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21.
Background Differences between the updated versions of the Brazilian Guideline on Dyslipidemias and the American Heart Association (AHA)/American College of Cardiology (ACC) Cholesterol Guideline regarding cardiovascular risk stratification and statin eligibility are unknown.Objectives To compare cardiovascular risk categorization and statin eligibility based on the Brazilian guideline with those based on the AHA/ACC guideline in primary prevention patients.Methods We retrospectively analyzed individuals aged 40-74 years without high-risk conditions, with LDL-c 70 to < 190 mg/dL, not on lipid-lowering drugs, who underwent routine clinical assessment. Cardiovascular risk was stratified according to the Brazilian and the AHA/ACC guidelines. Subjects were considered eligible for statin therapy if LDL-c was at least 30 mg/dL above the target for the cardiovascular risk (Brazilian guideline) or the 10-year atherosclerotic cardiovascular disease risk was ≥7.5% (AHA/ACC guideline). A p-value < 0.05 was considered statistically significant.Results The study sample consisted of 18,525 subjects (69% male, age 48 ± 6 years). Among subjects considered at intermediate or high risk by the Brazilian guideline, over 80% would be in a lower risk category by the AHA/ACC guideline. Among men, 45% and 16% would be statin eligible by the Brazilian and the AHA/ACC guidelines criteria, respectively (p < 0.001). Among women, the respective proportions would be 16% and 1% (p < 0.001). Eighty-two percent of women and 57% of men eligible for statins based on the Brazilian guideline criterion would not be eligible according to the AHA/ACC guideline criterion.Conclusions Compared with the AHA/ACC guideline, the Brazilian guideline classifies a larger proportion of primary prevention patients into higher-risk categories and substantially increases statin eligibility. (Arq Bras Cardiol. 2020; 115(3):440-449)  相似文献   
22.

Objectives:

To perform a systematic review with meta-analysis to answer the question: is the cervical vertebrae maturation index (CVMI) effective to replace hand–wrist radiograph (gold standard) in determining the pubertal growth spurt in patients undergoing bone growth?

Methods:

A search in three databases was performed, in which studies were selected that compared one of the two main assessment methods for cervical vertebrae (Hassel B, Farman AG. Skeletal maturation evaluation using cervical vertebrae. Am J Orthod Dentofacial Orthop 1995; 107: 58–66, or Baccetti T, Franchi L, McNamara JA Jr. An improved version of the cervical vertebral maturation (CVM) method for the assessment of mandibular growth. Angle Orthod 2002; 72: 316–23) to a carpal assessment method. The main methodological data from each of the texts were collected and tabulated after. Later, the meta-analysis of the correlation coefficients obtained was performed.

Results:

19 articles were selected from an initial 206 articles collected. Regardless of the method used, the results of the meta-analysis showed that every article selected presented a positive correlation between skeletal maturation assessment performed by cervical vertebrae and carpal methods, with discrepancy of values between genders indicating higher correlation for the female gender (0.925; 0.878) than for the male (0.879; 0.842). When the assessment was performed without gender separation, correlation was significant (0.592; 0.688) but lower in the cases when genders were separated.

Conclusions:

With the results of this meta-analysis, it is safe to affirm that both CVMIs used in the present study are reliable to replace the hand–wrist radiograph in predicting the pubertal growth spurt, considering that the highest values were found in female samples, especially in the method by Hassel and Farman.  相似文献   
23.

Purpose

This study aims to compare the effects of a mandibular advancement device (MAD) with continuous positive airway pressure (CPAP) treatment for obstructive sleep apnea (OSA) on blood pressure (BP), oxidative stress, and heart rate variability (HRV) in a randomized, crossed-over, single-blind, and controlled trial.

Methods

Twenty-nine moderate-to-severe adult OSA patients underwent MAD, CPAP, and placebo oral appliance treatment. Polysomnography, Epworth sleepiness scale, 24-h ambulatory BP monitoring, oxidative stress parameters (malondialdehyde, catalase, superoxide dismutase, vitamins C, E, B6, B12, folate, homocysteine, uric acid), and HRV were assessed at baseline and after 1 month of each treatment. Diaries were used to evaluate compliance for devices and a pressure–time meter for CPAP.

Results

Both active treatments resulted in decreases in apnea and hypopnea index and Epworth sleepiness scale; CPAP showed a greater effect. Frequency of diastolic BP dipping was higher in the MAD group compared with the CPAP group. A significant drop from baseline levels for catalase activity was observed after MAD. For HRV, there was a significant decrease in total power at night with CPAP and MAD compared with POA, and a decrease in index of sleep autonomic variation with MAD compared with baseline levels. Compliance rates were higher with MAD rather than CPAP.

Conclusions

Even though CPAP proved to be more effective at attenuating OSA, better compliance with MAD favored the reduction of one of the enzymes which participates in oxidative stress and better autonomic modulation during sleep.  相似文献   
24.

Background

The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea.

Objective

To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample.

Methods

Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart®) system.

Results

A total of 767 participants (461 men) with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat) was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001). After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia.

Conclusion

Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.  相似文献   
25.

OBJECTIVE:

There are several treatments for obstructive sleep apnea syndrome, such as weight loss, use of an oral appliance and continuous positive airway pressure, that can be used to reduce the signs and symptoms of obstructive sleep apnea syndrome. Few studies have evaluated the effectiveness of a physical training program compared with other treatments. The aim of this study was to assess the effects of physical exercise on subjective and objective sleep parameters, quality of life and mood in obstructive sleep apnea patients and to compare these effects with the effects of continuous positive airway pressure and oral appliance treatments.

METHODS:

Male patients with moderate to severe obstructive sleep apnea and body mass indices less than 30 kg/m2 were randomly assigned to three groups: continuous positive airway pressure (n = 9), oral appliance (n = 9) and physical exercise (n = 7). Polysomnographic recordings, blood samples and daytime sleepiness measurements were obtained prior to and after two months of physical exercise or treatment with continuous positive airway pressure or an oral appliance. Clinicaltrials.gov: NCT01289392

RESULTS:

After treatment with continuous positive airway pressure or an oral appliance, the patients presented with a significant reduction in the apnea-hypopnea index. We did not observe changes in the sleep parameters studied in the physical exercise group. However, this group presented reductions in the following parameters: T leukocytes, very-low-density lipoprotein and triglycerides. Two months of exercise training also had a positive impact on subjective daytime sleepiness.

CONCLUSIONS:

Our results suggest that isolated physical exercise training was able to modify only subjective daytime sleepiness and some blood measures. Continuous positive airway pressure and oral appliances modified the apnea-hypopnea index.  相似文献   
26.
27.

Introduction

In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench.

Objective

To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21 - 751 and 21 AJ - 501 models) exposed to a steady flow regime, on four distinct sections, three downstream and one upstream.

Methods

To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min. ) and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements.

Results

It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found.

Conclusions

Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21 - 751 (RegentTM) is superior to the 21 AJ - 501 model (Master Series). Based on the results, future studies can choose to focus on specific regions of the these valves.  相似文献   
28.
29.
The aim of this study was to evaluate whether there is a positive correlation between the width of the zone of gingival keratinized tissue and its thickness. Maxillary right canines, lateral incisors, and central incisors of 60 patients (30 men, 30 women) between the ages of 20 and 35 years were examined. Using an endodontic spacer with a rubber cursor and a digital caliper of 0.01-mm resolution, the values of the width of the zone of gingival keratinized tissue and gingival thickness were obtained. It was observed that the lateral incisor has the largest mean zone of gingival keratinized tissue (5.54 ± 1.09 mm), followed by the central incisor (4.62 ± 1.02 mm) and canine (4.32 ± 1.33 mm). The mean gingival thickness was greater in the central incisor (1.17 ± 0.20 mm), followed by the lateral incisor (1.04 ± 0.24 mm) and canine (0.87 ± 0.27 mm). No statistically significant difference was verified for the mean width of the zone of gingival keratinized tissue and gingival thickness between men and women. A positive correlation between gingival thickness and width of the zone of gingival keratinized tissue was observed in the maxillary canine (Pearson r = 0.398, P < .05), lateral incisor (Pearson r = 0.369, P < .05), and central incisor (Pearson r = 0.492, P < .05). In patients 20 to 35 years of age, there was a positive correlation between gingival thickness and width of the zone of gingival keratinized tissue for the maxillary right canine, lateral incisor, and central incisor.  相似文献   
30.

Introduction

Although impaired pulmonary function and respiratory sleep disorders are described as responsible for increased mortality in acromegalic patients, little is known about the tracheal abnormalities in this group of patients. Thus, the objectives of this study were to describe the tracheal structural abnormalities and correlate these changes with the respiratory function and clinical data of acromegalic patients.

Material and methods

This is a cross-sectional study that was carried out at two university hospitals. Twenty acromegalic patients underwent spirometry, forced oscillation technique, and computed tomography (CT) assessments. Dyspnea and daytime sleepiness were assessed using the Modified Medical Research Council (MMRC) scale and the Epworth Sleepiness Scale (ESS), respectively. Forty matched subjects served as controls.

Results

The acromegalic patients exhibited larger median ratios between forced expiratory flow and forced inspiratory flow at 50% of the forced vital capacity (FEF50%/FIF50%) (2.05 vs. 1.06, p = 0.0001) compared with healthy volunteers. In the CT analysis, acromegalic patients exhibited larger median differences between their cervical and thoracic tracheal diameters (Δ tracheal diameters) (3 vs. 1 mm; p = 0.003). An association was found between FEF50%/FIF50% and the following variables: mean resistance (Rm), cervical tracheal diameter, and Δ tracheal diameters. Rm also exhibited a negative correlation with cervical tracheal diameter. Neither the MMRC scale nor the ESS exhibited any significant correlation with large airway obstruction (LAO) indices or with the measured tracheal diameters.

Conclusions

Acromegalic patients have tracheal structural abnormalities which are associated with functional indicators of LAO but not with clinical data.  相似文献   
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