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81.
Transvenous parasympathetic nerve stimulation in the inferior vena cava and atrioventricular conduction 总被引:1,自引:0,他引:1
Schauerte P Scherlag BJ Scherlag MA Jackman WM Lazzara R 《Journal of cardiovascular electrophysiology》2000,11(1):64-69
INTRODUCTION: In previous reports, we demonstrated a technique for parasympathetic nerve stimulation (PNS) within the superior vena cava, pulmonary artery, and coronary sinus to control rapid ventricular rates during atrial fibrillation (AF). In this report, we describe another vascular site, the inferior vena cava (IVC), at which negative dromotropic effects during AF could consistently be obtained. Moreover, stimulation at this site also induced dual AV nodal electrophysiology. METHODS AND RESULTS: PNS was performed in ten dogs using rectangular stimuli (0.1 msec/20 Hz) delivered through a catheter with an expandable electrode basket at its tip. Within 3 minutes and without using fluoroscopy, the catheter was positioned at an effective PNS site in the IVC at the junction of the right atrium. AF was induced and maintained by rapid atrial pacing. During stepwise increase of the PNS voltage from 2 to 34 V, a graded response of ventricular rate slowing during AF was observed (266 +/- 79 msec without PNS vs 1,539 +/- 2,460 msec with PNS at 34 V; P = 0.005 by analysis of variance), which was abolished by atropine and blunted by hexamethonium. In three animals, PNS was performed during sinus rhythm. Dual AV nodal electrophysiology was present in 1 of 3 dogs in control, whereas with PNS, dual AV nodal electrophysiology was observed in all three dogs. PNS did not significantly change sinus rate or arterial blood pressure during ventricular pacing. CONCLUSION: Stable and consistent transvenous electrical stimulation of parasympathetic nerves innervating the AV node can be achieved in the IVC, a transvenous site that is rapidly and readily accessible. The proposed catheter approach for PNS can be used to control ventricular rate during AF in this animal model. 相似文献
82.
Hirotaka Tokai Susumu Eguchi Akihiko Soyama Masaaki Hidaka Mitsuhisa Takatsuki Yujo Kawashita Yoshitsugu Tajima Takashi Kanematsu 《Journal of hepato-biliary-pancreatic sciences》2008,15(5):528-530
A 54-year-old woman was admitted to our hospital following the diagnosis of decompensated liver cirrhosis with hepatitis C. She underwent living-donor liver transplantation, performed using the left hepatic lobe with the middle hepatic vein donated by her husband. After the transplantation, the patient suffered from massive ascites with liver dysfunction. Computed tomography demonstrated stenosis of the suprahepatic inferior vena cava (IVC) with focal collection of fluid. A second laparotomy was performed 19 days after the transplantation. When the encapsulated localized ascites on both sides of the IVC was opened, the ascites was flushed away. Subsequently, the grafted liver was easily mobilized and it was placed in the natural position without any tension, and the pressure gradient of the IVC was improved. Herein, we report a very rare case of compression stenosis of the IVC resulting in Budd-Chiari syndrome caused by localized encapsulated ascites. 相似文献
83.
目的:分析鼻内镜下下鼻甲粘膜下吸切术治疗肥厚性鼻炎的疗效。方法回顾2012年1月—2013年6月该院收治的100例肥厚性鼻炎患者的临床资料,根据手术方法的不同将患者分成对照组和观察组,各50例。对照组采用下鼻甲部分切除术治疗,观察组采用鼻内镜下下鼻甲粘膜下成形术治疗,比较两组手术时间、术中出血量、粘膜恢复时间、鼻腔通气时间以及术后半年的疗效和并发症发生率。结果两组术中出血量、粘膜恢复时间、鼻腔通气时间以及术后半年的疗效比较,差异有统计学意义(P<0.05),且观察组优于对照组,但观察组的手术时间较对照组长,差异有统计学意义(P<0.05);两组均无并发症发生。结论采用鼻内镜下下鼻甲粘膜下成形术治疗肥厚性鼻炎,术中出血量和术后并发症少,安全性高,且患者恢复快,临床疗效良好,具有推广应用价值,但手术时间较长,技术上有待提高。 相似文献
84.
Shijie Huang Tianbao Yang Wu Wang Guozhong Huang Boyang Chen Pengfei Chen Douli Ke Wenhua Huang Jinbiao Xie 《Medicine》2021,100(23)
To evaluate the necessity, safety, and feasibility of left inferior pulmonary ligament lymphadenectomy during video-assisted thoracic surgery (VATS) radical esophagectomy via the right thoracic approach.Thirty patients (20 men, 10 women) with thoracic esophageal squamous cell carcinoma (ESCC) were recruited for this study. The patients’ age ranged from 50 to 80 years, with an average age of 66.17 ± 7.47 years. After the patients underwent VATS radical esophagectomy and left inferior pulmonary ligament lymph node dissection (LIPLND) via the right thoracic approach, the operative outcomes included operative time, length of hospital stay, postoperative complications, number of lymph nodes removed, and postoperative pathologic results were evaluated.There were no massive hemorrhages of the left inferior pulmonary vein during the operation. The operative time of LIPLND was 8.67 ± 2.04 minutes, and the length of postoperative hospital stay was 12.23 ± 2.36 days. The postoperative complications included 2 cases of left pneumothorax, 4 pulmonary infection cases, and no chylothorax. Moreover, 68 LIPLNs were dissected, 5 of which were positive, and the degree of metastasis was 7.4%. The postoperative pathologic results showed that 3 cases of LIPLNs were positive, with a metastasis rate of 10.0%. Among them, 2 cases were SCC of the lower thoracic esophagus, and 1 case was SCC of the middle thoracic esophagus, which involved the lower segment.Thoracoscopic esophagectomy combined with left inferior pulmonary ligament lymphadenectomy for esophageal carcinoma via the right thoracic approach will not increase the difficulty of operation, increase the incidence of postoperative complications or prolong the postoperative hospital stay, and can theoretically reduce tumor recurrence. Therefore, we believe that LIPLND is necessary, safe, and feasible and is worthy of clinical popularization and application. 相似文献
85.
Hepatocellular carcinoma (HCC) involving the inferior vena cava rarely occurs, but its prognosis is extremely poor, with no established treatment to date. This study aimed to analyze the clinical outcome and toxicity of radiotherapy (RT) targeting inferior vena cava tumor thrombus (IVCTT) in HCC patients.From November 2011 to July 2020, medical record of 19 HCC patients who were treated with RT for IVCTT was retrospectively reviewed. RT was delivered using 3-dimensional conformal radiation therapy, intensity-modulated radiation therapy, and stereotactic body radiation therapy. The median radiation dose was 50 Gy (range, 45–55.8 Gy) for intensity-modulated radiation therapy and three-dimensional conformal radiotherapy. Stereotactic body radiation therapy was performed in 5 patients, for a total of 32 Gy in 4 fractions.The median follow-up duration was 8.1 months (range, 3.3–26.5 months). The median overall survival was 9.4 months (range, 3.7–26.5 months), and the 1-year overall survival rate was 37.1%. Eight of 19 patients (42.1%) had extrahepatic metastasis at the start of RT. Six of 11 patients (54.5%) who did not have extrahepatic metastasis at the start of RT showed extrahepatic metastasis after RT. The major cause of death was progression of extrahepatic metastasis (11 patients, 57.9%). The overall response rate of IVCTT for RT was 84.2%, and the local control rate at the time of the last follow-up was 89.4%. After RT, the most common first progression site was the lungs (9 patients, 47.4%). Most toxicities were grade 1 to 2 gastrointestinal (26.3%) and liver enzyme elevation (68.4%). Three patients occurred pulmonary embolism after RT later than 5 months after.RT is a feasible and safe local therapy for IVCTT, with favorable tumor control and acceptable toxicity. Extrahepatic metastasis is the major progression pattern and a leading cause of death in patients treated with RT. The combination of effective systemic therapy with RT may have to be considered. 相似文献
86.
Nerve injury especially inferior alveolar nerve (IAN) is the one of the complications that occur when the mandibular third molar (M3) is extracted and in case of high risk patients, coronectomy might be an alternative to tooth extraction. The purpose of this retrospective study was to analyze root migration and its influencing factors at 6 months after coronectomy in both 2- and 3-dimensions using periapical view and cone-beam computed tomography (CBCT). We analyzed 33 cases of root remnant after coronectomy and measured the amount of migration in CBCT. The following factors that could possibly affect root migration were also analyzed: age, gender, number of M3 roots, shape of M3s, Pell, and Gregory classification, mesiodistal (MD) angulation, buccolingual (BL) angulation, contact point with the second molar, root curvature, and complete removal of the coronal portion. Migration of greater than 2 mm was found in 64% of the roots in the 2-dimensional (2D) analysis, and the average root migration was 4.11 mm in the 3-dimensional (3D) analysis. The factors affecting migration were the root morphology, complete removal of the coronal portion, impaction depth, and MD angulation in the 2D analysis, and MD and BL angulation in the 3D analysis. Ensuring sufficient space for root migration especially considering angulation, depth and complete removal of the coronal portion might be important factors after coronectomy of the M3. Root remnant after coronectomy of M3 may migrate in young patients who has sufficient empty coronal space and this may reduce the nerve damage by the separation of IAN and M3. 相似文献
87.
88.
Primary tumors of the inferior vena cava (IVC) are rare. The most common primary malignancy is leiomyosarcoma (LMS), with a severe prognosis. Right‐atrium (RA) involvement is seen in about 20 percent of cases. We report the case of a 53‐year‐old woman admitted to the intensive care unit because of progressive dyspnea with lower limb edema. Echocardiography demonstrated a large mass in the RA. At open‐heart surgery, the tumor appeared located in the IVC infrahepatic segment, completely obstructing the lumen and extending into the suprahepatic portion and the RA. Histopathological examination concluded to LMS. 相似文献
89.
目的::观察伴有下斜肌功能亢进的外斜V征患者下斜肌和内直肌中myogenin活性卫星细胞数量的变化,探讨伴有下斜肌功能亢进的外斜V征的可能发病原因。方法:将伴有下斜肌功能亢进外斜V征患者6例中切除的下斜肌及内直肌作为斜视组,行myogenin免疫组织化学染色,统计myogenin阳性染色的卫星细胞核数;角膜移植供体的下斜肌及内直肌(6例)作为对照组。结果:斜视组和对照组下斜肌中myogenin免疫染色阳性肌卫星细胞数占总细胞数比例分别为(22.7±7.03)%和(4.2±0.75)%,具有统计学差异(P<0.05)。斜视组和对照组内直肌中myogenin免疫染色阳性的肌卫星细胞数分别为(2.2±0.75)%和(4.5±1.05)%,具有统计学差异(P<0.05)。结论:首次报道伴有下斜肌功能亢进外斜V征患者眼外肌中表达 myogenin 免疫染色阳性肌卫星细胞的变化。myogenin可能是伴有下斜肌功能亢进外斜 V 征的致病因素。 相似文献
90.
目的:对单纯行下斜肌后徙手术后水平斜视度的变化分析,探讨下斜肌后徙手术对原在位水平斜视度的影响.方法:收集2014-01/09在我院眼科行手术治疗的先天性上斜肌麻痹合并小角度水平斜视及小度数Ⅴ型斜视患者共30例,仅行下斜肌后徙手术,水平方向小度数斜视未行手术矫正.其中,先天性上斜肌麻痹患者25例,行单眼下斜肌后徙术;Ⅴ型斜视5例,行双眼下斜肌后徙术.随访3~6mo,术前、术后行33cm和6m三棱镜交替遮盖斜视度检查,同视机检查,Titmus立体图检查,Worth四点灯检查,眼球运动检查,眼底照相检查等,进而比较手术前后远、近水平斜视度变化(双侧者以1/2斜视度计算).结果:(1)外斜组23例(包括5例外斜Ⅴ征)手术前后看远、看近水平斜视度变化有统计学意义(P=0.00),术后分别使原在位外斜减小平均值3.35±2.87△,4.37±2.65△.(2)内斜组7例看远手术前后水平斜视度变化有统计学意义(P=0.02),术后使内斜减小平均值2.43±1.99△;看近手术前后水平斜视度变化无统计学意义(P=0.089).结论:下斜肌后徙手术后原在位外斜、内斜度数都有减小,这种变化通过手术后逐步完善、建立的融合功能代偿产生. 相似文献