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91.
射频消融迷宫术治疗心房纤颤 总被引:3,自引:0,他引:3
作者采用射频消融迷宫术治疗心房纤颤20例,其中19例合并风湿性二尖瓣病的患者,同时行瓣膜替换术,1例合并房间隔缺损患者进行修复。射频消融的路线采用小板井嘉夫的手术径路。术后16例恢复窦性心律,占80%,未恢复窦性心律的4例,2例为房颤,1例为房扑,另1例为结性心律。射频消融迷宫术耗时短,仅增加钳闭主动脉时间平均20.5分钟,无术后出血的潜在危险。但术后7~10天之内,有18例出现过房颤、房扑、房速等室上性心律失常,可能由于射频消融不均匀,干扰心房的心电活动所致。 相似文献
92.
BERND-DIETER GONSKA KEJIANG CAO ANSELM SCHAUMANN AXEL DORSZEWSKI FRIEDERIKE von zur MÜHLEN HEINRICH KREUZER 《Pacing and clinical electrophysiology : PACE》1994,17(3):542-549
The management of patients after catheter ablation of ventricular tachycardia is not well defined. In this article we summarize recently published results and report our own experience. Factors influencing the clinical outcome of these patients and methods to identify patients with an increased risk of recurrence of ventricular tachycardia are discussed. Furthermore, a review is given on current concomitant therapeutic tools including antiarrhythmic drugs and the implantation of an automatic cardioverter defibrillator. 相似文献
93.
Anin vitro electrophysiological study of the colon from patients with idiopathic chronic constipation 总被引:2,自引:0,他引:2
Charles H. V. Hoyle BSc PhD Michael A. Kamm MD John E. Lennard-Jones MD Geoffrey Burnstock PhD DSc 《Clinical autonomic research》1992,2(5):327-333
Preparations of the circular muscle layer from the sigmoid colon resected from patients with idiopathic chronic constipation were compared, at an electrophysiological level using the sucrose-gap technique, with preparations of the same region of the intestine resected from patients with rectal carcinoma. Non-adrenergic, non-cholinergic inhibitory neuromuscular transmission, represented by inhibitory junction potentials, was present in preparations from both groups. However, the inhibitory response in preparations from constipated patients had a slower or longer time-course than in those from cancer patients. Also, rebound activity following inhibitory transmission was observed in 34% of preparations from constipated patients but was observed in 67% of preparations from cancer patients. Preparations from both groups displayed the same patterns of spontaneous activity and the same proportion of each group was quiescent. The threshold for generation of action potentials and the passive resistance of the smooth muscle membrane were the same in both groups. However, quiescent preparations from constipated patients were less likely to discharge trains of action potentials when the smooth muscle membrane was depolarized than were preparations from cancer patients. These changes in transmission processes and excitability in tissue from constipated patients are discussed in relation to altered states of colonic motility found in people with idiopathic chronic constipation. 相似文献
94.
Dao Yin Xie Stefan Hassenstein Martin Oberhoff Hartmut Hanke Andreas Baumbach Kristian Hohla Karl Konstantin Haase Karl Rüdiger Karsch 《Lasers in surgery and medicine》1993,13(6):618-624
A modified exeimer laser energy delivery system was used to irradiate 100 segments of normal and fibrous aorta in vitro. The laser beam was scanned into 8 fiber bundles consisting of 50 fibers each resulting in a reduction of the applied pulse energy. The total repetition rate was increased to 150 Hz in order to keep the repetition rate per fiber bundle close to 20 Hz and to minimize thermal injury. The results demonstrate that effective ablation (etch rate per 8 pulses > 2.0 μm) occurred at an energy fluency of 50 mJ/mm2 in both normal and fibrous aorta. Tissue damage (carbonization, tissue separation, fissures, cracks, and vacuolization) was in a range of 100 ± 28 to 152 ± 30 μm for normal aorta and in a range of 57 ± 35 to 110 ± 39 μm for fibrous aorta. We conclude that effective ablation of normal and fibrous human aorta can be achieved by the application of smooth excimer laser coronary angioplasty. This improvement of excimer laser technology may result in a reduction of shock wave- and cavitation-induced damage leading to a reduction of tissue injury. However, this awaits further in vitro and in vivo confirmation. © 1993 Wiley-Liss, Inc. 相似文献
95.
The effects of radiofrequency catheter ablation on the metabolic enzymes and Ca++-ATPase of myocytes
Summary Using histochemical technique, the effects of radiofrequency catheter ablation (RFCA) on the activities of LDH, SDH, CCO,
and Ca++-ATPase of guinea-pig ventricular myocytes were examined. The histological changes were observed for comparison. Radiofrequency
energy (500 kHz) delivered was 20 WX 10 s. The results were as follows: RFCA resulted in significant impairments in all the
four kinds of enzymes but without statistical differences in the areas involved in this energy level. No statistically significant
difference was found between the ranges of enzymatic damages and areas of pathological lesions. These findings showed a consistency
in areas of the histological and histochemical lesions resulted from RFCA. 相似文献
96.
导管射频消融治疗房室结折返性心动过速前后心率变异的改变 总被引:1,自引:0,他引:1
对20例房室结折返性心动过速患者在射频消融前后进行心率变异频域和时域分析,以了解射频消融对心脏自主神经系统的影响。结果显示,心率变异的极低频段(ULFP)、低频段(LFP)、高频段(HFP)及总能谱(TFP)均较射频消融前降低(P〈0.05)。提示射频消融对心脏交感神经、融交感神经均有损害,而以副交感神经损害为主。 相似文献
97.
OLE-GUNNAR ANFINSEN ERIK KONGSGAARD ARNOLD FOERSTER HALFDAN AASS JAN P. AMLIE 《Pacing and clinical electrophysiology : PACE》1998,21(1):69-78
Interruption of atrial flutter and fibrillation by RF catheter ablation may be favored by large, elongated lesions. We administered RF current in unipolar and bipolar mode in porcine right atrium. Bipolar ablation was performed between the tip electrodes of two serially coupled catheters. With 4-mm tip electrodes in vitro, lesion length increased from a mean (SD) of 7.9 (1.2) mm at 3 mm-interelectrode distance (IED) to 13.3 (3.3) mm at 9-mm IED, but decreased at 12-mm IED due to nonconfluent lesions (P < 0.0001), With 4 mm distal electrodes and 8 mm IED, bipolar lesions were 65% longer than corresponding unipolar ablations. Switching to bipolar mode increased the lesion length more than increasing electrode tip length to 6 mm in unipolar mode. Power and temperature controlled ablation created equally sized lesions. Twelve anesthetized pigs were randomized to unipolar or two catheter bipolar temperature controlled ablation of the right atrial free wall. Bipolar ablation created confluent lesions with endocardial length × width of 13.5 (5.8) × 7.3 (3.7) mm, unipolar ablation 6.4 (2.8) × 4.6 (1.4) mm (P < 0.001 when comparing length and P = 0.013 for lesion width). The atrial lesions in both groups were transmural and extended into hilar lung lesions with maximal depth of 3.0 (1.1) and 2.6 (1.0) mm, respectively (P = 0.44). Five bipolarly and four unipolarly ablated pigs developed right diaphragmal paresis. We conclude that bipolar ablation may be preferable in situations where large, elongated lesions are favorable. The two catheter technique is feasible in porcine right atrium. Both bipolar and unipolar ablation of the porcine right atrial free wall may frequently be complicated by injury to the phrenic nerve and adjacent lung tissue. 相似文献
98.
Radiofrequency Ablation of Concealed Left Free-Wall Accessory Pathways Without Coronary Sinus Catheterization: 总被引:1,自引:0,他引:1
JOSEP BRUGADA M.D. IGNACIO GARCIA-BOLAO M.D. MARCIO FIGUEIREDO M.D. MARTÍ PUIGFEL M.D. MARIONA MATAS R.N. FRANCISCO NAVARRO-LÓPEZ M.D. 《Journal of cardiovascular electrophysiology》1997,8(3):249-253
Ablation of Concealed Accessory Pathways. Introduction: Feasibility of radiofrequency (RF) ablation using a two-catheter technique without coronary sinus catheterization was studied in 100 consecutive patients with a single concealed left free-wall accessory path-way.
Methods and Results: Tachycardia was induced by electrical stimulation in the right atrium/right ventricle, and the presence of a concealed left free-wall accessory pathway was suggested electrocardiographically (negative P wave in leads I and/or a VL during orthodromic tachycardia) or by earlier atrial activation in the pulmonary artery compared to the high right atrium. Mapping of the mitral annulus was performed during right ventricular pacing or orthodromic tachycardia, and RF energy was applied at the site with the earliest retrograde atrial activation. Ablation was considered effective if tachycardia could not be induced, and if VA dissociation or exclusive retrograde nodal conduction was observed. Ablation was initially successful in 98 of 100 patients. Mean number of radiofrequency pulses were 3.2 ± 2. Mean fluoroscopy time and total procedure time was 14 ± 9 and 107 ± 32 minutes, respectively. There were no complications related to the procedure. At a mean follow-up of 22 ± 13 months, two patients experienced tachycardia recurrence and required a second procedure, which was successful.
Conclusions: Our results suggest that RF catheter ablation of concealed left free-wall accessory pathways can be safely, effectively, and rapidly performed using a simplified two-catheter technique with no need for coronary sinus catheterization. 相似文献
Methods and Results: Tachycardia was induced by electrical stimulation in the right atrium/right ventricle, and the presence of a concealed left free-wall accessory pathway was suggested electrocardiographically (negative P wave in leads I and/or a VL during orthodromic tachycardia) or by earlier atrial activation in the pulmonary artery compared to the high right atrium. Mapping of the mitral annulus was performed during right ventricular pacing or orthodromic tachycardia, and RF energy was applied at the site with the earliest retrograde atrial activation. Ablation was considered effective if tachycardia could not be induced, and if VA dissociation or exclusive retrograde nodal conduction was observed. Ablation was initially successful in 98 of 100 patients. Mean number of radiofrequency pulses were 3.2 ± 2. Mean fluoroscopy time and total procedure time was 14 ± 9 and 107 ± 32 minutes, respectively. There were no complications related to the procedure. At a mean follow-up of 22 ± 13 months, two patients experienced tachycardia recurrence and required a second procedure, which was successful.
Conclusions: Our results suggest that RF catheter ablation of concealed left free-wall accessory pathways can be safely, effectively, and rapidly performed using a simplified two-catheter technique with no need for coronary sinus catheterization. 相似文献
99.
Henry Ahn Payam Mousavi Lee Chin Sandra Roth Joel Finkelstein Alex Vitken Cari Whyne 《European spine journal》2007,16(8):1171-1178
A biomechanical study comparing simulated lytic vertebral metastases treated with laser-induced thermotherapy (LITT) and vertebroplasty
versus vertebroplasty alone. To investigate the effect of tumor ablation using LITT prior to vertebroplasty on biomechanical
stability and cement fill patterns in a standardized model of spinal metastatic disease. Vertebroplasty in the metastatic
spine is aimed at reducing pain, but is associated with risk of cement extravasation in up to 10%. Six pairs of fresh-frozen
cadaveric thoracolumbar spinal motion segments were tested in axial compression intact, with simulated metastases and following
percutaneous vertebroplasty with or without LITT. Canal narrowing under load, pattern of cement fill, load to failure, and
LITT temperature and pressure generation were collected. In all LITT specimens, cement filled the defect without extravasation.
The canal extravasation rate was 33% in specimens treated without LITT. LITT and vertebroplasty yielded a trend toward improved
posterior wall stability (P = 0.095) as compared to vertebroplasty alone. Moderate rises in temperature and minimal pressure generation was seen during
LITT. In this model, elimination of tumor by LITT, facilitates cement fill, enhances biomechanical stability and reduces the
risk of cement extravasation. 相似文献
100.
George Thabit III MD 《Operative Techniques in Sports Medicine》1998,6(3):157-160
The Holmium:YAG (Ho:YAG) laser is the arthroscopic laser of choice. The arthroscopic surgeon can ablate, coagulate, or shrink periarticular soft tissues by manipulating Ho:YAG laser power settings. The ability to ablate soft tissue in a hemostatic fashion greatly facilitates the treatment of labral tear, synovitis, subacromial arch decompression, and distal clavicle arthritis. The nonablative application of Ho:YAG laser energy has been used successfully to treat glenohumeral instability. The laser-assisted capsular shift (LACS) procedure, in conjunction with standard labral repair techniques, successfully treats unidirectional and multidirectional shoulder instability Neuromuscular rehabilitation is accelerated. Excellent clinical results may be achieved with appropriate surgical technique and postoperative rehabilitation. 相似文献