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21.
A new balloon electrode catheter (10 French) with five or six balloon electrodes placed on the cardiac side was developed for transesophageal atrial pacing and bipolar ECG recording. The diameter of the hemispheric electrodes is 6 mm and the length of the esophageal balloon is 10 cm. The transesophageal atrial pacing threshold was measured with the balloon electrode catheter by transesophageal programmed atrial stimulation (TPS) (n = 54). At the onset of TPS, the feeling, capture fn = 54), and pain voltage threshold (n = 6) were measured by increasing the amplitude of the pacing voltage during high rate bipolar atrial pacing and bipolar atrial ECG recording. In 38 TPS, the capture threshold was lower than the feeling threshold (n = 28). In 16 TPS, the capture threshold was higher than the feeling threshold. In conclusion, painless atrial pacing and excellent ECG recording can be achieved with a multipolar esophageal balloon electrode catheter with a low pacing voltage amplitude and a high P wave amplitude.  相似文献   
22.
The optimal approach to electrical cardioversion of atrial fibrillation includes appropriate patient selection, anticoagulation, careful selection and monitoring of antiarrhythmic therapy, and proper electrical cardioversion technique. The optimal technique requires the use of metal electrodes, with one electrode of at least 8 cm in diameter placed in the anterior position, and the second of 12–13 cm diameter placed posteriorly just below the left scapulae, with generous amounts of the appropriate gel (such as Hewlett-Packard Redux Paste) as the electrode-skin interface and firm pressure to the paddle electrode with the patient in expiration. Thus the anterior-posterior chest diameter is decreased and less air between the electrodes is assured. The initial shock strength should be 200 J. The shock is synchronized with the electrocardiographic QRS complex. This report reviews the justification for these recommendations.  相似文献   
23.
老年心房颤动病人华法林抗凝治疗的有效性安全性评价   总被引:2,自引:0,他引:2  
目的 评价华法林用于老年心房颤动病人抗凝治疗的有效性、安全性。方法 选择符合本研究抗凝标准的132例老年心房颤动病人随机分为两组 ,华法林治疗组 (治疗组 ) 5 8例 ,给予华法林 3mg/ d开始 ,监测凝血酶原时间(PT)及国际标准化比值 (INR) ,7~ 15 d使 INR达到 1.8~ 2 .5范围内 ,以后每月查 1次 INR。若病人增加或减少药物有出血倾向时随时再测 INR。阿司匹林对照组 (对照组 ) 74例 ,给予阿司匹林 30 0 mg/ d,分 2次口服 ,密切随访。结果 治疗组 7~ 15 d,平均 (9.1± 2 .8) d,INR达 1.8~ 3.0 (平均 2 .1± 0 .13) ,其中 INR在 1.8~ 2 .5 (平均 1.92±0 .2 3)之间者占 92 .7% ,治疗组有 1例心瓣膜病人出现脑梗死 ,而对照组有 7例发生脑梗死 ,差异显著 ,其余不良反应率两组差异无显著性。结论 老年心房颤动病人选择华法林 2~ 3mg/ d时 ,加强服药后监测及各药物间的相互作用 ,使 INR保持在 1.8~ 2 .5之间是有效、安全的  相似文献   
24.
Atrial fibrillation (AF) is the most common cardiac arrhythmia among the elderly. Its incidence increases dramatically with increasing age and decreasing left ventrieular function, peaking in subjects with overt congestive heart failure, Because of the unsatisfactory efficacy and possible serious side effects of clinically available anti-AF drugs for AF patients with sick sinus syndrome, pacing techniques have recently been applied in the treatment of AF. The cardiac pacemaker Vitatron  相似文献   
25.
BACKGROUND: The clinical significance of conduction recurrences in isolated pulmonary veins of patients with atrial fibrillation is not established. METHODS: Twenty-two patients with paoxysmal atrial fibrillation underwent successful pulmonary vein isolation. Six months after the procedure, 14 patients were free of atrial fibrillation. Two of these patients were subjected to repeat mapping of the left superior pulmonary vein. RESULTS: There was recurrence of pulmonary vein to left atrium conduction despite complete lack of symptoms or evidence of recurrent atrial fibrillation. CONCLUSION: Successful pulmonary vein isolation with abolition of paroxysmal atrial fibrillation does not confer permanent disconnection of the pulmonary vein musculature from the left atrium.  相似文献   
26.
Off-pump coronary artery bypass grafting has become an attractive surgical alternative for myocar-dial revascularization because of the advantage of myocardial protection and other benefits of patients. However, it is still regarded as a controversial treatment for the coronary artery disease accompanied by atrial fibrillation (AF). A significant number of patients in need of coronary revascularization have chronic AF. Although the Cox-Maze III procedure is the gold standard for the surgical treatment of AF, few of these patients undergo AF operations at the time of their coronary bypass grafting. We report herein a case of the pulmonary vein isolation to eliminate the AF by means of epicardial radiofrequency ablation combined with 2 vessels coronary artery bypass grafting on the beating heart with the aid of cardiopulmonary bypass.  相似文献   
27.
本文研究了57例吸食海洛因患者血浆ANF浓度变化,并与健康对照组进行比较结果显示海洛因成瘾组显著高于对照组(P<0.01),作者认为测定血浆ANF水平可以作为海洛因对心肌损害的一种判断指标。  相似文献   
28.
A 69 year old man was admitted for investigation of right sided pleuritic chest pain and dyspnoea, both of which began suddenly four days before admission. Acute pulmonary embolism was diagnosed. Six months after discharge while on warfarin he died. Necropsy found a 50 mm diameter myxoid tumour arising on the right atrial side of the interatrial septum. This lesion may have been discovered earlier by echocardiography although there were no clear indications for this investigation. Presentation was that of recurrent pulmonary embolism with no obvious source or cause of thrombosis. Patients who are thought to have idiopathic pulmonary embolism should undergo early echocardiography to exclude the rare but treatable diseases of the right heart that may be responsible

Keywords: atrial myxoma  相似文献   
29.
Summary Balloon atrial septostomy is an established method of palliation for several forms of congenital heart disease. Previously performed under fluoroscopic x-ray control, recent reports have demonstrated the utility of transthoracic echocardiographic monitoring. We report the first application of uniplane transesophageal echocardiography (TEE) (6.7-mm probe) as an alternative imaging modality for control of ballon atrial septostomy on neonates in the intensive care unit.  相似文献   
30.
高血压患者左室构型和房性心律失常的关系   总被引:4,自引:0,他引:4  
章辉  朱向明 《高血压杂志》1997,5(3):213-214
目的了解高血压患者左室构型和房性心律失常关系。方法应用超声心动图及动态心电图,测定左室结构及房性心律失常发生率。结果Kleiger3~6发生和构型有联系(P<0.001)。结论左室构型影响房性心律失常。  相似文献   
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