Atrial Tachycardia Confined Within the Left Atrial Appendage

AT Confined Within the LAA. Left atrial tachycardias are often seen following catheter ablation of persistent atrial fibrillation (AF). We report here an unusual case where AF was converted to sinus rhythm following catheter ablation, but ongoing atrial tachycardia confined within the left atrial appendage (LAA) was observed. Although the LAA tachycardia was dissociated from the atrium in sinus rhythm, bidirectional conduction between the left atrium and the LAA was, however, demonstrated after tachycardia termination. (J Cardiovasc Electrophysiol, Vol. 21, pp. 933‐935, August 2010)     

左心耳结构复杂性与非瓣膜性心房颤动患者左心耳血栓形成的关系

目的:探讨左心耳结构复杂性与非瓣膜性心房颤动(NVAF)患者左心耳血栓形成的关系。方法:连续入选拟行射频消融术治疗的NVAF患者295例,记录病史资料和化验指标,进行CHA2DS2-VASc评分。行经食道超声心动图和计算机断层扫描血管造影(CTA)检查了解左心耳有、无血栓形成,以此将患者分为血栓组(n=42)和无血栓组(n=253)。应用CT影像后处理系统对左心房CTA影像进行三维重建,获取每例患者的左心耳形态,将左心耳形态分为单纯型和复杂型两类。分析左心耳血栓形成与各项潜在危险因素的关系。结果:血栓组非阵发性心房颤动(76.2%vs 18.2%)、复杂型左心耳比例(66.7%vs 45.1%)显著高于无血栓组(P均<0.01)。此外,血栓组患者的年龄、心房颤动病程、左心房前后径、B型利钠肽、血尿酸、CHA2DS2-VASc评分均大于无血栓组(P均<0.05)。相对于无血栓组,血栓组患者的高血压、糖尿病、冠心病、慢性心力衰竭、脑卒中/短暂性脑缺血发作/血栓栓塞以及血管疾病的患病率更高(P均<0.05)。多因素Logistic回归分析显示,复杂型左心耳(OR=4.129,95%CI:1.413~12.069)、心房颤动病程(OR=1.021,95%CI:1.006~1.036)、非阵发性心房颤动(OR=13.910,95%CI:4.563~42.406)与CHA2DS2-VASc评分(OR=2.580,95%CI:1.115~5.966)均是左心耳血栓形成的独立危险因素(P均<0.05)。结论:复杂型左心耳为NVAF患者左心耳血栓形成的独立危险因素。     

Posterior Left Atrial Wall Hematoma Mimicking Cystic Intracavitary Atrial Mass

Atrial myxoma is the most common benign primary tumor of the heart most commonly in the left atrium (LA). Cystic or cavitated intracardiac masses are rare. We report the case of a 43‐year‐old male patient admitted with chest infection, hemoptysis, and severe respiratory distress, who had to be ventilated. Chest computed tomography showed bilateral lung consolidation with large mass occupying the region of the LA. Transthoracic echocardiography and transesophageal echocardiography showed a large intracavitary left atrial cystic mobile mass. Open‐heart surgical exploration did not show any mass inside the LA. A posterior left atrial wall hematoma was found and evacuated. Biopsies confirmed the presence of blood clots. Posterior left atrial wall hematoma may appear as left atrial intracavitary cystic mass and should be included in the differential diagnosis of cystic left atrial mass. (Echocardiography 2010;27:E102‐E104)     

Percutaneous Left Atrial Appendage Ligation for Stroke Prevention in Atrial Fibrillation

Prevention of thromboembolic complications in atrial fibrillation remains a tremendous clinical challenge. Knowledge that the left atrial appendage (LAA) is the most common anatomical origin of cardioembolic strokes1 has been the main motivation to develop clinical and procedural strategies to exclude the LAA from the circulation, either surgically or percutaneously. This review discusses the rationale behind these strategies, their relative merits, and future prospects for LAA exclusion strategies.     

Left Atrial Appendage Stenosis

We describe an unusual case with an anatomic narrowing at the opening of the left atrial appendage demonstrated by two-dimensional color Doppler and continuous-wave Doppler transesophageal echocardiography.     

左心耳在预测心房颤动发生脑卒中的作用

成为公共健康沉重负担的心房颤动和相关的血栓栓塞性脑卒中事件仍在以惊人的速度增长。心房颤动导致脑卒中的风险增加了5倍．．因此,预防脑卒中的心房颤动管理仍然是最关键的一方面。现在公认的重点预防措施就是规范抗凝,包括已使用很广泛的华法林和现在出现的新抗凝药如利伐沙班等。而且抗凝药的使用已有据可查。由于左心耳在心房鲡动血栓的发生中起关键作用,所以有目的性地去除或结扎左心耳来预防发生脑卒中就成了一种可替代的治疗方法,尤其是适用于那些不适合口服抗凝药的患者,,现就左心耳预测心房颤动发生脑卒中进行介绍。     

Right and Left Atrial Radiofrequency Catheter Therapy of Paroxysmal Atrial Fibrillation

Ablation of Paroxysmal Atrial Fibrillation. Introduction: (AF), trial fibrillation (AF), the most common arrhythmia, is due to multiple simultaneous wavelets of reentry in the atria. The only available curative treatment is surreal, using atriotomies to compartmentalize the atria. Therefore, we investigated a staged anatomical approach using radiofrequency catheter ablation lines to prevent paroxysmal AF. Methods and Results: Forty-live patients with frequent symptomatic drug-refractory episodes of paroxysmal AF were studied. Progressively complex linear lesions were created by sequential applications of radiofrequency current in the right atrium and then in the left atrium if required. The outcome of the procedure was considered a success when the episodes of AF were either eliminated or recurred at a rate of no more than one episode (lasting < 6 hours) in 3 months. Patients who had no more than one episode per month were considered “improved.” Right atrial ablation organized local electrical activity and led to stable sinus rhythm during the procedure in 18 (40%) of the 45 patients. However, sustained AF remained inducible in 40 of 45 patients, and the lesions failed to produce evidence of a significant linear conduction block/delay in all but four patients. There were no significant complications except for two transient sinus node dysfunctions. The procedure duration and fluoroscopic time were 248 ± 79 and 53 ± 11 min, respectively. Additional sessions were required in 19 patients to treat sustained right atrial flutter or arrhythmias linked to ectopic right or left atrial foci. During a mean follow-up of 11 ± 4 months, right atrial ablation was successful in 15 (33%) patients, ft without medication and 9 with a previously ineffective drug. Nine (20%) additional patients were improved. Ten patients with an unsuccessful outcome then underwent linear ablation in the left atrium. The procedure duration and fluoroscopy time were 292 ± 94 and 66 ± 24 min. A hemopericardium occurred in one patient. Two patients required reablation to treat ectopic atrial foci. Left atrial ablation terminated AF during the procedure in 8 patients, and sustained AF could not he induced in 5. Subsequent success was achieved in A (60%) patients, including 4 without medication, and 1 additional patient was improved. Conclusions: Successful radiofrequency catheter ablation of drug-refractory daily paroxysmal AF is feasible using linear atrial lesions complemented by focal ablation targeted at arrhythmogenic foci. Ablation only in the right atrium is a safe technique providing limited success, whereas linear lesions in the left atrium significantly increase the incidence of stable restoration of sinus rhythm, the inability to induce sustained AF, and the final success rate. The described technique is promising hut must he considered preliminary because significant Improvements are required to optimize lesion characteristics and shorten total procedure duration.     

Resolution of Thrombi in Left Atrial Appendage Aneurysm

Atrial appendage aneurysm is a rare cardiac disease and may be complicated by embolic events and rhythm disturbances. We describe a case of a congenital left atrial aneurysm presenting with a cere-brovascular accident in a 57-year-old female. The diagnosis was made by transesophageal echocardiography, which revealed the presence of intraaneurysmal thrombi. The patient initially received anticoagulant therapy and the thrombi were resolved. Subsequently, she was successfully operated on and the aneurysm was removed. This is the first report of thrombi resolution in a left atrial appendage aneurysm.     

Organized Left Atrial Tachyarrhythmia During Stepwise Linear Ablation for Atrial Fibrillation

Introduction: This study attempted to delineate the mechanism of organized left atrial tachyarrhythmia (AT) during stepwise linear ablation for atrial fibrillation (AF) using noncontact mapping.
Methods and Results: Eighty patients in whom organized ATs developed or induced during stepwise linear ablation for AF were enrolled. Left atrial (LA) activation during ATs was mapped using noncontact mapping. Radiofrequency (RF) energy was delivered to the earliest activation site or narrowest part of the reentrant circuit of ATs. A total of 146 ATs were mapped. Four ATs were characterized as a focal mechanism (cycle length (CL): 225 ± 49 ms). A macroreentrant mechanism was confirmed in the remaining 142 ATs. LA activation time accounted for 100% of CL (205 ± 37 ms). All 142 ATs used the conduction gaps in the basic figure-7 lesion line. There were three types of circuits classified based on the gap location. Type I (n = 68) used gaps at the ridge between left atrial appendage (LAA) and left superior pulmonary vein (LSPV). Type II (n = 50) used gaps on the LA roof. Type III (n = 24) passed through gaps in the mitral isthmus. Ablation at these gaps eliminated 130 ATs. During the follow-up period of 16.2 ± 6.7 months, 82.5% of the 80 patients were in sinus rhythm.
Conclusion: The majority of left ATs developed during stepwise linear ablation for AF are macroreentrant through conduction gaps in the figure-7 lesion line, especially at the LAA–LSPV ridge. Noncontact activation mapping can identify these gaps accurately and quickly to target effective catheter ablation.     

超声心动图技术评价心房颤动患者左房功能的应用

左房功能对于维持左室功能有重要意义,超声心动图技术是评价心房颤动患者左房功能最常用的方法,现就近年来常用的关于评价左房功能的各种超声指标进行总结。     

1 041例非瓣膜性心房颤动患者左心房内径的分析

目的:了解非瓣膜性心房颤动(房颤)患者左心房内径与房颤类型、房颤病程、左心房血栓及血栓栓塞危险因素等方面的关系. 方法:选择2001-01至2008-01在我院住院的非瓣膜性房颤患者共1 041例,入选条件:①心电图或24小时动态心电图证实的房颤发作;②超声心动图证实的非瓣膜性心脏病.分组情况:按左心房有无血栓分为无左心房血栓组(,n=950)与有左心房血栓组(n=91). 结果:1 041例患者中,男性666例,女性375例,平均年龄为(64.26 ±12.43)岁.左心房增大的有658例(63.2%).左心房内径随着病程出现阵发性、持续性、永久性房颤而增加,左心室射血分数随着病程出现阵发性、持续性、永久性房颤而降低,持续性房颤和永久性房颤与阵发性房颤比较,差异均有统计学意义(P<0.05).左心房内径的大小随着房颤病程延长而增加.有左心房血栓组的房颤病程、左心房内径大于无左心房血栓组,差异有统计学意义(P<0.05),且具有房颤血栓栓塞危险因素的发生率有随着左心房内径增大而增加的趋势. 结论:房颤是左心房扩大的原因之一,房颤持续时间越长,左心房扩大越明显.左心房扩大在其血栓形成中起着重要作用.