Elevated lipoprotein(a) levels in rheumatic heart valvular disease: A new link?

Abstract

Rheumatic heart valvular disease (RHVD) is primarily characterized by immune-mediated damage following infection with Streptococcus pyogenes, leading to inflammation and subsequent valvular dysfunction. Traditionally, the focus has been on the immunological aspects of this disease; however, emerging evidence suggests that lipoprotein(a) [Lp(a)] may play a crucial role not only in atherosclerosis but also in the pathophysiology of calcific aortic valve disease. Given the inflammatory nature of RHVD and the pro-inflammatory and pro-calcific properties of Lp(a), this study aimed to investigate the relationship between serum Lp(a) levels and the severity of RHVD. In this cross-sectional study, we included 40 RHVD patients and 40 age- and sex-matched controls. Serum Lp(a) analysis was performed in all patients. We analyzed demographic and echocardiographic parameters and the relationship between serum Lp(a) concentrations and echocardiographic parameters. The mean age of the patient population was 50 ± 11 years and 47 (72%) were female. Lp(a) was higher in the RHVD group than in the control group (21 [19-49] vs. 17 [12-19] mg/dL; p < 0.001). Serum Lp(a) correlated positively with left atrial diameter (rho = 0.438; p = 0.005), estimated pulmonary artery systolic pressure (rho = 0.390; p = 0.019), Wilkins score (rho = 0.482; p = 0.002), number of valves involved (rho = 0.397; p = 0.011), aortic regurgitation grade (rho = 0.373; p = 0.018) and negatively correlated with mitral valve area (rho = -0.413; p = 0.008). In conclusion, serum Lp(a) concentrations were higher in patients with RHVD than in the control group and were positively correlated with disease severity indicators, including mitral stenosis grade, Wilkins score, aortic regurgitation grade, left atrial diameter, and estimated pulmonary artery systolic pressure.