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1.
2.
D. Le Elizabeth Eric R. Powers Jian-Ping Bin Howard Leong-Poi N. Craig Goodman Sanjiv Kaul 《Journal of nuclear cardiology》2007,14(2):207-214
Background The mechanism by which transmyocardial revascularization (TMR) offers clinical benefit is controversial. We hypothesized that
TMR ameliorates ischemia by reversing paradoxical catecholamine-induced vasoconstriction.
Methods and Results Chronic ischemic cardiomyopathy was created in 11 dogs by placing ameroid constrictors on the proximal coronary arteries and
their major branches. Six weeks later, 35 channels were created percutaneously in the left circumflex artery region, with
the left anterior descending artery region serving as control. At rest, wall thickening and myocardial blood flow did not
change in the treated region, whereas they deteriorated in the control bed. Contractile and myocardial blood flow reserve
increased in the treated region but deteriorated in the control region. There was diminished iodine 123 metaiodobenzylguanidine
uptake and a significant reduction in noradrenergic nerves in the treated region compared with the control region, with a
corresponding reduction in tissue tyrosine hydroxylase activity.
Conclusions We conclude that the absence of a catecholamine-induced reduction in MBF reserve and contractile reserve in the TMR-treated
region with associated evidence of neuronal injury indicates that the relief of exercise-induced ischemia after TMR most likely
results from reversal of paradoxical catecholamine-induced vasoconstriction. These findings may have implications in selecting
patients who would benefit from TMR.
Supported in part by grants from the National Institutes of Health (R01-HL66034 and K-08-HL074290-01). Bethesda. Md. The radio-labeled
microspheres were provided by DuPont Pharmaceuticals, North Billerica. Mass, and the ultrasound equipment was supplied by
Philips. Andover, Mass. Dr Leong-Poi was the recipient of a Fellowship Training Grant from the Canadian Institute of Health
Research and the Heart and Stroke Foundation of Canada. 相似文献
3.
Cardiomyopathy: a late complication of hemolytic uremic syndrome 总被引:2,自引:0,他引:2
Amanda M. Walker Lee N. Benson Greg J. Wilson Gerald S. Arbus 《Pediatric nephrology (Berlin, Germany)》1997,11(2):221-222
This report describes a child who presented with classic hemolytic uremic syndrome (HUS) and 4 months later developed a life-threatening
but reversible cardiomyopathy with global cardiac dysfunction and a left ventricular ejection fraction of 14%. There was no
evidence of electrolyte abnormalities, anemia, hypertension, severe fluid overload, or viral infection. Endomyocardial biopsies
were consistent with a dilated cardiomyopathy. This paper highlights the importance of considering the diagnosis of associated
cardiomyopathy when presenting with late-onset edema following HUS.
Received February 12, 1996; received in revised form and accepted August 22, 1996 相似文献
4.
扩张型心肌病与β1 受体自身抗体关系初探 总被引:2,自引:1,他引:1
目的 探讨抗β1受体自身抗体与扩张型心肌病(DCM)之间的关系。方法 以人心脏β1受体细胞外第二环表位肽段作为抗原,应用酶联免疫吸附测定(ELISA)技术,检测28例DCM患者和32例正常人血清中β1受体的自身抗体。结果 DCM患者血清中有13例(46%)抗β1受体自身抗体阳性,正常人血清中有2例(6%),两组阳性率差异有显著性(P<0.01);DCM组自身抗体平均几何滴度为1:92,显著高于正常对照组1:20(P<0.01);DCM患者中自身抗体阳性者的抗体滴度在不同心功能间的分布差异有显著性(P<0.001)。结论 DCM患者存在着β1受体自身抗体且其滴度也明显高于正常对照组。 相似文献
5.
阿霉素可导致剂量累积性心肌细胞损伤。L-肉毒碱已确认能减轻心肌细胞形态学改变。本实验测定了心肌细胞线粒体膜流动性,目的是从生物化学角度观察L-肉毒碱对阿霉素性心肌损伤的作用。实验结果表明:阿霉素可引起线粒体膜流动性的明显改变。而补充外源肉毒碱可改善这种状态。 相似文献
6.
63例扩张型心肌病的长期随访分析 总被引:1,自引:1,他引:0
目的:评价扩张型心肌病的远期预后。方法:扩张型心肌病患者63例,给予强心、利尿、β受体阻滞剂、血管紧张素转化酶抑制剂及中药生脉(参麦)复方制剂治疗,定期随访,随访时间3~13年。随访项目包括:心功能改善情况、体力活动适应程度、院外服药治疗、再次入院次数,死亡,了解并登记死亡原因。结果:63例中随访3~5年16例,5~10年35例,10年以上12例,平均随访时间6.1年。随访期间死亡18例(病死率28.6%);存活45例,存活者患病时间2~15年,其中28例能从事一般正常劳动及工作(62.2%),生活可自理者10例(22.2%)。结论:由于治疗方案的改进,特别是中西医结合药物的应用,使扩张型心肌病患者的预后改善,平均存活时间延长,多数患者的生存质量提高。 相似文献
7.
G. J. van Ekeren A. M. Stadhouders J. A. M. Smeitink R. C. A. Sengers 《European journal of pediatrics》1993,152(3):255-259
The objectives of this study were to describe the course of two forms of an hereditary syndrome characterised by congenital cataract, mitochondrial myopathy of heart and skeletal muscle and lactic acidosis. We also sought to determine clinical, physicochemical and histopathological data which might allow early distinction between the two forms. We compared the ages at which clinical and physicochemical signs appeared in 16 patients. In 5 patients, enzyme-histochemical and ultrastructural data of skeletal muscle were available and muscle fibre composition analysed morphometrically. In any particular family only one form of the syndrome occurred. Amongst the patients who did not survive (range 14–34 years) 4 patients died in the neonatal period and 7 died at a median age of 23 years. The median age of the survivors was 19 years (range 15–42 years). Outflow obstruction of the left ventricle was noted in four deceased patients at variable times prior to death. The other deceased patients were not examined, but the cause of death was invariably heart failure. In none of the surviving patients was outflow obstruction noted. Enzyme-histochemical and ultrastructural findings were not specific for the course of the disease. In one biopsy, taken at the age of 3.5 months from a patient who survived, strong lipid accumulation was noted. Morphometric analysis showed proliferation of the mitochondria in muscle fibres, which increased during the course of the disease. 相似文献
8.
Michiko Kawaguchi Masaaki Techigawara Takako Ishihata Tsukasa Asakura Fujiko Saito Kazuhira Maehara Yukio Maruyama 《Heart and vessels》1997,12(6):267-274
Summary The pathogenesis of diabetic cardiomyopathy is unknown. The synergistic, or enhanced, effect of hypertension on pathological
changes in the heart of diabetic patients has been highly suspected. The purpose of this study was to evaluate the myocardial
changes related to diabetes mellitus with and without hypertension, using biopsy specimens. We examined the ultrastructural
changes in biopsy specimens of the endomyocardium obtained from 25 patients. They were divided into four groups: controls
without hypertension or diabetes mellitus (n=6), and patient with hypertension (n=3), diabetes mellitus (n=8), and diabetes with hypertension (n=8). The diabetic patients showed nearly normal or mildly depressed systolic left ventricular function. Ultrastructural pictures
were analyzed for thickening of the capillary basement membrane, presence of toluidine blue-positive materials (i.e., materials
showing metachromasia) in the myocytes, size of myocytes, and interstitial fibrosis. The thickening of the capillary basement
membrane, the accumulation of toluidine blue-positive materials, and interstitial fibrosis were all significantly greater
in the patients with diabetes mellitus compared to the control subjects. The myocytes tended to be small (cell atrophy) in
the diabetes group. Although these pathological changes in the heart were characteristic of diabetic patients, irrespective
of the presence or absence of hypertension, the presence of hypertension increased the pathological changes of myocardial
cells as well as abnormality in the capillary vessels in patients with diabetes mellitus. Alterations in the myocardial cells
and capillaries, caused by diabetes mellitus, may lead to myocardial cell injury and interstitial fibrosis and, ultimately,
to ventricular systolic and diastolic dysfunction, especially when the diabetes is accompanied by hypertension. 相似文献
9.
急性心肌梗塞错误溶栓治疗12例分析 总被引:1,自引:0,他引:1
自1993年12月至1995年8月,对155例急性心肌梗塞(AMI)病人进行溶栓治疗,12例发生误溶(7.7%)。其中早期复极综合征4例,室壁瘤2例,心肌炎1例,心肌病1例,完全性左束支阻滞1例,间歇性左前分支阻滞互例,其它2例。本文分析了误溶病例与AMI的鉴别要点,并提出了减少误溶,提高诊疗水平的措施。 相似文献
10.
背景 血栓栓塞(TE)事件是肥厚型心肌病(HCM)的重要并发症。目前针对HCM患者TE事件的风险预测,仅国外学者构建了两个模型:HCM Risk-CVA及French HCM score,然而,现有研究发现HCM Risk-CVA模型对于中国HCM患者的临床价值较为有限。目的 本研究拟构建适合中国HCM患者的TE事件风险预测模型。方法本研究系回顾性队列研究,收集2010—2018年在四川大学华西医院就诊的537例HCM患者的病例资料。本研究通过电话随访或电子病历系统查询患者就诊记录,每6~12个月随访1次,直至出现终点事件或死亡或研究拟定的评估日期(2019-12-31),终点事件定义为复合性TE事件。采用单因素和多因素Cox回归分析构建风险预测模型,并使用自助重抽样的方法进行内部验证。结果 537例患者中,24例患者有不同程度的数据缺失,最终纳入513例患者。中位随访时间为4.2(1.3,6.2)年,随访过程中42例(8.18%)发生TE事件,年发病率为2.10%[95%CI(1.47%,2.73%)]。根据多因素Cox回归模型构建TE事件风险预测模型,最终纳入年龄、既往TE事件、心... 相似文献