Obstructive Sleep Apnea as a Risk Factor for Atrial Fibrillation: A Meta-Analysis.

OBJECTIVES: To conducted a meta-analysis assessing the relationship between Obstructive Sleep Apnea (OSA) and the risk of Atrial Fibrillation (AF). METHODS: We searched PUBMED, Medline, and Cochrane Library using the keywords "atrial fibrillation", "obstructive sleep apnea" and "sleep disordered breathing (SDB)". All subjects included had established diagnosis of OSA/SDB. We then compared the occurrence of AF versus no AF. Analysis done with Comprehensive Meta-Analysis package V3 (Biostat, USA). RESULTS: A total of 579 results were generated. Duplicates were removed and 372 records were excluded based on irrelevant abstracts, titles, study design not consistent with the stated outcome, or full-text unavailable. Twelve studies meeting the inclusion criteria were reviewed in full-text; 2 of these articles were eventually removed due to unconfirmed OSA diagnostic modality, and one was also removed based on a control group inconsistent with the other studies. Therefore, a total of 9 studies were included (n=19,837). Sample sizes ranged from n=160 patients to n=6841 patients. The risk of AF was found to be higher among OSA/SDB versus control group (OR; 2.120, C.I: 1.845-2.436, Z; 10.598 p: <0.001). The heterogeneity observed for the pooled analysis was Q-value; 22.487 df (Q); 8 P-value; 0.004, I-squared; 64.424 Tau2; 0.098, suggesting appropriate study selection and moderate heterogeneity. CONCLUSION: OSA/SDB is strongly associated with AFib confirming the notion that OSA/SDB populations are high risk for development of AF. Prospective studies are needed to ascertain the effect of the treatment of OSA/SDB for the prevention of AF, a growing health burden with serious consequences.

Monocyte-Derived Dendritic Cells Upregulate Extracellular Catabolism of Aggregated Low-Density Lipoprotein on Maturation, Leading to Foam Cell Formation.

OBJECTIVE: Although dendritic cells are known to play a role in atherosclerosis, few studies have examined the contribution of the wide variety of dendritic cell subsets. Accordingly, their roles in atherogenesis remain largely unknown. We investigated the ability of different dendritic cell subsets to become foam cells after contact with aggregated low-density lipoprotein (LDL; the predominant form of LDL found in atherosclerotic plaques). APPROACH AND RESULTS: We demonstrate that both murine and human monocyte-derived dendritic cells use exophagy to degrade aggregated LDL, leading to foam cell formation, whereas monocyte-independent dendritic cells are unable to clear LDL aggregates by this mechanism. Exophagy is a catabolic process in which objects that cannot be internalized by phagocytosis (because of their size or association with extracellular structures) are initially digested in an extracellular acidic lytic compartment. Surprisingly, we found that monocyte-derived dendritic cells upregulate exophagy on maturation. This contrasts various forms of endocytic internalization in dendritic cells, which decrease on maturation. Finally, we show that our in vitro results are consistent with dendritic cell lipid accumulation in plaques of an ApoE(-/-) mouse model of atherosclerosis. CONCLUSIONS: Our results show that monocyte-derived dendritic cells use exophagy to degrade aggregated LDL and become foam cells, whereas monocyte-independent dendritic cells are unable to clear LDL deposits. Furthermore, we find that exophagy is upregulated on dendritic cell maturation. Thus, exophagy-mediated foam cell formation in monocyte-derived dendritic cells could play a significant role in atherogenesis.

Occult Congenital Ureteropelvic Junction Obstruction in Two Adults Presenting with Collecting System Rupture After Blunt Renal Trauma: A Case Report Series.

We report two adult cases of congenital ureteropelvic junction obstruction detected incidentally in the setting of blunt abdominal trauma. CT images are provided to describe the presentation, while review of the literature and management of renal trauma are discussed.