Endovascular repair of thoracic aortic pseudoaneurysms and patch aneurysms

Pseudoaneurysms and patch aneurysms are life-threatening late complications after thoracoabdominal aortic aneurysm (TAAA) repair. We treated four patients who presented with a pseudoaneurysm or patch aneurysm involving the descending thoracic portion of a previously implanted TAAA graft. In each patient, stent grafts were placed within the existing graft to cover the aneurysm endoluminally. All patients recovered without major complications, and computed tomography performed after a mean follow-up of 51.5 ± 19.7 months showed that the repairs remained intact

Outcomes of concomitant aortic valve replacement and coronary artery bypass grafting at teaching hospitals versus nonteaching hospitals

ObjectiveHospitals with a high volume and academic status produce better patient outcomes than other hospitals after complex surgical procedures. Risk models show that concomitant aortic valve replacement and coronary artery bypass grafting pose a greater risk than isolated coronary artery bypass grafting or aortic valve replacement. We examined the relationship of hospital teaching status and the presence of a thoracic surgery residency program with aortic valve replacement/coronary artery bypass grafting outcomes.MethodsBy using the Nationwide Inpatient Sample database, we identified patients who underwent concomitant aortic valve replacement/coronary artery bypass grafting from 1998 to 2007 at nonteaching hospitals, teaching hospitals without a thoracic surgery residency program, and teaching hospitals with a thoracic surgery residency program. Multivariate analysis was performed to identify intergroup differences. Risk-adjusted multivariable logistic regression analysis was used to assess independent predictors of in-hospital mortality and complication rates.ResultsThe 3 groups of patients did not differ significantly in their baseline characteristics. Patients who underwent aortic valve replacement/coronary artery bypass grafting had higher overall risk-adjusted complication rates in nonteaching hospitals (odds ratio 1.58; 95% confidence interval, 1.39–1.80; P < .0001) and teaching hospitals without a thoracic surgery residency program (odds ratio 1.42; 95% confidence interval, 1.26–1.60; P < .0001) than in thoracic surgery residency program hospitals. However, no difference was observed in the adjusted mortality rate for nonteaching hospitals (odds ratio 0.95; 95% confidence interval, 0.87–1.04; P = .25) or teaching hospitals without a thoracic surgery residency program (odds ratio 1.00; 95% confidence interval, 0.92–1.08; P = .98) when compared with thoracic surgery residency program hospitals. Robust statistical models were used for analysis, with c-statistics of 0.98 (complications) and 0.82 (mortality).ConclusionPatients who require complex cardiac operations may have better outcomes when treated at teaching hospitals with a thoracic surgery residency program

HCMV infection attenuates hydrogen peroxide induced endothelial apoptosis – involvement of ERK pathway

AbstractHuman cytomegalovirus (HCMV) exerts anti-apoptotic effect during early stage of infection, which provides HCMV time for propagation. We investigated pathways mediating the resistance to H2O2-induced cell death – a self-defense mechanism to remove infected cells. We found that human aortic endothelial cells (HAECs) infected with VHL/E strain of HCMV during first 3 days were resistant to H2O2 (0–2mM) induced apoptosis. This anti-apoptotic effect may be mediated by the upregulation of Bcl-2, an anti-apoptotic protein through the activation pro-survival pathway extracellular signal regulated kinase (ERK). Through this mechanism, HCMV is able to propagate and causes endothelial dysfunction, hence vascular disease

Endovascular versus open repair of ruptured descending thoracic aortic aneurysms: A nationwide risk-adjusted study of 923 patients

ObjectiveRecent studies support the use of endovascular treatment for ruptured abdominal aortic aneurysms, but few studies have examined the use of thoracic endovascular aortic repair (TEVAR) for ruptured descending thoracic aortic aneurysm. We evaluated nationwide data regarding short-term outcomes of TEVAR and open aortic repair (OAR) for ruptured descending thoracic aortic aneurysm.MethodsFrom US Nationwide Inpatient Sample data, we identified 923 patients who underwent ruptured descending thoracic aortic aneurysm repair in 2006–2008 and who had no concomitant aortic disorders. Of these patients, 364 (39.4%) underwent TEVAR and 559 (60.6%) underwent OAR. Multivariable regression was used to assess the effect of TEVAR versus OAR after adjusting for potential confounding factors. Outcomes assessed were in-hospital mortality, complications, failure to rescue (defined as the mortality among patients in whom a complication develops), and disposition. Backward stepwise logistic regression was used to identify independent predictors of outcomes for each approach.ResultsPatients undergoing TEVAR were older (72 ± 12 years vs 65 ± 15 years; P < .001) and had a higher Deyo comorbidity index (4.19 ± 1.79 vs 3.14 ± 2.05; P < .001) than patients undergoing OAR. Unadjusted mortality was 23.4% (85/364) for TEVAR and 28.6% (160/559) for OAR. After risk adjustment, the odds of mortality, complications, and failure to rescue were similar for TEVAR and OAR (P > .1 for all), but patients undergoing TEVAR had a greater chance of routine discharge (odds ratio [OR] = 3.3; P < .001). An interaction was identified that linked hospital size and operative approach with risk of complications (P < .001). In smaller hospitals, TEVAR was associated with lower complication rates than OAR (OR = 0.21; P < .05). Regression analysis revealed that smaller hospital size predicted significantly higher rates of mortality (OR = 2.4; P < .05), complications (OR = 4.0; P < .005), and failure to rescue (OR = 51.12; P < .001) in those undergoing OAR but not in those undergoing TEVAR. Preexisting renal disorders substantially increased mortality risk (OR = 10.81; P < .001) and failure to rescue (OR = 309.54; P < .001) in patients undergoing TEVAR.ConclusionsNationwide data for ruptured descending thoracic aortic aneurysm reveal equivalent mortality, complication rates, and failure to rescue for TEVAR and OAR but more frequent routine discharge with TEVAR. Unlike OAR outcomes, TEVAR outcomes were not poorer in smaller hospitals, where TEVAR produced fewer complications than OAR. Therefore, TEVAR may be an ideal alternative to OAR for ruptured descending thoracic aortic aneurysm, particularly in small hospitals where expertise in OAR may be lacking and immediate transfer to a higher echelon of care may not be feasible

Modeling of biological doses and mechanical effects on bone transduction

Shear stress, hormones like parathyroid and mineral elements like calcium mediate the amplitude of stimulus signal which affects the rate of bone remodeling. The current study investigates the theoretical effects of different metabolic doses in stimulus signal level on bone. The model was built considering the osteocyte as the sensing center mediated by coupled mechanical shear stress and some biological factors. The proposed enhanced model was developed based on previously published works dealing with different aspects of bone transduction. It describes the effects of physiological doses variations of Calcium, Parathyroid Hormone, Nitric Oxide and Prostaglandin E2 on the stimulus level sensed by osteocytes in response to applied shear stress generated by interstitial fluid flow. We retained the metabolic factors (Parathyroid Hormone, Nitric Oxide, and Prostaglandin E2) as parameters of bone cell mechanosensitivity because stimulation/inhibition of induced pathways stimulates osteogenic response in vivo. We then tested the model response in term of stimulus signal variation versus the biological factors doses to external mechanical stimuli. Despite the limitations of the model, it is consistent and has physiological bases. Biological inputs are histologically measurable. This makes the model amenable to experimental verification

Valve-sparing and valve-replacing techniques for aortic root replacement in patients with Marfan syndrome: Analysis of early outcome

ObjectiveA prospective, international registry study was initiated to provide contemporary comparative data on short-term clinical outcomes after aortic valve-sparing and aortic valve-replacing root operations in patients with Marfan syndrome. The purpose of this initial report is to describe the study design and to compare early outcomes in the first 151 enrolled patients.MethodsWe assessed 30-day outcomes in 151 patients who met strict Ghent diagnostic criteria for Marfan syndrome and underwent aortic root replacement with either valve-replacing (n = 46) or valve-sparing techniques (n = 105) at one of 18 participating centers. In the valve replacement group, a mechanical composite valve graft was used in 39 (85%) patients and a bioprosthetic valve in 7 (15%). In the valve-sparing group, David V procedures were performed in 57 (54%) patients, David I in 38 (36%), David IV in 8 (8%), Florida sleeve in 1 (1%), and Yacoub remodeling in 1 (1%).ResultsNo in-hospital or 30-day deaths occurred. Despite longer crossclamp and cardiopulmonary bypass times in the valve-sparing group, there were no significant between-group differences in postoperative complications. Thirty-day valve-related complications occurred in 2 (4%) patients undergoing valve replacement and in 3 (3%) undergoing valve-sparing procedures (P = .6).ConclusionsThe analysis of early outcomes revealed that valve-sparing techniques were the most common approach to root replacement in patients with Marfan syndrome in these centers. The complexity of valve-sparing root replacement did not translate into any demonstrable adverse early outcomes. Subsequent analysis will compare the 3-year durability of these two surgical approaches

Rational design and characterization of bioplastics from Hermetia illucens prepupae proteins

In this study proteins extracted from prepupae of Hermetia illucens, also known as black soldier fly,are investigated as promising base for a new type of bioplastics for agricultural purposes. Designof experiments techniques are employed to perform a rational study on the effects of differentcombination of glycerol as plasticizer, citric acid as cross-linking agent and distilled water as solventon the capability of proteins to form a free-standing film through casting technique, keeping asfixed the quantity of proteins. Glycerol shows interesting properties as plasticizer contributing tothe formation of homogenous and free-standing film. Moreover, mechanical and thermalcharacterizations are performed to estimate the effect of increasing amounts of proteins on thefinal properties and thickness of the specimens. Proteins derived from H. illucens can be success-fully employed as base for bioplastics to be employed for agricultural purposes

Emotion and coping in the aftermath of medical error: A cross country exploration.

Objectives: Making a medical error can have serious implications for clinician wellbeing, affecting the quality and safety of patient care. Despite an advancing literature base, cross-country exploration of this experience is limited and a paucity of studies has examined the coping strategies used by clinicians. A greater understanding of clinicians¿ responses to making an error, the factors that may influence these, and the various coping strategies used are all essential for providing effective clinician support and ensuring optimal outcomes. The objectives were therefore to investigate a) the professional or personal disruption experienced after making an error, b) the emotional response and coping strategies used, c) the relationship between emotions and coping strategy selection, d) influential factors in clinicians¿ responses, and e) perceptions of organisational support. Methods: A cross-sectional, cross-country survey of 265 physicians and nurses was undertaken in two large teaching hospitals in the UK and USA. Results: Professional and personal disruption was reported as a result of making an error. Negative emotions were common, but positive feelings of determination, attentiveness and alertness were also identified. Emotional response and coping strategy selection did not differ due to location or perceived harm, but responses did appear to differ by professional group; nurses in both locations reported stronger negative feelings after an error. Respondents favoured problem-focused coping strategies and associations were identified between coping strategy selection and the presence of particular emotions. Organisational support services, particularly including peers, were recognised as helpful, but fears over confidentiality may prohibit some staff from accessing these. Conclusions: Clinicians in the UK and US experience professional and personal disruption after an error. A number of factors may influence clinician recovery; these factors should be considered in the provision of comprehensive support programmes so as to improve clinician recovery and ensure higher quality, safer patient care.British Psychological Society Travel Gran

Aortic Complications Associated With Pregnancy in Marfan Syndrome: The NHLBI National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC)

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139073/1/jah31693.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139073/2/jah31693_am.pd

Single-Cell Analysis of Aneurysmal Aortic Tissue in Patients with Marfan Syndrome Reveals Dysfunctional TGF-β Signaling

The molecular and cellular processes leading to aortic aneurysm development in Marfan syndrome (MFS) remain poorly understood. In this study, we examined the changes of aortic cell populations and gene expression in MFS by performing single-cell RNA sequencing (scRNA seq) on ascending aortic aneurysm tissues from patients with MFS (n = 3) and age-matched non-aneurysmal control tissues from cardiac donors and recipients (n = 4). The expression of key molecules was confirmed by immunostaining. We detected diverse populations of smooth muscle cells (SMCs), fibroblasts, and endothelial cells (ECs) in the aortic wall. Aortic tissues from MFS showed alterations of cell populations with increased de-differentiated proliferative SMCs compared to controls. Furthermore, there was a downregulation of MYOCD and MYH11 in SMCs, and an upregulation of COL1A1/2 in fibroblasts in MFS samples compared to controls. We also examined TGF-β signaling, an important pathway in aortic homeostasis. We found that TGFB1 was significantly upregulated in two fibroblast clusters in MFS tissues. However, TGF-β receptor genes (predominantly TGFBR2) and SMAD genes were downregulated in SMCs, fibroblasts, and ECs in MFS, indicating impairment in TGF-β signaling. In conclusion, despite upregulation of TGFB1, the rest of the canonical TGF-β pathway and mature SMCs were consistently downregulated in MFS, indicating a potential compromise of TGF-β signaling and lack of stimulus for SMC differentiation