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1.
目的本研究拟探讨不同类型二尖瓣病变患者心房颤动(atrial fibrillation,AF)与心房结构重构之间关系。方法 24例需入院手术治疗的单纯中-重度二尖瓣膜病变患者纳入本研究。在术中体外循环转流前结扎左心耳并切取部分左心耳组织。通过彩超检查、电镜检查及免疫组化的方法评价左房心肌组织结构重构。结果在二尖瓣病变患者中,左房与AF持续时间均呈直线相关关系(r=0.769,P=0.000)。在同伴有AF患者中,不同类型二尖瓣瓣膜病变电镜结果不同。在同伴有AF患者中,不同类型二尖瓣病变有着不同的程度Ⅰ型胶原和Ⅲ型胶原增长。和二尖瓣返流组相比较,在二尖瓣狭窄组中,Ⅰ型胶原和Ⅲ型胶原都增长,但仅有Ⅰ型胶原增长明显(P=0.043)。在二尖瓣病变患者中,Ⅰ型胶原和Ⅲ型胶原含量与AF持续时间呈直线相关关系,尤Ⅰ型胶原与AF相关关系更明显(r=0.862,P=0.000)。结论在伴有AF患者,不同类型二尖瓣病变患者有着不同程度的心房结构重构。二尖瓣狭窄患者心房肌组织结构重构程度高于二尖瓣返流心房肌组织结构重构。  相似文献   

2.
目的研究普罗布考对快速起搏犬心房颤动(AF)发生及心房结构的影响,并探讨其机制。方法 21只杂种犬被随机分为假手术组(n=7)、起搏组(n=7)和普罗布考组(n=7)。起搏组和普罗布考组犬行心房400次/分快速起搏6周。普罗布考组于起搏前1周给予普罗布考(100 mg·kg-1·d-1)直至起搏结束。起搏前和起搏6周后,分别测定各组犬AF诱发率和持续时间;TUNEL法观察心房肌细胞凋亡;Masson染色观察心房间质纤维化;比色法检测丙二醛(MDA)和总抗氧化能力(T-AOC)。免疫组化法和Western-blot法检测心房肌聚ADP核糖聚合酶-1(PARP-1)和凋亡诱导因子(AIF)蛋白表达。结果与假手术组比较,起搏组AF诱发率和持续时间较起搏前显著增加(P0.01),心房肌细胞凋亡指数和心房肌纤维化程度显著增加(P0.01);起搏组MDA水平显著增加,T-AOC水平明显地下降(P0.05),心房肌PARP-1和AIF表达明显增加(P0.001)。与起搏组比较,普罗布考组AF诱发率降低,AF持续时间缩短,MDA水平降低和T-AOC水平提高,心房肌细胞凋亡数量和心房肌纤维化程度减少,PARP-1和AIF蛋白表达下调。结论普罗布考可降低氧化应激程度,下调心房肌PARP-1表达,延缓电重构和心房结构重构,减少AF发生。  相似文献   

3.
探讨快速心房电刺激对人心房有效不应期 (AERP)的影响及卡托普利的干预作用。选择本院行射频消融术的 38例成年患者为研究对象 ,随机分为卡托普利组 (14例 )、维拉帕米组 (12例 )及生理盐水对照组 (12例 )。分别在阻断心脏自主神经后 ,观察各组用药前、后及快速心房刺激后AERP的变化及AF诱发情况。结果 :①快速心房刺激可使 5 7.9%成人正常心脏诱发AF ;②诱发AF后AERP明显缩短 ,而未诱发AF者的AERP无明显变化 ;③卡托普利及维拉帕米均能显著延长诱发AF患者的AERP ;④卡托普利能减少AF诱发率 ,并缩短AF持续时间 ;而维拉帕米则使AF诱发率增加、持续时间延长。结论 :①快速心房刺激可使部分患者AERP缩短 ,并诱发这类患者发生AF ;②卡托普利可显著延长诱发AF患者的AERP ,并使AF诱发率降低、持续时间缩短  相似文献   

4.
目的 探讨星状神经节(SG)刺激诱发急性心房颤动(房颤)及心房电重构与神经重构的机制.方法 将健康家犬12只(18~25kg)随机分为2组:对照组(n=6),单纯快速心房起搏(RAP);SG组(n=6),左侧或右侧SG刺激+RAP.测定房颤诱发率、房颤持续时间,观察心房电重构和神经重分布.结果 ①与基础值相比,SG刺激显著增高房颤诱发率(P<0.05),并延长房颤持续时间(P<0.05);②SG组有效不应期(ERP)显著缩短(P<0.05),ERP离散度显著增加(P<0.05),ERP频率适应性不良(P<0.05);③SG组心肌组织酪氨酸羟化酶(TH)、胆碱乙酰转移酶(ChAT)和生长相关蛋白-43(GAP-43)阳性神经纤维密度均高于对照组(P<0.05).结论 SG刺激使心房和肺静脉部位的房颤诱发率升高,房颤持续时间延长,单侧去SG支配可减少房颤的发生和维持.交感神经活动增强可以引起心房和肺静脉发生电重构以及心房自主神经重构,急性心房电重构和急性自主神经重分布之间的恶性循环,是房颤早期诱发和维持的重要机制.  相似文献   

5.
目的通过快速心房起搏(ATP)建立犬心房心动过速心房重构模型,观察辛伐他汀对急性心房电重构的影响,探讨辛伐他汀防治心房颤动(AF)的作用机制。方法健康成年杂种犬21只(雌雄不拘,体重1012.5 kg)。随机分为三组:对照组ATP组、药物干预组。药物干预组起搏前5 d给予辛伐他汀20 mg/d口服。右侧开胸将电极置于右心耳及右心房侧壁。ATP组和药物干预组以480次/min的频率快速起搏右心房,于实验开始及起搏后6 h对每只犬进行非开放性电生理检查,测定心房有效不应期(AERP)及burst刺激诱发AF频率和AF持续时间。结果对照组在整个时间内AERP无变化。ATP组ATP后,AERP明显缩短。药物干预组ATP后AERP亦缩短,但较ATP组变化明显减轻。各组起搏前AF的频率和持续时间没有差异。对照组在手术前后AF的频率和持续时间无变化。ATP组ATP后AF的诱发频率明显增多和持续时间延长。药物干预组与ATP组比较AF诱发频率及持续时间明显得到抑制。结论心房电重构造成的AERP等电生理变化促进了AF发生和维持。辛伐他汀对ATP引起的犬急性心房电重构具有一定的预防作用,并能削弱ATP对犬AF的促发作用。  相似文献   

6.
目的:观察培哚普利和螺内酯及二者联用对长期心房快速起搏诱发心房纤颤(房颤,AF)犬心房结构和功能重构的影响。方法:实验犬24只,随机分为4组,即对照组、培哚普利组(P组)、螺内酯组(S组)和二者联用组(P+S组)。各组心房快速起搏8周,建立AF犬模型。分别于起搏前、起搏4周及8周测定血浆血管紧张素II(AngII)和醛固酮(Ald)水平;起搏前及起搏后8周,测定左心房结构和功能变化;起搏8周后停止起搏,观察各组犬AF维持的例数及AF自行持续时间;Masson染色检测各组犬心房肌胶原容积分数(CVF)改变。结果:与对照组相比,P组、S组和P+S组犬起搏4周和8周后血浆AngII及Ald水平明显降低,起搏8周后左心房左右径、上下径、收缩末期容积和舒张末期容积明显减小,左心房射血分数显著增大,停止起搏后AF维持率明显减少,AF平均持续时间明显缩短,CVF值明显降低。而3个用药组相比差异无统计学意义。结论:培哚普利和醛固酮受体拮抗剂(螺内酯)能够阻止长期心房快速起搏AF犬心房结构功能的改变及心房纤维化,减少AF发生率及持续时间,但二者联用效果并不优于单药。  相似文献   

7.
目的观察西拉普利和缬沙坦对长期心房快速起搏诱发心房颤动犬心房结构和功能重构的影响,并探讨其机制。方法2006年3月至10月在哈尔滨医科大学第一临床医学院动物实验中心,将实验犬随机分为假手术组(n=6)、对照组(n=7)、西拉普利组(n=7)和缬沙坦组(n=7)。对照组、西拉普利组和缬沙坦组犬心房快速起搏6周,建立心房颤动(AF)犬模型。西拉普利组和缬沙坦组犬分别于起搏前1周开始每天服用西拉普利(1mg/kg)和缬沙坦(30mg/kg),直至起搏结束。分别于起搏前、起搏6周后,超声测定左心房和左心耳结构和功能变化;Masson染色检测各组犬心房肌胶原容积分数(CVF)改变;免疫组化法测定心房肌细胞外信号调节激酶ERK1和ERK2表达情况;末端脱氧核糖核苷酸转移酶介导的dUTP缺口末端标记法(TUNEL法)检测心房肌细胞凋亡情况。结果(1)起搏6周后,西拉普利组和缬沙坦组犬较对照组犬左心房最大及最小容积、左心耳最大及最小容积明显缩小,左心房和左心耳射血分数、左心耳最大正向和负向血流速度显著增大。(2)与对照组犬相比,西拉普利组和缬沙坦组AF犬心房肌ERK1、ERK2表达和CVF值明显降低。结论西拉普利和缬沙坦能够阻止长期心房快速起搏诱发AF犬心房肌纤维化及细胞凋亡,防止AF犬心房结构重构和功能降低。  相似文献   

8.
目的探讨回心草活性成分胡椒碱对心房快速起搏诱发的兔心房急性电重构的预防作用。方法选择新西兰白兔18只,随机分成对照组、心房快速起搏组和胡椒碱+心房快速起搏组(胡椒碱组),每组6只。对照组和心房快速起搏组术前生理盐水3ml/(kg.d)灌胃3d,胡椒碱组术前给予胡椒碱20mg/(kg.d)药物灌胃3d。对照组术中不行心房快速起搏,心房快速起搏组和胡椒碱组术中以最快能维持心房11起搏频率(500~600/min)行快速心房刺激3h,分别于起搏前和起搏后0.5、1.0、1.5、2.0、2.5和3.0h时,测定基础刺激周长分别为200ms和150ms的右心房有效不应期(atrial effective refractory period,AERP),分析AERP频率适应性的变化情况。结果对照组和胡椒碱组AERP200和AERP150随时间无明显变化。心房快速起搏组AERP200和AERP150与心房快速起搏持续时间呈负相关(r=-0.674,P<0.01;r=-0.543,P<0.01),分别在2.0h和2.5h达到最低值(P<0.05)。心房快速起搏组AERP频率适应性与心房快速起搏时间呈负相关(r=-0.307,P<0.05),对照组和胡椒碱组AERP频率适应性均无明显变化。仅在心房快速起搏组可诱发出阵发性心房颤动(房颤),房颤诱发率为50%,平均房颤持续时间为9.3min。结论胡椒碱能够预防心房快速起搏引起的心房电重构。  相似文献   

9.
目的对比犬和兔对心房颤动(Af)和心房扑动(AF)的易患性特点,探讨更理想的房性心律失常建模方法。方法20只新西兰白兔,起搏组(n=11)10Hz快速心房起搏(RAP)2h,对照组(n=9)不起搏,剪下心脏建立Lan-gendorff灌流模型,在左右心房进行电生理扫查。观察心律失常诱发情况;18只健康成年犬,于心耳10HzRAP2h后,在双心房外膜进行电生理扫查,自身前后对照并与兔的起搏组比较心律失常的诱发特点。结果(1)RAP2h后使犬和兔的Af诱发率显著增高,犬的Af比兔的持续时间更长。(2)RAP和对照组新西兰白兔均容易诱发持续AF(7/11比5/9,P=1.000),持续时间在两组间无差异[(39.8±54.4)s比(70.7±62.2)s,P=0.381];18只犬无1例诱发AF。(3)S1S2或S1S1起搏可诱发兔AF,并可被超速起搏终止。结论犬比兔更容易建立Af模型,而新西兰白兔更适于建立AF模型。  相似文献   

10.
目的 探讨犬肾去交感神经对长期快速右房起搏后心房基质和心房颤动﹙AF﹚诱发的影响。方法 20 只犬分为假手术组﹙n=6﹚、右房起搏﹙RAP﹚组﹙n=7﹚和肾去交感神经﹙RSD﹚组﹙n=7﹚三组。假手术组植入起搏器后程控关闭起搏器;RSD 组先行双侧肾交感神经消融,经 6 周恢复后植入起搏器;RAP 组和 RSD 组快速起搏﹙400 ~450 次 / 分﹚右房 5 周。所有犬在试验开始时和终点进行血压测量及电生理检测;处死动物后迅速取左房组织,检测组织心房利钠肽﹙ANP﹚、血管紧张素Ⅱ﹙AngⅡ﹚和醛固酮水平,及组织半胱天冬酶-3﹙Caspase-3﹚、Bax、B 淋巴细胞瘤-2 基因﹙Bcl-2﹚、金属蛋白酶组织抑制剂-1﹙TIMP-1﹚、基质金属蛋白酶-9﹙MMP-9﹚和转化生长因子-β1﹙TGF-β1﹚等蛋白表达。结果 RSD 组犬肾动脉消融 6 周后﹙植入起搏器前﹚收缩压较消融前显著降低﹙P=0. 001﹚;右房起搏5 周后 RSD 组和 RAP 组的收缩压和舒张压较假手术组均明显降低﹙P〈0. 05﹚,且 RSD 组收缩压较 RAP 组更低﹙P =0. 036﹚。与假手术组和 RSD 组相比,RAP 组起搏 5 周后诱发的 AF 持续时间明显延长﹙P 〈0. 05﹚。RAP 组心房有效不应期﹙AERP﹚明显缩短﹙P=0. 002﹚,而 RSD 组 AERP 的缩短无显著性﹙P =0. 087﹚。与假手术组比较,RAP 组犬左房的 ANP、AngⅡ和醛固酮水平显著升高,而在 RSD 组其升高的趋势明显减缓﹙P〈0. 05﹚。与 RAP 组相比,RSD 组犬左房的 Caspase-3、Bax、MMP-9 和 TGF-β1 蛋白表达显著降低,而 Bcl-2 和 TIMP-1 蛋白表达显著升高。结论 肾去交感神经可抑制长期快速右房起搏后 AF 的诱发和心房基质改变。  相似文献   

11.
Eight patients with atrial flutter (AF) and rapid atrial tachycardia (AT) (5 common AF, 1 uncommon AF and 2 AT) were treated with transesophageal atrial pacing (TEAP). In 5 patients no antiarrhythmic agent was used during this study, and in 3 patients procainamide was administrated intravenously. Conversion to sinus rhythm was successfully achieved in 7 patients (5 common AF and 2 AT). Two patients were converted to sinus rhythm immediately after pacing, and transient atrial fibrillation was induced before conversion to sinus rhythm in 5 patients. TEAP failed to terminate the arrhythmia in 1 patient with uncommon AF. Administration of procainamide reduced the atrial rate in 2 common AF and 1 AT, which were successfully converted to sinus rhythm by TEAP, but induced a rapid ventricular response in 2 patients, one of whom also developed hypotension before conversion. No significant complication due to TEAP was observed in this study. In conclusion, TEAP is a noninvasive method with fewer complications and has nearly the same high efficacy for converting AF and rapid AT to sinus rhythm as DC cardioversion or transvenous atrial pacing.  相似文献   

12.
13.
植入型心房除颤器治疗心房颤动的临床应用   总被引:6,自引:1,他引:5  
目的 评估入型心房除颤器(implantable atrial defibrillator,IAD)治疗阵发性和持续性心房颤动(房颤)患者的有效性和安全性。方法 11例患者(8例阵发性房颤,3例持续性房颤)安装了IAD,型吨Metrix^TM3000和Metrix^TM3020。所有的患者在室功能正常,45%存在高血压等基础心脏病。IAD在识别房颤和心室同步化后,通过右房-冠状静脉窦电流路线,发放  相似文献   

14.
目的应用左心房追踪技术(LAVT)评价高血压心房颤动(房颤)和孤立性房颤患者左心房功能。方法实验组为50例房颤患者,分为孤立性房颤组24例,高血压房颤组26例,对照组为25例健康成人,用M型超声测量左心室舒张末期内径(LVEDD)、左心室收缩末期内径(LVESD)、舒张末期室间隔厚度(IVSTd)、舒张末期左心室后壁厚度(LVPWTd),用校正立方体积法(Teich)计算左心室射血分数(LVEF);二维超声测量患者收缩末期左心房前后径(LAD1)、上下径(LAD2)、横径(LAD3),收缩末期右心房上下径(RAD1)、横径(RAD2),应用LAVT测量左心房最大面积(LAAmax)、左心房最大容积(LAVmax)、最小容积(LAVmin)、收缩期左心房充盈速率峰值(dv/dtS)、舒张早期左心房排空速率峰值(dv/dtE)及舒张晚期左心房排空速率峰值(dv/dtA),并计算左心房排空分数(LAEF)。比较左心房的收缩及舒张功能。结果孤立性房颤组LAD1:(42.43±4.24)mm、LAD2:(60.22±5.79)mm、LAD3:(47.90±4.86)mm、RAD1:(55.04±5.06)mm、RAD2:(43.25±2.56)mm、LAAmax、LAVmax、LAVmin、dv/dtE与正常对照组LAD1:(33.81±2.96)mm、LAD2:(47.29±6.79)mm、LAD3:(39.04±3.53)mm、RAD1:(44.34±4.12)mm、RAD2:(36.06±3.16)mm、LAAmax、LAVmax、LAVmin、dv/dtE比较均明显升高(均为P<0.05),孤立性房颤组LAEF、dv/dtS、dv/dtA与正常对照组比较均明显减低(均为P<0.05),LVEDD、LVESD、IVSTd、LVPWTd、LVEF与正常对照组比较差异均无统计学意义(均为P>0.05)。与正常对照组比较,高血压房颤组的LAD1:(45.47±7.33)mm、LAD2:(61.35±7.39)mm、LAD3:(49.27±5.25)mm、RAD1:(56.18±4.36)mm、RAD2:(45.13±3.21)mm、LAAmax、LAVmax、LAVmin、dv/dtE均明显升高,LAEF、dv/dtS、dv/dtA均明显减低(均为P<0.05),LVEDD、LVESD、IVSTd、LVPWTd、LVEF差异均无统计学意义(均为P>0.05)。与孤立性房颤组相比,高血压房颤组LAAmax、LAVmax、LAVmin均明显升高(均为P<0.05),LAEF、dv/dtS、dv/dtE、dv/dtA均明显减低(均为P<0.05),LVEDD、LVESD、IVSTd、LVPWTd、LVEF、LAD1、LAD2、LAD3、RAD1、RAD2差异均无统计学意义(均为P>0.05)。结论 AF患者左心房功能明显下降高血压房颤患者左心房功能损害较孤立性房颤患者明显。LAVT能准确、快速的反映房颤患者左心房大小及功能的变化,在评价左心房功能方面有较高的重复性。  相似文献   

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BACKGROUND: Regional differences in fibrosis, particularly related to the posterior wall and septum, may be important in atrial fibrillation (AF). Using electroanatomic mapping, voltage can be used as a measure of fibrosis. OBJECTIVES: The purpose of this study was to determine if patients with AF have disproportionately lower voltage in the septal and posterior walls of the left atrium. METHODS: Sinus rhythm left atrial electroanatomic maps were used in serial patients presenting for left atrial ablation of AF (8-mm tip). Patients undergoing left atrial mapping for focal atrial tachycardia (AT) were used as a comparison group (4-mm tip). Animal experiments were performed to assess the influence of ablation catheter tip size on voltage amplitude. RESULTS: The posterior and septal walls exhibited the lowest voltages in both groups. Compared with the anterior wall, there was a 3.78-fold greater odds of finding a low-voltage point (<0.5 mV) in the septum (P <.001) and a 3.37-fold greater odds of finding a low-voltage point in the posterior wall (P <.001) in the AF patients; the proportion of low-voltage points by region were not significantly different in the AT group. In the animal model, the mean voltage obtained from an 8-mm ablation catheter was significantly higher (0.30 +/- 0.17 mV) than that obtained from the same points using a 4-mm catheter (0.22 +/- 0.17, P = .05). CONCLUSION: Regional differences in voltage are present in patients with atrial arrhythmias, with AF patients exhibiting significantly more low-voltage areas in the septum and posterior walls.  相似文献   

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Atrial pacing with floating electrodes primarily designed for single lead VDD systems has disadvantages attributable to the floatability of the electrodes. Body and breathing movements cause changes in the position of the atrial dipole that can lead to failure of atrial capture and sensing, and even alternation of the stimulated chamber. We report the induction of typical intranodal tachycardia episodes related to intermittent failure of atrial capture in a patient with an implanted single lead DDD pacing system. Such systems pose a substantial risk of potentially arrhythmogenic asynchronous pacing.  相似文献   

17.
Paroxysmal atrial fibrillation (AF) is the most common arrhythmia following cardiac surgery such as coronary artery bypass grafting (CABG), and often occurs between the second and fourth postoperative days.1,2 The reported incidence of paroxysmal AF after CABG surgery varies widely, from five to 40%, which is lower than in cases of valvular cardiac surgery.3,4 Although this arrhythmia is usually benign and self-limiting, it may also be associated with increased risk of embolic events, haemodynamic instability, haemorrhagic complications, prolonged hospital stay and higher rates of re-admissions, increasing the healthcare costs.5-7Several risk factors have been proposed for paroxysmal AF after CABG or valvular cardiac surgery, such as advanced age, genetic predisposition, chronic obstructive pulmonary disease, heart failure or increased peri-operative ischaemia.8-10 In addition, certain echocardiographic parameters such as left atrial (LA) diameter or left ventricular (LV) function, and electrocardiographic parameters including P-wave duration and P-wave dispersion (Pd) have been shown to be associated with postoperative AF.11-13Although postoperative AF and its predictors after CABG and valvular surgery have been well researched, no study has been performed to explore the incidence or predictors of postoperative AF in patients with LA myxoma. The aim of this study was to identify the prevalence and predictors of postoperative AF in a pure cohort of patients with LA myxoma.  相似文献   

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BACKGROUND: Patient perspectives about their illness experiences, symptoms, and treatment are essential aspects of quality of life and provide direction for patient and provider decision making regarding innovative therapies such as implantable devices for arrhythmia. PURPOSE: The purpose of this qualitative study was to describe: 1) the experience of patients living with symptomatic, drug-refractory atrial fibrillation (AF) and 2) patient experiences and acceptance of treatment with the implantable cardioverter defibrillator (ICD) with atrial therapies (ICD-AT) including ventricular and atrial defibrillation therapy. PARTICIPANTS: Subjects were 3 women and 8 men, 35 to 80 years of age, who received the Medtronic Jewel AF 7250 ICD-AT as therapy for recurrent, drug-refractory AF, had a history of AF for 3 to 20 years and had experienced multiple treatment modalities including frequent external cardioversion in an effort to control their AF. METHODS: A semi-structured interview addressed experiences of symptoms and prior treatment for AF and experiences, concerns, and perceived benefits of the ICD-AT. Interviews were recorded and transcribed verbatim. Narratives were coded and categorized using Atlas Ti(R) software. Qualitative interpretive analysis methods were used to identify key themes. RESULTS: Before ICD-AT, patient themes focused on AF that was: 1) misdiagnosed, minimized, and poorly treated; 2) distressful because of frequent and intense AF symptoms (fatigue, dizziness, shortness of breath, and anxiety) before ICD-AT; 3) limiting of activities of daily living; 4) associated with distress from enduring previous treatment; and 5) associated with the continuous pursuit of successful treatment and maintenance of normalcy. Decision making regarding ICD-AT therapy included weighing symptom or treatment distress versus anticipated risks or benefits, hope for better outcomes, and lack of options. After ICD-AT, themes included positive perceptions of the device because of AF symptom relief, ability to resume normalcy, and medication tolerance; incorporation of shock experiences into life routines; and patient suggestions regarding preparation and social support. IMPLICATIONS: Symptoms of AF have a major negative impact on overall quality of life. Treatment with the ICD-AT confers a sense of security and reduced symptom distress. Greater provider attention to patient preparation and facilitating social support are important for future ICD-AT patient care.  相似文献   

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