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51.
Jamieson M. Bourque Eric J. Velazquez Robert H. Tuttle Linda K. Shaw Christopher M. O’Connor Salvador Borges-Neto 《Journal of nuclear cardiology》2007,14(2):165-173
Background Left ventricular ejection fraction (LVEF) is a significant predictor of morbidity and death. The nuclear summed rest score
(SRS) measures myocardial perfusion defects and provides prognostic information, but its effects on long-term outcomes are
not fully established. Moreover, information regarding the potential interaction between these 2 covariates is limited. The
purpose of this study was to determine whether the mortality risk associated with LVEF is the same across all values of SRS
in a population undergoing evaluation for ischemic heart disease.
Methods and Results We examined 3,187 patients who underwent cardiac catheterization and perfusion single photon emission computed tomography
imaging with a maximum follow-up of 8.1 years and median follow-up of 3.1 years. Cox proportional hazards modeling showed
that increasing nuclear SRS and decreasing LVEF were independently associated with a higher long-term mortality rate, with
a clinically significant interaction between them (P=.032). Patients with a normal LVEF and a high SRS (greater perfusion abnormality) have a prognosis similar to those with
a reduced LVEF.
Conclusions Resting perfusion studies provide prognostic information for long-term survival and significantly impact the interpretition
of mortality risk associated with changes in LVEF. Patient prognostication, risk stratification, and future research using
these variables should take this interaction into account.
Supported by a grant from the Tom & Lynn Royster Foundation. Durham, NC, and a National Institutes of Health Research Fellowship
Grant (T5 GM08679-04), Bethesda, Md. 相似文献
52.
目的探讨心肌静息显像联合冠状动脉造影及组织学检查在评价重组腺病毒-肝细胞生长因子(Ad—HGF)治疗猪实验性心肌梗死中的价值。方法低、中、高剂量Ad—HGF治疗组[Ad-HGF剂量依次为10^8,4×10^8,5×10^9空斑形成单位(PFU)/点;均分10点注射],生理盐水对照组及空白对照组小型猪各5头,分别于治疗前后行静息心肌显像及冠状动脉造影,并于治疗后行组织学检查。结果空白对照组及生理盐水对照组治疗前后心肌灌注及Rentrop评分无明显变化。各Ad-HGF治疗组治疗后心肌灌注及Rentrop评分较治疗前改善,低、中、高剂量组治疗前后冠状动脉左回旋支(LCX)供血节段得分分别为7.8±1.3和16.4±1.1(低),8.2±1.6和17.6±0.9(中),8.4±1.5和19.0±0.7(高);各组治疗前后LCX供血区域Rentrop评分分别为0.80±0.16和1.66±0.15(低),0.94±0.11和2.16±0.11](中),0.90±0.22和2.22±0.19(高)。3组治疗前后数据比较差异均有统计学意义(P〈0.01)。各Ad-HGF治疗组及空白对照组治疗后血管数量明显多于生理盐水对照组。结论用心肌静息显像联合冠状动脉造影及组织学检查评价Ad-HGF治疗猪心肌梗死的疗效有价值。 相似文献
53.
外科手术对心肌缺血的血运重建是目前治疗心肌缺血性疾病的重要手段之一。术中准确判断心肌缺血范围及程度和严密监测心脏停跳后心肌细胞损伤是否加重,对于血运重建的准确性,更好地实施心肌保护及对手术疗效的评估和术后处理方案的拟定有着重要意义。因此,如何在术中判断心肌缺血的损伤程度和范围具有极为重要的实验研究意义与临床现实意义。光学相干层析成像作为一种新颖的成像技术,能对活体组织内部微小结构进行实时、在体、高分辨率断层成像。 相似文献
54.
急性心肌梗死患者J波的临床研究 总被引:3,自引:0,他引:3
目的 研究心电图有 J波的急性心肌梗死 ( AMI)患者的临床情况。方法 选择住院的急性心肌梗死患者 10 2例 ,心电图有 J波者 5 0例为研究组 ,心电图无 J波者 5 2例为对照组 ,比较两组临床情况。结果 心电图有 J波组比心电图无 J波组发生胸闷 ( 3 0 /5 0∶ 2 0 /5 2 ,P<0 .0 5 )、前壁心肌梗死 ( 2 8/5 0∶ 18/5 2 ,P<0 .0 5 )、合并糖尿病 ( 14/5 0∶ 4/5 2 ,P<0 .0 5 )、超声心动图检查发生舒张功能减低 ( 2 4/5 0∶ 14/5 2 ,P<0 .0 5 )、心电图检查发现室性心动过速 ( 11/5 0∶ 1/5 1,P<0 .0 5 )者多。结论 心电图有 J波者比心电图无 J波者临床情况差 ,易于发生严重心律失常 相似文献
55.
F. Strik 《Documenta ophthalmologica. Advances in ophthalmology》1988,69(1):51-71
For an adequate assessment of both the ophthalmological and the neurological consequences of carotid obstruction measurement of the blood pressure in the carotid flow area is essential.To this end there are two objective, registrating methods available at the moment: OPG-Gee and OODG-Ulrich. A comparative study was made into the basic principles, calibration curves and application methods of these systems. By both methods the systolic retinal - and ciliary - as well as the diastolic ocular blood pressure can be measured. OODG is more exact for the differentiation and measurement of the two systolic blood pressures. OPG-Gee, however, offers the unique additional possibility of a judgement on the systolic blood pressure in the carotid siphon without, however, taking into acount a (difference in) pre-existing intraocular pressure. Our own investigation shows that in order to obtain a correct assessment of the carotico-brachial relation both blood pressures should be measured simultaneously. The results of the graphic analysis of the curves are compared to those by Ulrich. For the diagnosis of carotid obstructions this analysis of the shape had no advantages over the determination of the pressure values.Finally, a survey is given of possible applications of OPG and OODG in various other syndromes. 相似文献
56.
Giuseppe Giuffre’ Vincenzo Schifano Maria Vadala’ 《Documenta ophthalmologica. Advances in ophthalmology》1995,91(3):255-263
We report on a case of idiopathic uveal effusion syndrome complicated by AION. To our knowledge such an association hasn't been previously described. We suggest that scleral thickening caused obstruction of vortex veins followed by uveal effusion and compression of posterior ciliary arteries within their intrascleral tract, leading to AION. Nevertheless it can't be excluded that AION was the result of mechanical compression on ciliary vessels of optic disc by choroidal detachment. 相似文献
57.
Nitrate administration to enhance the detection of myocardial viability by technetium-99m tetrofosmin single-photon emission tomography 总被引:3,自引:1,他引:2
Albert Flotats Ignasi Carrió Montserrat Estorch Lluís Bernà Ana M. Catafau Carina Mart Manel Ballester 《European journal of nuclear medicine and molecular imaging》1997,24(7):767-773
A comparison was performed between technetium-99m tetrofosmin myocardial perfusion tomography at baseline and after nitrate administration, using a 2-day protocol, and rest-reinjection thallium-201 single-photon emission tomography (SPET) studies in order to assess whether nitrates enhance the detection of viable myocardium with99mTc-tetrofosmin. Fifteen patients with coronary artery disease, previous myocardial infarction and a left ventricular ejection fraction <40% underwent201T1 rest-injection and99mTc-tetrofosmin. baseline-postnitroglycerin (0.4 mg sublingually) SPET studies, within 48 h. Tomograms based on the three spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake >50% of peak activity on baseline studies or after reversibility. The percentage of peak activity of99mTc-tetrofosmin at baseline correlated with that of 201T1 (r=0.82,P <0.001). On baseline99mTc-tetrofosmin studies, 73 of the 225 segments that were analysed had <50% of peal. activity. Fifteen percent of these segments showed reversibility after nitrate administration, with an increase in99mTc-tetrofosmin uptake from 40%±9% to 57%±9% of peak activity (P=0.003). All reversible segments after nitrate administration had viability criteria on201Tl studies, but 20 segments that were non-viable on99mTc-tetrofosmin. studies were viable on201Tl studies. Using a threshold value of >40% of peak activity, only seven segments remained non-viable on99mTc-tetrofosmin studies. Overall agreement between99mTc-tetrofosmin with nitrates and201Tl-reinjection regarding the presence of myocardial viability was 90%. Detection of myocardial viability with99mTc-tetrofosmin. was enhanced after nitrate administration, correlating with viability criteria observed on thallium studies. 相似文献
58.
急性心肌梗死静脉溶栓后cTnT浓度比值对判断冠脉再通的价值 总被引:1,自引:0,他引:1
目的 探讨血清心肌肌钙蛋白T(cTnT) 3h 2h的浓度比值对急性心肌梗死 (AMI)溶栓后判定冠状动脉再通的价值。方法 采用ELISA法动态检测了 5 7例接受尿激酶静脉溶栓治疗的AMI患者和 31例正常健康对照血清cTnT ,CK MB及CK水平 ,并计算溶栓后 3h与 2h血清cTnT浓度比值。结果 ①cTnT释放呈现两种特征 ,再通组呈双峰型 ,未通组呈单峰型 ,且再通组后期峰值较未通组峰值低 (P <0 .0 1)。②cTnT浓度 3h 2h比值再通组明显高于未通组 (P <0 .0 1) ,以该比值 >1.4 8作为判定再通的标准 ,其对判定冠状动脉再通的敏感性、特异性、预测值分别为 83.3% ,90 .5 % ,93.8%。与峰值时间判定冠脉再通比较差异无显著性 (P >0 .0 5 )。结论 cTnT的动态检测可有效地判定对AMI溶栓后再通与否 ,特别是溶栓后 3h 2h浓度比值 >1.4 8可作为早期判定冠脉再通的标准 ,且具有迅速、省时等优点 ,值得推广应用 相似文献
59.
Myocardial protection in adult cardiac surgery: current options and future challenges 总被引:3,自引:0,他引:3
Francesco Nicolini Cesare Beghi Claudio Muscari Andrea Agostinelli Alessandro Maria Budillon Igino Spaggiari Tiziano Gherli 《European journal of cardio-thoracic surgery》2003,24(6):986-993
Current techniques of myocardial protection are evolving with the use of less conventional modalities of cardioplegia and have reduced the morbidity and mortality of cardiac operations. Blood cardioplegic solutions appear superior to cold cardioplegia in terms of myocardial protection and adjuncts as glutamate/aspartate enhancement, antioxidant supplementation, nitric oxide donors and maintenance of calcium homeostasis seem effective. In the near future, further experimental and clinical investigations about pharmacological preconditioning, sodium–hydrogen exchangers inhibition and gene therapy need to be addressed to well define their potential role in the improvement of current techniques of myocardial protection that are suboptimal in high-risk clinical settings. 相似文献
60.
缺血性脑血管病与颈动脉粥样硬化及其危险因素的关系 总被引:17,自引:0,他引:17
目的探讨缺血性脑血管病(ICVD)与颈动脉粥样硬化及其危险因素的关系。方法对186例ICVD患者与194例非脑血管病患者和正常体检者(对照组)行颈部血管超声检查和血液生化检查;比较两组间的颈动脉硬化程度及脑卒中危险因素的差异。结果ICVD组年龄[(69±7)岁]和患有高血压(66.1%)、糖尿病(53.4%)、代谢综合征患者(44.6%)的比率非常明显高于对照组[(61±5)岁、48.8%、15.2%、12.9%](均P<0.001)。ICVD组颈动脉粥样硬化分级计分≥2分(斑块发生率)、≥3分(血管狭窄发生率)分别为69.3%、20.4%,明显高于对照组的33.5%和5.1%(均P<0.05)。结论颈动脉粥样硬化是ICVD的危险因素之一;各种危险因素的聚集对ICVD的发生起重要作用。 相似文献