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21.
BackgroundContact-force sensing catheter is widely used for catheter ablation, however, it did not take account of radiofrequency power. Ablation index (AI) is a novel marker incorporating contact force-time-power, was shown to be reliable in predicting lesion size and depth for radiofrequency delivery. We aimed to assess the latest evidence on ablation index guided procedure versus conventional ablation procedure.MethodsWe performed a comprehensive search on topic that assesses ablation index guided procedure versus conventional procedures from inception up until February 2019 through PubMed, EuropePMC, EBSCOhost, Cochrane Central Database, and ClinicalTrials.gov.ResultsA total of 1727 subjects from five studies were included. 12 months’ incidence of AF/AT/AFL was lower in ablation index guided with an OR of 0.35 [0.17, 0.73], p = 0.005; I2 58%. Upon sensitivity analysis by removing a study, heterogeneity decreased to 0% with OR of 0.26 [0.15, 0.46], p < 0.001. First-pass isolation has a pooled OR of 11.29 [4.68, 27.20], p < 0.001; I2 58%. Pooled OR for acute pulmonary vein reconnection was 0.43 [0.29, 0.64], p < 0.001; I2 46%. AI group has a shorter fluoroscopy time of MD -1.62 [-2.62, ?0.62] minutes, p = 0.001; I2 51% and total ablation time MD -9.96 [-17.16, ?2.76] minutes, p < 0.001; I2 95%. Total procedural time and complication rate were similar.ConclusionAblation index guided procedure resulted in a significantly lower incidence of AF/AT/AFL, shorter fluoroscopy time, and total ablation time. First-pass isolation was higher in AI group and acute PVR was lower in AI group. Ablation-index guided procedure has a similar safety profile to conventional ablation.  相似文献   
22.
23.
摘要 目的:探讨实时影像融合的超声虚拟导航技术联合射频消融术治疗原发性肝癌合并门静脉癌栓患者的疗效及对血清BCL-2同源的水溶性相关蛋白(Bax)、细胞角蛋白19片段(Cyfra21-1)的影响。方法:选择本院2017年1月到2021年4月收治的原发性肝癌合并门静脉癌栓患者82例作为研究对象,根据1:1随机数字表法将患者分为虚拟导航组与对照组各41例,虚拟导航组给予实时影像融合的超声虚拟导航技术联合射频消融术治疗,对照组给予单纯超声引导联合射频消融术治疗。结果:虚拟导航组的进针次数、融合时间、布针时间少于对照组(P<0.05);虚拟导航组治疗后3个月的胆汁瘤、肝脓肿、膈肌损伤、肺部感染等并发症发生率为4.9 %,低于对照组的29.3 %(P<0.05)。虚拟导航组治疗后3个月的总有效率为82.9 %,高于对照组的51.2 %(P<0.05)。两组治疗后3个月的血清谷丙转氨酶(ALT)、谷草转氨酶(AST)水平低于治疗前,虚拟导航组低于对照组(P<0.05)。两组治疗后的血清Bax、Cyfra21-1含量低于治疗前,虚拟导航组低于对照组(P<0.05)。结论:实时影像融合的超声虚拟导航技术联合射频消融术治疗原发性肝癌合并门静脉癌栓能降低血清Bax、Cyfra21-1含量,改善患者的肝功能,提高消融效率,还可减少并发症的发生,最终提高患者的总体治疗效果。  相似文献   
24.
准分子激光切削角膜的数学模型与切削技术研究   总被引:9,自引:2,他引:7  
本文在分析国内外研究人眼角膜的数学模型的基础上,提出了能够用于进行近视、远视、散光等屈光手术的数学模型,并就准分子激光的切削原理和“飞点扫描”技术进行了研究,本文的研究成果直接用于准分子激光眼科治疗机,取得了满意的手术效果。  相似文献   
25.
We previously reported that transgenic ablation of gonadotrophs results in impaired development of cells immunostainable for prolactin (PRL) but not of cells immunostainable for growth hormone (GH) or proopiomelanocortin (POMC) in pituitary of newborn mice. The question remained whether this reduction in PRL protein is a reflection of reduced PRL mRNA expression, or whether this regulation is only situated at the translational level. We therefore generated a new series of transgenic mice in which gonadotrophs were ablated by diphtheria toxin A targeting, and analyzed hormone mRNA levels instead of hormone protein around the day of birth. Pituitary mRNA expression levels of luteinizing hormone- (LH), PRL and GH were quantified using real-time TaqMan RT-PCR. Of the 13 transgenic mice obtained, 8 showed a clear-cut reduction (ranging from 62 to 98%) in LH mRNA levels. PRL mRNA values were significantly reduced in the transgenic mice (p=0.0034), while GH mRNA expression was unaffected (p=0.93). An additional observation was that female newborn mice produce 5 times more LH mRNA than male mice whereas no sex difference was observed for expression levels of PRL and GH mRNA. Moreover, in the wild-type mice, LH mRNA expression was 20-fold higher than GH mRNA expression which in turn was 500- to 1,000-fold higher than PRL mRNA expression, suggesting a low expression level of the PRL gene at birth. In conclusion, the present data support the hypothesis that embryonic development of PRL gene expression is stimulated by gonadotrophs.  相似文献   
26.
郑剑光  陶新智 《蛇志》1998,10(1):19-21
目的探讨应用导管射频消融(RFCA)治疗特发性室性心动过速的疗效。方法经皮穿刺左右侧股静脉右侧股动脉(起源于左室时),将多根6F或7F4极导管送至高位右房(HRA)、房束(HBE)、右室心尖(RVA)、右室流出道(RVOT)或左室(LV),作短阵快速和程序刺激心室诱发VT,同步记录12导联及心腔内各部位电图。结果除1例不能坚持RFCA外,成功11例(91.7%),另1例因疗效不满意改用导管心内膜直流电消融而获成功。结论术前诊断及靶点标测的准确性是RFCA治疗成功的关键。  相似文献   
27.
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。  相似文献   
28.
Lack of sensory feedback during laser surgery prevents surgeons from discerning the exact location of the incision, which increases duration and complexity of the treatment. In this study we demonstrate a new method for monitoring of laser ablation procedures. Real‐time tracking of the exact three dimensional (3D) lesion profile is accomplished by detection of shock waves emanating from the ablation spot and subsequent reconstruction of the incision location using time‐of‐flight data obtained from multiple acoustic detectors. Here, incisions of up to 9 mm in depth, created by pulsed laser ablation of fresh bovine tissue samples, were successfully monitored in real time. It was further observed that, by utilizing as little as 12 detection elements, the incision profile can be characterized with accuracy below 0.5 mm in all three dimensions and in good agreement with histological examinations. The proposed method holds therefore promise for delivering high precision real‐time feedback during laser surgeries. (© 2013 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)  相似文献   
29.
A recently developed computerized method for estimation of myocardial perfusion, based on the analysis of the time-density curves, is demonstrated to assess myocardial blush over a selected myocardial region of interest in a patient with obstructive hypertrophic cardiomyopathy before and after alcohol septal ablation.  相似文献   
30.
The androgenic glands (AG) of male decapod crustaceans produce insulin-like androgenic gland (IAG) hormone that controls male sex differentiation, growth and behavior. Functions of the AG are inhibited by gonad-inhibiting hormone originating from X-organ-sinus gland complex in the eyestalk. The AG, and its interaction with the eyestalk, had not been studied in the blue swimmer crab, Portunus pelagicus, so we investigated the AG structure, and then changes of the AG and IAG-producing cells following eyestalk ablation. The AG of P. pelagicus is a small endrocrine organ ensheathed in a connective tissue and attached to the distal part of spermatic duct and ejaculatory bulb. The gland is composed of several lobules, each containing two major cell types. Type I cells are located near the periphery of each lobule, and distinguished as small globular cells of 5-7 μm in diameter, with nuclei containing mostly heterochromatin. Type II cells are 13-15 μm in diameter, with nuclei containing mostly euchromatin and prominent nucleoli. Both cell types were immunoreactive with anti-IAG. Following bilateral eyestalk ablation, the AG underwent hypertrophy, and at day 8 had increased approximately 3-fold in size. The percentage of type I cells had increased more than twice compared with controls, while type II cells showed a corresponding decrease.  相似文献   
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