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排序方式: 共有2418条查询结果,搜索用时 15 毫秒
1.
Saskia L.M.A. Beeres MD Katja Zeppenfeld MD Jeroen J. Bax MD Petra Dibbets-Schneider Marcel P.M. Stokkel MD Willem E. Fibbe MD Ernst E. van der Wall MD Douwe E. Atsma MD Martin J. Schalij MD 《Heart rhythm》2007,4(3):257-265
BACKGROUND: Bone marrow cell injection has been introduced to treat patients with ischemic heart disease. However, focal application of bone marrow cells may generate an arrhythmogenic substrate. OBJECTIVES: To assess the electrophysiological and arrhythmogenic effects of intramyocardial bone marrow cell injection in patients with chronic myocardial ischemia. METHODS: Bone marrow was aspirated in 20 patients (65+/-11 years, 19 male) with drug-refractory angina and myocardial ischemia. Electroanatomical mapping (NOGA, Biosense-Webster, Waterloo, Belgium) was performed during mononuclear cell isolation. Areas for cell injection were selected based on the localization of ischemia on SPECT. These areas were mapped in detail to evaluate local bipolar electrogram duration, amplitude and fragmentation. Mononuclear cells were injected in the ischemic area with the NOGA system. SPECT and electroanatomical mapping were repeated at 3 months. Holter monitoring was repeated at 3 and 6 months. RESULTS: SPECT revealed a decrease in the number of segments with ischemia (3.5+/-2.5 vs. 1.1+/-1.0 at 3 months; P<0.01) and an increased left ventricular ejection fraction (44+/-13% vs. 49+/-17% at 3 months; P=0.02). The number of ventricular premature beats remained unchanged (10+/-24x10(2)/24h vs. 8+/-23x10(2)/24h at 3 months (P=NS) and 12+/-30x10(2)/24h at 6 months (P=NS)). At 3 months follow-up, bone marrow cell injection did not prolong electrogram duration (15.9+/-4.6 ms vs. 15.6+/-4.0 ms; P=NS), decrease electrogram amplitude (3.8+/-1.5 mV vs. 3.8+/-1.5 mV; P=NS), or increase fragmentation (2.0+/-0.5 vs. 1.9+/-0.4; P=NS). CONCLUSION: Intramyocardial bone marrow cell injection does not increase the incidence of ventricular arrhythmias and does not alter the electrophysiological properties of the injected myocardium. 相似文献
2.
目的 :探讨通心络治疗心绞痛的临床疗效。方法 :选择 80例心绞痛患者随机分成治疗组和对照组 ,治疗组在内科常规治疗的基础上加用通心络口服 ,观察两组患者症状缓解情况以及停药后复发情况。结果 :治疗组的心绞痛疗效、复发率分别为 95 %和 16.7% ,对照组分别为 62 .5 %和 5 2 % ,有显著差异(P <0 .0 5 )。结论 :通心络在治疗心绞痛中疗效显著 ,复发率低 ,使用方便 ,是较理想的药物。 相似文献
3.
目的 观察祛瘀消斑胶囊治疗不稳定型心绞痛及对其血浆Fib和DD水平的影响。方法 对 4 0例不稳定型心绞痛患者随机分为常规西药加祛瘀消斑胶囊治疗组 (治疗组 )和常规西药治疗组 (对照组 ) ,治疗组与对照组各 2 0例。采用相应药物治疗 4周后 ,观察 2组患者的临床疗效、心电图改善及硝酸酯类药物的停减率 ,以及血浆Fib、DD水平变化 ,并进行比较分析。结果 治疗组可显著改善心绞痛症状 ,与对照组比较有显著性差异 (P <0 .0 5 ) ,2组患者心电图改善情况及硝酸酯类药物减停率无显著性差异 (P >0 .0 5 )。治疗组降低Fib、DD水平 ,与对照组比较有显著性差异 (P <0 .0 5 )。 2组均未出现明显不良反应。结论 祛瘀消斑胶囊可显著降低不稳定型心绞痛患者Fib、DD水平 ,联合西药治疗不稳定型心绞痛 ,疗效优于单用西药 ,且安全可靠。 相似文献
4.
低分子肝素对不稳定型心绞痛病理生理干预作用的研究 总被引:1,自引:0,他引:1
目的:观察低分子肝素(LMWH)对不稳定型心绞痛((UAP)的临床症状、心电图、血脂以及内皮素(ET)的影响。方法:前瞻性地将84例UAP患者随机分为两组:对照组使用硝酸甘油、倍他乐克、阿司匹林等药物;治疗组(LMWH组)在上述治疗基础上加用LMWH(速避凝)。治疗前后调查临床症状以及心电图改变,抽血测定血脂、红细胞压积、血小板及内皮素水平的变化。结果:两组治疗后,患者心绞痛发作次数、持续时间以及硝酸甘油的用量明显减少,心电图明显改善,且LMWH组优于对照组(P<0.05)。LMWH治疗后,患者HCT、TC、TG及ET较治疗前明显降低(P<0.05)。对照组血浆ET水平无变化。结论:LMWH对UAP患者不仅具有抗凝抗栓作用,而且可以降低血液粘度、保护血管内皮细胞,纠正脂类代谢紊乱状态, 相似文献
5.
Quality of life was assessed 46 months after an acutemyocardial infarction in a randomized double-blind study ofenalapril versus placebo. Quality of life was evaluated usingthe Nottingham Health Profile (NHP), the Physical Symptoms DistressIndex (PSDI), the Work Performance Scale (WPS) and the LifeSatisfaction Index (LSI). The study comprised 36 women (aged4685 years, mean 68) and 96 males (aged 3981 years,mean 62). Quality of life did not differ significantly between patientstreated with enalapril versus placebo. The scores were (enalaprilvs placebo, mean± SE): average NHP 15.4 ± 2.3vs 17.1 ± 2.3; PSDI 9.5± 1.0 vs 10.8 ±0.9; WPS 19.8 ± 2.0 vs 19.4 ± 1.4; LSI 24.1 ±1.0 vs 22.5 ±1.4. Men reported a better quality of lifethan women on most assessments, and non-smokers and ex-smokersbetter than smokers. Patients with moderate or severe anginapectoris had a worse quality of life measured by PSDI and NHPthan patients with minimal or no angina pectoris. Patients withcongestive heart failure had a higher PSDI than those without(13.6 ± 1.7 vs 9.4 ± 0.7, P<0.05), while nosignificant differences were observed in the NHP scores. In conclusion, quality of life was similar in enalapril andplacebo- treated patients after an acute myocardial infarction.However, it was reduced in patients with angina pectoris orheart failure and in those who continued smoking. 相似文献
6.
Clinical significance of 201Tl reverse redistribution in patients with aorto-coronary bypass surgery
Tsunehiko Nishimura Tashiisa Uehara Kohei Hayashida Takahira Kozuka 《European journal of nuclear medicine and molecular imaging》1987,13(3):139-142
Detection of myocardial ischemia by the stress thallium scan has traditionally been performed using transient defect analysis on exercise, followed by redistribution studies. Worsening of the 201Tl myocardial image from exercise to redistribution is referred to as reverse redistribution. In this study, we found reverse redistribution in 10 (21%) of 48 angina pectoris patients who had undergone aortocoronary bypass surgery. The clinical significance of this phenomenon in these patients was investigated in relation to angiographic and surgical findings. Reverse redistribution was found to occur in regions which were supplied by bypass grafts. These areas showed increased coronary blood flow and rapid thallium washout. Our results indicate that a perfusion defect in the bypass region of the redistribution image might be caused by relatively rapid washout in the bypass graft region compared to the adjacent normal myocardium. These results should be considered in the clinical interpretation of stress thallium scans. 相似文献
7.
In humans, electrical, bipolar, bilateral carotid sinus nerve stimulation (CSNS; impulse duration 0.35 ms) was applied, using frequencies between 10 and 110 Hz and voltages between individual thresholds and maximal amplitudes of stimulation. Ten anginal patients and two hypertensive patients were studied at an interval of up to 12 years after implantation of electrodes and a radiofrequency receiver for chronic therapeutic CSNS. In search of combinations of frequency and voltage of CSNS, eliciting largest ("optimal") depressor responses of blood pressure and heart rate in the individual patient, Rechenberg's evolution strategy was applied. This strategy simulates mutation and selection of biological evolution. In each patient and on each test stimulation, a value of quality was computed from actual heart rate and blood pressure values as a selection criterion for the strategy. Either responses to uninterrupted CSNS were investigated, while stimulation parameters were adjusted every 3 min, according to the strategy, or responses to 3 min of CSNS after a change in stimulation parameters were compared to intercalated 3-min control periods. In each patient, one or more combined settings of frequency and voltage elicited "optimal" responses. In principle, "optimal" CSNS frequencies ranged between 35 and 105 Hz with large interindividual differences. Due to chronic implantation of electrodes and technical features of radiofrequency transmitted stimulation energy, interindividually different voltages led to an optimal response to CSNS. Also according to the present results, the frequency of CSNS has to be determined individually. It is concluded that the evolution strategy was applied successfully, because voltage and frequency settings leading to "optimal" responses were found within 90-180 min, whereas intraindividual systematic investigations would not be feasible due to their necessarily very long duration. So far, only short-term responses have been evaluated. A broader use of the strategy in other applications is encouraged, as for example in pacemaker optimization and especially in functional electrostimulation. 相似文献
8.
目的 :探讨红细胞聚集改变与纤维蛋白原的关系及其对心绞痛发病的影响。方法 :测定 80例不稳定性心绞痛患者和 40例健康人的红细胞聚集指数 (光密度法 )、红细胞变形指数 (激光衍射法 )、血浆及全血粘度 (旋转式粘度计 )和纤维蛋白原 (双缩脲法 )。结果 :不稳定性心绞痛患者红细胞聚集指数和全血粘度 ( 4 0s- 1 )及纤维蛋白原浓度均高于对照组 (P均 <0 .0 1~ 0 .0 5 ) ,且红细胞聚集指数与纤维蛋白原呈直线正相关 ,与全血粘度 ( 4 0s- 1 )无相关性。结论 :纤维蛋白原含量增加是红细胞聚集增强的主要原因之一 ;红细胞聚集能力增强导致血液高粘滞 ,与心绞痛发作有关 ;选择 10s- 1 以下切变率测定低切全血粘度 ,利于观察全血粘度与红细胞聚集的关系 相似文献
9.
Dr. rer. nat. G. Ollenschläger H. Gofferje L. Horbach H. Prestele K. Schultis 《Journal of molecular medicine (Berlin, Germany)》1981,59(9):437-449
Zusammenfassung Die Kinetik kurzlebiger Plasmaproteine im Postaggressionssyndrom wurde vergleichend bei Patienten nach Herzinfarkt (HI) mit und ohne klinische Komplikationen und nach Angina Pectoris-Anfall (AP) am Beispiel der Akut-Phase-Proteine 1-Antitrypsin, C-reaktives Protein, Fibrinogen und Haptoglobin sowie der Transportproteine Präalbumin und Transferrin nach der Methode der radialen Immundiffusion untersucht. Während AP keinen Einfluß auf die Proteinkinetik ausübt, zeigen sich nach HI ein kontinuierlicher Anstieg der Akut-Phase-Proteine und ein dazu parallel verlaufender Abfall der Transportproteine mit Maximal- bzw. Minimal-Konzentrationen zwischen dem 3. und 5. Tag nach dem Ereignis und anschließender Rückbildung zu den Ausgangswerten. Die Veränderungen, die in ähnlicher Weise auch nach chirurgischen Traumata beobachtet werden, sind abhängig vom Schweregrad der Erkrankung und entsprechend prognostisch verwertbar.Im Postaggressionssyndrom wird demnach das Verhalten der nahrungsabhängigen Proteine Präalbumin und Transferrin sowohl durch Art und Stärke des Streßeinflusses als auch durch den Ernährungszustand beeinflußt. Der Mechanismus dieser Veränderungen und die Konsequenzen für die Verwendung der Proteine als diagnostische Kenngrößen werden diskutiert. 相似文献
10.
对黄杨碱治疗的62例冠心病心绞痛甲襞微循环变化进行观察。结果表明:96.8%(60/62)的病例甲襞微循环有异常改变,且病情愈重其改变愈明显。用该药4.5mg/日(1.5mg,tid)治疗60天结果显示:绝大多数微循环异常指标都获改善(P<0.05~0.01),并认为该药有部分类似茛菪类药物的作用。对少数严重病例的异常微循环改善不明显。心绞痛缓解率及心电图(ST、T)改善率分别在70%以上及50%~70%之间。面药对降高明固醇及高甘油三酯作用不明显(P>0.05),而对升高高密度脂蛋白具有较好疗效(P<0.05)。该药无明显毒副作用。 相似文献