The correlation between carotid-femoral pulse wave velocity and composition of the aortic media in CAD patients with or without hypertension.

OBJECTIVES: To investigate the influence of hypertension on large artery elasticity and the microstructure of the ascending aortic media in patients with coronary artery disease (CAD), and the association between arterial compliance and composition of the ascending aorta. METHODS: 60 patients with CAD who underwent coronary artery bypass graft surgery were divided into two groups: 30 patients in a hypertension group and 30 patients in a non-hypertension group. Carotid-femoral pulse wave velocity (cfPWV) was measured by an automatic device (Complior, Artech, France). The severity of coronary atherosclerosis was assessed after selective coronary angiography using the Gensini score system. A quantitative study was conducted on ascending aorta specimens by histological and computer image analysis. RESULTS: cfPWV of the hypertension group was higher than that of the non-hypertension group. The relative content of collagen in the ascending aortic media of the hypertension group was higher than that of the non-hypertension group, while the relative content of elastin in the ascending aortic media of the hypertension group was lower than that of the non-hypertension group. cfPWV showed a positive correlation with relative contents of collagen in the ascending aorta and a negative correlation with relative contents of elastin in the ascending aorta in the two groups. CONCLUSIONS: Hypertension may raise the contents of collagen and decrease the contents of elastin in the ascending aortic media of patients with CAD, which in turn may decrease the patients' large artery compliance. cfPWV may reflect the quantitative changes of collagen and elastin in the ascending aortic media in CAD patients independently of hypertension.

Combination of raloxifene, aspirin and estrogen as novel paradigm of hormone replacement therapy in rabbit model of menopause.

AIM: To assess a novel hormone replacement therapy (HRT) paradigm using raloxifene, aspirin combined with estrogen in rabbit model of menopause. METHODS: Female New Zealand white rabbits were ovariectomized or sham-operated. The ovariectomized rabbits were divided into 7 groups: estradiol valerate (E(2)), raloxifene, aspirin, E(2) /raloxifene, E(2)/aspirin, E(2) /raloxifene/aspirin and vehicle. Two weeks after the operation, the rabbits were administered the above drugs for 12 weeks. Then, the mammary glands were examined histologically, uterus was weighted, and blood sample was collected for analyzing the levels of estrogen, serum lipids and monocyte chemoattractant protein (MCP)-1, and platelet aggregation. The aortic tissue was examined morphometrically. RESULTS: Compared with E(2) 0.1 mg·kg(-1)·d(-1) treatment alone, the pairing of raloxifene 10 mg·kg(-1)·d(-1) with E(2) significantly decreased the extent of mammary gland branches and ducts (5.53%±1.23% vs 15.4%±2.17%, P<0.01), as well as the uterine weight (2.16±0.35 g vs 4.91±0.75 g, P<0.01). However, E(2)/raloxifene or E(2) alone treatment significantly stimulated platelet aggregation relative to vehicle group. Addition of aspirin 5 mg·kg(-1)·d(-1) reduced platelet aggregation to almost the same level as the vehicle group. E(2) treatment exerted a positive effect on serum lipids and MCP-1, and a regression in aortic intimal plaque size compared to the vehicle. Raloxifene reinforced the positive effects of E(2). CONCLUSION: The combination of raloxifene, aspirin and E(2) exhibits positive lipid, MCP-1 and atherosclerotic responses with minimal stimulation of breast and uterine tissues as well as platelet aggregation in a rabbit model of the menopause.

Atherosclerotic plaque components characterization and macrophage infiltration identification by intravascular ultrasound elastography based on b-mode analysis: validation in vivo.

Intravascular ultrasound elastography (IVUSE) is a promising imaging technique for early investigation of vulnerable plaques. Compared to radiofrequency signal processing, digital B-mode analysis is simple and of higher portability. However, rare studies have been reported validating the latter technique in vivo. In this study, we developed an IVUSE computer software system involving semi-automatic border delineation and block-matching algorithm and validated the system in vivo. Seven minipigs were fed with atherogenic diet for 40 weeks. For each pig, the endothelium of one side of the renal arteries was denuded at the fifth week. With cross-correlation analysis, Lagrangian strain was calculated from two intravascular ultrasound images acquired in situ. Sixty regions of interests were selected from 35 elastograms matched well with the corresponding histological slices. Plaque types within these regions were classified as fibrous, fibro-fatty or fatty on Masson's trichrome and Oil-red O staining. Macrophage infiltration was also evaluated with immunohistology. Comparison between the mean strain value of the region of interest and the histological results revealed significant differences in strain values among different plaque types and non-diseased artery walls. The extent of macrophage infiltration was found to be correlated positively with strain values. For identification of fibro-fatty and fibrous plaques and macrophage infiltration, the system showed high sensitivity (93, 96 and 92%, respectively) and specificity (89, 76 and 66%, respectively), as revealed by receiver operating characteristic analysis. Our IVUSE system based on B-mode analysis is capable of characterizing fibrous and fibro-fatty plaques and macrophage intensity, thus holds potential for identifying vulnerable plaque.

[The role of atherosclerotic plaque stability and inflammation in the pathogenesis of acute coronary syndrome].

OBJECTIVE: To elucidate the effect of inflammation and coronary atherosclerotic plaque destabilization in the pathogenesis of acute coronary syndromes (ACS). METHODS: Twenty-eight patients with ACS and 13 patients with stable angina pectoris (SA) were examined by intravascular ultrasound (IVUS). Coronary plaque morphology and areas in culprit lesions were analyzed. The serum levels of hs-CRP, MMP-9, TIMP-1, sCD40L were also measured. RESULTS: Soft plaques were dominant in culprit lesions of ACS patients (71.4%, 20/28), and hard plaques were dominant in culprit lesions of SA patients [76.9% (10/13), P = 0.004]. At the culprit site, plaque area, plaque burden and remodeling index were all significantly larger in culprit lesions of ACS patients than those of SA patients (all P < 0.05). Positive remodeling was more frequent in ACS patients than in SA patients, whereas negative remodeling was more frequent in SA patients (P < 0.05). The serum levels of hs-CRP, MMP-9, sCD40L were higher in ACS group compared with SA group (P < 0.05, respectively). Moreover, hs-CRP level was positively correlated with MMP-9 (r = 0.671, P = 0.000) and sCD40L (r = 0.494, P = 0.008), respectively, in ACS patients. There was no difference in TIMP-1 between two groups (P = 0.234). CONCLUSIONS: These results suggest that structurally vulnerable plaques are essential element in the pathogenesis of ACS and inflammation might play an important role in plaque vulnerability.