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81.
An 11-year-old girl who underwent Mustard's operation for complete transposition of the great arteries in infancy, developed Mobitz type II second-degree AV block 81/2 years later. A transvenous, active fixation left ventricular lead was inserted and connected to a rate responsive pacemaker. Two years later the lead dislodged due to the child's growth. A new active fixation electrode was positioned in the left ventricle below the pulmonary valve, leaving an electrode loop in the ventricle. Such an approach may prevent lead dislodgement due to growth after intraatrial repair for transposition of the great arteries, but regular radiological or echocardiographic follow-up of lead position is recommended in these patients.  相似文献   
82.
Abstract. Twenty-one patients were studied at rest and during exercise after heart transplantation to compare cardiac output measured by thermodilution and impedance cardiography. Exercise was performed on a bicycle ergometer over a limited range of work load (25 and 50 watt) whilst metabolic gas exchange was recorded. One patient was studied at rest whilst his circulation was maintained by a Jarvik-7 artificial heart. The values of cardiac output measured by impedance cardiography corresponded closely with the flow rate from the artificial heart. There was also close agreement between the impedance and thermodilution measurements of cardiac output at rest and during exercise. Both measurements followed the changes in heart rate and oxygen consumption. Both thermodilution and impedance cardiography methods elicited good reproducibility of cardiac output measurements at rest and during exercise. These observations suggest that the noninvasive and continuous record of cardiac output obtained by impedance cardiography can be used for the postoperative monitoring of heart transplant recipients.  相似文献   
83.
目的:探讨心肌细胞内游离钙([Ca^2 ]i)和心肌ATP酶变化在心肌挫伤(MC)后心功能障碍发生机制中的意义。方法:随机选取兔36只,分为6组:正常对照、伤后2、4、8、12、24h,每组6只。经右颈总动脉插管至左心室测左室压力。采用BIM-II型生物撞击机致成MC模型。在上述时相点测定左室压力,并测定心肌细胞内[Ca^2 ]i和心肌匀浆组织及线粒体ATP酶活力。结果:心脏收缩/舒张功能受到损害,心肌细胞内[Ca^2 ]i升高,心肌匀浆组织及线粒体ATP酶下降,相关分析表明心功能障碍与心肌细胞内[Ca^2 ]i含量升高呈明显负相关,与ATP酶活性降低呈明显正相关。结论:MC后心脏功能下降,心肌细胞内[Ca^2 ]i含量升高和ATP酶活性下降可能是其原因之一。  相似文献   
84.
目的 分析分娩期子宫破裂的发病原因及预防措施。方法 回顾分析1985年8月至2001年12月,16a间64例分娩期子宫破裂的临床资料。结果 子宫收缩剂使用不当3l例,占48.4%;胎先露下降受阻13例,占20.3%;子宫疤痕16例,占25%;阴道助产4例,占6.3%。初产妇10例(10.9%);经产妇54例(89.1%)。结论 降低分娩期子宫破裂发生率关键在于加强计划生育工作及围生期保健,严格掌握子宫收缩剂的适应证及剂量;严格首次剖宫产指征;严密观察产程,及时处理异常分娩。  相似文献   
85.
目的探讨脾脏损伤有效的手术治疗方法。方法对手术治疗的64例脾脏损伤的病因、伤情分级、手术方法分析。结果64例脾脏中钝器伤45例,占70.31%,锐器伤19例,占29.69%。Ⅰ~Ⅱ级损伤26例占40.63%,Ⅲ~Ⅳ级损伤38例,占59.38%,64例患者死亡2例,均为Ⅳ级损伤,占3.13%。结论正确的手术方法,积极稳妥地处理合并伤是降低病死率的关键。  相似文献   
86.
曾令雄  余华 《四川医学》2004,25(1):34-36
目的 分析创伤性肝破裂外科多种干预治疗的效果。方法 总结分析1982-2002年我院收治创伤性肝破裂76例的救治方法和病死率。其中Ⅲ级以上的严重肝破裂46例(60.53%)。手术治疗56例,手术方式包括单纯修补、清创性肝切除、规则性肝切除、肝周填塞止血;非手术治疗20例。结果 手术组:治愈44例,术后并发症17例均经保守治疗治愈,死亡12例,其中术中死亡2例;非手术组:治愈12例,好转6例,2例失访。全组治愈64例,死亡12例,病死率15.8%。结论 Ⅰ-Ⅱ级单纯性外伤性肝破裂可保守治疗;手术是治疗创伤性肝破裂的主要措施,正确的手术方式,积极处理合并伤,重视综合治疗可提高救治成功率。  相似文献   
87.
Using an information-theoretic approach, causality between the systolic amplitude in blood pressure and the frequency of the heart beat was analyzed. Blood pressure and ECG were noninvasively recorded in young, healthy subjects. Three successive measurements were performed: during spontaneous breathing and during paced respiration—at frequencies both higher and lower than that of spontaneous respiration. We demonstrate that the amplitude and frequency of the cardiac rhythm are synchronized for most of the time. The synchronization is stronger during paced respiration at a frequency lower than that of spontaneous breathing. Episodes where the cardiac frequency was driven by the systolic pressure were also detected during slow, paced respiration.  相似文献   
88.
Objective Postoperative pericardial effusion commonly occurs after open heart surgery. However, after general thoracotomy such as pulmonary resection, there have been few reports of pericardial effusion. The purpose of this study is to investigate patients with pericardial effusion following pulmonary resection.Methods: Among 2,385 patients with pulmonary resection for lung neoplasm in our institute, eight patients, whose pericardium had never been opened during the operation, developed pericardial effusion. The clinical characteristics of the eight patients were analyzed.Results: Pericardial effusion after pulmonary resection was divided into two subtypes: pericardial effusion in three patients with left thoracotomy occurring within 30 days postoperatively, and pericardial effusion in the remaining five patients with right thoracotomy occurring more than 30 days postoperatively. Pericardiotomy or pericardiocentesis was performed in three symptomatic patients, and the remaining five asymptomatic patients were treated with diuretics. Pericardial effusion disappeared in three of the five patients about 1–3 months after the conservative treatment, while, in the remaining patients, because pericardial effusion had increased gradually, pericardiocentesis was performed.Conclusion: From our experience, the treatment strategy of drainage for early pericardial effusion and diuretics for late pericardial effusion seems to be appropriate. (Jpn J Thorac Cardiovasc Surg 2006; 54:193-198)  相似文献   
89.
目的 介绍胸骨中下段“T”行锯开微创切口、保留后叶装置、连续缝合法人工机械瓣二尖瓣置换术的临床观察结果。方法 本组42例患应用胸骨中下部“T”形锯开微创切口行保留二尖瓣后叶装置人工机械瓣置换术,其中男性18例,女24例,年龄31~56岁。结果 应用该手术技术的患,手术顺利,无术后并发症及死亡。结论 本术式具有安全、创伤小、术后心脏功能恢复快、并发症少等优点。  相似文献   
90.
自发性食管破裂的诊断和外科治疗   总被引:2,自引:0,他引:2  
目的:探讨自发性食管破裂的诊断和外科治疗。方法 :对 14例自发性食管破裂患者的诊断、治疗方法及治疗结果进行回顾性分析。结果:本组确诊时间 2 4 h以内者仅 2例 ,确诊时间大于 2 4 h者 12例 ;一期食管修补、带蒂胸膜覆盖术 3例 ,治愈 1例 ,治疗失败 2例 (其中 1例死亡 ,1例延期行结肠代食管术后治愈 ) ;行破裂段食管切除、胃 -食管吻合术的 5例全部治愈 ;保守治疗 6例 ,治愈及死亡各 3例。结论:早期诊断自发性食管破裂是提高疗效、降低病死率的关键。发病 2 4 h以上者 ,如全身情况允许 ,破裂段食管切除、胃 -食管吻合术的疗效较好。  相似文献   
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