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>

Evaluation on the efficacy and safety of domestic bivalirudin during percutaneous coronary intervention / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Bivalirudin was widely used as an anticoagulant during coronary interventional procedure in western countries. However, it was not available in China before this clinical trial was designed. This randomized, single-blind and multicenter clinical trial aimed to evaluate the efficacy and the safety of domestic bivalirudin during percutaneous coronary intervention (PCI).</p><p><b>METHODS</b>A randomized, single-blind, multicenter trial was designed. Elective PCI candidates in five centers were randomized into a bivalirudin group and a heparin group, which were treated with domestic bivalirudin and non-fractional heparin during the PCI procedure. The efficacy was evaluated by comparing the activated coagulation time (ACT), the procedural success rate (residual stenosis < 20% in target lesions without any coronary artery related adverse events within 24 hours after PCI), and the survival rate without major adverse cardiac events at 30 days after PCI between the two groups. Safety was evaluated by the major/minor bleeding rate.</p><p><b>RESULTS</b>A total of 218 elective PCI patients were randomized into a bivalirudin group (n = 110) and heparin group (n = 108). Except for two patients needing additional dosing in the heparin group, the ACT values of all other patients in both groups were longer than 225 seconds at 5 minutes after the first intravenous bolus. Procedural success rates were respectively 100.0% and 98.2% in the bivalirudin group and heparin group (P > 0.05). Survival rates without major adverse cardiac events at 30 days after PCI were 100.0% in the bivalirudin group and 98.2% in the heparin group (P > 0.05). Mild bleeding rates were 0.9% and 6.9% (P < 0.05) at 24 hours, and 1.9% and 8.8% (P < 0.05) at 30 days after PCI in the bivalirudin group and heparin group respectively. There was one severe gastrointestinal bleeding case in the heparin group.</p><p><b>CONCLUSIONS</b>Domestic bivalirudin is an effective and safe anticoagulant during elective PCI procedures. The efficacy is not inferior to heparin, but the safety is superior to heparin.</p>

Reverse 201Tl myocardial redistribution induced by coronary artery spasm / 中华核医学杂志

Objective To investigate the mechanism of reverse redistribution (RR) on dipyridamole 201Tl myocardial perfusion studies in the patients with coronary artery spasm. Methods Twenty-six patients with coronary artery spasm and presented as RR on dipyridamole 201Tl myocardial perfusion studies were enlisted as RR group, while other 16 patients with no coronary artery stenosis nor RR were enlisted as control group. Dipyridamole test was repeated during coronary angiography. Corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC) and TIMI myocardial perfusion grade (TMPG) were measured at RR related and non-RR related coronary arteries before and after dipyridamole infusion respectively.All of the data were analyzed by Student's t-test orχ2-test and correlation analysis. Results Coronary artery angiography showed slower blood flow and lower myocardial perfusion in RR related vessels when compared with non-RR related vessels in RR group, but there was no significant difference among the main coronary arteries in control group. The perfusion defects of RR area at rest were positively related to slowerblood velocity at corresponding coronary arteries ( r = 0.79, t = 10.18, P ＜ 0.001 ). In RR related vessels,CTFC were (36 ±6) frames and (26 ±7) frames (t =4.15, P ＜0.01 ), while TMPG were (2.02 ±0.39)grades and (2.92 ± 0.12) grades ( t = 2.25, P ＜ 0.05 ) before and after dipyridamole infusion, respectively.In non-RR related vessels, CTFC were (29 ±7) frames and (25 ±5) frames (t =2.31, P ＜0.05), while TMPG were (2.56 ± 0.31 ) grades and (2.96 ± 0.06) grades ( t = 2.17, P ＜ 0.05 ) before and after dipyridamole infusion, respectively. However, there were no significant changes of CTFC and TMPG before and after dipyridamole infusion in control group ( t = 0.932, 0.867, respectively, both P ＞ 0.05 ). Conclusion RR is related to the decreased blood flow and myocardial perfusion induced by coronary artery spasm at rest,which may be improved by stress test such as intravenous dipyridamole infusion.

Effects of oxygen and calcium on the expression of wild-type and mutated hypoxia-inducible factor-1alpha eukaryotic vectors in HEK293 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effects of oxygen and calcium on the expression of eukaryotic vectors harboring wild-type or mutated hypoxia-inducible factor-1alpha (HIF-11alpha) in HEK293 cells.</p><p><b>METHODS</b>HEK293 cells were transiently transfected with pcDNA3.1+/HIF-11alpha, pcDNA3.1+/HIF-11alpha-564Ala and pcDNA3.1+/HIF-11alpha-564Ala-803Ala via lipofectin. Western blotting were used to detect HIF-11alpha protein after normoxic or hypoxic exposure of the transfected HEK293 cells in the presence or absence of Ca(2+). The levels of vascular endothelial growth factor (VEGF) mRNA in the transfected cells in normoxic condition was detected using RT-PCR.</p><p><b>RESULTS</b>The levels of HIF-11alpha protein and VEGF mRNA increased in HEK293 cells transfected with the vectors harboring mutated HIF-11alpha, but not in the cells transfected with wild-type HIF-11alpha vectors in normoxia. Hypoxia increased the levels of HIF-11alpha protein in the cells transfected with wild-type HIF-11alpha vectors, which was inhibited by the application of Ca(2+). Ca(2+) showed no inhibitory effect on HIF-11alpha levels in HEK293 cells transfected with the vectors containing mutated HIF-11alpha.</p><p><b>CONCLUSION</b>The protein products of pcDNA3.1+/HIF-11alpha-564Ala and pcDNA3.1+/HIF-11alpha- 564Ala-803Ala in HEK293 cells enhance the cell tolerance to oxygen and protease.</p>

Expression of B7-related protein-1 on human coronary artery endothelial cells and its clinical significance / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effect of oxidized low density lipoprotein (ox-LDL) on the expression of B7-related protein-1 (B7RP-1) on human coronary artery endothelial cells (HCAECs).</p><p><b>METHODS</b>HCAECs were incubated in the presence of 100 mg/L ox-LDL for 24 h, and B7RP-1 expression levels were determined using fluorescence reverse transcription PCR (RT-PCR) and Western blotting.</p><p><b>RESULTS</b>B7RP-1 expression was detected HCAECs, with spots of fluorescence signals distributing on the cell membrane as observed under fluorescence microscope. RT-PCR with B7RP-1 specific primers yielded products of expected size (496 bp). Western blotting identified B7RP-1 expression in the HCAECs as a cell-associated protein with an apparent molecular mass of 70,000. Treatment of the cells with ox-LDL significantly increased B7RP-1 expression at both the mRNA and protein levels (P<0.05).</p><p><b>CONCLUSION</b>B7RP-1 is expressed on the membrane of HCAECs. ox-LDL can promote up-regulate the expression of B7RP-1, which might be one of the immunopathogenesis of atherosclerosis.</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>

Effect of porcine relaxin on NO production of human microvascular endothelial cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe effect of porcine relaxin(pRLX) on NO production of human microvascular endothelial cells(HMVECs) and discuss its possible mechanism.</p><p><b>METHODS</b>iNOS and cNOS expression of HMVECs with or without pRLX were detected using western blotting. NO production of HMVECs with pRLX at different concentration or different time were determined by method of Griess. NO production of pRLX of HMVECs plus Non-selective NOS inhibitor NG-monomethyl-L-arginine(L-NMMA), selective iNOS inhibitor aminoguanidine(AG) or nuclear factors-kappaB (NF-kappaB) inhibitor pyrrolidine dithiocarbamate(PDTC) were also analysed.</p><p><b>RESULTS</b>pRLX promoted iNOS protein expression of HMVECs, but not cNOS protein expression. NO production of HMVECs was promoted by pRLX on concentration-dependent pattern instead of time-dependent one. AG, L-NMMA and PDTC were showed to block the effect of pRLX on NO production of HMVECs.</p><p><b>CONCLUSION</b>pRLX promote iNOS expression and NO production of HMVECs.</p>

Comparison of plasma low-density lipoprotein and oxidized low-density lipoprotein levels with coronary lesion severities in patients with coronary artery disease / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the relationship between plasma low-density lipoprotein (LDL) and oxidized low-density lipoprotein (ox-LDL) levels and the severity of coronary atherosclerosis.</p><p><b>METHODS</b>Fasting plasma ox-LDL was measured by enzyme-linked immunosorbent assay and plasma LDL was measured by biochemical autoanalyser in 31 patients with coronary artery spasm (CAS group, chest pain with positive acetylcholine provocation test but without significant coronary artery stenosis), 35 patients with stable angina pectoris (SAP group) and 24 healthy persons (control group).</p><p><b>RESULTS</b>Plasma LDL levels were similar between CAS and SAP groups but significantly higher than that in control group. Plasma ox-LDL levels significantly increased in proportion to coronary lesion severities [SAP (575 +/- 219 microg/L) > CAS (299 +/- 117 microg/L) > control (218 +/- 35 microg/L)]. In SAP group, plasma ox-LDL level was also significantly higher in multi-vessel disease group than that in single-vessel disease group (672 +/- 92 vs. 462 +/- 72 microg/L, P < 0.05).</p><p><b>CONCLUSION</b>Plasma ox-LDL but not LDL level is significantly correlated to the severity of coronary atherosclerosis and should therefore be the focused therapy target in patients with coronary artery disease.</p>

Clinical features of patients with atypical coronary artery spasm / 中华心血管病杂志

<p><b>OBJECTIVE</b>This study is aimed to compare the clinical characteristics of patients with typical and atypical coronary artery spasm.</p><p><b>METHODS</b>Out of 64 patients with chest pain at rest and without significant coronary artery stenosis, coronary artery spasm was provoked by intracoronary injection of acetylcholine in 46 patients, including 12 with ST segment elevation (typical coronary artery spasm group) and 34 without ST segment elevation (atypical coronary artery spasm group). The demographic data, coronary angiographic findings, treadmill electrocardiogram, dipyridamole and rest thallium-201 myocardial perfusion computed tomography, and the follow-up clinical data of the two groups were compared.</p><p><b>RESULTS</b>The patients with typical coronary artery spasm were younger (47 +/- 6 vs. 58 +/- 12, P < 0.05) than patients with atypical coronary artery spasm group. Hyperlipidemia were more common in atypical coronary artery spasm group (74% vs. 33%, P < 0.05) and myocardial bridging was more common in patients with typical coronary artery spasm group (67% vs. 32%, P < 0.01). Focal coronary spasm during acetylcholine provocation was seen in 92% patients with typical coronary spasm and in 32% patients with a atypical coronary artery spasm (P < 0.01) while diffuse coronary spasm was seen in 8% patients with typical coronary spasm and in 68% patients with a atypical coronary artery spasm (P < 0.01). All patients with coronary artery spasm were treated with aspirin, calcium channel blockers, long-acting nitroglycerine, with or without lipid-lowering drugs, 2 patients with typical coronary spasm and 4 patients with atypical coronary spasm were rehospitalized due to chest pain and rest of the patients remained free of chest pain during the median follow-up period of 18 +/- 14 months.</p><p><b>CONCLUSION</b>Atypical coronary artery spasm is common in patients with rest angina and diffuse coronary microvascular spasm might be the cause of chest pain in these patients.</p>