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991.
The purpose of our study was to evaluate prospectively the frequency and significance of brain lesions after elective carotid endarterectomy (CAE) and carotid artery stenting (CAS) by using diffusion-weighted magnetic resonance imaging (DW MRI) and then to correlate imaging findings with neuroclinical outcomes.From February 2003 through March 2005, 95 consecutive patients underwent surgical endarterectomy or CAS (with a cerebral protection device) at our institution. A total of 59 CAE procedures were performed in 46 consecutive patients (mean age, 65.8 ± 9 yr), and 56 CAS procedures were performed in 49 consecutive patients (mean age, 66.3 ± 9 yr). Diffusion-weighted magnetic resonance imaging of the brain was performed in all patients within 24 hours of the procedure, both before and after.The post-procedural stroke rate was slightly higher in the CAS group, but this difference was not significant (5.4% vs 0). One early and 1 late death occurred in the stent group. Although the incidence of ischemic lesions was similar in both groups (surgery group, 12.5%; stent group, 13.5%), new DW MRI lesions were higher in the endarterectomy group (27.1% vs 12.5%, P=0.041). This difference was due chiefly to nonischemic lesions such as hemorrhage and watershed ischemia. In the analysis of patients with embolic ischemia, incidences of symptomatic stroke (P=0.046) and large infarct (P=0.013) were higher in the stent group.When we used protective devices during CAS, the incidence of embolic complications was similar to that of surgical enarterectomy. On the other hand, the clinical results of CAS need improvement.Key words: Arterial occlusive diseases, brain ischemia, carotid stenosis, cerebral infarction, cerebrovascular disorders, endarterectomy, carotid, intracranial embolism and thrombosis, ischemic attack, transient, prospective studies, stents, stroke/prevention & controlThe purpose of treating a stenosis of the carotid artery is to prevent stroke and to otherwise reduce the risk of cerebral ischemia. At present, carotid artery endarterectomy (CAE) and carotid artery stenting (CAS) are accepted as major therapeutic methods. The efficacy and safety of CAE in symptomatic and asymptomatic patients have been carefully evaluated in large randomized clinical trials.1–4 Nevertheless, CAS has become an attractive treatment for patients because of shorter hospital stays and the avoidance of general anaesthesia, surgical incision, and risk of cranial nerve injury.5,6 However, large-scale randomized clinical trials are needed to determine whether CAS should be the procedure of choice.Both CAE and CAS carry risk. These procedures, which are known to be associated with temporary or permanent neurologic defects, must be performed with low rates of morbidity and mortality in order to maintain short- and long-term benefits superior to those of medical treatment. Therefore, procedure-related embolic complications have become a critical issue for both CAE and CAS.Several separate studies7–12 by means of diffusion-weighted magnetic resonance imaging (DW MRI) have documented the frequency of new lesions, which presumably are infarctions due to distal embolization from friable plaque after CAE and CAS. Although most of these lesions have been clinically silent, impairment of cognitive function may occur in CAE and CAS patients and warrants further investigation.13 Diffusion-weighted magnetic resonance imaging has been shown to be a highly sensitive tool for the detection of cerebral ischemia, because it enables the visualization of recently ischemic regions as hyperintense areas within minutes of onset.14 During the 24 hours after onset, conventional magnetic resonance imaging is less sensitive than computed tomography for the detection of hemorrhage.15 However, on diffusion-weighted images the core of the acute hemorrhagic lesion is hyperintense and is initially observed at 4 hours after onset, similar to findings in cases of nonhemorrhagic lesion.16 The value of transcranial Doppler detection of emboli has probably been overestimated in the comparison of interventional approaches.17 We therefore used DW MRI to investigate the relevance of intraoperative microemboli to cerebral ischemia and other cerebral lesions such as hemorrhage, in patients who were undergoing CAE and CAS.The purpose of our prospective study was to evaluate the frequency and significance of brain lesions after elective CAE and CAS by using DW MRI and to correlate imaging findings with neuroclinical outcomes.  相似文献   
992.
Background: In patients with acute myocardial infarction (AMI), intraaortic balloon counterpulsation (IABC) may improve cardiac performance, decrease the incidence of recurrent ischemia, and improve survival. Although there have been several reports concerning circulatory maintenance with the IABC, response of the autonomic nervous system to these hemodynamic changes is not clear. Heart rate variability (HRV) analysis has been extensively used to evaluate autonomic modulation of sinus node and to identify patients at risk for an increased cardiac mortality. In this study, we evaluated effects of the IABC on autonomic nervous system functions by HRV analysis. Methods: The study group was composed of 32 consecutive patients (13 female, 19 male aged 61.8 ± 8.8 years) undergoing IABC. Transthoracic echocardiography and 1‐hour Holter recordings for HRV analysis in each IAB pumping mode were obtained. Results: The IABC improved left ventricular diastolic and systolic functions as well as caused an increase in SDNN1, PNN50(1), RMSSD1, and HF1 and a decrease in LF1, LF/HF1, mean heart rate, and the number of ventricular extrasystoles. The improvements in HRV parameters were correlated with some hemodynamic changes such as the increase in MAP and CO during counterpulsation. The only independent factors affecting in‐hospital mortality were the change in LF/HF1 ratio (ΔLF/HF1) and the change in the number of ventricular extrasystole (ΔVES). The decrease in LF/HF1 ≥4.9 decreased the mortality by 1.7‐folds (RR = 0.6, P = 0.04, 95% CI: 0.1–2.3). The decrease in VES ≥27/15 minutes resulted in mortality reduction by 16‐folds (RR = 0.06, P = 0.02, 95% CI: 0.01–0.4). Conclusions: As a result, the IABC, especially in 1:1 support, causes an increase in HRV, decrease in sympathetic overactivity, and improvement in sympathovagal balance besides the favorable hemodynamic changes, and these electrophysiologic changes may explain the role of the IABC in the treatment of ventricular arrhythmias.  相似文献   
993.
BACKGROUND: Previous studies have shown improvement in left ventricular function and development of the reverse remodeling in the left ventricle and left atrium after cardiac resynchronization therapy (CRT). The aim of this study was to investigate the effect of CRT on left atrial appendage (LAA) function and pulmonary venous flow pattern. METHODS: Eighteen patients with systolic heart failure and complete left bundle branch block underwent implantation of biventricular pacemaker devices. In order to follow changes in LAA, transthoracic and transesophageal echocardiographic examinations were performed 1 week before and repeated 1 and 6 months after pacemaker implantation. RESULTS: CRT resulted in significant clinical improvement and decrease in NYHA functional class in 17 patients (94%). Maximum and minimum areas of left atrial appendage (LAAAmax and LAAAmin) decreased, with a concomitant increase in LAA ejection fraction. [LAAAmax: from 4.6+/-2 to 4.2+/-1.8 cm2 at the first (P < 0.001) and to 4.0+/-1.8 cm2 at the sixth month (P < 0.001); LAAAmin: from 2.7+/-1.3 to 2.3+/-1.2 cm2 at the first (P < 0.001) and to 2.2+/-1.2 cm2 at the sixth month (P < 0.001) and LAA ejection fraction: from 41+/-12% to 46+/-10% at the first (P = 0.007) and to 47+/-8% at the sixth month (P = 0.003)]. LAA active emptying and filling flow and pulmonary venous systolic velocities also increased after CRT. The appendage active emptying velocity correlated significantly with left ventricular ejection fraction (r = 0.50, P = 0.002), LAA ejection fraction (r = 0.51, P = 0.002), left atrial maximal volume, LAVmax (r = -0.44, P = 0.007), left atrial minimal volume, LAVmin (r = -0.50, P = 0.002) and pulmonary vein systolic flow velocity (r = 0.33, P = 0.05). CONCLUSION: Treatment of heart failure by CRT results with marked improvements in LAA function and increases pulmonary venous systolic velocity.  相似文献   
994.
We described a patient with familial non-obstructive hypertrophic cardiomyopathy and complete atrioventricular block. A 27-year-old male was admitted to our institution with syncope. Electrocardiography demonstrated complete atrioventricular block. Two-dimensional echocardiography revealed non-obstructive hypertrophic cardiomyopathy. A temporary transvenous ventricular pacemaker was inserted urgently, and subsequently replaced by a permanent dual-chamber pacemaker. Meanwhile, non-obstructive hypertrophic cardiomyopathy was diagnosed in the mother, the aunt and one of the brothers of the patient in the screening of the family, but atrioventricular conduction block was not detected in them. In the electrophysiological study of the mother, inducible ventricular tachycardia was detected. The reason for diversity of the arrhythmias in the members of the same family with hypertrophic cardiomyopathy may be explained by penetrance. The phenotype of the familial hypertrophic cardiomyopathy is influenced by factors varying the penetrance, such as age and gender.  相似文献   
995.
BACKGROUND: There is increasing evidence for the role of nitric oxide (NO) in haemodialysis hypotension but the source of elevated NO is still controversial. Heparin has been reported to enhance NO production by cultured human endothelial cells. The aim of this study was to compare the role of unfractionated heparin and low molecular weight heparin (LMWH, parnaparin) on mean arterial pressure (MAP) and NO production in haemodialysis patients with hypotensive episodes. PATIENTS AND METHODS: Ten maintenance haemodialysis patients with hypotensive episodes were involved in this study. Patients were anticoagulated with heparin for 3 weeks and then switched to parnaparin for 3 weeks. Serum NO levels were analysed before starting dialysis, at the nadir of MAP during a haemodialysis session and at the end of dialysis in the last haemodialysis session of the 3rd week of each anticoagulation treatment. RESULTS: NO levels were 39.4 +/- 13.2 microM at the beginning of haemodialysis, 92.4 +/- 31.4 microM during hypotensive episode and 43.1 +/- 25.1 microM at the end of dialysis with heparin treatment (p < 0.05). In the parnaparin period, NO levels were 47.2 +/- 22.7 microM at the beginning, 80.7 +/- 46.5 microM during the hypotensive episode and 45.8 +/- 23.2 microM at the end of the session (p < 0.05). The percent increase in NO levels during the hypotensive period compared to that at the beginning of haemodialysis with heparin was significantly higher than that with parnaparin (140.2 +/- 50.4 vs. 119.6 +/- 44.8%; p < 0.05). The percent decrease in MAP with heparin use was also significantly higher than with parnaparin use (48.6 +/- 6.4 vs. 39.6 +/- 5.3%; p < 0.05). CONCLUSION: We have observed that MAP decrements and NO increases were less manifest during hypotensive episodes with parnaparin treatment compared to heparin. This difference may be related to differences in endothelial binding capacity, thrombin affinity and/or effects on platelet functions of unfractionated heparin and LMWHs.  相似文献   
996.

Objectives

To determine the prevalence of odontogenic maxillary sinus pathologies and their relationship with periapical pathologies in the maxillary posterior teeth using cone-beam computed tomography (CBCT).

Method

Maxillary posterior CBCT scans of consecutive patients aged 20–77 years were evaluated retrospectively. Patients with at least one maxillary posterior tooth were included. Patients with edentulous maxillae or having one or more maxillary implants were excluded. Finally, 461 CBCT images were evaluated. Demographic data, such as age and sex, and pathologic findings of the right and left maxillary sinuses and adjacent teeth were recorded. Statistical analyses were performed using the Chi square test and binary logistic regression.

Results

The prevalence of right and left odontogenic maxillary sinusitis was 59.5 and 64 %, respectively. Maxillary sinus pathology was more common in males, and there was no relationship with age. Regarding the maxillary sinus pathology, 64 % had mucosal thickening, 19 % had partial opacification, 5 % had total opacification, and 12 % had polypoidal mucosal thickening. Right and left maxillary sinus pathologies were approximately twice as prevalent in patients with periapical pathology in at least one maxillary posterior tooth. Periapical pathologies in the right maxillary first molar and left maxillary first and second molars significantly increased the risk of maxillary sinus pathology with odds ratios of 2.53, 1.83, and 3.12, respectively.

Conclusions

Odontogenic maxillary sinus pathologies were present in >50 % of the study population. Periapical pathologies in the maxillary first and second molar teeth significantly increased maxillary sinus pathologies.
  相似文献   
997.
Although hypo- and hyperthyroid patients have different symptoms in the gastrointestinal tract, the mechanism of thyroid action on the gut remains poorly understood. Thus the aim of this study was to investigate the effect of hypo- and hyperthyroidism on gastric myoelectrical activity, gastric emptying, dyspeptic symptoms. Twenty-two hyperthyroid (median age 45, 15 females) and 11 hypothyroid (median age 42, 10 females) patients were included into the study. Dyspepsia score, hypo- and hyperthyroid symptom scale, abdominal ultrasonography and upper gastrointestinal endoscopy were performed. Gastric myoelectrical activity was measured by electrogastrograpy (EGG) before and after therapy both preprandially and postprandially and compared with age, gender, and body-matched controls (12 for hypothyroid, 15 for hyperthyroid patients). Radionuclide gastric emptying studies were performed with a solid meal. Hypothyroid patients revealed a significant increase in preprandial tachygastria as compared with controls (12.3% vs 4.8%). The percentage of preprandial normal slow waves (2.4–3.7 cpm) was below 70% (dysmotility) in 7 of 11 hypothyroid patients versus 2 of 12 controls (P < 0.05). Hyperthyroid patients revealed a significantly higher preprandial (3.1 vs 2.8) and postprandial (3.4 vs 3) DF when compared with the controls (P < 0.05). A higher percentage of postprandial taschygastria (7.9 vs 0) was present in hyperthyroid patients than in the controls (P < 0.05). The decrease on postprandial EGG power (power ratio < 1) was observed in 7 patients the in hyperthyroid group and 1 in controls (P < 0.05). The percentage of postprandial normal slow waves was below 70% in 10 of 20 hyperthyroid patients vs 1 of 15 controls (P < 0.05). After therapy these differences disappeared in the euthyroid state. The hypo- and hyperthyroid symptom scale correlated to dyspepsia score. Dyspepsia score in hyperthyroidism correlated to power ratios in hyperthyroid patients. We detected some correlations between serum levels of fT3 or fT4 and some EGG parameters in hypo- and hyperthyroidism. Dyspepsia score and hypo- and hyperthyroid symptom scale were improved significantly after therapy in the euthyroid state. In conclusions, we showed gastric dysrhythmia by EGG in both hypo- and hyperthyroid patients. Dyspeptic symptoms correlated to the activity of thyroid disease. After therapy, these findings and dyspeptic symptoms improved in the euthyroid state. Abnormalities of power ratios may be responsible of dyspeptic symptoms in hyperthyroid patients. EGG may be a useful and noninvasive tool for detecting gastric disturbances during hypo- and hyperthyroidism.  相似文献   
998.
999.
Previous studies have revealed the relationship between asthma with obesity and low body mass index (BMI) with chronic obstructive pulmonary disease (COPD). Tumor necrosis factor-alpha (TNF-alpha) is thought to be related with low BMI. The aim of this study was to determine sputum and serum TNF-alpha levels in patients with COPD and asthma and to evaluate whether these parameters had correlation with BMI. Thirty patients with moderate persistent asthma and 26 patients with moderate -severe COPD were included. After BMI values were calculated, sputum was induced by inhalation of hypertonic saline solution and blood was drawn for analysis of serum TNF-alpha levels. There were significant differences in age, serum and sputum TNF-alpha levels between asthma and COPD subjects (Sputum TNF-alpha: asthma; 513 +/- 151 pg/mL-COPD: 333 +/- 126 pg/mL, p< 0.001; Serum TNF-alpha: asthma; 332 +/- 114 pg/mL-COPD: 197 +/- 81 pg/mL, p< 0.001), however there was no difference in BMI (asthma; 28 +/- 5.7-COPD; 26.6 +/- 12.9, p= 0.1). Patients were divided into four categories according to their BMI values as underweight, normal, overweight and obese. In asthmatics; there were 12 (40%) obese and 11 (36%) overweight patients while 9 (34%) of COPD patients were underweight. No significant difference was observed among these four groups according to serum-sputum TNF-alpha and smoking history both in asthmatics and in COPD subjects. While there was no correlation between BMI and serum-sputum TNF-alpha levels, BMI was significantly correlated with both smoking history and duration of disease in COPD patients. As a result, most of the asthmatic patients were described as overweight and obese while no such variation was noted in the COPD patients. The induced sputum TNF-alpha levels has no additional benefit on serum TNF-alpha levels which has already known to be associated with BMI.  相似文献   
1000.
INTRODUCTION: After nonoperative decompression of acute sigmoid volvulus, definitive surgery is necessary because of the high risk of recurrence. However, the optimal surgical technique for this purpose has not been determined. METHODS: We studied 106 consecutive patients (mean age, 60.9 (range, 26–93) years) who underwent emergency resection for acute sigmoid volvulus between 1992 and 2000. No patient underwent preoperative decompression techniques, had the bowel prepared, or received on-table lavage. RESULTS: Depending on the patients condition and the surgeons preference, either primary anastomosis (57 cases) or Hartmanns procedure (49 cases) was performed. The overall mortality rate was 6.6 percent (7/106). The presence of a gangrenous bowel increased the mortality rate to 11 percent. Wound infections were documented in 8 and 12 cases, intra-abdominal abscess occurred in 1 and 7 cases, and subsequent surgery was required in 6 and 5 patients who underwent primary anastomosis and Hartmanns procedure, respectively. There were four cases of anastomotic dehiscence (7 percent) and two cases of stoma revisions (4 percent). The median length of stay was eight days for both those who underwent primary anastomosis (range, 3–27 days) and those who underwent Hartmanns procedure (range, 5–29 days). CONCLUSION: Emergent primary resection of the acute sigmoid volvulus with or without anastomosis is adequate treatment for this emergent surgical problem.  相似文献   
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