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2.
Reliable discrimination between sinus tachycardia (ST) and pathologic tachycardia has been a major problem for automatic implantable antitachycardia devices. In patients whose sinus response to activity is as rapid or faster than their pathologic tachycardia (rate crossover), these unsophisticated devices deliver the programmed tachycardia response to either the pathologic or sinus tachycardia. Over a one-year period, 50 Intermedics Intertach Model 262–12 antitachycardia pulse generators were implanted to evaluate the specificity of a new group of tachycardia recognition algorithms. Patients were subjected to exercise testing and noninvasive programmed stimulation to demonstrate the efficacy of this new approach. The five recognition algorithms tested were various combinations of the following criteria: high rate HR), sudden onset (SO), rate stability (RS), and sustained high rate (SHR). False positive rates (tachycardia response inappropriately triggered by ST) were as follows: HR (93%); HR + SO (3%); HR + RS (63%); HR + (RS or SHR) (87%); HR + HS + SO (8%). Pair-wise significance testing between HR only and HR + SO (p < 0.001), HR + RS (p = 0.01) and HR + SO + RS (p < 0.001), demonstrated a significant reduction in the rate of false positives through the use of the sudden onset and rate stability criteria in concert with the standard high rate criterion. 相似文献
3.
应用同种动脉治疗主动脉根部病变 总被引:4,自引:0,他引:4
报告5例采用同种动脉(HAV)治疗5例主动脉根部病变(主动脉瓣狭窄1例,关闭不全4例)。男3例,女2例;年龄13~47岁。病因为细菌性心内膜炎2例(包括先天主动脉瓣二瓣化畸型1例),Marfan综合征2例,风湿性主动脉瓣关闭不全1例。术中采用同种主动脉全根置换3例(Bentall手术),其中1例用HAV上的二尖瓣前叶加宽主动脉瓣环(Manouguian手术),余2例用自体肺动脉移置主动脉根部,另取同种肺动脉做原位移置(Ross手术)。结果死亡1冽,4例存活,且无并发症发生。术后超声心动图提示主动脉根部良好,无主动脉瓣反流。随访2.5~3.5年疗效满意。 相似文献
4.
MICHAL J. KANTOCH ROXANE McKAY MICHAEL J. TYRRELL 《Pacing and clinical electrophysiology : PACE》1993,16(9):1887-1891
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
5.
Automatic Implantable Cardioverter Defibrillator/Permanent Pacemaker Interaction: Loss of Pacemaker Capture Following AICD Discharge 总被引:1,自引:0,他引:1
MARVIN SLEPIAN JOSEPH H. LEVINE LEVI WATKINS Jr. JEFFREY BRINKER THOMAS GUARNIERI 《Pacing and clinical electrophysiology : PACE》1987,10(5):1194-1197
A 78-year-old man treated with amiodarone for recurrent ventricular tachycardia, had sequential placement of a bipolar VVI pacemaker and an automatic implantable cardioverter defibrillator (AICD). During defibrillation threshold testing, there was failure to capture of the pacer in the post-shock period. The time of failure to capture appeared energy-related: the greater the energy delivered, the longer the failure to capture. Careful attention will be necessary in constructing combined AICD/pacemaker units. 相似文献
6.
7.
Despite its theoretical advantages in terms of less invasive surgery, bi-unicompartmental knee replacement still represents
a controversial knee reconstructive procedure. Many orthopaedic surgeons are skeptical about this demanding procedure despite
the possibility of maximally preserving anatomy, with benefits for functional aspects such as gait, muscle activity and proprioception.
Presently, no results of bi-unicompartmental knee replacement have been reported in the literature, even if several surgeons
use it in selected cases. We present a retrospective analysis of our experience with this implant at a minimum follow-up of
36 months. At the latest follow-up, the mean Knee Society score was 80.58, the mean functional score was 83.5 and the mean
postoperative GIUM score was 78. No implant has been revised and all patients are satisfied with the outcome. We consider
bi-unicompartmental knee replacement to be a reasonable, less invasive option for the treatment of knee arthritis in selected
cases. 相似文献
8.
9.
[目的]探讨人工踝关节置换治疗踝关节病的疗效。[方法]对1999~2004年1月的18例患者包括骨性踝关节炎6例,创伤性踝关节炎9例,局限性距骨缺血坏死2例,踝关节融合后1例,均采用L ink STAR假体3构件套进行人工踝关节置换。18例中,男13例,女5例;平均年龄47.7岁(38~67)。[结果]随访平均3 a 9个月(1~5 a)。按Kofoed评价系统观察疗效,优(85~100)16例,良(75~84)2例,无可(70~74)和差(<70)。患足背屈平均8°(范围6°~12°),跖屈12°(范围8°~16°),背屈和跖屈平均16°(11°~23°)。并发症有切口皮缘坏死2例,无足内、外翻和影像学松动。[结论]人工踝关节置换是治疗和替代踝关节多种疾患疼痛和需要融合的良好方法。 相似文献
10.
微处理器控制的植入式心脏起搏器专用电路研制 总被引:2,自引:0,他引:2
金捷 《中国医疗器械信息》2003,9(5):11-13
介绍了一种基于微处理器的植入式心脏起搏器专用电路设计。该设计采用的技术路线和国外现有技术方案不同,它采用通用微处理器设计,降低了投资风险,缩短了开发周期.特别适合于我国这样的发展中国家。 相似文献