心房颤动持续时间与肺静脉直径的关系

目的:评价心房颤动持续时间、房颤负荷与肺静脉直径的关系。方法:133例经CT检查的房颤患者,观察肺静脉直径的大小,统计分析房颤持续时间与肺静脉直径的关系。结果:通过统计学处理,对比其肺静脉直径与房颤持续时间及房颤负荷间关系,认为两者间无统计学意义,房颤病史与肺静脉直径无明显相关性。结论:房颤持续时间对肺静脉直径不产生影响。     

Atrial natriuretic peptide-dependent modulation of hypoxia-induced pulmonary vascular remodeling

Hypoxic stress upsets the balance in the normal relationships between mitogenic and growth inhibiting pathways in lung, resulting in pulmonary vascular remodeling characterized by hyperplasia of pulmonary arterial smooth muscle cells (PASMCs) and fibroblasts and enhanced deposition of extracellular matrix. Atrial natriuretic peptide (ANP) reduces pulmonary vascular resistance and attenuates hypoxia-induced pulmonary hypertension in vivo and PASMC proliferation and collagen synthesis in vitro. The current study utilized an ANP null mouse model (Nppa-/-) to test the hypothesis that ANP modulates the pulmonary vascular and alveolar remodeling response to normobaric hypoxic stress. Nine-10 wk old male ANP null (Nppa-/-) and wild type nontransgenic (NTG) mice were exposed to chronic hypoxia (10% O(2), 1 atm) or air for 6 wks. Measurement: pulmonary hypertension, right ventricular hypertrophy, and pulmonary arterial and alveolar remodeling were assessed. Hypoxia-induced pulmonary arterial hypertrophy and muscularization were significantly increased in Nppa-/- mice compared to NTG controls. Furthermore, the stimulatory effects of hypoxia on alveolar myofibroblast transformation (8.2 and 5.4 fold increases in Nppa-/- and NTG mice, respectively) and expression of extracellular matrix molecule (including osteopontin [OPN] and periostin [PN]) mRNA in whole lung were exaggerated in Nppa-/- mice compared to NTG controls. Combined with our previous finding that ANP signaling attenuates transforming growth factor (TGF)-beta-induced expression of OPN and PN in isolated PASMCs, the current study supports the hypothesis that endogenous ANP plays an important anti-fibrogenic role in the pulmonary vascular adaptation to chronic hypoxia.     

去自主神经效应对环肺静脉消融房颤疗效的影响

目的：探讨去自主神经效应对环肺静脉消融(CPVA)治疗心房颤动(房颤)的远期成功率的影响。方法：选择104 例药物治疗无 效的、有临床症状的阵发性房颤患者作为研究对象,所有患者均接受CPVA 术。分别于术前、术后进行动态心电图检查,术后每3 个月复查一次动态心电。随访房颤消融成功率(术后3个月无房颤被定义为无复发);并记录动态心电心率变异性(HRV)以反映自 主神经功能。结果：本组研究共104 例患者完成了CPVA术,平均手术次数为(1.35术次数为。变次,成功率为77.9%,共随访(24.27 次数为。变异性个月。根据术后是否发生房颤,将患者分为成功组(81例)和复发组(23 例),所有患者CPVA术后的时域和频域各项 参数均显著降低(P<0.01),两组术后心率变异性(HRV) 各项参数均较术前明显降低,成功组患者的SNDD、SDANN、rMSSD、 PNN50、HF、TF、LF、VLF 较对照组患者呈现不同程度的降低。结论：CPVA术可使心房出现去自主神经效应,进而增加去神经化 效应,有利于提高其治疗房颤的远期成功率。     

肺静脉口弧形指数与房颤消融术后复发的关系

目的:探讨肺静脉口弧形指数与心房颤动(房颤)导管消融术后复发的关系。方法:选取2008年2月至2011年3月在我院接受导管消融术的房颤患者120例,所有患者于术前3日内利用多排CT行左心房及肺静脉造影,并进行图像的三维重建。测量每条肺静脉前后径及上下径,并计算弧形指数(肺静脉前后径/肺静脉上下径)以描述肺静脉口形态。行射频消融治疗的房颤病人全部达消融终点,术后随访超过3个月,根据患者房性快速性心律失常(房颤、房扑或房速)的发生情况,将其分为治愈组和复发组,进行统计分析。结果:由弧形指数分析,四支肺静脉开口形态存在统计学差异(P0.05);房颤消融术后,53例病人复发。房颤消融术后复发患者的LIPV弧形指数与治愈者不同,差异有显著性(P0.05);两组患者的左上肺静脉(Left Superior Pulmonary Vein,LSPV),右上肺静脉(Right Superior Pulmonary Vein,RSPV),右肺下静脉(Right Inferior Pulmonary Vein,RIPV),的弧形指数比较差异不明显(P0.05)。结论:左下肺静脉形态的不一致性与房颤导管消融术复发有关。     

三维标测环肺静脉前庭隔离术后肺静脉狭窄的相关因素

目的:探讨房颤射频消融术后肺静脉狭窄的相关因素,为其预防提供依据。方法:收集113例射频消融房颤患者的临床资料,记录射频术中消融时间、阻抗和温度;术后6个月64层CT左房-肺静脉重建随访,统计肺静脉狭窄的发生率;多元Logistic回归分析肺静脉狭窄的相关因素。结果:依据肺静脉数量计算的肺静脉狭窄率为3.4%,按照患者数量计算的肺静脉狭窄率为7.7%。多元Logistic回归分析,初始50例手术较其后病例的OR为2.167,95%CI=1.038~9.857,P=0.046,消融时间在总消融时间均数之上的患者比在均数之下者OR为2.856,95%CI=1.352~6.043,P=0.021。结论:初始50例手术和消融时间长是房颤射频消融术后肺静脉狭窄的相关因素。     

三维标测环肺静脉前庭隔离术后肺静脉狭窄的相关因素

目的：探讨房颤射频消融术后肺静脉狭窄的相关因素,为其预防提供依据。方法：收集113例射频消融房颤患者的临床资料,记录射频术中消融时间、阻抗和温度;术后6个月64层CT左房-肺静脉重建随访,统计肺静脉狭窄的发生率;多元Logistic回归分析肺静脉狭窄的相关因素。结果：依据肺静脉数量计算的肺静脉狭窄率为3．4％,按照患者数量计算的肺静脉狭窄率为7．7％。多元Logistic回归分析,初始50例手术较其后病例的OR为2．167,95％CI=I．038-9．857,P=0．046,消融时间在总消融时间均数之上的患者比在均数之下者OR为2．856,95％CI=1．352-6．043,P=0．021。结论：初始50例手术和消融时间长是房颤射频消融术后肺静脉狭窄的相关因素。     

Omega-3 Polyunsaturated Fatty Acid Supplementation Reduced Atrial Fibrillation Recurrence after Pulmonary Vein Antrum Isolation

Objective

To assess if patients treated with omega-3(n-3) polyunsaturated fatty acids (PUFAS) had lower procedural failure rates compared to an untreated population.

Methods and Results

From January 2004 to 2007, 1500 PVAI patients underwent catheter ablation. Two hundred and eighty five (19%) patients were treated with PUFAs. These patients were matched in a nested case controlled analysis. After matching, there were 129 patients in the PUFA group and 129 in the control group. Thirty-five (27.1%) patients in the study group had early recurrence vs. 57 (44.1%) in the control group p-value< 0.0001. Twenty-nine (23.2%) patients in the PUFA group vs. 41 (31.7%) in the non-PUFA group had procedural failure (p-value < 0.003). There were no significant differences in complications in the PUFA and non-PUFA groups.

Conclusion

Patients treated with PUFAs had lower incidences of early recurrence and procedural failure compared to an untreated population.     

Navx-guided Cryoablation of Atrial Tachycardia Inside the Left Atrial Appendage

Radiofrequency ablation procedures inside the left atrial appendage (LAA) are likely to involve dangerous complications because of a high thrombogenic effect. Cryoablation procedures are supposed to be safer. We describe two cases of successful cryoablation procedures. Two NavX-guided cryoablations of permanent focal atrial arrhythmias arising from the LAA were performed. Left atrial reconstruction and mapping allowed the zone of the earliest atrial potential to be recorded; the entire course of the ablation catheter was monitored. The arrhythmias were successfully ablated; no thrombotic complications were observed.     

心房重构与心房纤颤的病理学机制研究进展

目前,发生率最高的心率失常被认为是心房纤颤,且该病的发生率随着年龄的增长而上升。伴随着我国人口年龄结构的变化,心房纤颤在我国的发病率逐渐增加。了解该病的发生和发展的机制十分迫切。已经证明,心房重构是该病的重要发生机制。随着研究的加深,研究人员对心房重构与该病的病理学机制有了更加深刻的了解。现就心房纤颤和重构在发病中的机制进行回顾。     

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia, affecting an estimated 6 million people in the United States ¹. Since AF affects primarily elderly people, its prevalence increases parallel with age. As such, it is expected that 15.9 million Americans will be affected by the year 2050 ². Ischemic stroke occurs in 5% of non-anticoagulated AF patients each year. Current treatments for AF include rate control, rhythm control and prevention of stroke ³.The American College of Cardiology, American Heart Association, and European Society of Cardiology currently recommended rate control as the first course of therapy for AF ³. Rate control is achieved by administration of pharmacological agents, such as β-blockers, that lower the heart rate until it reaches a less symptomatic state ³. Rhythm control aims to return the heart to its normal sinus rhythm and is typically achieved through administration of antiarrhythmic drugs such as amiodarone, electrical cardioversion or ablation therapy. Rhythm control methods, however, have not been demonstrated to be superior to rate-control methods ^4-6. In fact, certain antiarrhythmic drugs have been shown to be associated with higher hospitalization rates, serious adverse effects ³, or even increases in mortality in patients with structural heart defects ⁷. Thus, treatment with antiarrhythmics is more often used when rate-control drugs are ineffective or contraindicated. Rate-control and antiarrhythmic agents relieve the symptoms of AF, including palpitations, shortness of breath, and fatigue ⁸, but don''t reliably prevent thromboembolic events ⁶.Treatment with the anticoagulant drug warfarin significantly reduces the rate of stroke or embolism ^9,10. However, because of problems associated with its use, fewer than 50% of patients are treated with it. The therapeutic dose is affected by drug, dietary, and metabolic interactions, and thus requires detailed monitoring. In addition, warfarin has the potential to cause severe, sometimes lethal, bleeding ². As an alternative, aspirin is commonly prescribed. While aspirin is typically well tolerated, it is far less effective at preventing stroke ¹⁰. Other alternatives to warfarin, such as dabigatran ¹¹ or rivaroxaban ¹² demonstrate non-inferiority to warfarin with respect to thromboembolic events (in fact, dabigatran given as a high dose of 150 mg twice a day has shown superiority). While these drugs have the advantage of eliminating dietary concerns and eliminating the need for regular blood monitoring, major bleeding and associated complications, while somewhat less so than with warfarin, remain an issue ^13-15.Since 90% of AF-associated strokes result from emboli that arise from the left atrial appendage (LAA) ², one alternative approach to warfarin therapy has been to exclude the LAA using an implanted device to trap blood clots before they exit. Here, we demonstrate a procedure for implanting the WATCHMAN Left Atrial Appendage Closure Device. A transseptal cannula is inserted through the femoral vein, and under fluoroscopic guidance, inter-atrial septum is crossed. Once access to the left atrium has been achieved, a guidewire is placed in the upper pulmonary vein and the WATCHMAN Access Sheath and dilator are advanced over the wire into the left atrium. The guidewire is removed, and the access sheath is carefully advanced into the distal portion of the LAA over a pigtail catheter. The WATCHMAN Delivery System is prepped, inserted into the access sheath, and slowly advanced. The WATCHMAN device is then deployed into the LAA. The device release criteria are confirmed via fluoroscopy and transesophageal echocardiography (TEE) and the device is released.     

国产房缺封堵器治疗多孔型房缺

目的：评估国产封堵器治疗多孔型房缺的可行性及安全性。方法：在X线及超声引导下对19例多孔型房缺植入国产房缺封堵器,术后常规进行心电图及经胸心脏超声随访半年。结果：所有患者均成功进行了房缺封堵,其中5例放置1枚国产普通型房缺封堵器,7例放置2枚国产普通型房缺封堵器,另7例则分别放置1枚细腰大边型房缺封堵器,术后即刻超声检查1例仍有少许分流,术后1月时随访分流消失,所有患者随访半年未出现明显并发症。结论：国产房缺封堵器可安全应用于多孔型房缺患者的封堵治疗,在经验丰富的先心病介入治疗专科中心,封堵治疗可做为部分多孔型房缺患者的首选治疗。