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991.
Temporal stability of lipid responses to acute psychological stress in middle-aged men 总被引:3,自引:0,他引:3
The purpose of this study was to establish the temporal stability of lipid responses to acute psychological stress. Eighteen men were tested twice an average of 16.2 months apart in identical laboratory reactivity protocols. Total cholesterol, triglycerides, high- and low-density lipoprotein-cholesterol, plasma volume, heart rate, and blood pressure were assessed during rest, serial subtraction, and speech. After correction for changes in plasma volume, significant elevations were recorded for all variables during the speech task, but fewer variables showed changes during the serial subtraction task. Strong intersession associations were found when considering levels of the variables during baseline and stress (rs≥58). Correlations for the change scores ranged from .36 to .52 for the atherogenic lipids and from .39 to .87 for the cardiovascular variables. Little evidence was found for stability of plasma volume changes. There is moderate to high temporal stability of the atherogenic lipids when considering rest and stress levels and small to moderate temporal stability when considering change scores. 相似文献
992.
G. Christ M. Zehetgruber G. Mundigler F. Coraim G. Laufer E. Wolner G. Maurer P. Siostrzonek 《Intensive care medicine》1997,23(3):297-300
Objective: To demonstrate that emergency aortic valve replacement can be successfully performed in patients with critical aortic stenosis and reduced left ventricular function even in cardiogenic shock with associated severe multiple organ failure. Design: Retrospective, consecutive case series. Setting: Multidisciplinary intensive care unit of a tertiary care university hospital. Patients: Five patients admitted to the intensive care unit with critical aortic stenosis (aortic valve area 0.56 ± 0.13 cm2) and greatly reduced left ventricular ejection fraction (20 ± 3 %) in prolonged cardiogenic shock and associated multiple organ failure (Multiple organ failure score 6.8 ± 0.5; Acute Physiology, Age, and Chronic Health Evaluation III score 91 ± 27). Intervention: Emergency aortic valve replacement. Results: All patients survived with full recovery of organ function. At follow-up (18 ± 10 months) all patients were in New York Heart Association functional class I or II with improvement of left ventricular ejection fraction to 48 ± 25 %. Conclusions: This excellent outcome suggests that emergency aortic valve replacement should be strongly considered in patients with critical aortic stenosis even in cardiogenic shock and multiple organ failure. 相似文献
993.
Radiofrequency Ablation of Concealed Left Free-Wall Accessory Pathways Without Coronary Sinus Catheterization: 总被引:1,自引:0,他引:1
JOSEP BRUGADA M.D. IGNACIO GARCIA-BOLAO M.D. MARCIO FIGUEIREDO M.D. MARTÍ PUIGFEL M.D. MARIONA MATAS R.N. FRANCISCO NAVARRO-LÓPEZ M.D. 《Journal of cardiovascular electrophysiology》1997,8(3):249-253
Ablation of Concealed Accessory Pathways. Introduction: Feasibility of radiofrequency (RF) ablation using a two-catheter technique without coronary sinus catheterization was studied in 100 consecutive patients with a single concealed left free-wall accessory path-way.
Methods and Results: Tachycardia was induced by electrical stimulation in the right atrium/right ventricle, and the presence of a concealed left free-wall accessory pathway was suggested electrocardiographically (negative P wave in leads I and/or a VL during orthodromic tachycardia) or by earlier atrial activation in the pulmonary artery compared to the high right atrium. Mapping of the mitral annulus was performed during right ventricular pacing or orthodromic tachycardia, and RF energy was applied at the site with the earliest retrograde atrial activation. Ablation was considered effective if tachycardia could not be induced, and if VA dissociation or exclusive retrograde nodal conduction was observed. Ablation was initially successful in 98 of 100 patients. Mean number of radiofrequency pulses were 3.2 ± 2. Mean fluoroscopy time and total procedure time was 14 ± 9 and 107 ± 32 minutes, respectively. There were no complications related to the procedure. At a mean follow-up of 22 ± 13 months, two patients experienced tachycardia recurrence and required a second procedure, which was successful.
Conclusions: Our results suggest that RF catheter ablation of concealed left free-wall accessory pathways can be safely, effectively, and rapidly performed using a simplified two-catheter technique with no need for coronary sinus catheterization. 相似文献
Methods and Results: Tachycardia was induced by electrical stimulation in the right atrium/right ventricle, and the presence of a concealed left free-wall accessory pathway was suggested electrocardiographically (negative P wave in leads I and/or a VL during orthodromic tachycardia) or by earlier atrial activation in the pulmonary artery compared to the high right atrium. Mapping of the mitral annulus was performed during right ventricular pacing or orthodromic tachycardia, and RF energy was applied at the site with the earliest retrograde atrial activation. Ablation was considered effective if tachycardia could not be induced, and if VA dissociation or exclusive retrograde nodal conduction was observed. Ablation was initially successful in 98 of 100 patients. Mean number of radiofrequency pulses were 3.2 ± 2. Mean fluoroscopy time and total procedure time was 14 ± 9 and 107 ± 32 minutes, respectively. There were no complications related to the procedure. At a mean follow-up of 22 ± 13 months, two patients experienced tachycardia recurrence and required a second procedure, which was successful.
Conclusions: Our results suggest that RF catheter ablation of concealed left free-wall accessory pathways can be safely, effectively, and rapidly performed using a simplified two-catheter technique with no need for coronary sinus catheterization. 相似文献
994.
R G Weintraub W J Brawn A W Venables R B Mee 《The Journal of thoracic and cardiovascular surgery》1990,99(2):320-326
Before January 1987, 62 infants underwent two-patch repair of complete (51) or intermediate (11) atrioventricular septal defect at the Royal Children's Hospital, Melbourne. Median age at repair was 4.3 months and median weight was 4.4 kg. Early deaths (3%) were confined to two infants with preoperative respiratory tract infections; a further two patients died during follow-up (late mortality rate 3%). Reoperation for severe postoperative mitral regurgitation was necessary in 10 infants (16%), two of whom subsequently required mitral valve replacement with a prosthesis. Preoperative atrioventricular valve regurgitation was assessed retrospectively in 49 patients from angiography or Doppler echocardiography and was found to be absent or mild in 33 (68%), moderate in 9 (18%), and severe in 7 (14%). At the time of latest review (at a mean of 2.4 years after repair), judged from a combination of clinical and echocardiographic criteria, mitral regurgitation was absent or mild in 49 (84%) of the 58 survivors; none of them had symptomatic regurgitation or were requiring continuing medical treatment. Analysis of sequential atrioventricular valve function in 46 of the 49 patients in whom objective preoperative data were available showed no relationship between the degree of preoperative and postoperative atrioventricular valve regurgitation. Infants without Down's syndrome, however, had a significantly higher reoperation rate for severe postoperative mitral valve regurgitation (50%) than those with Down's syndrome (10%) (p = 0.007). Complete atrioventricular septal defect can be repaired in early infancy with a low mortality rate and good intermediate term results. 相似文献
995.
Mohamad H Yamani Randall C Starling James B Young Daniel Cook Yang Yu D Geoffrey Vince Patrick McCarthy Norman B Ratliff 《The Journal of heart and lung transplantation》2002,21(9):983-989
BACKGROUND: A cascade of inflammatory reactions characterize acute vascular rejection after heart transplantation. This study was undertaken to test the hypothesis that acute vascular rejection is associated with up-regulation of vitronectin receptor (alphavbeta3), increased expression of tissue factor, and activation of the extracellular matrix metalloproteinase induction system. METHODS: Acute vascular rejection developed in 14 heart transplant recipients within 2 weeks of transplantation, confirmed by immunofluorescence (AVR group). We compared these patients with 10 transplant recipients who had no evidence of acute vascular rejection or peritransplant ischemic injury (control group). We evaluated endomyocardial biopsy specimens for alphavbeta3, tissue factor, and extracellular matrix metalloproteinase inducer (EMMPRIN). RESULTS: Compared with the control group, the AVR group demonstrated evidence of significantly increased expression of alphavbeta3 (1.9-fold, p < 0.001), tissue factor (1.8-fold, p < 0.001), and EMMPRIN (1.5-fold, p < 0.001). All patients in the AVR group received plasmapheresis; 11 of 14 patients had evidence of ischemic necrosis on biopsy specimens, and 3 of 14 patients experienced hemodynamic compromise and graft dysfunction and died within 3 weeks of transplant. Another patient died at 10 months after transplant. CONCLUSIONS: Acute vascular rejection is associated with up-regulation of alphavbeta3, tissue factor, and activation of the matrix metalloproteinase induction system, which may contribute to the lethal morbidity associated with this disease. 相似文献
996.
高脂血症患者C—反应蛋白含量的变化及氟伐他汀对它的影响 总被引:4,自引:1,他引:3
Dong-Sheng Chi Feng-Xia Jin Shu-Guang Yang Yu-Wen Su Bin Ge Jie Zhang Yan Zhang Yi-Li Liu 《第一军医大学学报》2002,22(12):1109-1111
OBJECTIVE: To observe the changes of C-reactive protein (CRP) level and its relationship with blood lipids, and the effects of fluvastatin on CRP and the lipids in patients with hyperlipidemia. METHODS: Serum levels of cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very-low-density lipoprotein cholesterol (VLDL-C) and lipoprotein(a)[Lp(a)] were measured by enzyme assay, and plasma CRP level by immunonephelometry before and after fluvastatin treatment (20 mg/d for 4 weeks) in patients with hyperlipidemia. RESULTS: CRP levels were above normal in 90.3% hyperlipidemia cases in spite of the various accompanying diseases. Fluvastatin treatment significantly reduced TC (-7.49%), TG (-14.32%), LDL (-13.88%), VLDL (-18.48%) and TC/HDL(-13.50%) levels (P<0.01), and also brought down Lp(a) concentration (-13.81%). CRP levels was very effectively reduced after the treatment (-15.92%, P<0.001). No association between basal CRP levels and basal lipids and Lp(a) concentrations was observed. Positive correlation of CRP, however, was observed after fluvastatin treatment with TC/HDL (r=0.62, P=0.041) and Lp(a) (r=0.320, P=0.011), while inverse relations were noted between CRP and HDL (r=-0.288, P=0.023). CONCLUSION: CRP levels increases markedly in patients with hyperlipidemia, a fact that is independent of the accompanying diseases. In addition to modulating blood lipid levels, fluvastatin also reduces CRP level, the latter possibly serving as an independent predictive factor for atherosclerotic cardiovascular diseases and also as an indicator for estimating the effectiveness of the treatment. 相似文献
997.
缬沙坦与吲达帕胺联合用药对原发性高血压患者动态血压及胰岛素敏感性的影响 总被引:1,自引:1,他引:0
司定然 《郑州大学学报(医学版)》2002,37(4):472-474
目的:探讨缬沙坦与吲达帕胺联合应用对原发性高血压(EH)患者动态血压及胰岛素敏感性的影响。方法:对65例EH患者于治疗前和治疗24周后分别进行动态血压监测(ABPM)和胰岛素敏感性测定。结果:治疗后24h平均pSB、pDB,血压负荷较治疗前均显著降低(P<0.01)。治疗后血压昼夜节律消失者8例,较治疗前42例显著减少(P<0.01)。治疗后各时点胰岛素与血糖比值(I/G)均明显下降(P<0.01),治疗后胰岛素敏感指数(ISD)显著增高(P<0.01);治疗后葡萄糖 耐量试验120min和180min两个时点C/I比值比治疗前显著增高(P<0.01-0.05)。结论:缬沙坦与吲达帕胺联合应用可显著降低EH患者动态血压水平和血压负荷,改善血压昼夜节律,显著改善胰岛素敏感性。 相似文献
998.
J Lam R A Neirotti A Nijveld J L Schuller C M Blom-Muilwijk C A Visser 《Journal of the American Society of Echocardiography》1991,4(1):43-50
Transesophageal echocardiography was attempted in 59 pediatric patients with congenital heart disease in the operating room (n = 33) or during heart catheterization or in the intensive care unit (n = 26). Six different commercially available transducers were used with diameters ranging from 7 to 15 mm. Age ranged from 1 day to 16 years, and body weight ranged from 3.7 to 65 kg. Objectives of the study were to determine (1) minimum body weight in which transesophageal echocardiography with various probes is possible, (2) additional diagnostic value, and (3) potential applications. In three cases (one surgical and two nonsurgical) the probe could not be inserted. Minimum body weight was 17 to 20 kg for probes with a diameter of greater than or equal to 13 mm and approximately 12 kg for the 11 mm probes. A 7 mm probe, on the other hand, could be inserted easily in all patients (including a neonate) in whom transesophageal echocardiography was attempted. In 11 of 56 patients, additional diagnostic information was obtained. Thus, transesophageal echocardiography is feasible in the pediatric age group provided that special probes are used in small children. Additional diagnostic information can be obtained, and the technique is of value during cardiac surgery or balloon interventions for evaluation of the efficacy of the procedure and for monitoring ventricular function. 相似文献
999.
N-acetylcysteine modifies the acute effects of isosorbide-5-mononitrate in angina pectoris patients evaluated by exercise testing 总被引:1,自引:0,他引:1
J H Svendsen K Klarlund J Aldershvile S Waldorff 《Journal of cardiovascular pharmacology》1989,13(2):320-323
Nitrates are well established in the treatment of angina pectoris and the presence of sulfhydryl groups seems to be fundamental to nitrate-induced vasodilatation. The present study was performed to elucidate if large oral doses of N-acetylcysteine (NAC, 2,400 mg X 2), a donor of sulfhydryl groups, given together with a single oral dose of the long-acting nitrate, isosorbide-5-mononitrate (5-ISMN, 60 mg), would modify the nitrate effect evaluated by exercise testing before and after additional sublingual doses of nitroglycerin (NTG). Ten patients with angina pectoris and angiographically proven significant coronary artery disease were included. All patients received a baseline therapy with beta blockers. None of the patients had developed nitrate tolerance at inclusion. NAC/5-ISMN treatment significantly prolonged the total exercise time as compared with placebo/5-ISMN (7.7 +/- 2.1 min vs. 6.8 +/- 1.7 min, p less than 0.05). This increase was of such magnitude that no further effect was obtained after additional NTG doses. This study demonstrated that increased availability of sulfhydryl groups can increase the exercise capacity in angina pectoris patients treated with 5-ISMN without nitrate tolerance. 相似文献
1000.