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71.
BackgroundHeart rate variability (HRV) and heart rate turbulence are known to be disturbed and associated with excess mortality in heart failure. The aim of this study was to investigate whether losartan, when added on top of β-blocker and angiotensin-converting enzyme inhibitor (ACEI) therapy, could improve these indices in patients with systolic heart failure.Methods and ResultsSeventy-seven patients (mean age 60.4 ± 8.0, 80.5% male) with ischemic cardiomyopathy (mean ejection fraction 34.5 ± 4.4%) and New York Heart Association Class II-III heart failure symptoms, already receiving a β-blocker and an ACEI, were randomly assigned to either open-label losartan (losartan group) or no additional drug (control group) in a 2:1 ratio and the patients were followed for 12 weeks. The HRV and heart rate turbulence indices were calculated from 24-hour Holter recordings both at the beginning and at the end of follow-up. The baseline clinical characteristics, HRV, and heart rate turbulence indices were similar in the 2 groups. At 12 weeks of follow-up, all HRV parameters except pNN50 increased (SDNN: 113.2 ± 34.2 versus 127.8 ± 24.1, P = .001; SDANN: 101.5 ± 31.7 versus 115.2 ± 22.0, P = .001; triangular index: 29.9 ± 11.1 versus 34.2 ± 7.9, P = .008; RMSSD: 29.1 ± 20.2 versus 34.3 ± 23.0, P = .009; NN50: 5015.3 ± 5554.9 versus 6446.7 ± 6101.1, P = .024; NN50: 5.65 ± 6.41 versus 7.24 ± 6.99, P = .089; SDNNi: 45.1 ± 13.3 versus 50.3 ± 14.5, P = .004), turbulence onset decreased (−0. 61 ± 1.70 versus −1.24 ± 1.31, P = .003) and turbulence slope increased (4.107 ± 3.881 versus 5.940 ± 4.281, P = .004) significantly in the losartan group as compared with controls.ConclusionsA 12-week-long losartan therapy significantly improved HRV and heart rate turbulence in patients with Class II-III heart failure and ischemic cardiomyopathy already on β-blockers and ACEI.  相似文献   
72.
OBJECTIVE: Myocardial fractional flow reserve (FFR) is utilized to determine the hemodynamic significance of coronary stenoses. We sought to determine the effect, if any, of metoprolol on FFR in patients with coronary stenoses of intermediate severity. METHODS AND RESULTS: Eighteen patients (10 males, mean age, 59.4 +/- 7.7 years) with isolated, intermediate (30% to 70% narrowing on coronary angiogram) lesions on the proximal LAD and a preserved ejection fraction, underwent FFR measurement using a 0.014 inch pressurewire and intracoronary adenosine injection before and after intravenous metoprolol at a dose that achieved at least a 10% decrease in the heart rate. Heart rate dropped significantly with metoprolol. At the premetoprolol measurement, aortic pressure (Pa) remained essentially the same (105.7 +/- 11.5 versus 105.6 +/- 11.6 mmHg, P > 0.05) and distal coronary pressure (Pd) dropped significantly by 9% from 96.3 +/- 12.7 to 87.4 +/- 13.4 mmHg (P < 0.001) after adenosine injection yielding an FFR(1) of 0.83 +/- 0.07. At the postmetoprolol phase, Pa dropped nonsignificantly by 2% from 104.4 +/- 12.8 to 102.4 +/- 14.3 mmHg (P = 0.09) and Pd dropped significantly by 11% from 95.7 +/- 14.4 to 85.3 +/- 16.4 mmHg (P < 0.001) after adenosine injection, yielding an FFR(2) of 0.83 +/- 0.08, which was almost exactly the same as FFR(1) (P > 0.05). CONCLUSION: In this study, FFR was found not to be influenced by metoprolol treatment in patients with intermediate coronary stenoses and a preserved ejection fraction.  相似文献   
73.
Our objective in this study was to compare the demographics and clinical characteristics of patients with episodic and chronic obsessive-compulsive disorder (OCD). We recruited 128 outpatients with a primary diagnosis of OCD according to DSM-IV diagnostic criteria. The episodic (n=24) and chronic (n=104) OCD patient groups were compared with respect to demographic variables and scores from various psychiatric rating scales. The severity of compulsions was found to be significantly lower in the episodic OCD group than in the chronic OCD group. When the frequency of Axis I disorders was assessed in the two groups, bipolar disorder was found to have a significantly higher prevalence rate in the episodic OCD group than that in the chronic OCD group. The results of our study point to the possibility of an association between a subgroup of OCD with an episodic course and bipolar disorder. The evidence of such a relationship, which needs to be confirmed in a larger sample, might expand the scope of the clinical assessment and therapy of this subgroup of OCD.  相似文献   
74.
An unusual case of total occlusion of aorta just distal to the left subclavian artery, bicuspid aortic valve, and occluded left external iliac artery in a 21-year-old man who was admitted with headache and severe hypertension is presented. We wish to report this case because so far there have been none reported with such multiple aortic abnormalities, although several documented cases of isolated total occlusion of aorta exist. Our patient underwent a successful surgical correction, i.e., patch plasty to the coarcted segment and end to side – end to side aortal-aortal bypass with Dacron graft.  相似文献   
75.
BACKGROUND: Endothelial dysfunction and subsequently impaired microvascular circulation are the leading mechanisms in the development of cardiac syndrome X (CSX). The study evaluated the plasma asymmetric dimethylarginine (ADMA) and L-arginine levels of the patients with CSX and the control group and aimed to determine any relationship between these parameters and epicardial coronary blood flow and myocardial tissue perfusion. METHODS: The study group consisted of 32 patients (mean age: 52.6+/-9.4 years, 14 men) with typical exertional angina, positive exercise test, and normal coronary arteries diagnosed as CSX. Plasma ADMA, L-arginine levels, and L-arginine/ADMA ratio were compared with the values of the control group, which consisted of 17 age-matched and sex-matched individuals. Concentrations of L-arginine and ADMA were measured by high-performance liquid chromatography. In all the coronary territories, epicardial coronary flow was assessed by thrombolysis in myocardial infarction (TIMI) frame count (TFC) method, and tissue level perfusion, by myocardial blush grade (MBG) method. A MBG score less than 3 was considered an impaired myocardial perfusion, and a MBG score of '3' in all the coronary territories, a normal myocardial perfusion. RESULTS: The plasma ADMA levels of the study group were higher than those of the control group (0.83+/-0.38 vs. 0.55+/-0.44 micromol/l, P=0.03), whereas plasma L-arginine levels were similar in both groups (70.25+/-21.89 vs. 76.09+/-18.22 micromol/l, P=0.36), resulting in a diminished L-arginine/ADMA ratio in the patients with CSX [82.3 (60.2-128.8) vs. 242.2 (76.7-386.4), P=0.003]. In CSX group, the patients with abnormal myocardial tissue perfusion had increased plasma ADMA levels compared with those with normal tissue perfusion (0.99+/-0.37 vs. 0.69+/-0.34 micromol/l, P=0.02), whereas plasma L-arginine levels were similar in both groups. No correlations were observed between TFC values and plasma ADMA, L-arginine levels, and L-arginine/ADMA ratio. Plasma ADMA levels, however, were negatively correlated with MBG scores (r=-0.349, P=0.014). CONCLUSION: We have shown for the first time that in the patients with CSX, increased plasma ADMA levels might be associated with impaired myocardial tissue perfusion when assessed by MBG.  相似文献   
76.
AIMS: To demonstrate whether there is a relationship between the presence of nonalcoholic fatty liver disease (NAFLD) and the presence and extent of coronary artery disease (CAD). PATIENTS AND METHODS: Ninety-two consecutive patients who planned to undergo coronary angiographies (CAG) without known CAD, other than findings of acute coronary syndrome, were enrolled in this study. Abdominal ultrasonography was performed before the CAG to detect NAFLD. CAD was defined as a stenosis of at least 50% in at least one major coronary artery. The extent of CAD was measured according to the number of major coronary artery/arteries affected by CAD. All the risk factors for CAD were included in a binary logistic regression model. Forward, backward, or step-wise selections were not used. P<0.05 was accepted as being significant. RESULTS: Sixty-five of the 92 patients (70.7%) were detected, by abdominal ultrasonography, to have fatty liver and 43 patients out of 92 (46.7%) were detected, by CAG, to have significant CAD. According to the results of logistic regression analysis, the presence of NAFLD independently increased the risk for CAD, as seen in CAG [odds ratio (OR), 95% confidence interval (CI): 6.73 (1.14-39.61); P=0.035]; this was despite factoring in the other risk factors for CAD and the components of metabolic syndrome. NAFLD was more commonly found in patients as the extent of CAD increased (P=0.001). CONCLUSION: The presence of NAFLD is independently associated with the presence and extent of CAD. Future studies are needed to explain the mechanisms of this relationship.  相似文献   
77.
Use of individually ventilated caging (IVC) systems for mouse-based laboratory investigation has dramatically increased. We found that without mice present, intra-cage oxygen concentration was comparable (21%) between IVC housing and ambient environment caging (AEC) that used wire top lids. However, when mice were housed 4-to-a-cage for 1week, intra-cage oxygen dropped to 20.5% in IVC housing as compared to 21% for AEC housing. IVC intra-cage humidity was also elevated relative to AEC housing. Mice raised in IVC housing as compared to mice raised in AEC housing had higher RBC mass, hematocrit and hemoglobin concentrations. They also had elevated platelet counts but lower white blood cell counts. IVC mice, relative to AEC mice, had increased saccharin preference and increased fluid consumption but similar locomotion, food intake, social exploration and novel object recognition when tested in an AEC environment. Taken together, these data indicate that ventilated caging systems can have a 0.5% reduction from ambient oxygen concentration that is coupled to mouse red blood cell indices indicative of chronic exposure to a hypoxia. Importantly, IVC housing can impact behavioral testing for depressive-like behavior.  相似文献   
78.
79.
In an attempt to determine the early and late outcomes of small vessel stenting, we retrospectively evaluated our database on 51 consecutive patients (41 males, mean age, 57.1 +/- 10.1 years) who underwent stenting of at least one significant lesion in a coronary artery with a reference vessel diameter (RVD) <2.8 mm between March 1999 and March 2001. Sixty balloon expandable tubular stents were implanted in 57 lesions (29 Type B2/C, mean RVD: 2.54 +/- 0.16 mm) without intravascular ultrasound guidance under a heparin-aspirin-ticlopidine regimen. The mean diameter stenosis (DS) decreased from 75.8 +/- 13.6% to 4.2 +/- 1.9% (P<0.0001) with stenting at a mean deployment pressure of 13.6 +/- 1.7 atm and a final balloon to RVD ratio (FB/RVD) of 1.08 +/- 0.03. All stents were deployed successfully. Acute stent thrombosis occurred in 3 patients (6%), one died, and 2 developed non-Q-wave myocardial infarction (procedural success 94%). Clinical follow-up, available in 48 patients, revealed a 29% target lesion revascularization rate, a 2% myocardial infarction rate, and a 71% event-free survival at a mean of 11.6 months. Angiographic follow-up, available in 40 patients, showed a DS of 48.8 +/- 31.3% and a binary restenosis rate of 50% at a mean of 7.7 months. The FB/RVD ratio was significantly lower in the group with restenosis than in the group without (1.06 +/- 0.02 vs 1.1 +/- 0.05, P = 0.04). Subgroup analysis yielded a significantly greater rate of restenosis in diabetics with complex (Type B2/C) lesion morphology compared to nondiabetics with simple (Type A/B1) lesions (75% vs 21%, P < 0.05). In conclusion, stenting in vessels <2.8 mm was found to be associated with a high rate of acute stent thrombosis and in-stent restenosis. Further analysis detected a subgroup of patients without diabetes or complex lesions who could be stented with an acceptable in-stent restenosis rate.  相似文献   
80.
Accessory mitral valve tissue is a rare finding in echocardiographic examinations. We report a case with an echocardiographically detected accessory mitral valve tissue which caused left ventricular outflow tract obstruction and was presumably responsible for a cerebrovascular accident.  相似文献   
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