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991.
Information about the effects of angiotensin II receptor blocker (ARB) therapy on the hemodynamic and cardiac structure in patients with chronic aortic regurgitation (CAR) and isolated systolic hypertension (ISH) is limited. This study planned to test the hypothesis that l -arginine could further enhance the beneficial effect of an ARB, losartan, and provide a favorable effect on the natural history of CAR and ISH. Sixty patients with CAR and ISH were enrolled in a randomized, double-blind trial comparing hemodynamic and ultrasonic change in two treatment arms: losartan +  l -arginine and losartan-only treated groups. Serial echocardiographic and hemodynamic studies were evaluated before and after treatment. Both groups had a significant reduction in systolic blood pressure (SBP) and diastolic blood pressure (DBP), left ventricular end-diastolic volume index (LVEDVI), LV end-systolic volume index (LVESVI), LV mass index (LVMI), and LV mean wall stress after 6- and 12-month treatment ( p <0.01 in all comparisons). Both groups had a significant increase in LV ejection fraction and exercise duration after 6- and 12-month treatment ( p  < 0.01 in all comparisons). Using multivariate linear regression analysis, only losartan +  l -arginine therapy achieved a significantly lower LVESVI (38.89 ± 0.23 mL/m 2 ), LVEDVI (102.3 ± 0.3 mL/m 2 ), LVMI (107.6 ± 0.3 g/m 2 ), SBP (123.5 ± 1.0 mm Hg), and greater exercise duration (7.38 ± 0.02 minutes) than those of the losartan-only treated groups ( p <0.01 in all comparisons). These findings suggest that early co-administrative strategy provides a beneficial approach to favorably influence the natural history of CAR.  相似文献   
992.
目的探讨先心病伴严重肺动脉高压矫治术患者围术期监测及治疗肺动脉高压的麻醉处理。方法选32例肺动脉平均压〉70mmHg的患者,采用主肺动脉置管法持续测压,并通过主肺动脉导管持续泵入前列腺素E1(5μg·kg^-1·min^-1),观察转流后和术后第3天的肺动脉压。结果肺动脉压出院时[(43.90±12.42)mmHg]与术前[(85.88±13.26)mmHg]比较,P〈0.01;术后第3天[(29.40±13.41)mmHg]与术中[(36.10±16.20)mmHg]比较,P〈0.05。结论以动力性为主的严重肺动脉高压患者,虽经外科治疗降低了肺动脉压力,但仍需在麻醉处理上采取必要和有效的措施去预防和治疗肺血管阻力的不断升高。  相似文献   
993.
原发性高血压患者血压变异性的临床研究   总被引:1,自引:0,他引:1  
目的 探讨原发性高血压 (EH )患者血压变异性与靶器官损害、血压增高的程度及年龄的关系。方法 对65例EH患者及 40例正常人 (对照组 )进行 2 4h动态血压监测 ,以测定的血压标准差作为血压变异性指标。结果 EH组血压变异性明显大于对照组 ,Ⅱ、Ⅲ期EH患者血压变异性明显大于Ⅰ期EH患者 ;EH患者血压变异性随血压水平的增加而逐渐增大 ,年龄≤ 5 5岁者 ,其血压变异性随年龄的增加而增大 ,年龄 >5 5岁者 ,其血压变异性不再随继续增加。结论 EH患者血压变异性明显增加 ,且靶器官损害越重 ,血压值越高 ,在一定范围内年龄越大则血压变异性越大  相似文献   
994.
To clarify whether fosinopril monotherapy can improve left ventricular diastolic function (LVDF) in young mildly hypertensives without hypertrophy, we studied 66 patients (pts) with diastolic blood pressure 90–100 mmHg, aged <45 years, with normal 2-dimensional echocardiography (2-D echo), and impaired DF. Impaired DF was defined as a Doppler transmitral early (E) to atrial (A) filling velocity ratio (E/A ratio) <1. Thirty-eight pts were selected for fosinopril monotherapy. Mean age was 36 years. Duration of documented hypertension was 5.4 years. Mean daily dose of fosinopril was 20 mg. Twenty-eight controls were treated with hydrochlorothiazide and hydralazine combination. Sixty-six age- and sex-matched healthy subjects served to establish normal reference values of 2-D and Doppler echo measurements. All hypertensives were treated for 30 months and re-examined 4 weeks after cessation of treatment. The fosinopril-treated group showed improvements in transmitral E (52 ± 8 cm/s, vs. 61 ± 9 cm/s, p < 0.01), A (56 ± 9 cm/s, vs. 47 ± 6 cm/s, p < 0.05), and E/A ratio (0.93 ± 0.16, vs. 1.29 ± 0.18, p < 0.01). Moreover, the early to atrial velocity-time integral ratio (1.31 ± 0.10, vs. 2.24 ± 0.10, p < 0.001) improved. The pulmonary venous flow pattern normalized after fosinopril therapy. LV mass index, relative wall thickness, LV dimension, left atrial dimension, fractional shortening, heart rate, and body mass index did not change. The hydrochlorothiazide-hydralazine combination-treated group did not show an improved diastolic function. It is concluded that long-term fosinopril monotherapy leads to an improvement of impaired LVDF in young mildly hypertensives without hypertrophy.  相似文献   
995.
Our objective was to study meconium-induced lung injury in isolated perfused rat lungs exposed to anoxia. Our working hypothesis was that meconium-induced lung injury is independent of preexisting hypoxia, and that hypoxia will increase severity of lung injury observed after meconium aspiration. We compared five different groups of animals (n = 5) for pulmonary arterial pressure (PAP), weight lung changes, and TNFalpha expression. Group I had lungs instilled with 4 ml of normal saline. Group II had lungs exposed to 5 min of anoxia. Group III had lungs instilled with 4 ml of 30% filtered human meconium. Group IV had lungs exposed to 5 min of anoxia and then instilled with 4 ml of 30% filtered human meconium. Group V had lungs instilled with 4 ml of 30% unfiltered human meconium. Our subjects were adult Sprague-Dawley rats. The isolated rat lung model was prepared according to Levey and Gast (J Appl Physiol 1966;21:313-316). Lungs were ventilated with room air. Anoxia was caused by the use of N(2). The pulmonary artery was cannulated, and pulmonary arterial pressure and lung weight were measured. Lung weight and pulmonary arterial pressure were monitored for 120 min, and TNFalpha levels were measured in effluent at 15, 30, 60, and 120 min. Experiments were done at the Michael Reese Hospital (Chicago, IL). At the end of the experiment, PAP reached its highest values in group V (10.0 +/- 1.7 mmHg). Final PAPs in groups I-IV were: 4.85 +/- 0.3, 4.99 +/- 0.4, 5.93 +/- 0.3, and 7.25 +/- 0.51 mmHg, respectively). Lung wet weight increased significantly only in groups IV and V vs. group I; at 120 min, they were: 0.96 +/- 0.3 g, P < 0.01, and 1.5 g +/- 0.2 g, P < 0.01, respectively. TNFalpha levels did not change significantly over time in group I. TNFalpha is a marker as well as proprietor of pulmonary inflammatory response. TNFalpha reached its highest levels in groups IV and V: 595 and 753 pg/ml at 120 min, respectively. In conclusion, a short episode of anoxia prior to meconium aspiration may increase lung sensitivity to meconium-induced lung injury. This effect may be moderated by the TNFalpha present in the pulmonary circulation.  相似文献   
996.
Abstract Hyperdynamic circulation and portal hypertension characterize acute on chronic liver failure (AoCLF), partially because of circulating mediators. Molecular Absorbents Recirculating System (MARS) may remove some of these substances. The objective of this study was to evaluate the effect of MARS on portal pressure, systemic haemodynamic and endogenous vasoactive systems. MARS treatment was performed in four patients with AoCLF (mean age 36.2 ± 3.1 years; Child–Pugh C 11 ± 1.8 points; three AAH and one NASH). Systemic and splanchnic haemodynamic measurements were performed before and after each session. Plasmatic renin activity (PRA) and NE were measured at baseline, at the end of the sessions and 10 days after MARS. All patients had severe portal hypertension (HVPG = 23 ± 7 mmHg) and pronounced hyperdynamic circulation (MAP 77.8 ± 11.7 mmHg; CO 11.2 ± 1.6 L/min; SVRI 478.5 ± 105 dyne s/cm5). HVPG decreased at the end of the first session in all patients (23 ± 7 mmHg vs 17.3 ± 9.9 mmHg; P = 0.05; mean decrease 32 ± 24%) because of a decrease in WHVP (40.7 ± 5.6 mmHg vs 34 ± 9.6 mmHg; P = 0.025; mean decrease 18 ± 19%). MARS significantly attenuated hyperdynamic circulation as shown by a decrease in CO (11.2 ± 1.6 L/min vs 9.4 ± 2.1 L/min; mean decrease 12.3%), with an increase in MAP (77.8 ± 11.7 mmHg vs 84.2 ± 8 mmHg; mean increase 9.2%) and in SVRI (478.5 ± 105 dyne s/cm5 vs 622 ± 198 dyne s/cm5; mean increase 41%). PRA and NE decreased significantly (14.2 ± 17.2 ng/mL/h vs 3.7 ± 3.4 ng/mL/h; 1319 ± 1002 pg/mL vs 617 ± 260 pg/mL, respectively). The NE decrease was correlated to HVPG decrease (r = 1, P = 0.01). MARS decreases portal hypertension and ameliorates hyperdynamic circulation in patients with AoCLF, probably mediated by clearance of vasoactive substances. Further studies are necessary to confirm these results.  相似文献   
997.
This case report describes the feasibility and potential benefit of the use of a high-speed rotational atherectomy device (the Rotablator?) in the treatment of renovascular hypertension in a patient with a recorded restenosis of an ostial renal artery lesion following standard balloon angioplasty.  相似文献   
998.
目的 观察手术对老年高血压病患者血小板活化功能的影响。方法 选择 110例老年择期手术患者 ,按有无高血压病分成高血压病组和对照组 ,分别于手术前和手术后 30min抽肘静脉血送实验室 ,用流式细胞分析仪测定CD6 2P、CD6 3、CD4 1含量。结果 术前高血压病组患者的CD6 2P、CD6 3、CD4 1较对照组明显增高 ,差异有显著性意义(P <0 .0 5 ) ;术后 2组患者的CD6 2P、CD6 3、CD4 1较术前均明显增高 ,其中高血压病组更高 ,差异有显著性意义 (P<0 .0 1)。结论 手术更易激活老年高血压病患者的血小板功能 ,增加血栓性并发症的发生率 ,应注意围手术期的抗凝措施。  相似文献   
999.
Sublethal injury of the liver with carbon tetrachloride (CCI4) induces the modulation of hepatic stellate cells to their myofibroblast (MFB) phenotype. Pretreatment or concomitant treatment with interferon gamma (IFNγ) has been shown to inhibit this phenomenon. The aim of this study was to investigate the influence of IFNγ treatment (50 000 IU s.c. each day for 5 days) in rats with an established cirrhosis. Cirrhosis was induced with nine doses of CCI4. Comparison of biopsies before and after treatment with IFNγ showed that the number of MFB present, identified by their α-smooth muscle actin immunoreactivity, was markedly reduced. Pressure-flow curves were constructed in isolated perfused liver preparations from IFNγ-treated and saline-treated cirrhotic rats and analysed to obtain the extrapolated zero-flow intercept (P0, an index of hepatic vascular distensibility) and the vasodilator-induced change in resistance at a flow rate of 1 mL/min per g (ΔR1 an indication of the level of intrinsic vascular tone). In IFNγ-treated rats, portal venous pressure measured in vivo was significantly reduced compared with controls (11.9±1.2 vs 16.0 ± 0.5 mmHg, P < 0.05), P0 was lower (2.03 ± 0.18 vs 2.87 ± 0.32 mmHg, P < 0.05) and ΔR1 was decreased (0.39 ± 0.15 vs 1.02 ± 0.19 mmHg/mL per min per g, P < 0.05). The findings indicate that treatment with IFNγ is effective in reducing MFB density in established CCI4-cirrhosis in the rat and results in a marked improvement in intrahepatic haemodynamics.  相似文献   
1000.
非杓型高血压对左心室肥厚的影响及其临床意义   总被引:11,自引:0,他引:11  
目的:以杓型高血压患者为对照,探讨非杓型高血压在左心室肥厚发生和发展中的作用。方法:应用24小时动态血压和超声心动图检测230例高血压患者,选择年龄、病程、昼间血压基本相同的杓型、非杓型高血压患者150例,其中男性各45例,女性各30例。结果:非杓型高血压患者舒张末期左心房内径显著大于杓型高血压患者,男性分别为35.8±2.9mm与31.2±2.7mm(P<0.01);女性分别为32.4±2.5mm与29.4±1.8mm(P<0.05)。女性杓型、非杓型高血压患者间舒张末期左心室内径的差异(49.5±3.2mm与54.8±3.7mm,P<0.01)比男性(53.8±4.6mm与57.4±4.5mm,P<0.05)更为显著。非杓型高血压患者左心室重量指数显著大于杓型高血压患者,男性分别为158.0±7.9g/m2与130.0±6.7g/m2(P<0.01);女性分别为138.0±5.6g/m2与115.0±4.7g/m2(P<0.01)。结论:非杓型高血压患者左心室肥厚的检出率比杓型高血压患者为高。  相似文献   
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