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Background

Scientific guidelines consider atrial fibrillation (AF) complicating degenerative mitral regurgitation (DMR) a debated indication for surgery.

Objectives

This study analyzed the prognostic/therapeutic implications of AF at DMR diagnosis and long-term.

Methods

Patients were enrolled in the MIDA (Mitral Regurgitation International Database) registry, which reported the consecutive, multicenter, international experience with DMR due to flail leaflets echocardiographically diagnosed.

Results

Among 2,425 patients (age 67 ± 13 years; 71% male, 67% asymptomatic, ejection fraction 64 ± 10%), 1,646 presented at diagnosis with sinus rhythm (SR), 317 with paroxysmal AD, and 462 with persistent AF. Underlying clinical/instrumental characteristics progressively worsened from SR to paroxysmal to persistent AF. During follow-up, paroxysmal and persistent AF were associated with excess mortality (10-year survival in SR and in paroxysmal and persistent AF was 74 ± 1%, 59 ± 3%, and 46 ± 2%, respectively; p < 0.0001), that persisted 20 years post-diagnosis and independently of all baseline characteristics (p values <0.0001). Surgery (n = 1,889, repair 88%) was associated with better survival versus medical management, regardless of all baseline characteristics and rhythm (adjusted hazard ratio: 0.26; 95% confidence interval: 0.23 to 0.30; p < 0.0001) but post-surgical outcome remained affected by AF (10-year post-surgical survival in SR and in paroxysmal and persistent AF was 82 ± 1%, 70 ± 4%, and 57 ± 3%, respectively; p < 0.0001).

Conclusions

AF is a frequent occurrence at DMR diagnosis. Although AF is associated with older age and more severe presentation of DMR, it is independently associated with excess mortality long-term after diagnosis. Surgery is followed by improved survival in each cardiac rhythm subset, but persistence of excess risk is observed for each type of AF. Our study indicates that detection of AF, even paroxysmal, should trigger prompt consideration for surgery.  相似文献   
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Objectives

Meningococcal C (MenC) vaccination was introduced in the French vaccination calendar in 2010 to reduce the incidence of invasive meningococcal C disease (IMD C), mainly through herd immunity. The Vaccinoscopie survey helps follow vaccination coverage rates (VCRs) of children.

Methods

This annual survey is based on a self-administered online questionnaire. In 2017, 4500 mothers of children completed the questionnaire and reported all vaccinations recorded in their child's health record.

Results

MenC vaccination was deemed indispensable or useful by 77% to 84% of mothers. The main barrier mentioned by mothers considering the vaccination useless/not very useful, was fear of adverse effects. VCR was estimated at 77% among 24-35-month-old infants, 79% among 6-year-old children, and 50% among 14-15-year-old adolescents. VCR strongly varied depending on the physician's advice for vaccination and on the type of follow-up. Six months after publication of the new French vaccine calendar in April 2017, with a MenC vaccine recommendation for all 5-month-old infants, 43% of infants had received a dose at 6 months of age.

Conclusions

VCRs are insufficient to reach herd immunity. Between 2011 and 2017 more than 100 deaths could have been avoided in France if optimal VCRs had been achieved. Faced with this vaccine strategy failure, the new vaccine recommendation at 5 months of age seems well-accepted. This recommendation and the implementation of infant mandatory vaccination in 2018 should have a major impact on IMD C incidence in this age group.  相似文献   
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Melanin-concentrating hormone (MCH) is a ubiquitous vertebrate neuropeptide predominantly synthesized by neurons of the diencephalon that can act through two G protein-coupled receptors, called MCHR1 and MCHR2. The expression of Mchr1 has been investigated in both rats and mice, but its synthesis remains poorly described. After identifying an antibody that detects MCHR1 with high specificity, we employed immunohistochemistry to map the distribution of MCHR1 in the CNS of rats and mice. Multiple neurochemical markers were also employed to characterize some of the neuronal populations that synthesize MCHR1. Our results show that MCHR1 is abundantly found in a subcellular structure called the primary cilium, which has been associated, among other functions, with the detection of free neurochemical messengers present in the extracellular space. Ciliary MCHR1 was found in a wide range of areas, including the olfactory bulb, cortical mantle, striatum, hippocampal formation, amygdala, midline thalamic nuclei, periventricular hypothalamic nuclei, midbrain areas, and in the spinal cord. No differences were observed between male and female mice, and interspecies differences were found in the caudate-putamen nucleus and the subgranular zone. Ciliary MCHR1 was found in close association with several neurochemical markers, including tyrosine hydroxylase, calretinin, kisspeptin, estrogen receptor, oxytocin, vasopressin, and corticotropin-releasing factor. Given the role of neuronal primary cilia in sensing free neurochemical messengers in the extracellular fluid, the widespread distribution of ciliary MCHR1, and the diverse neurochemical populations who synthesize MCHR1, our data indicate that nonsynaptic communication plays a prominent role in the normal function of the MCH system.  相似文献   
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