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131.
Objectives: Left ventricular (LV) systolic synchrony, defined as simultaneous peak contractions of corresponding cardiac segments, is well documented to be impaired in hypertension but its effect on LV function is not clear. The aim of this study was to assess the impacts of LV systolic dyssynchrony on LV function in newly diagnosed hypertensives. Methods: Forty-eight newly diagnosed hypertensive patients and 33 controls were enrolled. All study population underwent a comprehensive echocardiographic evaluation including tissue synchrony imaging. The time to regional peak systolic tissue velocity (Ts) in LV by 12 segmental models was measured and two parameters of systolic dyssynchrony were computed. Results: Baseline demographic characteristics were similar in both study groups. Dyssynchrony parameters prolonged in newly diagnosed hypertensive patients compared to controls: the standard deviation (SD) of 12 LV segments Ts (40.2 ± 21 vs. 26.2 ± 13.4, P = 0.003); the maximal difference in Ts between any 2 of 12 LV segments (123.3 ± 61.5 vs. 79.8 ± 37.9, P = 0.001). In multivariable analysis, Ts-SD-12 was found to be an independent predictor for systolic function (β=-0.29, P = 0.008). But, both diastolic and global functions were not independently related to Ts-SD-12. Conclusion: LV synchronization is impaired in newly diagnosed hypertensive patients. LV dyssynchrony is one of the independent predictors of systolic function in hypertensive patients.  相似文献   
132.
133.
Purpose: To evaluate whether patent foramen ovale (PFO) is a contributing factor to hypoxia in patients with chronic obstructive pulmonary disease (COPD). Methods: Twenty‐one patients over 40 years of age with mild COPD (Forced expiratory volume (FEV1)/Forced Vital Capacity (FVC): > 50%) who had hypoxia (PO2 < 80 mmHg, SaO2 < 95%) that could not be explained by COPD alone were included in this study. Arterial oxygen pressures (PO2) and arterial oxygen saturations (SaO2) were recorded from laboratory evaluations of arterial blood gases. Respiratory function tests were performed to analyze the degree of COPD. Standard and contrast echocardiography was used to calculate pulmonary artery pressure (PAP) levels and to determine patients with a PFO. Results: The mean age of the patients was 64 ± 12 years. Four patients (19%) had a PFO. The mean PO2, mean SaO2, and mean PAP levels were 57.4 ± 6.8 mmHg, 90 ± 3.2%, and 33.8 ± 5.4 mmHg, respectively, in patients without PFO. The mean PO2, mean SaO2, and mean PAP levels were 46.5 ± 13.7 mmHg, 79.3 ± 12.8%, and 42.5 ± 6.5 mmHg, respectively, in patients with PFO. There were no statistically significant differences noted between the two groups in the PO2 levels (P = 0.172) and SaO2 levels (P = 0.065). A comparison of the PAP levels revealed a statistically significant difference between the two groups, with values that were more elevated in the PFO group than in the non‐PFO group (P = 0.031). Conclusion: This study demonstrated that PFO is not a contributing factor to deep hypoxia in COPD patients with lower PO2 and SaO2 levels; however, higher PAP levels were detected in patients with a PFO. Further studies involving a larger number of patients are needed to be conclusive. (Echocardiography 2010;27:687‐690)  相似文献   
134.
Background: The widespread use of percutaneous mitral commissurotomy (PMC) has led to an increase in restenosis cases. The data regarding follow‐up results of repeat PMC are quite limited. The aim of this retrospective analysis is to evaluate the immediate and midterm results of the second PMC, in patients with symptomatic mitral restenosis after a succesful first procedure. Methods: Twenty patients (95% female, mean age 37 ± 4 years) who have undergone a second PMC, 6.3 ± 2.5 years after a first successful intervention built the study group. All were in sinus rhythm, with a mean Wilkins score of 8.5 ± 1.2. Results: The valve area increased from 1.2 ± 0.2 to 1.9 ± 0.2 cm2 and mean gradient decreased from 10.5 ± 3.4 to 6.1 ± 1.1 mmHg. There were no complications except for a transient embolic event without sequela (5%) and two cases (10%) of severe mitral regurgitation. The immediate success rate was 90%. The mean follow‐up was 70 ± 29 months (36–156 months). The 5‐year restenosis and intervention (repeat PMC or valve replacement) rates were 9.1 ± 5.2% and 3.6 ± 3.3%, respectively. The intervention free 5‐year survival in good functional capacity (New York Heart Association [NYHA] I–II) was 95.1 ± 5.5% and restenosis and intervention free 5‐year survival with good functional capacity was 89.7 ± 6.8%. Conclusions: Although from a limited number of selected patients, these findings indicate that repeat PMC is a safe and effective method, with follow‐up results similar to a first intervention and should be considered as the first therapeutic option in suitable patients. (Echocardiography 2010;27:765‐769)  相似文献   
135.

Purpose  

High-energy photons are most commonly used in radiotherapy to treat cancer. Wedge filters are required to obtain homogeneous dose distribution in the patient. Different wedge filter types create different surface doses. In this study, the effect of the virtual and physical wedge filters on the surface and build-up region doses was examined for 6- and 18-MV high-energy photon beams.  相似文献   
136.
Objective: The purpose of the current study was to investigate the possible effects of phototherapy on bone status of term infants evaluated by measurement of tibial bone speed of sound (SOS).

Materials and methods: The phototherapy group (n?=?30) consisted of children who had undergone phototherapy for at least 24?h and the control group (n?=?30) comprised children who had not received phototherapy. Blood samples were obtained from all infants for serum calcium, phosphorus, magnesium, alkaline phosphatase, parathyroid hormone and vitamin D concentrations. The left tibial quantitative ultrasound (QUS) measurements were performed using a commercial device.

Results: There was no statistically significant difference between phototherapy-exposed and nonexposed infants in terms of Ca, P, ALP, PTH and vitamin D levels. Comparison of bone SOS between the phototherapy-exposed and control group revealed no statistically difference. Also, no significant difference in Z-score for SOS was observed between those with or without exposure.

Conclusion: The data of our study indicate that phototherapy treatment has no impact on bone status in the hyperbilirubinemic infants. Although there is no statistically significant evidence of an excess risk of bone damage following phototherapy, studies with larger sample sizes and longer duration of follow-up are needed to gain a better understanding of its effects.  相似文献   
137.

Aim

Optimization of coronary sinus (CS) lead position to the latest activated left ventricular (LV) area is important to increase cardiac resynchronization therapy (CRT) response. We aimed to detect the relationship between coronary sinus lead delay index (CSDI) and echocardiographic, electrocardiographic response to CRT treatment.

Methods

We prospectively included 137 consecutive patients with heart failure (HF) diagnosis, QRS ≥ 120 ms, left bundle branch block (LBBB), New York Heart Association score (NYHA) II–IV, LV ejection fraction (LVEF) <35% and scheduled for CRT (84 male, 53 female; mean age 65.1 ± 10.1 years). Echocardiographic CRT response was defined as ≥15% reduction in LV end‐systolic volume (LVESV). CS lead sensing delay was calculated as the time interval from the onset of surface QRS wave to the onset of depolarization wave recorded from the CS lead by using the CS pacing lead as a bipolar electrode. CSDI was calculated by dividing the CS lead sensing delay by the QRS duration.

Results

LVESV reduction was associated with baseline QRS width (r = .257, p = .002), QRS narrowing (r = .396, p < .001), CSDI (r = .357, p < .001), and NT‐proBNP (r = ?0.213, p = .022) in bivariate analysis. In logistic regression analysis, CSDI was found to be only independent parameter for predicting significant LVESV reduction (Beta = 0.318, p < .001). CSDI was also found to be significantly associated with LVEF increase (r = .244, p = .004) and QRS narrowing (r = .178, p = .046).

Conclusion

CSDI may be used as a marker to predict the favorable response to CRT. It may be useful to integrate CSDI to CRT implantation procedure in order to minimize nonresponders.
  相似文献   
138.
Oxidative stress was related with carpal tunnel syndrome (CTS). We aimed to clarify the associations between glutathione S-transferase (GST)M1, GSTT1 and GSTP1-Ile105Val polymorphisms and CTS. One hundred-forty patients with CTS and 97 healthy controls were enrolled in this study. Tinel and Phalen signs were noted as positive or negative. Functional and clinical status of patients was evaluated by the Boston Questionnaire. The intensity of hand and/or wrist pain was evaluated on 10 cm visual analog scale (VAS). We applied the polymerase chain reaction (PCR) to determine the polymorphisms of the GSTM1 and GSTT1 and the PCR-restriction fragment length polymorphism method for detecting the GSTP1-Ile105Val polymorphism. The M1 null genotype was significantly higher in patients with CTS compared to healthy controls, and the M1 null genotype seemed to increase the risk of CTS approximately two-fold (P?=?0.011; odds ratio (OR)?=?1.98; 95 % confidence interval (CI) 1.17–3.36). The M1 null, T1 present combined genotype was significantly higher in patients with CTS compared to healthy controls (P?=?0.043); however, it seemed not to increase the risk of CTS (P?=?0.14; OR?=?0.62; 95 % CI 0.33–1.76). We found significantly higher levels of the VAS, Boston Symptom Severity Scale and Phalen sign in patients with the Ile/Val or the Val/Val genotypes compared to those in patients with the Ile/Ile genotype (P?=?0.003, 0.004 and 0.044, respectively). We proposed that genes involved in the protection from oxidative stress may influence the susceptibility, clinical and functional status of CTS. The GSTM1 null genotype may be related with the development of CTS, whereas the Val allele of GSTP1-Ile105Val polymorphism may be associated with worse functional and clinical status in CTS.  相似文献   
139.
Prayer is one kind of worship that is composed of repetitive action during praying in Islam. The prayer is performed five times a day, every Friday, bairams and death ceremonies. The aim of this study is to search the role of this repetitive action on knee, hip osteoarthritis and osteoporosis. Forty-six patients who had been performing the prayer at least for 10 years, and 40 patients who had not performed the prayer, were included in this prospective study. Each patient was evaluated with standard questionnaire form, joint examination was done and various laboratory parameters were studied. Anterior–posterior radiography of the pelvis and weight-bearing knees of each patient were examined. Each film was evaluated by two investigators separately and first scored by using Kellgren and Lawrence (K&L) scale, then the width of the joint space of hips and knees were measured directly using a steel ruler and recorded to the nearest half millimeter. Bone mineral density (BMD) of lumbar spine and femur was measured. Patients having Heberden’s nodes, Bouchard’s nodes, and carpometacarpal disease were frequent in worshiper group. Joint space width measurements and assessment according to K&L scale did not differ between worshipers and non-worshipers. BMD of lumbar spine was decreased in worshipers and also decreased with patients having Heberden’s nodes, Bouchard’s nodes, female gender and age. Prayer has no effect on knee and hip osteoarthritis, and may be related with hand osteoarthritis. It seems to have negative effect on lumbar BMD, but further investigations are needed.  相似文献   
140.
In this report, we describe an unusual case of right ventricular outflow tract (RVOT) tachycardia with episodes of repetitive monomorphic ventricular tachycardia (VT), paroxysmal sustained VT and incessant monomorphic VT of the same morphology. Diltiazem, adenosine, or metoprolol failed to interrupt these arrhythmias. However, administration of intravenous propafenone completely eliminated all ventricular ectopic activity. Electrophysiologic study performed off propafenone showed that the ventricular ectopic activity originated from a single locus at the anterior wall of the RVOT. Two radiofrequency applications at this site resulted in complete elimination of ventricular ectopic activity.  相似文献   
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