Abstract Background Lipoprotein(a) [Lp(a)] is a genetically determined risk factor for myocardial infarction and aortic valve stenosis, and elevated Lp(a) levels are associated with increased risk of heart failure. While part of this heart failure risk is mediated through atherosclerotic and valvular disease, other pathological pathways may also contribute to the association between Lp(a) and heart failure. Purpose To assess if Lp(a) levels and corresponding LPA genotypes are associated with echocardiographic measures of left ventricular structure and function in the general population. Methods We included 3,427 participants from an observational general population study who underwent protocol echocardiography between 2011-15 and had an available measurement of Lp(a) and LPA genotypes. Lp(a) was measured in 1991-94 and 2001-03 using well-validated assays with the most recent measurement used for the present analysis. Participants were divided into groups based on quartiles of Lp(a) with the top quartile further stratified to capture those above the 90th percentile. For genetic analysis, participants were grouped based on kringle IV type 2 [KIV-2] repeat corresponding to plasma Lp(a) percentile groups. Linear regression models were used to estimate β-coefficients for echocardiographic measures associated with Lp(a) levels and genotypes, while logistic regression models were used to estimate odds ratios for cardiac dysfunction or remodeling. All models were adjusted for age and sex. Results Mean age was 63±14 years and 44% were male. Median plasma Lp(a) was 18 mg/dL [IQR 10-40], median number of KIV-2 repeats were 36 [30-40], 102 (3%) were rs3798220 minor allele carriers and 467 (14%) were rs10455872 carriers. Mean left ventricular ejection fraction [LVEF] was 56.0±6.6% and we had 99% power to detect an absolute LVEF difference of 2% between those with Lp(a) levels above the 90th percentile (corresponding to >75 mg/dL) compared with those below the 25th percentile (<10 mg/dL). Mean absolute global longitudinal strain (GLS) was 19.2±2.7% and we had 99% power to detect an absolute difference of 1%. However, we found no statistically significant differences in echocardiographic measures according to Lp(a) levels or LPA genotypes (Table 1). The prevalence of impaired LVEF was 16%, and we had <20% power to detect an odds ratio of 1.2 for those with Lp(a) above the 90th percentile compared with those below the 25th percentile. We found no significant associations between odds for cardiac dysfunction or left ventricular hypertrophy and Lp(a) levels or LPA genotypes (Table 2). Conclusion Elevated Lp(a) levels and corresponding LPA genotypes were not associated with echocardiographic measures of left ventricular structure and function in this general population cohort. While we did not have sufficient power to detect associations between Lp(a) and cardiac dysfunction, our findings do not support a substantial effect of Lp(a).
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