Impacts of establishment of chest pain center on the door-to-balloon time and the short-term outcome after primary percutaneous coronary intervention of patients with ST segment elevated myocardial infarction / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the impact of the establishment of chest pain center (CPC) model based on the pre-hospital real-time tele-12-lead electrocardiogram on the door-to-balloon (D-to-B) time and short-term outcome after primary percutaneous coronary intervention (PPCI) of patients with ST-segment elevated myocardial infarction (STEMI).</p><p><b>METHODS</b>A regular CPC was established with pre-hospital transmitted real-time 12-lead electrocardiogram system for pre-hospital diagnosis of STEMI and enabled the STEMI patients to bypass the emergency room and directly treated in the catheter lab to shorten the D-to-B time. The mean D-to-B time, the short-term outcome and medical costs were compared in PPCI patients before (93 cases, group A) and after (149 cases, group B) the establishment of CPC.</p><p><b>RESULTS</b>After the establishment of CPC, the annual mean D-to-B time was significantly shortened [(127 ± 79) min in group A vs.(72 ± 23 )min in group B, P < 0.01], the shortest monthly mean D-to-B time was remarkably reduced in group B than in group A [(56 ± 11) min vs. (73 ± 14) min, P < 0.01]. The annual ratio of D-to-B below 90 minutes was significantly increased from 62.4% (58/93) in group A to 91.9% (137/149) in group B (P < 0.05) . The in-hospital mortality rate tended to be lower and the incidence of heart failure during hospitalization was significantly reduced in group B compared with group A [3.4% (5/149) vs. 6.5% (6/93), P > 0.05; 14.1% (21/149) vs. 24.7% (23/93), P < 0.05]. The length of hospital stay was slightly shortened from (8.98 ± 4.89) days to (7.79 ± 5.43) days (P > 0.05). Corrected mean medical cost went down by 9.4% (P < 0.05).</p><p><b>CONCLUSION</b>The establishment of CPC may significantly shorten the D-to-B time, improve the short-term outcome and reduce the hospitalization cost for PPCI patients with STEMI.</p>

Association between multi-noninvasive indexes and mild coronary stenosis / 中华心血管病杂志

<p><b>OBJECTIVE</b>To observe the changes of multi-noninvasive indexes including endothelial function, arterial flexibility, carotid intima-media thickness (IMT) and serum inflammatory cytokines in patients with mild coronary stenosis.</p><p><b>METHODS</b>One hundred and five patients were divided into three groups according to the result of coronary angiography: coronary heart disease (stenosis > or = 50% in at least one coronary segment), mild coronary stenosis (stenosis < 50% in at least one coronary segment) and control group (normal coronary). Brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI), reflecting arterial flexibility and the lower extremity vascular disease respectively, were measured by a Colin system, carotid artery IMT was detected echocardiographically. Serum levels of NO, vWF, hs-CRP were measured before coronary angiography in all patients.</p><p><b>RESULTS</b>baPWV [(1482 +/- 155) cm/s vs. (1249 +/- 158) cm/s] and carotid IMT [(0.88 +/- 0.18) mm vs. (0.72 +/- 0.20) mm] were significantly higher while serum levels of NO [(64 +/- 17) micromol/L vs. (83 +/- 17) micromol/L] was significantly lower in mild coronary stenosis group than those in control group (all P < 0.05). vWF, ABI and hs-CRP were similar between the two groups (all P > 0.05). Logistic regression analysis showed that NO, baPWV, smoking are independent predicting factors for mild coronary stenosis (all P < 0.05).</p><p><b>CONCLUSIONS</b>Endothelial dysfunction, reduction of the arterial flexibility as well as increased serum inflammation were associated with mild coronary stenosis.</p>

Clinical features of coronary artery spasm patients with or without myocardial bridge / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the clinical features of coronary artery spasm patients with or without myocardial bridge and explore the roles of endothelial dysfunction in these patients.</p><p><b>METHODS</b>One hundred eighteen patients undergone acetylcholine provoking test were divided into myocardial bridge (MB) group (n = 26) and non-myocardial bridge (NMB) group (n = 92). The results of acetylcholine test, treadmill exercise electrocardiography, stress myocardial perfusion scintigraphy, plasma level of endothelin-1 and nitric oxide were compared between MB group and NMB group.</p><p><b>RESULTS</b>Coronary artery spasm was induced in 21 patients in MB group (81%) and 52 patients in NMB group (57%, P < 0.05). Positive treadmill electrocardiography was obtained in 19 patients in MB group (73%) and 7 patients in NMB group (8%, P < 0.001). Ischemic perfusion defect in 20 (77%) and 9 patients (10%, P < 0.001) and reverse redistribution in 23 (88%) and 68 patients (74%, P > 0.05). Patients showed different clinical features in MB group and NMB group (more short-duration exertional angina and could not be readily released by nitroglycerine in MB group while more patients experienced long-lasting variant angina and symptoms could be readily released by nitroglycerine). Plasma endothelin-1 level was significantly higher [(132.1 +/- 6.5) ng/L vs. (108.5 +/- 8.2) ng/L, P < 0.01] while nitric oxide was significant lower [(84.7 +/- 17.5) ng/L vs. (99.8 +/- 18.2) ng/L, P < 0.05] in MB group compared to NMB group.</p><p><b>CONCLUSION</b>MB patients were prone to coronary artery spasm partly due to endothelial dysfunction. Patients with MB and coronary artery spasm also showed classic clinical symptoms and positive stress tests for ischemia.</p>

Relationship between dehydroepiandrosterone and arteriosclerosis in premenopausal and postmenopausal women / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the correlation between dehydroepiandrosterone and arteriosclerosis in premenopausal and postmenopausal women.</p><p><b>METHODS</b>Forty premenopausal and 40 postmenopausal women were examined for serum concentrations of dehydroepiandrosterone and intima-media thickness of the carotid artery, and the serum concentrations of lipids, estrogen, endothelin, and E-selectin were also measured.</p><p><b>RESULTS</b>Compared with premenopausal women, the mean intima-media thickness was increased but dehydroepiandrosterone and estrogen levels were decreased in postmenopausal women. A significant inverse correlation was detected between the intima-media thicknesses and dehydroepiandrosterone level. The postmenopausal women had decreased antioxidation and elevated low-density lipoprotein level.</p><p><b>CONCLUSION</b>Arteriosclerosis is more likely to occur in women with low dehydroepiandrosterone level which causes decreased antioxidation and elevation of blood lipid levels.</p>

A new synthetic tripeptide inhibits L-arginine transport in macrophages / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effect of a new synthetic tripeptide [Arg(NO(3))- Lys(OCH(3))- Arg(NO(3))] on L-arginine/NO pathway in the macrophage cell strain RAW246.7.</p><p><b>METHODS</b>The cultured macrophages exposed to lipopolysaccharide (LPS, 1 microg/L) treatment were randomly divided into 3 groups (n=6) and treated with distilled water, 1x10(-4) mol/L tripeptide and 1x10(-4) mol/L L-arginine, NG-monomethyl-L-arginine (L-NMMA) for 24 h, respectively. The macrophages were incubated for 24 h with LPS (1 microg/L) and in the presence of different concentrations of L-arginine (0 to 2 mmol/L), or in normal culture medium (containing 0.5 mmol/L L-arginine) for 24 h with LPS (1 microg/L) and in the presence of tripeptide of 0 to 10x10(-4) mol/L. The changes of [(3)H]-L-arginine transport and NO production from the macrophages were measured.</p><p><b>RESULT</b>NO release from macrophages incubated in the LPS-containing culture medium was 50 folds, and [(3)H]-L-arginine uptake 2.7 folds that in cells in normal culture medium. Tripeptide (1x10(-4) mol/L) inhibited [(3)H]-L-arginine transport and NO production by 67% and 71% respectively. The effect of tripeptide was stronger than L-NMMA (P<0.05). Extracellular L-arginine caused a concentration-dependent increase in nitrite production, which reached the maximum at concentrations above 0.5 mmol/L Km for nitrite production of 0.162+/-0.015 mmol/L and Vmax of 91.2+/-2.3 micromol/(24h.10(6) cells). L-arginine transport and NO production were inhibited by tripeptide, but their dose-dependent pattern of changes was different with EC50 of 0.21x10(-4) mol/L and 1.27x10(-4) mol/L, respectively.</p><p><b>CONCLUSIONS</b>Activation of macrophages with LPS induces nitrite accumulation in the culture medium, which is dependent on the presence of extracellular L-arginine. The tripeptide induces dysfunction of L-arginine/NO pathway in macrophages, potently inhibits L-arginine transport and competitively combine the active sites of nitric oxide synthase.</p>