Abstract of the day - Does lipoprotein(a) play a role in bioprosthetic aortic valve degeneration?
25 Aug 2023
Abstract of the Day
An association between elevated serum lipoprotein(a) [Lp(a)] levels and aortic valve stenosis is well established.1 As native aortic stenosis and bioprosthetic aortic valve degeneration share similar pathological mechanisms, researchers from Mayo Clinic Hospital (Phoenix, USA) sought to investigate if serum Lp(a) is linked to bioprosthetic aortic valve degeneration.
As presented today by Doctor Francois Marcotte, a retrospective multicentre study was conducted in 211 consecutive patients who underwent a bioprosthetic aortic valve replacement and had a preoperative serum Lp(a) measurement. Mean age was 74 years, 72% were male and 30% underwent transcatheter aortic valve replacements. Transthoracic echocardiography was performed following the aortic valve replacement and at follow-up (after a median [IQR] of 5.0 [3.7] years). Significant bioprosthetic valve degeneration was defined as either: an increase >10 mmHg in mean bioprosthetic aortic valve gradient from baseline status plus a decrease in effective orifice area, a decrease in Doppler velocity index and exclusion of clinically thrombotic leaflet thickening; or new moderate or severe prosthetic aortic regurgitation if the main component was not periprosthetic.
Bioprostheses degeneration was observed in 15.6% patients at follow-up. Of note, median serum Lp(a) levels were significantly higher in patients affected by degeneration compared with non-affected cases (50.0 vs 15.7 mg/dL; p=0.003). Furthermore, in regression models, high Lp(a) levels (≥30 mg/dL) were associated with degeneration both in a univariate analysis (odds ratio [OR] 4.8; 95% CI 2.2–10.9; p<0.001) and in multivariate analysis (adjusted for age, sex, hypertension, smoking, patient prosthesis mismatch, creatinine levels and body surface area) (OR 5.2; 95% CI 2.1–12.8; p<0.001).
The authors highlighted the increasing importance of accurately predicting bioprosthetic aortic valve degeneration and the need to develop novel methods and treatments to increase durability. Whether lowering Lp(a) can reduce bioprostheses degradation is an intriguing question for future studies.
- Thomas PE, et al. Eur Heart J. 2023;44:1449–1460.