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71.
Resümee Schwerwiegende gastroduodenale Erkrankungen sind bei fast der Hälfte aller Patienten, die sich einer Operation am offenen Herzen unterziehen müssen, auch bei Fehlen von Symptomen nachweisbar. Das erhebliche Überwiegen von Magenläsionen spricht dafür, daß die arteriosklerotisch bedingte Perfusionsminderung der Schleimhaut die entscheidende Ursache hierfür ist. Routinemäßige präoperative Ösophago-Gastro-Duodenoskopien können die nicht unerhebliche durch gastrointestinale Komplikationen bedingte postoperative Mortalität senken helfen.
Pathological changes in the upper gastrointestinal tract in patients awaiting open heart surgery
Summary While waiting for open heart surgery, in 153 patients (104 male, 49 female, 22–76 years of age) without gastrointestinal symptoms and/or history esophago-gastro-duodenoscopy was performed. 124 patients suffered from coronary heart disease, 29 from valvular defect, aneurysm of the sinus of Valsalva or tumor of the heart.In 47.1% endoscopy revealed serious abnormal findings: in 16.3% gastric ulcer, in 20.9% erosive gastritis, duodenal ulcer and erosive duodenitis in 5.2%, respectively, 1 case of gastric carcinoma, 2 of large polyps and 3 of reflux esophagitis of higher degree (totally 3.9%).In patients with coronary artery disease, the relation of erosive and ulcerous gastric lesions as compared with those of duodenal origin was 41, in patients with other cardiac diseases it was 21, respectively (p<0,001).Compared with a normal population, the incidence of pathological gastric findings was 54-fold higher in our patients, and 1.7-fold concerning duodenal lesions, respectively (p<0.001).51 patients on acethylsalicylic acid (160 mg/ die) showed pathologic findings in 41.2%, and 96 patients without ulcer-inducing therapy in 51%. Thus, low-dose Aspirin does not seem to have serious gastric side effects.The results of the study stress the necessity of routinely performed endoscopy of the upper gastrointestinal tract in patients awaiting open heart surgery. This will lead to a lower incidence of serious gastrointestinal complications postoperatively, which are known to have a high mortality.

Abkürzungen ASS Azetylsalizylsäure - J. Jahre - GI-Trakt Gastrointestinaltrakt  相似文献   
72.
目的:探讨ATP敏感性钾通道(KATP通道)开放剂KRN2391(KRN)对离体大鼠心功能及心肌梗死范围的影响。方法:用Langendorff装置,观察不同浓度KRN对冠脉灌流量及左心室压力的影响。应用离体大鼠双冠脉分别灌注芊45min缺血及2h再灌注,观察药物对心肌梗死面积的影响。结果:KRN在达到1umol/L浓度后冠脉灌流量明显增加,达20umol/L时左室收缩压明显下降,用1umol/LK  相似文献   
73.
[1]Richardson CP, Mckenna RM, Bristow CM, et al.Report of the 1995 Word Health Organization/International Society and Federation of Cardiology Task Force on the definition and classification of cardiomyopathies. Circulation, 1996,93: 841 [2]Barr CS, Naas A, Freeman M, et al. QT dispersion and sudden unexpected death in chronic heart failure. Lancet, 1994,343:327 [3]Martin AB, Garson A, Perry JC, et al. Prolonged QT interval in hypertropic and dilated cardiomyopathy in children. Am Heart J, 1994,127(1):64 [4]Pye M, Quinn AC, Cobble SM. QT dispersion: a non-invasive marker of susceptibility to arrhythmia in patients with sustained ventricular arrhythmias?Br Heart J, 1994,71(5):51 [5]Berger RD, Kasper EK, Baughman KL, et al. Beat to beat QT interval variability: novel evidence for repolarization lability in ischemic and non ischemic dilated cardiomyopathy. Circulation, 1997, 96 (5):1557 [6]Wolfram G, Ulrike S, Volker M, et al. QT dispersion and arrhythmic events in idiopathic dilated cardiomyopathy. Am J Cardiol, 1997,78: 458 [7]Fei L, Goldman JH, Prasal K, et al. QT dispersion and RR variations on 12-lead ECGs in patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy. Eur Heart J, 1996,17: 258 [8]Pan YZ, Guo NS, Xing ZF, et al. The relation between QT dispersion and ventricular arrhythmia of dilated cardiomyopathy. Chin J Inter Medi, 1996,35(11):73 [9]Galinier M, Vialette JC, Fourcade J, et al. QT interval dispersion as a predictor of arrhythmic events in congestive heart failure. Importance of aetiology. Eur Heart J, 1998,19(7) :1054  相似文献   
74.
不同实体瘤体外药敏试验的可行性研究   总被引:1,自引:0,他引:1  
目的:研究体外药敏试验用于不同原代培养肿瘤细胞的可行性,方法:采用MTT比色分析法,结果:非小细胞肺癌,食管癌,贲门癌对乐铂均较敏感,不同病理类型和同一类型的不同个体对乐铂的敏感性差异较大,且其抑制作 病理类型无密切关系。结论:MTTI地操作简便,快捷,敏感,可应用于实体瘤临床个体化的药敏检测。  相似文献   
75.
多普勒超声心动图评估左心室舒张末压的研究   总被引:1,自引:0,他引:1  
目的探讨多普勒超声心动图评估左室舒张末压的有效方法与指标。方法对68例病人采用左心导管测压及经胸多普勒超声心动图检测。结果对比研究显示,联合肺静脉与二尖瓣血流频谱分析优于二尖瓣血流频谱分析,肺静脉A峰和二尖瓣A峰时限差值(PAd-Ad)与左室舒张末压实测值呈最佳相关性(r=0.72,P<0.01)。结论认为应用多普勒超声心动图测定PAd与Ad,并以其差值估测左室舒张末压,是一项简便、可靠的无创性评估左室舒张末压的方法。PAd-Ad≥0可作为临床判断左室舒张末压增高[≥2.0kPa(15mmHg)]的一项半定量指标。  相似文献   
76.
77.
Summary The goal of this study was to elucidate the causes why the proarrhythmic activity of sodium channel blocking drugs is enhanced during the post-infarction period. Therefore, we studied the effects of a reduction in sodium conductance on the action potential duration and its dispersion in a simulated array of 1600 ventricular myocytes. Cardiac tissue is known to possess anisotropic properties with regard to the intercellular electrical resistance (R). Infarction as well as aging causes deposition of collagen in the cardiac tissue, thereby inducing zones of high electrical resistance leading to a non-uniform anisotropy (Spach et al., Circ Res 62811, 1988). For our study an array of 40*40 ventricular myocytes was simulated using Beeler-Reuter-algorithms. Physical tissue properties were assumed to be either a) uniform anisotropic (i.e., all longitudinal R=5000 cm, all transversal R=20000 cm; UA) or b) non-uniform anisotropic (i.e., transversal R for the inner 10*10 cells was set to 1010 cm; NUA). Mean action potential duration (APD) was increased under UA (287 ms, dispersion: 0,8 ms) when compared to NUA (285 ms, disp.: 3,2 ms). Assuming a 25% decrease in sodium conductance, we found the total activation time (TAT) to be increased (from 99 to 139 ms), indicating slowing of conduction, APD to be shortened (from 287 to 259 ms), and the APD-dispersion to be increased (from 0.8 to 29 ms) in UA. These changes were more pronounced in the case of NUA: increase in TAT from 103 to 150 ms, APD-shortening from 285 to 214 ms and a marked increase in APD-Dispersion from 3.2 to 53 ms). From these results it is concluded that a) the effects of a reduced sodium conductance are more pronounced in NUA tissue, and b) that the resulting increase in dispersion may provoke arrhythmia by local differences in APD.This may be one of the mechanisms underlying the increased proarrhythmic risk of class I antiarrhythmic drugs in the postinfarction period.  相似文献   
78.
Summary Effective treatment of hypertension in the elderly requires an understanding of both the progressive course of the disease and the impact of aging on the cardiovascular system, including physiological, genetic, lifestyle, and environmental factors. Review of the literature that has attempted to define the impact of an aging process on cardiovascular structure and function reveals a diversity of findings and interpretations. However, in general, normotensive elderly subjects exhibit the heart and vascular characteristics of muted hypertension, including many features of younger hypertensive patients: cardiac hypertrophy, diminution in resting left ventricular early diastolic filling rate, increased arterial stiffness and aortic impedance, diminution in the baroreceptor reflex, a diminished response to catecholamines and diminished renal blood flow, and an increase in peripheral vascular resistance (PVR). Treatment of elderly hypertensives is more challenging because of the greater likelihood of the presence of concomitant diseases, most importantly, coronary and peripheral atherosclerosis, renal dysfunction, and diabetes mellitus. Isolated systolic hypertension (ISH), the most common form of hypertension in the elderly, has also been clearly shown to be an important predictor of cardiovascular morbidity and mortality, including coronary artery disease, congestive heart failure, and stroke. Treatment of ISH has been shown to lower systolic pressure safely and effectively in the elderly. By reducing PVR, and possibly the arterial stiffness, and thus the early reflected pulse waves, vasodilators, including calcium antagonists, may lower these three components of arterial impedance, and hence lower the arterial load on the heart. The cardiac hypertrophy and reduced left ventricular filling rate associated with hypertension in older individuals can also be ameliorated, to some extent, by calcium channel blockers.Proceedings of a symposium held in Atlanta, Georgia on March 2, 1991.  相似文献   
79.
Summary The negative inotropic effect of adenosine (1–100 M) was abolished in isolated guinea-pig atria obtained from pertussis toxin-pretreated guinea pigs electrically driven at 4 Hz. However, the inhibitory effect of the same concentrations of adenosine on the cardiac response to stimulation of non-adrenergic non-cholinergic (NANC), capsaicin-sensitive sensory nerves, was not modified by the toxin.These results suggest that, while pertussis toxin-sensitive G proteins are involved in the negative inotropic effect of adenosine, they do not mediate the inhibitory effect of adenosine on cardiac NANC neurotransmission.  相似文献   
80.
The abdominal left ventricular assist device (ALVAD) is an order of magnitude more effective than conventional intra-aortic balloon pumping (IABP) in unloading and providing circulatory support to the failing left ventricle. This is a report of a unique case which demonstrates that in the absence of pulmonary vascular obstruction or constriction, the ALVAD can substitute for both left and right heart function. A 21-year-old patient with a congenital bicuspid aortic valve developed acute valvular endocarditis which rapidly progressed to congestive heart failure. An operation was undertaken, the mitral and aortic valves were excised and replaced by porcine heterografts, and a fistula from the right sinus of Valsalva to the right ventricle was closed. When coronary circulation was restored, irreversible ischemic contracture of the left ventricle, or "stone heart" syndrome, developed and emergency ALVAD or partial artificial heart implantation was effected. This device functioned as a total artificial heart for nearly six days, while a donor heart was sought. The patient then underwent removal of the ALVAD and cardiac and renal allografting. The transplanted heart functioned well, but the patient expired fifteen days later from gram-negative sepsis.  相似文献   
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