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Introduction and objectivesWe assessed the long-term hemodynamic performance of transcatheter heart valve (THV) by paired transthoracic echocardiography (TTE), and the incidence, characteristics and factors associated with THV structural valve degeneration (SVD).MethodsA total of 212 patients who underwent transcatheter aortic valve replacement and had a potential follow-up > 5 years with at least 1 TTE ≥ 1-year postprocedure were included. All patients had a TTE at 1 to 5 years and 36 had another one at 6 to 10 years. SVD was defined as subclinical (increase > 10 mmHg in mean transvalvular gradient +  decrease > 0.3 cm2 in valve area and/or new-onset mild or moderate aortic regurgitation) and clinically relevant (increase > 20 mmHg in mean transvalvular gradient + decrease > 0.6 cm2 in valve area and/or new-onset moderate-to-severe aortic regurgitation). Fifteen patients had a transesophageal echocardiography at the time of SVD diagnosis, and 85 an opportunistic computed tomography examination at 1 (0.5-2) years.ResultsTransvalvular mean gradient increased and valve area decreased over time (P < .01). At 8 years of follow-up, SVD occurred in 30.2% of patients (clinically relevant: 9.3%). Transesophageal echocardiography revealed thickened and reduced-mobility leaflets in 80% and 73% of SVD cases, respectively. No baseline or procedural factors were associated with SVD. THV underexpansion (3.5%) or eccentricity (8.2%) had no impact on valve hemodynamics/SVD at follow-up.ConclusionsA gradual THV hemodynamic deterioration occurred throughout a 10-year period, leading to SVD in ~30% of patients (clinically relevant in < 10%). Leaflet morphology/mobility were frequently impaired in SVD cases, but THV geometry did not influence valve hemodynamics or SVD.  相似文献   
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Hypovitaminosis D has been reported in tropical countries, but this hormone has seldom been studied in Brazil. Our purpose was to study the prevalence of hypovitaminosis D in patients hospitalized in internal medicine wards in Southern Brazil. Possible associated factors were studied. We studied 81 adult patients in early spring. Mean serum 25(OH)D was 12±8.57 ng/mL; hypovitaminosis D was severe (<10 ng/mL) in 27 (33.3%) patients, and moderate (≥10 ng/mL and <20 ng/mL) in 36 (44.5%) patients. Clinical evaluation did not yield any data associated with hypovitaminosis D. Serum 25(OH)D levels of up to 20 ng/mL were associated with decreased mean serum total calcium (p=0.001), ionized calcium (p=0.01), and phosphorus (p=0.044) levels, and increased mean serum PTH level (p=0.001). In a multiple regression model, serum PTH level was independently affected by serum total calcium (p=0.01), phosphorus (p=0.009), and albumin (p=0.009) levels. Hypovitaminosis D patients had lower mean serum albumin levels (p=0.004), and serum 25(OH)D levels were directly correlated to serum albumin levels (p<0.0001). Albumin influenced independently PTH response to hypovitaminosis D; normoalbuminemic hypovitaminosis D patients had higher mean serum PTH than hypoalbuminemic patients. Conclusion: Hypovitaminosis D prevalence was very high in medical inpatients in Southern Brazil, in early spring. Nevertheless, secondary hyperparathyroidism was less intense in hypoalbuminemic hypovitaminosis D patients suggesting that in these patients free serum 25(OH)D was closer to normal.  相似文献   
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Background

Social determinants differ between countries, which is not always considered when adapting health policies and interventions to face inequalities in noncommunicable diseases and their risk factors.

Objectives

The study sought to analyze educational inequalities in controlled blood pressure (CBP), obesity, and smoking in study populations from Chile and the United States in 2 periods, both countries with large social inequalities.

Methods

The study used data from the first and fifth waves of the MESA (Multiethnic Study of Atherosclerosis) cohort, and the 2003 and 2009 to 2010 Chilean National Health Survey (CNHS) survey outcome measures. The study compared cardiovascular risk factors prevalence as well as relative index of inequality (RII) and slope index of inequality (SII) between the 2 samples.

Results

In the CNHS 67.9% and 52.6% of participants had below primary education in 2003 and 2009 to 2010, respectively, compared with 12.3% and 8.1% in the first and fifth waves of the MESA study, respectively. Smoking prevalence was higher and increased in the CNHS compared with the MESA study, concentrated in better-educated women in both years (RII: 0.34; 95% confidence interval [CI]: 0.17 to 0.68; and RII: 0.55; 95% CI: 0.34 to 0.89, respectively). In contrast, smoking decreased over time in the MESA study in all socioeconomic strata, although relative inequalities increased in both sexes (for women, RII: 2.32; 95% CI 1.36 to 3.97; for men, RII: 3.34; 95% CI 2.04 to 5.47). CBP prevalence in both periods was higher in the first and fifth waves of the MESA study (69.7% and 80.2%) compared with the 2003 and 2009 to 2010 CNHS samples (34.2% and 52.3%), but only for the MESA study RII, favoring the better educated, was it significant in both periods and sexes. Obesity inequalities for Chilean women decreased slightly between 2003 and 2009 as prevalence grew in the most educated (RII: 2.21 to 1.68; SII: 0.29 to 0.22, respectively); conversely, they increased for both sexes in the MESA study.

Conclusions

The study findings confirm that patterns and trends in prevalence, and absolute and relative inequalities vary by country, suggesting that context and cultural issues matters.  相似文献   
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Background

The purpose of this study was to determine the prevalence of level IIb metastasis in patients with oral squamous cell carcinomas (OSCCs).

Material and Methods

A prospective analysis of 56 patients with OSCC who underwent surgical treatment of the primary lesion with simultaneous neck dissection was performed. During neck dissection, level IIb lymph nodes were separately removed and processed. Neck dissection was bilateral in 26 patients (46%) and unilateral in 30 patients (54%).

Results

The mean number of nodes found in the level IIb specimens was 4.7 (range: 0-8 nodes). The prevalence of metastasis at level IIb was 0% in pN0 necks and 3.4% in pN+ necks, with an overall prevalence of 1.8%. A significant association between metastasis to level IIb and type of neck dissection was observed. There were no isolated metastases to level IIb without the involvement of other nodes in the remaining neck specimen. Four regional recurrences were observed during follow-up.

Conclusions

Based on our findings, we suggest that dissection of the level IIb region in patients with OSCC may be required only in patients with multilevel neck metastasis or if level IIa metastasis is found intraoperatively. Key words: Oral squamous cell carcinoma, neck dissection, level IIb, metastasis, spinal accessory nerve.  相似文献   
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