全球心肌梗死统一定义指南解读(2)

2007年,全球统一的心肌梗死定义出台.上次解读中,我们就新定义的内容进行了总结,并且分析了部分新定义的特征.本文将继续分析2007年全球统一心肌梗死定义的特征和与以往定义的异同.     

硫化氢对离体大鼠心室肌细胞ATP依赖的钾通道外向电流的影响

Objective To investigate the effects of endogenous and exogenous hydrogen sulfide (H2S) on the KATP current in isolated rat ventricular myoeytes. Methods Ventrieular myoeytes were isolated from rat heart by modified Langendoff perfusion with collagenase. KATP current of single rat ventricular myocytes was recorded by whole-cell patch-clamp technique. Results The density of KATP current was significantly reduced by 200 μmol/L DL-propargylglyeine (PPG, an irreversible inhibitor of the H2S) [(5.3258±0.7556) pA/pF vs. (3.7856±0.4312) pA/pF, P ＜ 0.01] in a time-dependent way. The density of KATP current could be significantly increased by NariS(a H2S donor, 9.375, 18.75, 37.5,75, 150 μmol/L) in a concentration-dependent manner [(6.6310±0.6092) pA/pF vs. (9.0949±1.0259)pA/pF at 150 μmol/L, P ＜ 0.01]. Conclusion Both endogenous and exogenous H2S could open KATP channels and enhance the KATP current in rat ventricular myocytes.     

氧化低密度脂蛋白对人红细胞左旋精氨酸转运的影响

目的 :观察氧化低密度脂蛋白对健康人红细胞左旋精氨酸 (L arg)转运的影响。方法 :用低密度脂蛋白和氧化低密度脂蛋白分别孵育正常人红细胞后将细胞分为对照组、低密度脂蛋白组和氧化低密度脂蛋白组 ,以3 H标记的L arg(3 H L arg)来测定红细胞的L arg转运。结果 :低密度脂蛋白对红细胞L arg转运无明显影响 (P >0 0 5 )。氧化低密度脂蛋白抑制红细胞L arg转运 :氧化低密度脂蛋白组氧化低密度脂蛋白 2 5、5 0、10 0mg/L 3个浓度总摄入的最大转运速率 (Vmax)值分别较对照组降低 3 3 %、2 7%、3 0 % (P均 <0 0 5 ) ,亲和力明显减小 (米氏常数值增大 ,P <0 0 5 ) ,均有显著性差异 ,未见明显的浓度—效应依赖关系 ;与对照组相比 ,氧化低密度脂蛋白组氧化低密度脂蛋白 2 5、5 0、10 0mg/L 3个浓度y +载体介导的L arg转运的最大转运速率值明显降低 ,分别降低 43 %、48%、45 % (P均 <0 0 5 ) ,均有显著性差异 ,亲和力明显减小 (米氏常数值增大 ) ;与对照组相比 ,氧化低密度脂蛋白组通过y +L载体介导的L arg转运 (最大转运速率值及米氏常数值 )均无明显改变 (P>0 0 5 )。结论 :低密度脂蛋白氧化成氧化低密度脂蛋白后抑制红细胞L arg的跨膜转运 ,推测氧化低密度脂蛋白是高脂血症患者红细胞L arg/一氧化氮途径     

硫化氢对离体大鼠心室肌细胞ATP依赖的钾通道外向电流的影响

Objective To investigate the effects of endogenous and exogenous hydrogen sulfide (H2S) on the KATP current in isolated rat ventricular myoeytes. Methods Ventrieular myoeytes were isolated from rat heart by modified Langendoff perfusion with collagenase. KATP current of single rat ventricular myocytes was recorded by whole-cell patch-clamp technique. Results The density of KATP current was significantly reduced by 200 μmol/L DL-propargylglyeine (PPG, an irreversible inhibitor of the H2S) [(5.3258±0.7556) pA/pF vs. (3.7856±0.4312) pA/pF, P ＜ 0.01] in a time-dependent way. The density of KATP current could be significantly increased by NariS(a H2S donor, 9.375, 18.75, 37.5,75, 150 μmol/L) in a concentration-dependent manner [(6.6310±0.6092) pA/pF vs. (9.0949±1.0259)pA/pF at 150 μmol/L, P ＜ 0.01]. Conclusion Both endogenous and exogenous H2S could open KATP channels and enhance the KATP current in rat ventricular myocytes.     

染色体9p21上rs10757278单核苷酸多态性与汉族人心肌梗死的相关性分析

目的研究染色体9p21上rs10757278位点单棱苷酸多态性（sNP）与中国汉族人群心肌梗死患病的相关性。方法选取432倒初发心肌梗死患者（MI组）及430例同期住院的外科对照患者。采用PCR—SNPStream技术对rs10757278位点进行多态性分型。并对分型蛄泰进行统计学分析。结果在MI组,rs10757278位点的GG、AG基因型分布频率高于对照姐,G等位基因分布频率也高于对照组（P〈0．01）。经校正混杂因素的影响后,我们发现rs10757278位点G等位基因的单个拷贝使MI发生的风险分别提高了33％（P〈0．05）。结论rs10757278是汉族人MI发生的易感位点。     

中心静脉压测量在房颤射频消融术中的应用

目的:探索中心静脉压测量在房颤射频消融术中应用的价值,尤其对于在合并心功能不全的房颤患者消融中的意义。方法:入选39例导管消融的房颤患者,平均年龄(64.4±12.6)岁。阵发性房颤24例,持续性、永久性房颤15例。心功能NYHAⅠ级17例,Ⅱ级18例,Ⅲ级4例。左室射血分数51%～77%。分别测量消融术前、术后即刻中心静脉压。结果:患者术后平均中心静脉压(12.9±4.6)cmH2O较术前平均中心静脉压(9.1±1.8)cmH2O有明显升高(P=0.000);手术前后的变化值(△CVP)在心功能Ⅲ级组(6.3±5.3)cmH2O显著高于Ⅰ级组(3.5±3.0)cmH2O和Ⅱ级组(2.3±3.2)cmH2O(P<0.05);术后中心静脉压与手术时间、放电时间的相关系数分别为0.797(P=0.010),0.675(P=0.046);消融术前后中心静脉压变化值与手术时间、放电时间的相关系数分别为0.904(P=0.001),0.806(P=0.009)。术后出现心衰症状或肺部啰音的患者,术后中心静脉压以及中心静脉变化值均明显高于无症状组和无啰音组(均P<0.05)。结论:房颤合并心功能不全患者进行射频消融术时,中心静脉压可成为术中监测的重要临床内容,不仅方法简单实用,更可以提高术中的安全性。     

20年间美国髋关节置换术盛衰变化

每年美国有28万成年人进行全髋关节置换术。根据对国民保险数据（医疗保险）的一项统计研究表明，与1991年的相比，老龄化在加剧，同时肥胖、糖尿病、心力衰竭、肾功能衰竭等疾病的发生率在增加。然而，这些人的死亡率仍在下降，特别是初次手术后。到2008年，外科手术后1个月死亡风险仅为0．4％（而1991年这一数据为0．7％，P〈0．001）。     

食管造影及温度监测指导环肺静脉消融治疗心房颤动

Objective Because of the severe consequences of an atrial esophageal fistula,it is vital to avoid this complication. The most safe way is to avoid ablating the segment of esophagus behind left atrium (LA). What we do is to image the relationship of esophagus to posterior LA wall and real-time esophageal tem-perature monitoring to ablate the posterior LA wall. Methods Sixty-four patients with paroxysmal atrial fibrilla-tion (PAF) were enrolled to pulmonary veins (PV) isolation. Swallowing a radiocontrast agent at the same time when imaging of LA to observe the relationship of esophagus to posterior LA wall and according to the different relationship between the segment of esophagus behind LA and PV, the esophagus were divided into type Ⅰ , type Ⅱ and type Ⅲ. A esophageal temperature probe was inserted and advanced into the esophagus directly posterior to the LA. Three steps ablation strategy and real-time esophageal temperature monitoring were applied to guide the PV isolation. The procedure was interrupted when the esophageal temperature was 39℃ until] the tempera-ture renormalized and ended when PV were isolated. Results There were 48 type ⅠI , 11 type Ⅱ and 5 type Ⅲ esophagus in the 64 patients. After three steps ablation,all PV isolations were completed. Only 18.8% of the patients needed to ablate the posterior LA close to the esophagus. Conclusion Only one PV ostiolum close to the posterior LA wall in most PAF patients and many of them can achieve complete PV isolation without ablating the posterior LA close to esophagus which could minimize the risk of esophageal injury dramatically.     

亚临床甲状腺功能减退与甲状腺功能减退患者心脏结构及功能的改变

目的 观察亚临床甲状腺功能减退（SCH）和甲状腺功能减退（甲减）患者的超声心动图,分析其心脏结构与功能的改变。方法 选取2011年3月至2017年3月北京朝阳医院收治的58例SCH患者为SCH组,21例甲减患者为甲减组,选择同期甲状腺功能正常的健康体检者65例为对照组进行回顾性研究。比较3组对象超声心动图参数如左室舒张末期内径（LVEDD）、左室收缩末期内径（LVESD）、左室射血分数、主动脉窦内径等的变化,并分析甲状腺功能状态对3组研究对象心脏结构与功能的影响。结果 对照组、SCH组及甲减组患者的LVEDD分别为（47.69±4.13）、（45.33±4.45）和（42.81±4.26）mm,3组差异有统计学意义（P<0.05）。对照组、SCH组及甲减组患者的LVESD分别为（29.69±3.34）、（27.45±4.16）和（26.48±3.89）mm,3组差异有统计学意义（P<0.05）。结论 SCH患者与甲状腺功能减退患者的LVEDD和LVESD减小,左心室功能降低。     

ACC／AHA／HRS2008年心律失常装置植入治疗指南解读（1）

2008年5～6月，ACC／AHA／HRS共同拟定了心律失常的植入装置治疗指南，此指南是在2002年指南基础之上的改进与提高。无论在形式上还是内容上都有较大的变化。