硫化氢对大鼠心房肌细胞三磷酸腺苷敏感性钾通道电流的影响

目的观察内源性及外源性硫化氢(H2S)对大鼠离体心房肌细胞三磷酸腺苷(ATP)敏感性钾通道(KATP)外向电流的影响,以探讨H2S对心房肌细胞的作用。方法对大鼠离体心脏采用胶原酶酶解法得到单个心房肌细胞,采用膜片钳全细胞技术记录H2S生成酶——胱硫醚-γ-裂解酶的不可逆抑制剂DL-propargylglycine(PPG)用药前、用药后5,10,15,20,25 min及不同浓度外源性H2S的供体硫氢化钠(NaHS)干预前后的KATP电流。结果经200μmol/L PPG干预后KATP峰电流密度(+70 mV)显著减小(6.906 6±1.902 9 pA/pF vs 3.924 4±0.988 5 pA/pF,P<0.01),且具有时间依赖性。经9.375,18.75,37.5,75,150μmol/L NaHS干预后KATP峰电流密度呈浓度依赖性增大,至150μmol/L时峰电流密度明显增大(6.5974±1.1527 pA/pF vs 10.463 1±2.329 7 pA/pF,P<0.01)。结论内源性及外源性H2S均可以开放大鼠离体心房肌KATP通道,使KATP电流增加。     

硫化氢对心房颤动相关离子通道的影响及机制

心房颤动（房颤）的发病机制与离子通道重构密切相关。近年来新发现的心血管系统作用活跃的气体信号分子硫化氢对多个离子通道均有作用。该文综述硫化氢对房颤发病中钠离子通道、钾离子通道、钙离子通道等多个离子通道的作用及其机制,为其将来成为房颤治疗靶点提供理论依据。     

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.     

ACC/AHA不稳定型心绞痛和非ST段抬高心肌梗死治疗指南(2007年修订版)解读(1)

2007年8月,ACC/AHA对2002年以来的临床试验进行了分析,将2002年的不稳定型心绞痛/非ST段抬高心肌梗死(UA/NSTEMI)治疗指南(2002年指南)进行了修订,颁布了新的指南(2007年指南).指南中插入了更多张流程图片,内容涉及多个方面,甚至有如图1所示的医师如何指导患者自我处理的流程图.再者,该指南依然强调的是面对患者要考虑到两方面问题,即该患者有否可能是冠脉闭塞导致的UA/NSTEMI;临床可能会出现哪些负面的情况.     

心房颤动诊治的现状与展望

据我国2013年中国心血管病报告提出我国房颤30~85岁人群中总患病率约为0.77%[1]。随着年龄增长房颤的发病率不断增加,在65岁以上的老年人当中发生率>5%,75岁以上人群可达10%。房颤的最大危害是导致心功能下降[2]和心房内血栓形成,并且血栓脱落容易造成脑栓塞[3]。根据Framingham研究,非瓣膜病性房颤患者脑卒中发生率是正常人的5.6倍,瓣膜病房颤脑卒中发生率是正     

ACC/AHA/HRS 2008年心律失常装置植入治疗指南解读(2)

2008年ACC/AHA/HRS心律失常的植入装置治疗指南,内容较以往指南变化较大.前面我们已经阐述了在窦房结功能异常起搏治疗建议、成人获得性房室传导阻滞起搏治疗建议、慢性双分支传导阻滞起搏治疗建议和急性心肌梗死房室阻滞起搏治疗建议等几方面新指南的特点.下面将就其他内容的特点进行阐述.