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排序方式: 共有10000条查询结果,搜索用时 23 毫秒
41.
Emad Dean Nukta Bernhard Meier Philip Urban Thierry Muller Pierre A. Dorsaz Josiane Favre 《Catheterization and cardiovascular interventions》1992,25(4):272-277
The Magnum system, initially designed for coronary angioplasty (PTCA) of chronic total occlusion, consists of a balloon catheter and a solid steel 0.021 inch (0.53 mm) steerable and removable wire with a soft and moldable distal portion, tipped with a 1 mm olive. To evaluate its performance in routine PTCA, 200 unselected consecutive patients were randomized to two equal groups, i.e., group Magnum (100 patients, 115 vessels) and group Standard (100 patients, 118 vessels) including 18 and 21 patients with chronic total occlusions, respectively. Randomization was performed by the sealed envelope system in the catheterization laboratory and crossover of system was imposed if it was not possible to place a balloon correctly within 20 min of fluoroscopy time. There were no significant differences between groups concerning clinical and angiographic baseline characteristics, size of initial balloons (3.0±0.3 mm in both groups), fluoroscopy time to cross the lesion with the wire (Magnum: 4±5, Standard: 5±6 min), total fluoroscopy time (Magnum: 11 ± 9, Standard: 12±12 min), and need for crossover (Magnum: 10%, Standard: 16%). Success rates per lesion were comparable with 90% in group Magnum and 84% in group Standard, as were the complications with one inhospital death in group Standard, occurring three weeks after PTCA and stent implantation. There was no emergency operation. Six patients per group had myocardial infarction of whom two in group Magnum and one in group Standard developed a Q-wave. The following variables were significantly in favor of the Magnum system compared with the Standard system: success rate in nontotal lesions (97% versus 90%) crossover success in total occlusions (0 vs. 33%), fluoroscopy time to cross the lesion with the balloon once the wire was in place (1 ± 2 vs. 2 ± 4 min), and use of a single versus 1.2±0.5 wires per lesion. The only advantage of the Standard systems was the more common use of 7 French guiding catheters (Magnum: 40%, Standard: 53%, p = 0.09). The Magnum system compares favorably with standard systems for routine PTCA. The robust design of the Magnum wire does not impair ease of placement and safety but saves material and facilitates balloon advancement across the lesion. 相似文献
42.
目的对比分析胃镜下应用探条或自制气囊扩张治疗贲门失弛缓症的疗效。方法1998年1月~2007年12月,胃镜下治疗贲门失弛缓症45例,其中应用自制气囊扩张22例(自制气囊组),应用探条扩张23例(探条组),比较2组疗效。结果探条组23例扩张1~9次,平均3.6次;自制气囊组22例扩张1~6次,平均2.3次。2组术中及术后均无并发症发生。首次治疗费用探条组(1542.57±281.30)元,自制气囊组(861.91±176.48)元(t=9.671,P=0.000)。扩张后3个月的疗效2组差异无显著性[探条组显效14例(61%)、有效8例(35%)、无效1例(4%),自制气囊组显效15例(68%)、有效5例(23%)、无效2例(9%),Z=-0.351,P=0.726]。扩张后6个月的疗效2组差异有显著性[探条组显效5例(22%)、有效3例(13%)、无效15例(65%),自制气囊组显效10例(45%)、有效7例(32%)、无效5例(23%),Z=2.564,P=0.010]。结论胃镜下应用探条和自制气囊扩张治疗贲门失弛缓症安全、简便,患者恢复快,尤其自制气囊扩张器设备简单,就地取材,疗效肯定,在基层医院具有良好的推广价值。 相似文献
43.
44.
目的:探讨3D—DSA在颅内动脉瘤诊断和治疗中的应用价值。方法:对蛛网膜下腔出血患者常规行DSA检查,发现病变或可疑病变后行3D—DSA检查。结果:26例颅内动脉瘤中检出动脉瘤31枚,其中后交通9枚,C1段3枚,C2段5枚,C3段3枚,前交通6枚,大脑中3枚。椎动脉动2枚。3例2D—DSA未见病变3D—DSA确诊,5例因血管重叠3D—DSA排除了动脉瘤。6枚GDC栓塞,5枚手术夹闭,2枚颈内动脉可脱性球囊封阻术。结论:3D—DSA极大提高了脑血管造影检查的准确性和可靠性,为动脉瘤的介入治疗和手术夹闭提供了可靠保障,在临床诊疗中具有很高的应用价值。 相似文献
45.
Endocardial catheter ablation of ventricular tachycardia in patients with ventricular assist devices
Gopi Dandamudi MD Waqas S. Ghumman MD Mithilesh K. Das MD John M. Miller MD 《Heart rhythm》2007,4(9):1165-1169
BACKGROUND: The outcomes of patients with ventricular assist devices (VADs) who undergo catheter ablation for ventricular tachycardia (VT) have not been reported. OBJECTIVE: The purpose of this study was to assess the feasibility, safety, and efficacy of endocardial VT ablation in patients with VADs. METHODS: We retrospectively reviewed three cases at our institution where endocardial catheter ablation was performed in patients with VADs and incessant VT. RESULTS: Three patients with underlying cardiomyopathies and VADs underwent VT ablation for incessant VT refractory to multiple antiarrhythmic medications. In each case, VT was either eliminated or significantly ameliorated by catheter ablation. No procedure-related complications occurred. The hemodynamic stability afforded by the VAD played an important role in facilitating ablation in two of the cases. CONCLUSION: Catheter ablation for VT in VAD patients appears to be feasible, safe, and effective based on our initial experience. Several technical issues, such as decreases in ventricular volumes that can limit maneuverability of the ablation catheter and potential entrapment of the mapping catheter in the inflow cannula, need to be considered at the time of ablation. 相似文献
46.
Nicholas N Nissen Jeremy Korman Thomas Kleisli Kathy E Magliato 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(4):481-484
Evaluation and management of abdominal pathology in patients with ventricular assist devices is likely to become increasingly important as the utilization of these devices expands. Ventricular assist devices represent a class of intracorporeal or paracorporeal mechanical devices that augment cardiac output in patients with congestive heart failure. Patients with ventricular assist devices supporting both right and left ventricles (biventricular assist devices) are uniquely challenging to the general surgeon because these devices restrict direct access to the abdominal cavity and because of the perioperative implications of biventricular heart failure. We describe herein the first reported successful laparoscopic cholecystectomy in a patient with a paracorporeal biventricular assist device. Cholecystectomy was performed in this patient for acute cholecystitis that occurred while the patient was awaiting heart transplantation. Our results add weight to the small body of evidence that laparoscopy is well tolerated in ventricular assist devices patients. The unique aspects of the biventricular assist device patient make laparoscopic abdominal intervention particularly suitable in this patient population. 相似文献
47.
新一代低频电治疗仪的研制 总被引:10,自引:2,他引:8
本文介绍一种新型低频电脉冲治疗仪,采用新型单片机、程序控制和OTL功率放大器,产生变化有序的多种治疗脉冲波形模拟针灸治疗。电脉冲刺激器治疗仪可以用作减轻疼痛、放松肌肉、预防和减缓肌肉萎缩、增加局部血液循环等。 相似文献
48.
不同分娩方式妇女放置三种IUD的术时评价 总被引:2,自引:1,他引:1
目的:研究不同分娩方式妇女放置三种新型含铜宫内节育器(CulUD)的术时评价。方法:将观察对象按经阴道和经剖宫产的不同分娩方式分为两组,每组均随机放置CyneFix IN IUD、MCu功能性IUD和TCu380A IUD,记录两组放置不同种IUD的扩宫情况、置器疼痛反应和置器时间。结果:放置GyneFix IN IUD和TCu380A IUD在不同分娩方式组中扩宫率、痛觉评分、置器时间无显著差异(P>0.05)。放置MCu功能性IUD在剖宫产分娩组扩宫率为92.5%,显著高于阴道分娩组的33.3%(P<0.05);痛觉评分为8.62±0.82分,显著高于阴道分娩组(P<0.01);置器时间为(9.62±3.15)min,较另两种IUD置器时间显著延长(P<0.05)。结论:GyneFix IN IUD和TCu380A IUD置器术时扩宫率低、费时少,疼痛反应轻,不受分娩方式影响。 相似文献
49.
50.
Tadashi Nakazawa Yoshiyuki Takami Robert Benkowski Satoshi Ohtsubo Ohashi Yukio Eiki Tayama Goro Ohtsuka Yoshinari Niimi Julie Glueck Akinori Sueoka Helmut Schmallegger Heinrich Schima Ernst Wolner Yukihiko Nosé 《Artificial organs》1997,21(7):597-601
Abstract: To be able to salvage heart failure patients, the need for an economical permanent ventricular assist device is increasing. To meet this increasing demand, a miniaturized centrifugal blood pump has been developed as a permanently implantable device. The Gyro permanently implantable model (PI-601) incorporates a sealless design with a blood stagnation free structure. The pump impeller is magnetically coupled to the driver magnet in a sealless manner. This pump is atraumatic and antithrombogenic and incorporates a double pivot bearing system. A miniaturized actuator was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height and 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. Testing to date has included in vitro hydraulic performance and hemolysis. This pump can provide 5 L/min against a 110 mm Hg total pressure head at 2,000 rpm and 8 Limin against 150 mm Hg at 2,500 rpm. The normalized index of hemo-lysis (NIH) value of this pump was 0.0028 g/100 L at 5 Limin against 100 mm Hg. A preliminary anatomical study revealed the possibility of the implantability of 2 such systems in biventricular bypass at a preperitoneal location. This system is feasible for use as a permanently implantable biventricular assist device. 相似文献