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Sabin J. Bozso Jeevan Nagendran Roderick G.G. MacArthur Michael W.A. Chu Bob Kiaii Ismail El-Hamamsy Raymond Cartier Ali Shahriari Michael C. Moon 《The Journal of thoracic and cardiovascular surgery》2019,157(5):1763-1771
Objectives
We describe the Canadian results of the Ascyrus Medical Dissection Stent (AMDS), a novel partially uncovered aortic arch hybrid graft implanted antegrade during hypothermic circulatory arrest to promote true lumen expansion and enhance aortic remodeling.Methods
From March 2017 to February 2018, 16 consecutive patients (66 ± 12 years; 38% female) presented with acute type A aortic dissections and underwent emergent surgical aortic repair with AMDS implantation. All patients presented with DeBakey I aortic dissection, with evidence of malperfusion in 50% (n = 8) of patients. All cases were performed under hypothermic circulatory arrest with an additional average duration for AMDS implantation time of 2.1 minutes.Results
All 16 device implantations were successful. Overall 30-day mortality was 6.3% (n = 1) and stroke occurred in 6.3% (n = 1) of cases. There was no incidence of device-related aortic injury or aortic arch branch vessel occlusion. During the follow-up period, 12 patients had completed at least 1 postoperative computed tomography scan. At initial follow-up computed tomography scan, complete or partial thrombosis, and remodeling of the aortic arch occurred in 91.7% of cases (n = 11/12) and in the proximal descending thoracic aorta, complete or partial thrombosis, and remodeling occurred in 91.7% (n = 11/12).Conclusions
Preliminary results suggest that the AMDS is a safe, feasible and reproducible adjunct to current surgical approaches for acute DeBakey I aortic dissection repair. Further, the AMDS manages malperfusion and promotes early positive remodeling in the aortic arch and distal dissected segments, with favorable FL closure rates at follow-up. Ongoing follow-up will provide additional insight into the long-term effects of the AMDS. 相似文献44.
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Valerio Zerbi Diane Jansen Pieter J. Dederen Andor Veltien Bob Hamans Yang Liu Arend Heerschap Amanda J. Kiliaan 《Brain structure & function》2013,218(5):1085-1098
Vascular disorders can either be cause or consequence in the pathophysiology of Alzheimer’s disease (AD). To comprehensively characterize the occurrence of vascular impairment in a double transgenic mouse model for AD (APPswe/PS1dE9) during aging, we developed a new method to obtain microvascular relative cerebral blood volume (rCBVmicro) maps from gradient echo MR imaging by histogram evaluation and we applied a voxel-wise approach to detect rCBVmicro changes. With this methodology the development of cerebral microvascular impairments can be described in vivo with 0.16 mm isotropic resolution for the whole mouse brain. At 8 months, impaired rCBVmicro appeared in some cortical regions and in the thalamus, which spreads over several sub-cortical areas and the hippocampus at 13 months. With a ROI-based approach, we further showed that hippocampal rCBVmicro in 13-month-old wild-type and APPswe/PS1dE9 mice correlates well with capillary density measured with immunohistochemical staining. However, no differences in capillary density were detected between genotypes. The rCBVmicro values showed no significant correlation with amyloid-β (Aβ) plaque deposition, Aβ at blood vessel walls and biochemically measured levels of Aβ1-40, Aβ1-42 oligomers and fibrillar forms. These results suggest that rCBVmicro reduction is caused by an impaired vasoactivity of capillaries and arterioles, which is not directly correlated with the amount of Aβ deposition in parenchyma nor blood vessel walls. 相似文献
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Although most skin lesions in neonates are transient or benign, they may also be the presenting symptom of a life-threatening disease such as herpes neonatorum. In the present review, we present a short overview of neonatal skin lesions and a practical table to guide the general paediatrician in the diagnosis and management of neonatal skin lesions. Recent reviews are cited for further reading. 相似文献
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Ronald A. Dieckmann Jean Athey Bob Bailey Jeff Michael 《Prehospital emergency care》2013,17(3):231-236
Emergency medical services for children, or EMSC, is still a relatively underdeveloped component of most state and local EMS systems. Advocacy and funding for EMSC from the federal EMSC Program, availability of many useful EMSC products, and the rapidly enlarging literature in EMSC have created heightened awareness and interest in improving systems for pediatric emergency, trauma, and critical care. The new National Highway Traffic Safety Administration (NHTSA) EMS Technical Assistance (TA) re-assessment program, the second version of the successful original TA Program from 1988 to 1996, provides an ideal opportunity for state EMS professionals to evaluate EMSC capabilities and to integrate new EMSC products and services. The history of the TA Program reflects the evolution of EMS itself and indicates a historical inattention to children's issues, but re-assessment TA teams now have much useful intervening EMSC history to draw upon and a clear philosophical mandate to integrate children more fully in EMS system planning and management. In order to facilitate state-of-the-art reviews of EMSC within state EMS systems, a pediatric survey for the NHTSA re-assessments is presented. The survey, developed with the input of EMS administrators and physicians and approved by the National Association of State EMS Directors, follows the original ten-component model for EMS system review. It is intended for optional use within the overall EMS review process. 相似文献