Effect of the change of interstitia collagen and blood serum index on cardiac function in CD patients with different types of myocardial fibrosis

Aim: To investigate the change of interstitial collagen with varies pathogenic myocardial fibrosis and evaluate the clinical values of the serum extracellular matrix (ECM) for myocardial fibrosis. Methods: Collagen types I and III in myocardium specimens of 20 patients with rheumatic heart disease (RHD), 7 patients with dilated cardiomyopathy (DCM) and 10 patients with congenital heart disease (CHD) were observed by Sirius Red F3B (SR) staining. 5 healthy adult myocardium specimens composed the control group. The collagen volume fraction (CVF) was measured by imaging analysis system. The serum concentration of procollagen I (PCI), procollagen III (PC III), laminin (LN) and hyaluronic acid (HA) in patient group (n = 37) and in control group (n = 20) were measured. The correlation analysis was made with the area of fibrosis. Results: 1 The CVF in patients with RHD, DCM and CHD was 20.37 ± 8.32, 18.34 ± 2.84, 12.13 ± 3.26, respectively. There was significant difference between control group (5.47 ± 1.68) and patient group (t = -4.172 to 10.642, P < 0.01). 2 The ECM (μg/L) of serum in patient group (RHD group: PCI: 64.24 ± 21.28, PC III: 118.43 ± 36.32, LN: 116.77 ± 16.65, HA: 118.29 ± 37.69; DCM group: PCI: 60.56 ± 19.58, PCIII: 128.32 ± 40.21, LN: 115.66 ± 15.36, HA: 122.78 ± 35.72) were higher than those in control group (PCI: 49.08 ± 14.54, PC III: 70.28 ± 15.34, LN: 82.68 ± 13.60, HA: 65.73 ± 18.22), and there was significant difference (t = -6.462 to -11.426, P < 0.05). Meanwhile, the ECM concentration of serum had positive correlation with the area of myocardial fibrosis. Conclusion: Abnormal hyperplasia and reconstruction of collagen exist in myocardial fibrosis interstitial. The level of ECM in serum can reflect hyperplasia of collagen and be used as clinical index to evaluate myocardial fibrosis.