Background and aim: The association between high plasma Lp(a) lipoprotein and coronary heart disease has been confirmed in numerous case/control and prospective studies. A high Lp(a) level has also been shown to be an independent genetic risk factor, while its inverse relationship with TGF-beta 1 has suggested that it may interfere with plasmin-mediated activation of TGF-beta 1 and result in increased endothelial activation, as well as migration and proliferation of vascular smooth muscle cells. The aim of this study was to evaluate Lp(a) and TGF-beta 1 and their interactions in patients with first acute myocardial infarction (AMI).
Methods and results: A total of 107 patients with first AMI and 103 age and sex-matched controls were studied. Very good agreement was found between QEI and RIA determinations of Lp(a) (p < 0.0001). Lp(a) levels were significantly elevated in cases (QEI: p < 0.031; RIA p < 0.002 respectively). Division by gender gave statistically significant differences in females only. Plasma levels of the active form of TGF-beta 1 were decreased in cases, though significantly (p < 0.029) in males only.
Conclusions: Serum concentrations of Lp(a) and TGF-beta 1 are significantly altered in AMI patients. The differences are gender-dependent: Lp(a) is higher in females, and TGF-beta 1 is lower in males. Increased Lp(a) levels are accompanied by decreased active TGF-beta 1 levels and this inverse correlation is statistically significant (p < 0.001).