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Background: The left atrial (LA) size is an important predictor of atrial fibrillation (AF) procedural termination and the long-term outcome. We sought to evaluate the long-term outcome in regard to the LA size and procedural termination.
Methods: Eighty-seven consecutive chronic AF patients (72 males, 53 ± 10 years) underwent 3D mapping (NavX) and ablation. A stepwise approach including circumferential pulmonary vein (PV) isolation, linear ablation, and continuous complex-fractionated electrogram (CFE) ablation (targeting fractionation intervals of < 50 ms). Electrical cardioversion was applied to those without any procedural termination. The freedom from AF was defined as the maintenance of sinus rhythm without the use of any class I or III antiarrhythmic drugs after the blanking period.
Results: Among the 87 patients, all received a circumferential PV isolation, 93% a linear ablation, and 59% a continuous CFE ablation. Those with AF procedural termination (n = 30) had a better long-term outcome when compared with those without termination during a follow-up of 21 ± 12 months. Moreover, a Kaplan-Meier analysis showed that in those with an LA diameter of less than 45 mm (n = 49), the freedom from AF rate was higher when procedural termination was achieved (P = 0.004). On the contrary, the outcome was comparable in those with an LA diameter of ≥ 45 mm (n = 38), whether AF procedural termination occurred or not (P = 0.658).
Conclusions: AF procedural termination was related to the long-term success during chronic AF ablation, especially in those with an LA diameter of less than 45 mm. The favorable effect of termination decreased when the LA diameter was ≥ 45 mm.  相似文献   
95.
Introduction: Atrial tachycardia (AT), including focal and reentrant AT, can occur after circumferential pulmonary vein isolation (CPVI). The aim of this study was to investigate the electrophysiological characteristics of induced AT and its clinical outcome.
Methods and Results: In our series of 160 patients with paroxysmal atrial fibrillation (AF), 45 ATs were induced by high-current burst pacing after CPVI in 26 patients. All induced ATs were mapped using a three-dimensional ( 3D) mapping system. Noninducibility was the endpoint of the ablation of the AT. Gap-related AT was considered if the AT was related to the CPVI lesions. A 16-slice multidetector computed tomography scan was performed in all patients to correlate the anatomical structure with electroanatomical mapping. Thirty-five (78%) reentrant ATs and 10 (22%) focal ATs were identified. Of those, 34 were gap-related ATs (24 reentrant and 10 focal ATs). Reentrant AT had more gaps in the left atrial appendage ridge than did focal AT (39.6% vs 0%, P = 0.02). Focal AT had a higher incidence of gap in the PV carina compared with reentrant AT (80% vs 10%, P < 0.001). Reentrant ATs were mostly terminated during the ablation creating the mitral and roof lines with crossing of the gaps. During a mean follow-up of 21 ± 8 months, only one patient (0.6%) with induced mitral reentry had a recurrent AT.
Conclusion: The location of the AT gap may be related with the complex anatomy of the LA. The induced ATs after CPVI can be eliminated by catheter ablation.  相似文献   
96.
Objectives Erythropoietin has anti‐oxidative and anti‐inflammatory activity. We wanted to evaluate its activity in preventing damage to the gastric mucosa. Methods We examined the protective effect of erythropoietin on indometacin‐induced gastric mucosa damage in the rat stomach and compared its potency with that of famotidine. We also measured effects on oxidant and antioxidant parameters in the rat stomach. Key findings Famotidine and erythropoietin 2500 and 5000 IU/kg reduced the ulcer area by 98%, 31% and 58%, respectively, compared with the indometacin group. Superoxide dismutase activity and glutathione level were decreased and myeloperoxidase activity increased in the indometacin group compared with healthy rats. Famotidine and erythropoietin at all doses increased superoxide dismutase and glutathione levels significantly compared with the indometacin group. Myeloperoxidase activity was decreased by erythropoietin and famotidine. Conclusions These results support the view that erythropoietin counteracts the effects of indometacin in inducing gastric ulcer and could be used as a an antiulcer compound. Its antiulcer effect is less potent than that of famotidine. The antiulcerogenic effects of erythropoietin may be related to its intrinsic ability to sustain the activities of free‐radical scavenging enzymes and the bioavailability of glutathione.  相似文献   
97.
Cervical tuberculous lymphadenitis (scrofula) is an infectious granulomatous disease that requires a precise diagnosis. The differential diagnosis involves mainly the pathologic conditions involving the regional lymph nodes and the submandibulary salivary glands. Although tuberculous lesions generally develop secondary to pulmonary disease, clinical manifestations are occasionally seen with no evidence of involvement of the lungs. In this report, a case of tuberculous submandibular lymphadenitis developing after endodontic treatment of the mandibular first premolar tooth is described.  相似文献   
98.
Hereditary spastic paraplegias (HSPs) are a heterogeneous group of neurodegenerative disorders leading to progressive spasticity of the lower limbs. Clinically, HSPs are divided into "pure" and "complicated" forms. In pure HSP, the spasticity of the lower limbs is the sole symptom, whereas in complicated forms additional neurological and non-neurological features are observed. Genetically, HSPs are divided into autosomal dominant (AD), autosomal recessive (AR) and X-linked (XL) forms. Up to date, 30 different HSPs are linked to different chromosomal loci and 11 genes could be defined for AR-HSP, AD-HSP and XL-HSP. SPG11, an AR-HSP (synonym: HSP11), is a complicated HSP associated with a slowly progressive spastic paraparesis, mental impairment and the development of a thin corpus callosum (TCC) during the course of the disease. SPG11 has been previously linked to chromosomal region 15q13 - 15. First, we applied rigid diagnostic criteria to systematically examine 20 Turkish families with autosomal recessive HSP for characteristic features of SPG11. We detected four large Turkish families with AR-HSP and TCC consistent with SPG11. Subsequent genetic linkage analysis of those 4 families refines the SPG11 locus further down to a small region of 2.93 cM with a maximum lod score of 11.84 at marker D15S659 and will guide further candidate gene analysis.  相似文献   
99.
背景:药物、介入或外科治疗均不能从根本上解决心脏缺血梗死后心肌细胞丧失问题.大量研究结果显示自体心脏干细胞移植治疗缺血性心肌病安全可行,可减少梗死瘢痕面积、改善心室重构、提高心脏功能.目前自体心脏干细胞移植治疗缺血性心肌病已进入临床试验阶段.目的:综述近年国内外自体心脏干细胞移植治疗缺血性心肌病的研究进展.方法:第一作者应用计算机检索1998年1月至2012年4月PubMed数据库、中国期刊全文数据库相关文章,英文检索词“autologous, cardiac stem cel s, ischemic cardiomyopathy, transplantation, treatment”;中文检索词“自体,心脏干细胞,缺血性心肌病,移植,治疗”.共检索到82篇相关文献,57篇文献符合纳入标准.结果与结论:经过大量小动物实验和大型动物的前临床实验准备阶段,目前自体心脏干细胞移植治疗缺血性心肌病已经进入临床试验阶段,初步临床试验结果显示自体心脏干细胞移植治疗缺血性心肌病安全、可行、有效.从心脏中分离的心脏干细胞移植到自体缺血梗死的心脏,可以分化生成心肌细胞、内皮细胞、平滑肌细胞,抑制心室重构,改善心脏收缩、舒张功能.相对于其他来源的干细胞移植治疗,自体心脏干细胞移植治疗缺血性心肌病无免疫源性,不存在免疫排斥反应;不存在伦理问题;其趋向分化成心脏细胞系,成瘤率低,相对安全.自体心脏干细胞移植为缺血性心肌病的治疗提供了一条新的途径,有更高的临床应用价值.但目前开展的临床试验较少,观测时间不够长,缺少多中心大样本量的临床试验等,这些都需要进一步研究探索.  相似文献   
100.
目的:探讨应用负压封闭引流技术治疗胫腓骨开放性骨折合并严重软组织损伤的疗效。方法:对14例胫腓骨开放性骨折合并严重软组织损伤患者,进行清创及骨折固定后,应用持续负压封闭引流,6~8 d后拆除敷料。必要时再次行负压封闭引流,二期植皮。结果:14例患者中5例皮肤回植大部分成活,7例患者使用负压封闭引流术治疗后行二期植皮全部...  相似文献   
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