prosthetic heart valves — structured written assessment

SAQ 1 (10 marks)

Practice scenario. A 64-year-old man had a new-generation bileaflet mechanical aortic valve implanted 8 years ago and takes warfarin alone, with no antiplatelet agent. He now has atrial fibrillation without mitral stenosis, an LVEF of 55%, no hypercoagulable state, no thrombotic event in the past year and no high bleeding risk, and needs an elective total hip replacement, a major non-cardiac operation. His general practitioner asks whether he could change to a DOAC.^[1][4][3][2]

1. Can he change to a DOAC? Give the ESC/EACTS 2025 row and the ACC/AHA 2020 rows, with class or COR and LOE. (2)^[1][3]
2. What INR target and range apply now under ESC/EACTS 2025 Table 10, and why? (2)^[1]
3. Does AF change his peri-operative plan under ESC/EACTS 2025 Recommendation Table 15? Give the row with its class and level. (2)^[1]
4. Give the ESC/EACTS 2025 row on stopping and restarting the VKA around major elective non-cardiac surgery. (2)^[1]
5. Under the ACC/AHA 2020 valve guideline, how does his AF bear on his INR target and on bridging for this operation? Give each row with its COR and LOE. (2)^[3]

Model answers — SAQ 1

1. No: ESC/EACTS 2025 says DOACs and/or DAPT are not recommended to prevent thrombosis in patients with an MHV (Class III, Level A); ESC 2024 AF excludes mechanical heart valves from its DOAC-preference row (1 mark).^[1][4] ACC/AHA 2020: dabigatran is contraindicated with a mechanical valve prosthesis (COR 3: Harm, LOE B-R), and anti-Xa DOACs have not been assessed and are not recommended (COR 3: Harm, LOE C-EO) (1 mark).^[3]
2. Table 10 (first-line treatment with VKA only) gives 2.5 (2–3) for a bileaflet or current-generation single-tilting aortic MHV without additional pro-thrombotic factors, and 3 (2.5–3.5) with them (1 mark).^[1] Table 10 lists AF with significant mitral stenosis, not AF alone, among its pro-thrombotic factors, with an inherited or acquired hypercoagulable state, LV dysfunction (LVEF under 35%) and a recent (under 12 months) major thrombotic event (cardioembolic stroke, deep vein thrombosis or pulmonary embolism); he has none of these and no high bleeding risk (for which footnote c, on the 2.5 (2–3) cell, says the target could be maintained at a lower interval of 2 (1.5–2.5)), so his target is 2.5 (2–3) (1 mark).^[1]
3. The Recommendation Table 15 thromboembolic risk factors (footnote e) are an MHV in the mitral or tricuspid position, older MHV generations in any position, an inherited or acquired hypercoagulable state, LV dysfunction (LVEF under 35%), AF with significant mitral stenosis, and a recent (under 12 months) major thrombotic event (cardioembolic stroke, deep vein thrombosis or pulmonary embolism); AF alone is not on the list (1 mark).^[1] With a new-generation aortic MHV and no other thromboembolic risk factors undergoing major non-cardiac surgery or invasive procedures, interruption (3–4 days before surgery) and resumption of VKA without bridging may be considered to reduce bleeding (Class IIb, Level B) (1 mark).^[1]
4. It is recommended to discontinue VKA at least 4 days before major non-cardiac elective surgery, aiming for an INR under 1.5 (1 mark).^[1] It is recommended to resume VKA treatment within 24 h after surgery, or as soon as considered safe (Class I, Level B) (1 mark).^[1]
5. ACC/AHA 2020 gives AF as an example of the added thromboembolic risk factors for which, with a mechanical AVR, a VKA is indicated to achieve an INR of 3.0 (COR 1, LOE B-NR) (1 mark).^[3] Its bridging row covers invasive procedures with a mechanical AVR and any thromboembolic risk factor, an older-generation mechanical AVR, or a mechanical mitral valve replacement.^[3] In those patients, it finds bridging during the preoperative interval when the INR is subtherapeutic reasonable on an individualised basis, weighing bleeding against thromboembolism prevention (COR 2a, LOE C-LD) (1 mark).^[3] Dated history, not marked: the superseded 2024 AHA/ACC perioperative guideline placed a bileaflet mechanical AVR with major risk factors for stroke, which include AF, in the moderate category of its Table 14.^[9] It stated that, although further RCTs are warranted, available data support limiting bridging to very high thrombotic risk patients on a VKA (for example, mechanical mitral valves), with careful consideration of bleeding risk to determine an individualised strategy.^[9] Its 2026 edition (PMID 42804570) supersedes it and is not held as text for this topic, so any changes could not be checked.

SAQ 2 (10 marks)

Practice scenario. A 70-year-old woman had surgical aortic valve replacement with a bioprosthesis 3 years ago. She has new exertional breathlessness. Her echocardiogram 2 months after surgery showed a mean gradient of 11 mmHg; today it is 34 mmHg, and the effective orifice area has fallen by more than 50%.^[1]

1. Classify this using ESC/EACTS 2025 Table 12, showing the criteria. (2)^[1]
2. Which three conditions must be distinguished, and which imaging confirms suspected valve thrombosis under ESC/EACTS 2025? (2)^[1]
3. If thrombosis is confirmed, what are the ESC/EACTS 2025 and ACC/AHA 2020 rows? (2)^[1][3]
4. If thrombosis is excluded and this is structural valve deterioration, give two ESC/EACTS 2025 rows on reintervention with their class and level. (2)^[1]
5. What does ESC/EACTS 2025 say about prosthesis–patient mismatch when a valve-in-valve procedure is planned for a degenerated aortic BHV? (2)^[1]

Model answers — SAQ 2

1. Severe haemodynamic valve deterioration: the mean transvalvular gradient has increased by 20 mmHg or more, resulting in a mean gradient of 30 mmHg or more (1 mark).^[1] And the EOA has fallen by 50% or more compared with the echocardiographic assessment performed 1–3 months post-procedure (1 mark).^[1]
2. If TTE findings are uncertain, the diagnosis should be confirmed by TOE and/or CCT to distinguish between thrombus, pannus and degeneration (1 mark).^[1] TOE and/or 4D-CT are recommended in suspected valve thrombosis to confirm the diagnosis (Class I, Level C) (1 mark).^[1]
3. ESC/EACTS 2025: OAC using a VKA is recommended in BHV thrombosis before considering reintervention (Class I, Level B) (1 mark).^[1] ACC/AHA 2020: with suspected or confirmed bioprosthetic valve thrombosis, haemodynamic stability and no contraindication to anticoagulation, initial VKA treatment is reasonable (COR 2a, LOE B-NR) (1 mark).^[3]
4. Reintervention is recommended in symptomatic patients with significant BHV dysfunction not attributable to valve thrombosis (Class I, Level C) (1 mark).^[1] Transcatheter, transfemoral valve-in-valve implantation in the aortic position should be considered with significant valve dysfunction at intermediate or high surgical risk with suitable anatomical and prosthesis features, as assessed by the Heart Team (Class IIa, Level B) (1 mark).^[1]
5. Valve-in-valve implantation, particularly TAV-in-SAV, increases the risk of severe PPM, which has been linked to adverse outcomes in observational studies (1 mark).^[1] When considering valve-in-valve for a degenerated aortic BHV, the possibility of creating PPM in small valves should be anticipated and may affect the intervention or valve selection (1 mark).^[1]