Effects of Percutaneous Coronary Intervention on Serum Angiopoietin-2 in Patients with Coronary Heart Disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Angiopoietin-2 (Ang-2) plays a crucial role in hypoxia-induced angiogenesis and is expressed only in sites of vascular remodeling. Ang-2 expression can be regulated by hypoxia inducible factors and other regulators with exposure to hypoxia. The objective of this study was to investigate the influence of percutaneous coronary intervention (PCI) on serum Ang-2 concentrations, and analyze the correlation between serum Ang-2 and the severity of coronary artery stenosis in patients with coronary heart disease (CHD).</p><p><b>METHODS</b>Sixty-four patients with CHD were selected as the study group, each undergone PCI. Thirty-two healthy subjects were selected as the control group. Pre-PCI and post-PCI serum Ang-2 were measured by enzyme-linked immunosorbent assay. The severity of coronary artery stenosis was evaluated using angiographic Gensini scores, and the coronary collateral vessels were scored according to Rentrop's classification.</p><p><b>RESULTS</b>Concentrations of pre-PCI serum Ang-2 in the study group were significantly higher than those in the control group (4625.06 ± 1838.06 vs. 1945.74 ± 1588.17 pg/ml, P < 0.01); however, concentrations of post-PCI serum Ang-2 were significantly lower than those of pre-PCI (3042.63 ± 1845.33 pg/ml vs. 4625.06 ± 1838.06 pg/ml, P < 0.01). Concentrations of pre-PCI serum Ang-2 were significantly correlated with Gensini scores (r = 0.488, P < 0.01); however, the decrease in serum Ang-2 after PCI was not correlated with Gensini scores, coronary collateral vessel grading, or left ventricular ejection fraction.</p><p><b>CONCLUSIONS</b>Serum Ang-2 concentrations significantly increased in patients with CHD, and PCI treatment significantly decreased these concentrations. Serum Ang-2 concentrations, but not the decrease in serum Ang-2 concentrations, were significantly correlated with the severity of coronary artery stenosis. These results suggested that Ang-2 may be a biomarker of myocardial ischemia and vessel remodeling.</p>

Features and variations of a radial artery approach in southern Chinese populations and their clinical significance in percutaneous coronary intervention / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>More and more percutaneous coronary intervention were done from radial artery approach. But the great limitation of radial artery approach and main failure cause of transradial coronary intervention is smaller size and more variations of a radial artery approach. The aim of the study is to explore the features and variations of a radial artery approach in southern Chinese populations and their clinical significance in percutaneous coronary intervention.</p><p><b>METHODS</b>A total of 1400 patients who underwent scheduled first time transradial coronary angiography between July 2007 and September 2010 were enrolled. Radial arteriography was performed in all patients to detect the anatomical variations of this vessel. All patients' radial and ulnar artery inner diameters were measured using a computer assisted quantification method. A detailed patient history was recorded. Multivariate Logistic regression analysis was performed to evaluate the predictive value of variables (including age, gender, ethnicity, height, weight, body mass index, smoking, diabetes, hypertension and dyslipidemia) in arterial tortuosities and variations of this vessel.</p><p><b>RESULTS</b>In southern Chinese populations, there were no significant differences in the diameters of the forearm arteries: the mean radial artery inner diameter was (3.04 ± 0.43) mm in ethnic Han Chinese and (3.05 ± 0.42) mm in ethnic Zhuang Chinese, P > 0.05), the mean ulnar artery inner diameter was (3.03 ± 0.38) mm in Han Chinese and (3.05 ± 0.36) mm in Zhuang Chinese, P > 0.05). It was estimated that the inner diameter of the radial artery was not smaller than a 6F Cordis sheath in 86.1% of male patients and in 57.0% of female patients, and not smaller than a 7F Cordis sheath in 59.3% of male patients and 24.9% of female patients. The factors found to positively affect the size of the radial artery were sex (bj = 0.309, P < 0.01), weight (bj = 0.103, P < 0.01), and diabetes mellitus (bj = -0.088, P < 0.01) was found to negatively affect radial artery size. Arterial tortuosities occurred in 12.1% of patients and arterial variations in 4.1%. The incidence of tortuosities and variations included radial artery tortuosity (3.6%), high origin of radial artery (1.7%), radial artery loop (0.6%), double radial artery (0.1%), brachial artery tortuosity (0.4%), double brachial artery (0.1%), subclavian artery tortuosity (5.4%), small subclavian artery (0.4%), right retro-esophageal subclavian artery (0.6%), brachiocephalic trunk tortuosity (2.8%), small brachiocephalic artery (0.1%), and brachiocephalic artery anomaly (0.4%). For people in Guangxi province, tortuosities of the subclavian artery and radial artery are the most common among the vascular tortuosities of the radial artery approach. The overall rate of transradial procedural success was 96.1%. Procedural failure was more common in patients with anomalous radial artery approach than in patients with normal radial artery approach (22.8% vs. 1.8%, P = 0.000). According to multivariate Logistic regression analysis, age (OR = 2.695, 95%CI 2.232 - 3.253, P = 0.000), female gender (OR = 5.127, 95%CI 3.000 - 8.762, P = 0.000), height (OR = 0.612, 95%CI 0.465 - 0.807, P = 0.000), body mass index (OR = 2.377, 95%CI 1.834 - 3.082, P = 0.000), hypertension (OR = 1.668, 95%CI 1.132 - 2.458, P = 0.010), hyperlipidemia (OR = 1.273, 95%CI 1.425 - 2.049, P = 0.034) and smoking (OR = 5.750, 95%CI 3.636 - 9.093, P = 0.000), were independently associated with arterial tortuosities of the radial artery approach. Female gender was independently associated with arterial variations of the radial artery approach (OR = 3.613, 95%CI 3.208 - 7.826, P = 0.000).</p><p><b>CONCLUSIONS</b>The diameters of the radial and ulnar arteries between the Han people and the Zhuang people in southern Chinese populations are similar. In a transradial operation, the most southern Chinese populations, the use of a 6F sheath and guiding catheter is safe, and using a 7F sheath and guiding catheter is feasible in some selected patients. Radial arterial tortuosities and variations in southern Chinese populations are relatively common and are a significant cause of the failure of transradial coronary procedure. Old age, female gender, short stature, high body mass index, hypertension, hyperlipidemia and smoking, were independently associated with an increased risk of arterial tortuosity. In addition, female gender was an independent predictor of arterial variations.</p>

The effect of mitochondrial oxidative stress and the expression of Bcl-2 and Bax proteins on cardiomyocyte apoptosis during hypoxia postconditioning / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate mitochondrial oxidative stress on cardiomyocyte apoptosis and the expression of Bcl-2 and Bax proteins in cardiac sarcolemma and mitochondria after application of hypoxia postconditioning and free radical scavengers.</p><p><b>METHODS</b>Primary cultured neonatal rat cardiomyocytes were exposed to 3 h hypoxia (H) followed by (1) 6 h of reoxygenation (R) (H/R), (2) 3 intermittent cycles of 5 min H and R before 6 h of R (PC), (3) application of superoxide dismutase (SOD) before PC (SOD+PC), (4) application of catalase (CAT) before PC (CAT+PC), and (5) application of SOD plus CAT before PC (SOD+CAT+PC). Cardiac sarcolemma and mitochondria were isolated by differential centrifugation. Mitochondrial reactive oxygen species (ROS) was detected with fluorescent probes (DCFH-DA) and cardiomyocyte apoptosis was detected with flow cytometry. The expressions of Bcl-2 and Bax proteins in cardiac sarcolemma and mitochondria were measured by Western blot.</p><p><b>RESULTS</b>Mitochondrial ROS reduced significantly in PC, SOD+PC, CAT+PC and especially in SOD+CAT+PC groups (all P<0.01). The number of apoptotic cardiomyocytes reduced significantly in PC, SOD+PC and CAT+PC (all P<0.01) but not in SOD+CAT+PC groups. Bcl-2 levels increased while Bax levels decreased in cardiac sarcolemma and mitochondria in PC, SOD+PC and CAT+PC groups (all P<0.01), Bcl-2 levels decreased and Bax levels increased in H/R and PC+SOD+CAT groups (all P<0.01).</p><p><b>CONCLUSIONS</b>PC attenuated H/R induced ROS and cardiomyocyte apoptosis, which might be mediated by upregulating the expression of Bcl-2 and downregulating the Bax in mitochondria and sarcolemma; SOD or CAT alone did not but SOD plus CAT attenuate the anti-apoptotic effect of hypoxia postconditioning; mitochondrial ROS thus plays an important role in PC's cardioprotection.</p>

A meta-analysis on efficacy of anti-platelet agents and anticoagulants for preventing stroke in patients with nonvalvular atrial fibrillation / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy and security of anti-platelet and anticoagulant therapy on prevention of ischemic stroke in patients with nonvalvular atrial fibrillation (NAF).</p><p><b>METHODS</b>We searched PubMed, EMbase, CENTREN and its affiliated clinical trial registration data center, CBMdisc, VIP, and CNKI databases from establishment to Dec 2009 to identify randomized controlled trials (RCTs) covering the use of anti-platelet agents and anticoagulants for patients with NAF. Meta-analysis was performed by using RevMan 5.0 software after the strict evaluation of the methodological quality of the included RCTs.</p><p><b>RESULTS</b>Fourteen RCTs involving 15 880 patients were include. Compared with placebo or no use of anti-platelet drugs, antiplatelet therapy didn't reduce ischemic stroke (RR = 0.83, 95%CI 0.68 to 1.00, P = 0.05), systemic emboli (RR = 0.71, 95%CI 0.34 to 1.51, P = 0.38) and all-cause mortality (RR = 0.88, 95%CI 0.73 to 1.07, P = 0.21) while significantly increased the major bleeding (RR = 2.88, 95%CI 1.21 to 6.86, P = 0.02) in patients with NAF, intracranial hemorrhage was not affected by antiplatelet therapy in patients with atrial fibrillation (RR = 3.25, 95%CI 0.84 to 12.62, P = 0.09). Compared with anti-platelet therapy, anticoagulant therapy significantly reduced the incidence of ischemic stroke (RR = 1.84, 95%CI 1.48 to 2.28, P < 0.01) and systemic emboli (RR = 1.94, 95%CI 1.24 to 3.03, P = 0.004) but significantly increased the incidence of intracranial hemorrhage (RR = 0.49, 95%CI 0.31 to 0.78, P = 0.003), did not affect all-cause mortality (RR = 1.06, 95%CI 0.90 to 1.23, P = 0.50) and the incidence of major bleeding (RR = 0.95, 95%CI 0.76 to 1.19, P = 0.66) in NAF patients.</p><p><b>CONCLUSIONS</b>Compared with the placebo and no use of anti-platelet drugs, anti-platelet therapy didn't reduce ischemic stroke and systemic emboli but increased the risk of major bleeding in NAF patients. Compared with anti-platelet therapy, anticoagulant therapy significantly reduced the ischemic stroke and systemic emboli without increasing the risk of major bleeding, but significantly increased the incidence of intracranial hemorrhage in NAF patients. Since the study included RCTs with limited and less uniform outcome endpoints, the conclusions should be verified with RCTs with more uniform endpoints and longer follow-up time.</p>

Mitochondrial connexin43 and postconditioning protection in rabbits underwent myocardial ischemia/reperfusion injury / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the roles of mitochondrial connexin43 (Cx43) and mitochondrial ATP sensitive potassium channe1 (mitoK(ATP)+) in the postconditioning protection for rabbits underwent myocardial ischemia/reperfusion injury.</p><p><b>METHODS</b>In anesthetized open-chest rabbits, the left anterior descending artery (LAD) was occluded for 30 min and reperfused for 4 h and randomly divided into four groups (n = 16 each): sham operation group (Sham), ischemic reperfusion group (IR), ischemic postconditioning group (PC) and PC plus 5-HD, a specific mitoK(ATP)+ inhibitor (PC + 5-HD). Rabbits were sacrificed post 4 h reperfusion. Heart rate and the mean arterial pressure were recorded and plasma CK-MB and cTnI activity were measured at baseline, at the end of ischemia, and after 2 h and 4 h of reperfusion, respectively. Myocardial infarct size was determined and mitochondria structure was observed under electron microscope at the end of the experiment. Mitochondria were isolated and the protein content of the mitochondrial Cx43 was determined by Western blot.</p><p><b>RESULTS</b>Plasma CK-MB, cTnI activity and myocardial infarct size were significantly reduced in PC [(19.1 +/- 3.9)%] group compared to IR [(35.7 +/- 5.8)%] and PC + 5HD [(34.2 +/- 3.9)%] groups (all P < 0.01). Degree of mitochondria damage was significantly reduced in PC group compared to IR and PC + 5HD groups (all P < 0.01). The mitochondria Cx43 content was significantly decreased in IR group and PC + 5-HD group compared to sham group (all P < 0.05) and restored in PC group.</p><p><b>CONCLUSION</b>Ischemic postconditioning protected the heart from I/R injury by improving mitochondrial ultrastructure and by attenuating I/R induced decrease of mitochondria Cx43 expression. The protective effects of postconditioning was partly mediated by activating mitoK(ATP)+ pathway.</p>

The association of single nucleotide polymorphism of slow delayed rectifier K+ channel genes with atrial fibrillation in Han nationality Chinese / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the association between atrial fibrillation and the single nucleotide polymorphism (SNP) of slow delayed rectifier K(+) channel (I(Ks)) genes in Han nationality Chinese.</p><p><b>METHODS</b>Three hundred and eighty of Han nationality Chinese (142 atrial fibrillation, 120 in-hospital and 118 out-hospital control) were enrolled in this study. Asian specific non-synonymous SNPs of KCNQ1 P448R, KCNQ1 R519H, KCNQ1 G643S, KCNE1 G38S and KCNE1 D85N were genotyped by restriction fragment length polymorphism analysis. A newly cloned KCNE4 gene was also screened for any possible SNP.</p><p><b>RESULTS</b>The minor allele frequency of KCNQ1 P448R, KCNQ1 R519H, KCNQ1 G643S, KCNE1 G38S and KCNE1 D85N in out-hospital subjects was 0.079, 0, 0.042, 0.317 and 0.004, respectively. None of these SNPs was relationed with any atrial fibrillation phenotype. A KCNE4 E145D was discovered and proven statistically to relation significantly to atrial fibrillation by logistic regression analysis (OR = 1.66, P = 0.044). The minor allele frequency of KCNE4 E145D was as high as 0.271 in out-hospital subjects.</p><p><b>CONCLUSIONS</b>None of the SNPs of KCNQ1 P448R, KCNQ1 R519H, KCNQ1 G643S, KCNE1 G38S and KCNE1 D85N was associated with atrial fibrillation phenotype, but KCNE4 E145D may relation to atrial fibrillation. The effect of KCNE4 E145D variation on the function of I(Ks) channel is to be determined.</p>