Remodeling of intramyocardial tissue capillaries density depending on age, sex and cause of death.

AIM: Aging together with the wide range of diseases causing death are ones of the influential factors of cardiac wall remodeling regarding both their structural and functional features. The authors compared the changes of myocardial interstitial capillary network density (vascular density - VD) between the main regions of the cardiac wall during patients' ageing and depending on patients' cause of death. PATIENTS, MATERIALS AND METHODS: Five cross-sections from epicardium to endocardium [left ventricle wall (LVW): anterior segment (LV_AW), lateral segment (LV_LW), and posterior segment (LV_PW); interventricular septum (IVS); and right ventricle wall (RVW)] were collected during necropsies from 95 patients died with different ages (AP_01, 0-24 years; AP_02, 25-44 years; AP_03, 45-64 years; and AP_04, >64 years) and with different types of causes of death (V_P - vascular diseases, NV_P - non-vascular diseases, and S∕V_Dth - suspect∕violent cause of death, considered also control group - CG) in the hospital. Tissue samples were processed classically and immunomarked with anti-cluster of differentiation 34 (CD34) antibody. Glass slides were transformed into virtual slides. The VD was determined with a dedicated built program. Mean values (AVs) were compared with Pearson's correlation test. RESULTS: On one hand, VD increased slowly from youth to elderly in LV_Ws and decreased with age in the IVS and RVW. It had the lowest values in LV_Ws till AP_03 and in RVW in elderly. The highest values were in RVW till 44 years and then in IVS. VD had higher values in women than in men along the main regions of the cardiac wall and a divergent behavior, with age, in the two sexes. Thus, in men, VD had an increasing trend with age from LV_AW to RVW [correlation matrix (CM) positive, p-value >0.05] whereas in women, the trend was decreasing with age from LV_AW to RVW (CM negative, p-value >0.05), excepting IVS where it increases (CM positive). On the other hand, the VD had lowest values in V_P group and highest values in CG in general and in both sexes. Its values increased from LVW to RVW in V_P group and CG and decreased in NV_P group in general and in both sexes. They also increased from LV_AW toward LV_PW in all groups of COD and in both sexes. The VD AVs were higher in females than in males in CG and NV_P group and higher in males than in females in V_P group. Its values were lowest in both sexes in V_P group but highest in men in NV_P group and in women in CG. CONCLUSIONS: VD and is remodeling with aging in different ways both along the cardiac wall's regions and in the two sexes, being generally higher in females than in males. The causing death diseases determine different pathways of interstitial capillary network remodeling both along the different regions of the cardiac wall and in the two sexes, the most important being the capillary density decrease in vascular diseases as compared with all other causes of death.