Structural Valve Deterioration
Definition
Structural valve deterioration (SVD) refers to intrinsic permanent change in a prosthetic heart valve (surgical or transcatheter) causing haemodynamic impairment. The 2025 ESC/EACTS guidelines provide unified definitions distinguishing haemodynamic SVD from other prosthetic valve complications (thrombosis, pannus, patient-prosthesis mismatch, endocarditis, paravalvular leak).
Key Concepts
Unified SVD Definitions (2025)
Haemodynamic SVD for aortic prostheses:
- Moderate SVD: Mean PG increase ≥10 mmHg from baseline AND absolute mean PG ≥20 mmHg (in the absence of significant paravalvular regurgitation)
- Severe SVD: Mean PG increase ≥20 mmHg from baseline AND absolute mean PG ≥40 mmHg
Mitral prostheses: Parallel definitions using transmitral mean gradient thresholds sources/vhd-esc-2025 very high
Follow-up Protocol for Prosthetic Valves — ESC 2025
- BHV: TTE within 3 months of implantation, at 1 year, then annually — or sooner if new symptoms
- MHV: Cinefluoroscopy and/or CCT if valve thrombus or pannus is suspected; TOE for any suspected dysfunction or endocarditis
- GLS and strain imaging can detect early LV dysfunction in prosthetic valve patients before thresholds are met
- All patients with prosthetic valves require lifelong clinical and echo follow-up sources/vhd-esc-2025
very high
Follow-up Protocol for Prosthetic Valves — ACC/AHA 2020
- Surgical BHV (Class IIa C-LD): TTE at 5 and 10 years after implantation, then annually, even without symptoms — ~30% develop haemodynamic dysfunction by 10 years
- Bioprosthetic TAVI (Class IIa C-LD): Annual TTE is reasonable given emerging durability data
- Mechanical valves: Routine annual TTE not needed if baseline study is normal and no clinical change
- Risk factors for accelerated SVD (<5 years): age <60 years at implantation, smoking, diabetes mellitus, CKD, initial mean gradient ≥15 mmHg
- Up to 13% of patients with surgical aortic BHV develop haemodynamic dysfunction at a median 6.7–9.9 years sources/VHD-AHA-2020
very high
Hypo-Attenuated Leaflet Thickening (HALT)
- Detected by CCT as thickening of transcatheter valve leaflets; represents subclinical valve thrombosis
- May reduce leaflet motion and increase gradients
- Associated with higher risk of stroke in some observational series
- Management: OAC (VKA or DOAC) if HALT detected and haemodynamically significant
Clinically Significant Valve Thrombosis
- Acute or subacute obstruction of mechanical or biological prosthesis
- Management: thrombolysis for obstructive left-sided MHV thrombosis (if no contraindication); surgery for high-risk thrombolysis candidates; anticoagulation for non-obstructive thrombosis
- Imaging critical: CCT and/or fluoroscopy to distinguish thrombosis from pannus
Non-Structural Dysfunction
- Prosthesis-patient mismatch (PPM): Indexed EOA too small for patient BSA — may lead to persistently elevated gradients post-implantation; severe PPM (iEOA <0.65 cm²/m²) is independently associated with adverse outcomes
- Paravalvular leak (PVL): More common after TAVI than SAVR; haemolysis and HF if severe; transcatheter closure should be considered for suitable PVLs (Class IIa) sources/vhd-esc-2025
very high
Prosthetic Valve Selection
- MHV: Considered in patients <60 years (aortic) or <65 years (mitral) with long life expectancy and no contraindication to lifelong OAC; Class IIa for estimated long life expectancy
- BHV: Preferred in patients >65 years (aortic) or >70 years (mitral); high bleeding risk, estimated short life expectancy, women planning pregnancy, or where stable INR is unlikely
- Valve-in-valve TAVI is an established option for BHV degeneration — early SVD data for TAVI valves themselves are limited beyond 8–10 years sources/vhd-esc-2025
very high
Contradictions / Open Questions
- Long-term durability of TAVI valves in younger patients is the critical unanswered question — 10+ year data are just beginning to emerge
- The optimal management of asymptomatic HALT detected on CCT surveillance is unclear — not all HALT progresses or causes adverse outcomes
- Valve-in-valve TAVI for surgical BHV degeneration carries risk of high residual gradients (PPM within a ring) — optimal sizing and device selection require further study
- SVD definitions remain heterogeneous in the literature; the 2025 unified definitions aim to standardise reporting but have not yet been prospectively validated across all valve types and positions
Connections
- Related to concepts/Valvular-Heart-Disease
- Related to concepts/TAVI
- Related to concepts/Aortic-Stenosis
- Related to concepts/Primary-Mitral-Regurgitation