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31.
Mustafa Hassan Kaki M. York Haihong Li Qin Li David S. Sheps 《Journal of nuclear cardiology》2007,14(3):308-313
Background Reduced left ventricular ejection fraction (LVEF) is a risk factor for poor outcomes in patients with coronary artery disease
(CAD). Mental stress-induced myocardial ischemia (MSIMI) also identifies a subset of CAD patients at increased risk for future
cardiovascular events. Susceptibility to MSIMI in patients with CAD and reduced LVEF is unknown.
Methods and Results We enrolled 182 patients (67 women) with a mean age of 64 years and a documented history of CAD in this study. Baseline resting
ejection fraction was determined by use of technetium 99m sestamibi gated single photon emission computed tomography. Abnormal
LVEF was defined as less than 45% for men and less than 50% for women (based on published norms for our software [Cedars-Sinai
Medical Center]). All participants underwent mental stress testing with a public speaking task. Rest/stress myocardial perfusion
single photon emission computed tomography was performed via conventional methodology. Images were visually compared for number
and severity of perfusion defects by use of a scoring method from 0 to 4. A summed difference score was calculated as the
difference between summed stress and rest scores. A score of greater than 3 was considered abnormal. MSIMI developed in 19%
of patients with normal LVEF and 31% of those with reduced LVEF. There is no statistically significant difference between
the two groups (P=.11).
Conclusions CAD patients with left ventricular dysfunction are equally susceptible to MSIMI as those with normal LVEF.
This study was supported by grants HL 070265 and HL 072059 from the National Heart. Lung, and Blood Institute. This material
is also the result of work supported by resources and with the use of facilities at the Department of Veterans. Affairs Medical
Center, Gainesville, Fla. 相似文献
32.
主动脉内球囊反搏在低射血分数患者非体外循环冠状动脉旁路移植术中应用的必要性探讨 总被引:4,自引:0,他引:4
目的探讨对低射血分数患者施行非体外循环冠状动脉旁路移植术(off-pump coronary artery bypass grafting, OPCAB)预防性应用主动脉内球囊反搏(intraaortic balloon pump, IABP)辅助的必要性. 方法 2001 年1 月~2004年10月对64例低射血分数(LVEF≤40%)施行OPCAB,将64例分为2组:术前或术中预防性应用IABP辅助者列为IABP组,共19例;未应用IABP者列为对照组,共45例. 结果 IABP组与对照组在术后并发症手术死亡、脑血管意外、肾功能衰竭衰血滤、围手术期心肌梗死等方面无显著差异(χ2=0.000,P=1.000).IABP组术后需要延长呼吸机带机时间(超过24 h)的比例显著高于对照组(IABP组8例,对照组3例; χ2=9.429,P=0.002);IABP组术后监护时间延长(超过48 h)的比例显著高于对照组(IABP组14例,对照组19例; χ2=4.110,P=0.043). 结论在无IABP辅助的情况下,为低射血分数患者实施OPCAB手术是可行的. 相似文献
33.
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
34.
Suppiah Balachandran Stuart Eason Lynn McGuire Suzanne Bernard Charles Boyd 《European journal of nuclear medicine and molecular imaging》1986,12(2):69-71
Summary In order to measure ejection fractions (EFs) from nuclear ventriculograms, we devised a semi-automated edge-detection technique based on a combination of inverse Fourier analysis and second-derivative techniques. Initial clinical studies showed that, for the left ventricle, our method gives EF values statistically identical with those obtained using a conventional isocontour technique. For the right ventricle, however, the values obtained using the two methods were somewhat more at variance. Despite requiring a longer processing time, the results obtained with our method are reproducible because less operator intervention is necessary. 相似文献
35.
Ajit K. Shah Richard C. Brundage Kathleen D. Lake Ronald J. Sawchuk 《Biopharmaceutics & drug disposition》1995,16(1):59-70
We estimated the free fraction (fu) of cyclosporine (CyA) in the plasma from concentrations of CyA in urine (Cu) and plasma (Cp), urine flow rate (UF), and glomerular filtration rate in rabbits and in heart transplant patients. Following intravenous administration of CyA (5–30 mg kg?1) in ten NZW rabbits and oral administration of CyA (4.8–12.1 mg kg?1) in nine heart transplant patients, CyA concentrations in urine and plasma were measured by HPLC. The ratios of Cu to Cp and UF data were fitted to a physiological model of renal clearance using NONMEM. The free fraction of cyclosporine in the rabbits and the heart transplant patients was 0.0122 and 0.14, respectively. Because of the relatively low permeability of CyA across the tubular epithelium, no apparent equilibrium between Cu and Cp at any urine flow rate was reached and, therefore, the Cu to Cp ratio will not be equal to fu. 相似文献
36.
An immunohistochemical study of melanocytic tumours using 19A2, a monoclonal antibody against proliferating cell nuclear antigen (PCNA/cyclin), was performed on tissues routinely processed with formalin fixation and paraffin embedding. In normal skin, keratinocytes of the suprabasal region in epidermis, the papillae and outer root sheath of hair follicles and the basal cells lining the lobules of sebaceous glands were stained in the nucleus. Other skin components, including basal and follicular melanocytes, did not demonstrate nuclear labelling. In addition, expression of PCNA/cyclin in keratinocytes was higher in sun-exposed skin compared with unexposed skin. In melanocytic lesions, PCNA/cyclin positive tumour cells increased in number and staining intensity according to the following progression: common melanocytic naevi; dysplastic naevi; primary melanomas; and metastatic melanomas. Expression of PCNA/cyclin, therefore, provides a useful marker for proliferation and tumour progression in skin. 相似文献
37.
粪便隐血试验是检测消化道微量出血的重要手段。本文用三种隐血试验:血红蛋白定量试验(HQT)、反向间接血球凝集试验(RPHA)和联苯胺试验(BT)对不同消化道疾病患者的粪便进行检测。结果表明隐血的检出用HQT和RPHA较BT更为特异和敏感。 相似文献
38.
二维超声心动图对高原婴幼儿右室射血分数的估测 总被引:2,自引:0,他引:2
目的:将二维超声测量右室射血分数(RVEF)的方法应用于临床。方法:用心尖四腔观单平面面积-长度法测量43例高原正常婴幼儿RVEF,并与40例患右室扩张肥厚型心肌病(RVDCHM)婴幼儿进行了比较。结果:健康组RVEF均值为58.20%,标准差为7.24%;患儿组均值为36.10%,标准差为7.01%,两组测量的RVEF有非常显著差异(P<0.001)。结论:心尖四腔观单平面面积-长度法测量RVEF可作为估测右室收缩功能的简单可靠的方法。 相似文献
39.
胸腺免疫抑制组分的抗变态反应作用 总被引:1,自引:0,他引:1
整体实验表明,胸腺免疫抑制组分肌内注射1wk对大鼠被动皮肤过敏反应(8、20、50和125mg·kg-1)兔Arthus反应(4和12mg·kg-1)均有明显的抑制作用。体外实验表明,该药能抑制致敏豚鼠离体回肠平滑肌的过敏性收缩,IC50为446.7mg·L-1。上述结果表明,胸腺免疫抑制组分有抗Ⅰ和Ⅲ型变态反应的作用。 相似文献
40.
Robert H. Smallwood George W. Mihaly Richard A. Smallwood Denis J. Morgan 《Journal of pharmacokinetics and pharmacodynamics》1988,16(5):529-542
For substances eliminated from blood by the liver, the effect of a change in unbound fraction of drug (fu
b
)on steady state total (C
b
)and unbound (Cu
b
)blood concentrations has hitherto only been considered for the two limiting cases, i.e., at the upper and lower extremes of hepatic intrinsic clearance (CL
int
).For a substance of very low CL
int
,if fu
b
changes, C
t
will change and Cu
b
will remain constant, whereas if CL
int
isvery high, Cu
b
will change and C
b
will remain constant.The present study defines the effects of a change in fu
b
on C
b
and Cu
b
over the whole CL
int
range. Computer simulations were undertaken which predicted that, for a given change in fu
b
,absolute and relative changes in C
b
would decreasenonlinearly with increasing CL
int, twhile the relative change in Cu
b would increasewith CL
int
.The absolute change in Cub
would be independent of CL
int
.Significant changes in Cb and Cu
b would be observed at intermediate values of CL
int not just at the high and low extremes. These theoretical predictions were investigated experimentally in the isolated perfused rat liver by examining the effects of a change in fu
b of sodium taurocholate a substance with intermediate CL
int
(such that at fu
b
=0.27,hepatic extraction ratio=0.71) induced by concurrent administration of sodium oleate. Sodium 24-
14
C-taurocholate (specific activity 52 Ci/mmol) was infused into the reservoir in a recycling system at 30 mol/hr for 105 min (n=6). At 45 min a bolus dose of sodium oleate (50 mmol) was administered to the reservoir, followed by a constant infusion of 143 mmol/hr for 1 hr. Following the administration of oleate, taurocholate fu
b fell promptly by 55% (0.27–0.12). There was a relative increase of taurocholate C
b of 22.7% and a relative decrease in Cu
b of 45.4%, in accordance with the simulations (p<0.05). We conclude that important changes in unbound steady-state concentration, the pharmacologically active moiety, can occur upon changes in unbound fraction with compounds of intermediate hepatic intrinsic clearance.This study was supported by the National Health and Medical Research Council of Australia. 相似文献