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91.

Objectives

The aim of this study was to further evaluate clinical outcomes in patients with and without PCS.

Background

Prior cardiac surgery (PCS) is associated with increased surgical risk and post-operative complications following surgical aortic valve replacement (SAVR), but whether this risk is similar in transcatheter aortic valve replacement (TAVR) is unclear.

Methods

In the PARTNER 2A (Placement of Aortic Transcatheter Valve) trial, 2,032 patients with severe aortic stenosis at intermediate surgical risk were randomized to TAVR with the SAPIEN XT valve or SAVR. Adverse clinical outcomes at 30 days and 2 years were compared using Kaplan-Meier event rates and multivariate Cox proportional hazards regression models. The primary endpoint of the PARTNER 2 trial was all-cause death and disabling stroke.

Results

Five hundred nine patients (25.1%) had PCS, mostly (98.2%) coronary artery bypass grafting. There were no significant differences between TAVR and SAVR in patients with or without PCS in the rates of the primary endpoint at 30 days or 2 years. Nevertheless, an interaction was observed between PCS and treatment arm; whereas no-PCS patients treated with TAVR had higher rates of 30-day major vascular complications than patients treated with SAVR (adjusted hazard ratio: 2.66; 95% confidence interval: 1.68 to 4.22), the opposite was true for patients with PCS (adjusted hazard ratio: 0.27; 95% confidence interval: 0.11 to 0.66) (pinteraction <0.0001). A similar interaction was observed for life-threatening or disabling bleeding.

Conclusions

In the PARTNER 2A trial of intermediate-risk patients with severe aortic stenosis undergoing SAVR versus TAVR, the relative risk for 2-year adverse clinical outcomes was similar between TAVR and SAVR in patients with or without PCS.  相似文献   
92.
Thrombophilia was implicated in the development of pregnancy complications, including recurrent idiopathic pregnancy loss, and is aggravated in women who are carriers of factor V G1691A (FV Leiden) and prothrombin (PRT) G20210A single-nucleotide polymorphisms (SNPs). Previous studies examined the role of FV-Leiden and PRT G20210A in recurrent pregnancy loss with conflicting results. Here we examined the prevalence of FV Leiden and PRT G20210A SNPs, in 200 women with 3 or more consecutive early (n = 87), late (n = 41), or early-late (n = 72) recurrent pregnancy losses, and 200 age-matched fertile parous control women. APC resistance (APCR) was detected functionally (measuring the activated clotting time triggered by activated factor X in presence of a fixed amount of purified APC), and FV-Leiden and PRT G20210A genotypes were assessed by PCR. The frequency of the mutant FV (0.1400 vs. 0.0276; P < 0.001) but not PRT 20210 (0.0100 vs. 0.0225; P = 0.159) allele was higher in patients than controls, respectively. APC resistance with factor V Leiden was seen in 27% of patients compared to 11.5% of controls, while APC resistance without factor V Leiden was seen in 12.5% of patients compared to 9.5% of controls. Regression analysis demonstrated that the significant predictors for early abortion was FV Leiden; those for late abortion were oral contraceptive, APCR, and FV Leiden; and predictors for early-late abortions were oral contraceptives, obesity, FV Leiden, and smoking. APC resistance and FV Leiden, as well as combination of both, are common thrombotic defects seen in women with idiopathic recurrent pregnancy loss, thus testing for these is recommended in women who have experienced recurrent miscarriages.  相似文献   
93.

Background

Emergency and transport ventilators use in the prehospital field is not well described. This study examines trends of ventilator use by EMS agencies during 911 calls in the United States and identifies factors associated with this use.

Methods

This retrospective study used four consecutive releases of the US National Emergency Medical Services Information System (NEMSIS) public research dataset (2011–2014) to describe scene EMS activations (911 calls) with and without reported ventilator use.

Results

Ventilator use was reported in 260,663 out of 28,221,321 EMS 911 scene activations (0.9%). Patients with ventilator use were older (mean age 67 ± 18 years), nearly half were males (49.2%), mostly in urban areas (80.2%) and cared for by advanced life support (ALS) EMS services (89.5%). CPAP mode of ventilation was most common (71.6%).“Breathing problem” was the most common dispatch complaint for EMS activations with ventilator use (63.9%). Common provider impression categories included “respiratory distress” (72.5%), “cardiac rhythm disturbance” (4.6%), “altered level of consciousness” (4.3%) and “cardiac arrest”(4.0%).Ventilator use was consistently higher at the Specialty Care Transport (SCT) and Air Medical Transport (AMT) service levels and increased over the study period for both suburban and rural EMS activations. Significant factors for ventilator use included demographic characteristics, EMS agency type, specific complaints, provider's primary impressions and condition codes.

Conclusions

Providers at different EMS levels use ventilators during 911 scene calls in the US. Training of prehospital providers on ventilation technology is needed. The benefit and effectiveness of this intervention remain to be assessed.  相似文献   
94.
Objective. Studies on allergic diseases remain scarce in Lebanon. The aim of the present study was to determine prevalence and characteristics of asthma, allergic rhinitis and eczema among Lebanese school children. Methods. The study was cross-sectional in design performed on a convenient sample of 3,115 students (13–14 yr) selected from 13 schools in 5 Lebanese provinces. Students were asked to complete the Arabic version of the International Study of Asthma and Allergies in Childhood questionnaire. Logistic regression was performed to assess the characteristics of having asthma, allergic rhinitis and eczema in the past year. Results. The prevalence of ever having asthma, rhinitis and eczema was 8.3%, 45.2% and 12.8% respectively, while the prevalence of the symptoms of these diseases in the past year was 24.1%, 38.6% and 20.9%, respectively. Residing in the South and the North provinces of Lebanon and living in a busy area increased the likelihood of developing asthma and rhinitis. Higher rates of asthma and eczema, however, was noted among students going to private schools (Odds Ratio (OR) = 1.6, 95% confidence interval (CI): 1.3–2.1 and OR = 1.3, 95% CI: 1.0–1.7, respectively). Passive smoking was significantly associated with asthma only (OR = 1.3, 95% CI: 1.1–1.7). In addition to the above, the odds of having any of the three outcomes increases to at least 2.4-fold when accompanied by another allergic disease. Conclusions. Allergic diseases are highly prevalent in Lebanon and are catching up with the rates of developed countries. Moreover, the role of each of the three diseases in the existence of the other two had the greatest impact on their prevalence.  相似文献   
95.
Endoscopic vein harvesting (EVH) is becoming common for the patients undergoing coronary artery bypass grafting. Using carbon dioxide insufflations during the vein harvest can produce rare but catastrophic CO(2) embolism. We report a case of massive right atrial CO(2) embolism due to femoral vein injury which occurred during the performance of a routine EVH procedure.  相似文献   
96.
BACKGROUND: The aim of the study was to evaluate the outcomes and patterns of failure in patients with metastatic carcinoma to cervical lymph nodes from an unknown head and neck primary origin, who were treated curatively with radiotherapy, with or without neck dissection. METHODS: The study included 61 patients referred to the McGill University Hospital Centers from 1987 to 2002. The median age was 57 years, with male to female ratio of 4:1. Distribution of patients by N status was as follows: N1, 16 patients (26%); N2a, 18 (30%); N2b, 13 (22%); N2c, 7 (11%); and N3, 7 (11%). Twenty patients underwent neck dissection (11 radical, 9 functional) and 41 patients had biopsy (9 fine-needle aspiration and 32 excisional biopsy). All patients received radiotherapy. The median dose to the involved node(s) was 64 Gy, and 60 Gy to the rest of the neck. Treatment of the neck was bilateral in 50 patients (82%) and ipsilateral in 11 (18%). The minimum duration of the follow-up was 12 months, with the median of 32 months. RESULTS: The 5- and 8-year overall survival for the whole population was 79% and 67%, respectively. There was no statistically significant difference in the 8-year actuarial overall survival (64.8% and 67.6%, respectively, p = .64) and local relapse-free survival (75% vs 74.5%, respectively, p = .57), among patients who had biopsy versus those who had neck dissection. CONCLUSION: In our experience, definitive radiotherapy to the neck and the potential mucosal sites, whether preceded by neck dissection or not, is effective to achieve a good local control rate in the unknown primary cancer of the head and neck. The indication for neck dissection, in particular for early nodal stage, is controversial.  相似文献   
97.
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99.
Deletions of chromosome 1p36 are one of the most frequently encountered subtelomeric alterations. Clinical features of monosomy 1p36 include neurocognitive impairment, hearing loss, seizures, cardiac defects, and characteristic facial features. The majority of cases have occurred sporadically, implying that genomic instability plays a role in the prevalence of the syndrome. Here, we report two siblings with mild phenotypic features of the deletion syndrome, including developmental delay, hearing loss, and left ventricular non-compaction (LVNC). Microarray analysis using bacterial artificial chromosome and oligonucleotide microarrays indicated the deletions were identical, suggesting germline mosaicism. Parental phenotypes were normal, and analysis by fluorescence in situ hybridization (FISH) did not show mosaicism. These small interstitial deletions were not detectable by conventional subtelomeric FISH analysis. To investigate the mechanism of deletion further, the breakpoints were cloned and sequenced, demonstrating the presence of a complex rearrangement. Sequence analysis of genes in the deletion interval did not reveal any mutations on the intact homologue that may have contributed to the LVNC seen in both children. This is the first report of apparent germline mosaicism for this disorder. Thus, our findings have important implications for diagnostic approaches and for recurrence risk counseling in families with a child with monosomy 1p36. In addition, our results further refine the minimal critical region for LVNC and hearing loss.  相似文献   
100.
Genomic disorders contribute significantly to genetic disease and, as detection methods improve, greater numbers are being defined. Paralogous low copy repeats (LCRs) mediate many of the chromosomal rearrangements that underlie these disorders, predisposing chromosomes to recombination errors. Deletions of proximal 22q11.2 comprise the most frequently occurring microdeletion syndrome, DiGeorge/Velocardiofacial syndrome (DGS/VCFS), in which most breakpoints have been localized to a 3 Mb region containing four large LCRs. Immediately distal to this region, there are another four related but smaller LCRs that have not been characterized extensively. We used paralog-specific primers and long-range PCR to clone, sequence, and examine the distal deletion breakpoints from two patients with de novo deletions mapping to these distal LCRs. Our results present definitive evidence of the direct involvement of LCRs in 22q11 deletions and map both breakpoints to the BCRL module, common to most 22q11 LCRs, suggesting a potential region for LCR-mediated rearrangement both in the distal LCRs and in the DGS interval. These are the first reported cases of distal 22q11 deletions in which breakpoints have been characterized at the nucleotide level within LCRs, confirming that distal 22q11 LCRs can and do mediate rearrangements leading to genomic disorders.  相似文献   
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