Comparison of intimal thickening of Chinese and New Zealand coronary arteries

Comparison of the endothelial surface and subjacent elastic lamina of anterior descending coronary arteries at the location of atheromatous lesions with internal thoracic arteries of the same subjects: a scanning electron microscopic study

AIM

Current theories fail to explain the localisation of atheromatous lesions or their variable incidence in different arteries of the same subject. The objective of this study was to compare by scanning electron microscopy (SEM) the endothelial surface and the subjacent elastic lamina of human coronary arteries at the location of areas showing infiltration by lipid and cells, with the same components of internal thoracic arteries of the same subjects.

METHODS

The endothelial surface and the subjacent elastic lamina of localised atheromatous areas of 146 anterior descending coronary arteries were compared with the same structural components of the internal thoracic arteries of the same subjects, using SEM, transverse paraffin sections and freeze-fracture. Some arteries were digested with formic acid to destroy the endothelium and interstitial tissue, and reveal the elastin fibre structure of the elastic laminae.

RESULTS

Coronary arteries showed localised defects of the endothelial surface and of the elastin fibre structure of the subjacent elastic membrane, with the presence of lipid and cells in transverse sections of the intima. Internal thoracic arteries showed such changes only rarely, more particularly in older age groups.

CONCLUSIONS

In localised areas of the coronary arteries showing infiltration of the wall by lipid and cells, there were imperfections of the endothelial surface and of the elastin fibre structure of the subjacent elastic lamina. These imperfections were not in general present in the endothelial surface, or subendothelial elastic lamina of the internal thoracic arteries in age groups below 50, and only rarely in older subjects.

Gray scale and power Doppler sonography of normal cervical lymph nodes: comparison between Chinese and white subjects

OBJECTIVE

To investigate the racial difference in gray scale and power Doppler sonography of cervical lymph nodes between white and Chinese subjects.

METHODS

Twenty healthy white subjects and 20 healthy Chinese subjects had sonographic examination of the neck. They were age and sex matched. Lymph nodes were evaluated for their number, size, site, echogenic hilus, vascular pattern, degree of vascularity, blood flow velocity, and vascular resistance.

RESULTS

A total of 184 lymph nodes were detected in the 20 white subjects, and 196 lymph nodes were found in the 20 Chinese subjects. There were no significant differences in the number, size, and distribution of the lymph nodes between the 2 populations. One hundred ninety-six region- and size-matched lymph nodes were selected from the 2 groups of subjects (98 nodes from each group) for evaluation of echogenic hilus, vascular pattern, degree of vascularity, blood flow velocity, and vascular resistance. There was no significant difference in the gray scale and vascular features of cervical nodes between white and Chinese subjects.

CONCLUSIONS

There is no significant racial difference in the gray scale appearance of cervical lymph nodes. Unlike some other body regions, there is no significant vascular difference between white and Chinese populations. Results on power Doppler and gray scale sonographic assessment of cervical lymphadenopathy reported in previous studies may be applicable in both populations.

Clustering of cardiovascular risk factors with diabetes in Chinese patients: the effects of sex and hyperinsulinaemia

OBJECTIVE

This study was designed to investigate factors which affect the clustering of cardiovascular risk factors with diabetes in Chinese patients.

RESEARCH DESIGN AND METHODS

Six hundred and fifty-four patients with diabetes were assessed comprehensively for diabetes complications and cardiovascular risk factors in a metropolitan hospital in Beijing, China. Insulin resistance and secretion were also evaluated by measurement of glucose and insulin levels before and after a meal tolerance test. Results were analysed according to patient groups stratified by the number of cardiovascular risk factors coexisting with diabetes.

RESULTS

Cardiovascular risk factors were common in Chinese diabetic patients. The clustering of three or more of these factors with diabetes occurred more often than by chance alone and was associated with postprandial hyperinsulinaemia. Patients with a high number of risk factors were more prone to macrovascular events but did not have higher albuminuria. Using the commonly adopted lower threshold for diagnosing obesity and central obesity in women, there were more women with multiple risk factors. However, this disappeared if the same criteria were used for men and women. Even in the presence of diabetes, cardiovascular risk factors were inadequately controlled in most patients.

CONCLUSIONS

The concurrence of diabetes and other cardiovascular risk factors which constitute the metabolic syndrome is a common phenomenon in urban Chinese diabetic patients. It is associated with hyperinsulinaemia and possibly the female sex. This study emphasises the importance of public health measures to control cardiovascular risk factors in patients with diabetes.

A comparison of coronary arteries from Japanese and NZ subjects

This paper describes a comparison of the anterior descending branch of the left coronary artery from 198 Japanese subjects of ages less than 60 yrs, with 301 New Zealand individuals of similar ages. The object of the study was to determine whether there were structural differences present which could be partially responsible for the low incidence of atherosclerosis in Japanese as well as the known low blood lipid levels. It was found that the internal elastic lamina of Japanese coronary arteries was less well formed at birth than that of NZ subjects. Intimal thickening was greater in Japanese coronary arteries from birth to the end of the first decade, but increased less rapidly with age, and was only about half as great as that of NZ vessels in the older age groups. The thickened intima of Japanese arteries was more uniform round the circumference of the vessel, the luminal surface was better formed with more stainable elastin present subjacent to the endothelial cells, and there was less evidence of mural thrombosis. NZ arteries showed pronounced eccentricity of the intima, more extensive lipid deposits, a poorly defined luminal surface, and frequent evidence of mural thrombosis.