Lipoprotein(a) is associated with mitral annular calcification but not mitral regurgitation: A propensity-matched study of 66,292 pairs.

BACKGROUND

Lipoprotein(a) [Lp(a)] is a genetically determined cardiovascular risk factor increasingly linked to calcific valvular disease. Although its role in aortic stenosis is well established, the association between Lp(a) and mitral valve pathology, particularly mitral annular calcification (MAC), mitral stenosis (MS), and mitral regurgitation (MR), remains uncertain.

OBJECTIVE

To evaluate the association between elevated Lp(a) levels and mitral valve disease in a large, real-world cohort.

METHODS

We conducted a retrospective observational analysis using the TriNetX research network, including over 130,000 adults with available Lp(a) measurements. Patients with Lp(a) >50 mg/dL were propensity score matched 1:1 to those with Lp(a) <50 mg/dL across 54 demographic, clinical, and treatment variables. Valvular outcomes were defined using administrative codes. Kaplan-Meier survival estimates and log-rank tests were calculated in the matched cohorts. The primary outcome was MAC, with MR, MS, and mitral valve prolapse (MVP) as secondary outcomes. AS served as a positive control.

RESULTS

Each matched cohort included 66,292 patients. Elevated Lp(a) was significantly associated with the primary outcome of MAC (hazard ratio [HR] 1.330, 95% CI 1.172-1.509, P < .001). The positive control outcome of AS(Aortic stenosis) was also significant (HR 1.313, 95% CI 1.175-1.466, P < .001). No significant associations were observed for the secondary outcomes of MR (HR 1.006, 95% CI 0.940-1.077, P = .856), MS (HR 1.178, 95% CI 0.875-1.587, P = .280), or MVP (HR 1.035, 95% CI 0.863-1.241, P = .710).

CONCLUSION

In this large multicenter propensity-matched cohort, elevated Lp(a) was independently associated with MAC but not with MS, MR, or mitral valve prolapse. These findings support a potential role of Lp(a) in mitral annular calcification and highlight the need for prospective studies to clarify causality and clinical implications.