Characteristics and Quantitative Analysis of Myocardial Lymphatic Architecture in Patients with Different Types of End-Stage Heart Failure.

This study explored differences in morphology and distribution of myocardial lymphatic drainage ducts in patients with dilated cardiomyopathy (DCM), ischemic cardiomyopathy (ICM), and hypertrophic cardiomyopathy (HCM) in end-stage heart failure to reveal the relationship between the morphological distribution characteristics of myocardial lymphatic drainage ducts and different etiologies and these disease courses. Hearts of 24 patients (transplant recipients) who underwent heart transplantation and 1 normal heart were collected. Myocardial tissue from the anterior wall of the ventricle was taken and quickly frozen. Immunohistochemical and Western blotting techniques were used to detect the expression of LYVE-1, Podoplanin, and VEGFR-3 in cardiac tissue. Ink injection, immunohistochemical staining, and immunofluorescence double labeling techniques were used to detect the co-localization of three antibodies in hu-man heart tissue. Masson staining was used to observe the distribution and content of collagen fibers in the heart tissue of transplant recipients. Compared with the normal group, expression levels of LYVE-1 (p<0.05) and VEGFR-3 (p<0.001) in the DCM group were significantly increased. Expression level of LYVE-1 (p<0.05) was significantly increased in the ICM and HCM groups, but there was no significant change in the expression level of VEGFR-3. The expression level of Podoplanin in the normal group was higher than that in the heart failure groups, but the protein ex-pression results were the opposite. The expression levels of LYVE-1 and VEGFR-3 in the DCM and ICM groups showed an increasing trend with the progression of the disease, while the expression levels of Podoplanin showed a decreasing trend. The immunofluorescence results showed that on larger lymphatic vessels, LYVE-1 and VEGFR-3 were expressed on the inner side of the lymphatic lumen, while Podoplanin was expressed on the outer side, and there was co-localization between the two layers. Masson's staining results showed that the degree of myocardial fibrosis in the DCM group (p<0.01) and HCM group (p<0.001) increased, while there was no significant change in the ICM group (p<0.05). Positive expression intensity of LYVE-1, Podoplanin, and VEGFR-3 does not have a consistent quantitative relationship with different types of heart failure and the duration of the disease. The expression of three biomarkers confirms that DCM, ICM, and HCM have increased lymphatic vessel architecture compared to normal hearts, and the number of lymphatic vessels increases with prolongation of disease course.