Technical and clinical success after endovascular therapy for chronic type B aortic dissections

ObjectiveTo analyze early technical success and late clinical success after endovascular entry sealing for chronic type B dissection with special emphasis on reintervention, false lumen thrombosis, and aortic remodeling.MethodsRetrospective analysis of a prospective database. From September 1999 to January 2011, 19 patients with chronic type B dissections were treated by endovascular entry sealing. Median age was 60 years. Median time between onset of acute dissection and surgical intervention was 36 (1 to 60) months. Median follow-up was 13 months (1 to 124).ResultsThe endografts used were: Medtronic Captivia (5), Medtronic Valiant (5), Gore TAG (6), Gore C-TAG (2), and Cook Zenith (1). In four patients, revascularization of the left subclavian artery was performed prior to entry sealing. Primary technical success rate (entry sealing, absence of type I leak) was 18/19 (94.7%). In-hospital mortality was 0%. Spinal cord injury with persistent paraplegia occurred in 1/19 (5.2%) patients. After a maximal follow-up of 124 months, reinterventions in 9/19 (47.3%) were necessary: distal/proximal extension of stent graft (8), replacement of the aortic arch due to retrograde dissection (1), and open infrarenal aneurysm repair (1). During follow-up, none of the patients died due to stent-related complications.ConclusionEndovascular treatment (EVT) in chronic type B dissections has a high technical success rate and low mortality/morbidity. However reintervention rates are not negligible which might reduce the clinical success of EVT. Future investigations should aim at identifying patients who benefit from EVT at better defining the timing of EVT and at determining if entry sealing alone is sufficient

Effect of statin therapy on serum activity of proteinases and cytokines in patients with abdominal aortic aneurysm

Bernd Muehling1, Alexander Oberhuber1, Hubert Schelzig1, Gisela Bischoff1, Nikolaus Marx2, Ludger Sunder-Plassmann1, Karl H Orend11Department of Thoracic and Vascular surgery; 2Department of Internal Medicine, University of Ulm, Ulm, GermanyBackground and aims: Metalloproteinases (MMPs) are considered to be key enzymes in the pathogenesis of abdominal aortic aneurysms (AAA), with elevated levels in diseased aorta and in patient sera. Statins seem to exert an inhibitory effect on MMP activity in the aortic wall. No data exist on the effect of statins on serum activity of MMPs and inflammatory cytokines (interleukins, IL).Methods: The serum activities of MMP2 and MMP9, osteoprotegerin (OPG), and IL6 and IL10 in 63 patients undergoing elective infrarenal aneurysm repair were measured on the day before surgery. Levels were correlated to statin therapy and aneurysm diameter.Results: There was no significant difference between the two groups in the activity of circulating levels of MMP2/9, OPG, and IL6/10 in patients with infrarenal aortic aneurysm. IL6 levels in patients with AAA larger than 6 cm were significantly elevated; differences in serum activities of MMP2/9, OPG, and IL10 were not related to AAA diameter.Conclusion: Serum activities of MMP2/9, OPG, and IL6/10 are not correlated to statin therapy; IL6 levels are higher in patients with large aneurysms. Hence the effect of statin therapy in the treatment of aneurismal disease remains to be elucidated.Keywords: biomarkers, aneurismal disease, statin therap

Neurotherapeutic potential of erythropoietin after ischemic injury of the central nervous system

Erythropoietin (EPO) is one of the most successful biopharmaceuticals in history and is used for treating anemia of different origins. However, it became clear that EPO could also work in a neuroprotective, antiapoptotic, antioxidative, angiogenetic and neurotropic way. It causes stimulation of cells to delay cell apoptosis, especially in the central nervous system. In rodent models of focal cerebral ischemia, EPO showed an impressive reduction of infarct size by 30% and improvement of neurobehavioral outcome by nearly 40%. A large animal model dealing with ischemia and reperfusion of the spinal cord showed that EPO could reduce the risk of spinal cord injury significantly. In addition, some clinical studies tested whether EPO works in real live clinical settings. One of the most promising studies showed the innocuousness and improvements in follow-up, outcome scales and in infarct size, of EPO-use in humans suffering from ischemic stroke. Another study ended unfortunately in a negative outcome and an increased overall death rate in the EPO group. The most possible reason was the involvement of patients undergoing simultaneously systemic thrombolysis with recombinant tissue plasminogen activator. An experimental study on rats demonstrated that administration of EPO might exacerbate tissue plasminogen activator-induced brain hemorrhage without reducing the ischemic brain damage. This case shows clearly how useful animal models can be to check negative side effects of a treatment before going into clinical trials. Other groups looked in human trials at the effects of EPO on the outcome after ischemic stroke, relation to circulating endothelial progenitor cells, aneurysmal subarachnoid hemorrhage, traumatic brain injury, hemoglobin transfusion thresholds and elective first-time coronary artery bypass surgery. Most of the results were positive, but are based mostly on small group sizes. However, some of the most neglected facts when focusing on experimental setups of ischemia of the central nervous system are issues like age and comorbidities. It might be extremely worthy to consider these points for future projects, because EPO might influence all these factors

Ready for the OR? – Clinical anatomy and basic surgical skills for students in their preclinical education

Medical students’ first experience in the operating theatre often takes place during their electives and is therefore separated from the university’s medical curriculum. In the winter term 2009/10, the Institute of Anatomy and Cell Biology at the University of Ulm implemented an elective called “Ready for the OR” for 2nd year medical students participating in the dissection course. We attempted to improve learning motivation and examination results by transferring anatomical knowledge into a surgical setting and teaching basic surgical skills in preparation of the students’ first participation in the OR. Out of 69 online applicants, 50 students were randomly assigned to the Intervention Group (FOP) or the Control Group. In 5 teaching session students learned skills like scrubbing, stitching or the identification of frequently used surgical instruments. Furthermore, students visited five surgical interventions which were demonstrated by surgical colleagues on donated bodies that have been embalmed using the Thiel technique. The teaching sessions took place in the institute’s newly built “Theatrum Anatomicum” for an ideal simulation of a surgical setting. The learning outcomes were verified by OSPE. In a pilot study, an intervention group and a control group were compared concerning their examination results in the dissection course and their learning motivation through standardized SELLMO-test for students. Participants gained OSPE results between 60.5 and 92% of the maximum score. “Ready for the OR” was successfully implemented and judged an excellent add-on to anatomy teaching by the participants. However, we could not prove a significant difference in learning motivation or examination results. Future studies should focus on the learning orientation, the course’s long-term learning effects and the participants’ behavior in a real surgery setting

Role of the CX3C chemokine receptor CX3CR1 in the pathogenesis of atherosclerosis after aortic transplantation

Background: The CX3C chemokine receptor CX3CR1 is expressed on monocytes as well as tissue resident cells, such as smooth muscle cells ( SMCs). Its role in atherosclerotic tissue remodeling of the aorta after transplantation has not been investigated. Methods: We here have orthotopically transplanted infrarenal Cx3cr1(-/-) Apoe(-/-) and Cx3cr1(+/+) Apoe(-/-)aortic segments into Apoe(-/-) mice, as well as Apoe(-/-) aortic segments into Cx3cr1(-/-) Apoe(-/-)mice. The intimal plaque size and cellular plaque composition of the transplanted aortic segment were analyzed after four weeks of atherogenic diet. Results: Transplantation of Cx3cr(-/-) Apoe(-/-) aortic segments into Apoe(-/-) mice resulted in reduced atherosclerotic plaque formation compared to plaque size in Apoe(-/-) or Cx3cr1(-/-) Apoe(-/-) mice after transplantation of Apoe(-/-) aortas. This reduction in lesion formation was associated with reduced numbers of lesional SMCs but not macrophages within the transplanted Cx3cr(-/-) Apoe(-/-) aortic segment. No differences in frequencies of proliferating and apoptotic cells could be observed. Conclusion These results indicate that CX3CR1 on resident vessel wall cells plays a key role in atherosclerotic plaque formation in transplanted aortic grafts. Targeting of vascular CX3CL1/ CX3CR1 may therefore be explored as a therapeutic option in vascular transplantation procedures

Chronic Nicotine Exposure Induces Murine Aortic Remodeling and Stiffness Segmentation - Implications for Abdominal Aortic Aneurysm Susceptibility

Aim: Arterial stiffness is a significant risk factor for many cardiovascular diseases, including abdominal aortic aneurysms (AAA). Nicotine, the major active ingredient of e-cigarettes and tobacco smoke, induces acute vasomotor effects that may temporarily increase arterial stiffness. Here, we investigated the effects of long-term nicotine exposure on structural aortic stiffness. Methods: Mice (C57BL/6) were infused with nicotine for 40 days (20 mg/kg/day). Arterial stiffness of the thoracic (TS) and abdominal (AS) aortic segments was analyzed using ultrasound (PVVV, pulse wave velocity) and ex vivo pressure myograph measurements. For mechanistic studies, aortic matrix-metalloproteinase (MMP) expression and activity as well as medial elastin architecture were analyzed. Results: Global aortic stiffness increased with nicotine. In particular, local stiffening of the abdominal segment occurred after 10 days, while thoracic aortic stiffness was only increased after 40 days, resulting in aortic stiffness segmentation. Mechanistically, nicotine exposure enhanced expression of MMP-2/-9 and elastolytic activity in both aortic segments. Elastin degradation occurred in both segments;however, basal elastin levels were higher in the thoracic aorta. Finally, MMP-inhibition significantly reduced nicotine-induced MMP activity, elastin destruction, and aortic stiffening. Conclusion: Chronic nicotine exposure induces aortic MMP expression and structural aortic damage (elastin fragmentation), irreversibly increasing aortic stiffness. This process predominantly affects the abdominal aortic segment, presumably due in part to a lower basal elastin content. This novel phenomenon may help to explain the role of nicotine as a major risk factor for AM formation and has health implications for ECIGs and other modes of nicotine delivery

Chronic Nicotine Exposure Induces Murine Aortic Remodeling and Stiffness Segmentation—Implications for Abdominal Aortic Aneurysm Susceptibility

Aim: Arterial stiffness is a significant risk factor for many cardiovascular diseases, including abdominal aortic aneurysms (AAA). Nicotine, the major active ingredient of e-cigarettes and tobacco smoke, induces acute vasomotor effects that may temporarily increase arterial stiffness. Here, we investigated the effects of long-term nicotine exposure on structural aortic stiffness.Methods: Mice (C57BL/6) were infused with nicotine for 40 days (20 mg/kg/day). Arterial stiffness of the thoracic (TS) and abdominal (AS) aortic segments was analyzed using ultrasound (PWV, pulse wave velocity) and ex vivo pressure myograph measurements. For mechanistic studies, aortic matrix-metalloproteinase (MMP) expression and activity as well as medial elastin architecture were analyzed.Results: Global aortic stiffness increased with nicotine. In particular, local stiffening of the abdominal segment occurred after 10 days, while thoracic aortic stiffness was only increased after 40 days, resulting in aortic stiffness segmentation. Mechanistically, nicotine exposure enhanced expression of MMP-2/-9 and elastolytic activity in both aortic segments. Elastin degradation occurred in both segments; however, basal elastin levels were higher in the thoracic aorta. Finally, MMP-inhibition significantly reduced nicotine-induced MMP activity, elastin destruction, and aortic stiffening.Conclusion: Chronic nicotine exposure induces aortic MMP expression and structural aortic damage (elastin fragmentation), irreversibly increasing aortic stiffness. This process predominantly affects the abdominal aortic segment, presumably due in part to a lower basal elastin content. This novel phenomenon may help to explain the role of nicotine as a major risk factor for AAA formation and has health implications for ECIGs and other modes of nicotine delivery