Luke P. Brewster

Carotid revascularization outcomes comparing distal filters, flow reversal, and endarterectomy

INTRODUCTIONnContradictory outcomes exist for different methods of carotid artery revascularization. Here we provide the comparative rates of adverse events in patients after carotid endarterectomy (CEA), carotid artery stenting (CAS) with a distal embolic protection device (EPD), and CAS with a proximal flow reversal system (FRS) from a single institution by various specialists treating carotid artery disease.nnnMETHODSnProcedural billing codes and the electronic medical records of patients undergoing revascularization for carotid artery stenosis from February 2007 through March 2010 were used for data collection. Primary outcome was the incidence of cerebrovascular accident (CVA), myocardial infarction (MI), or death after CEA and CAS. Each practitioner determined the choice of therapy, with five of the 14 specialists providing both CAS and CEA. Baseline characteristics were examined for effect on outcome. Planned comparisons between and within groups were analyzed using χ(2), t tests, and analysis of variance, as appropriate.nnnRESULTSnA total of 495 procedures were documented, comprising 226 CEA, 216 CAS with EPD, and 53 CAS with FRS. Preoperative comparisons of patient comorbidities were similar among the cohorts. The carotid artery stenosis was symptomatic in 42% of these patients. Prior CEA was an indication for CAS rather than another CEA (P < .001). Significantly fewer patients undergoing CEA were receiving preoperative antiplatelet therapy (P < .001). The groups did not differ significantly in the overall composite end point of death, CVA, and MI (4%, 5.1%, 0%; P = .1) or any individual major adverse event. Overall, patients undergoing CAS with EPD had a statistically significant greater incidence of minor CVAs than CEA patients (P = .031), which was driven by the increased CVA risk for asymptomatic patients. Secondary end points occurred rarely (<2%). There have been no reoperations or interventions in these patients to date within this institution.nnnCONCLUSIONSnWe have established a similar and low incidence of MI, CVA, and death among patients undergoing CEA and CAS, of whom approximately 40% were symptomatic. FRS provided superior results in this series; however, its use was limited to 20% of the CAS procedures. Still, zero adverse events in this cohort make FRS an exciting technology that warrants a large-scale prospective comparative study.

Educational intervention is effective in improving knowledge and confidence in surgical ethics-a prospective study.

BACKGROUNDnProfessionalism and ethics are Accreditation Council for Graduate Medical Education (ACGME) core competencies, but there is little evidence regarding the effectiveness of ethics education.nnnMETHODSnGeneral surgery residents at the University of Pittsburgh completed questionnaires measuring attitudes and knowledge about surgical ethics before and after four 60-minute, faculty-facilitated seminars implementing the American College of Surgeons ethics curriculum.nnnRESULTSnMost residents experienced ethical challenges at least once every rotation: competition of interests (75%), professional obligations (75%), confidentiality (83%), truth telling (88%), surrogate decision making (91%), and end-of-life issues (100%). The educational intervention increased both knowledge about surgical ethics (P = .013) and confidence in dealing with competition of interests (P = .001), professional obligations (P = .011), truth telling (P = .013), confidentiality (P = .011), end-of-life issues (P = .007), and surrogate decision making (P = .052). Most residents recommended the American College of Surgeons text for future use (84%), considering ethics education a standard part of residency training (70%).nnnCONCLUSIONSnFocused instruction using the American College of Surgeons ethics curriculum can effectively improve both knowledge and confidence about surgical ethics.

Contralateral occlusion is not a clinically important reason for choosing carotid artery stenting for patients with significant carotid artery stenosis

OBJECTIVEnContralateral carotid artery occlusion by itself carries an increased risk of stroke. Carotid endarterectomy (CEA) in the presence of contralateral carotid artery occlusion has high reported rates of perioperative morbidity and mortality. Our objective was to determine if there is a clinical benefit to patients who receive carotid artery stenting (CAS) compared to CEA in the presence of contralateral carotid artery occlusion.nnnMETHODSnWe conducted a retrospective medical chart review over a 4.5-year institutional experience of persons with contralateral carotid artery occlusion and ipsilateral carotid artery stenosis who underwent CAS or CEA. The main outcome measures were 30-day cardiac, stroke, and mortality rate, and midterm mortality.nnnRESULTSnOf a total of 713 patients treated for carotid artery stenosis during this time period, 57 had contralateral occlusion (~8%). Thirty-nine of these patients were treated with CAS, and 18 with CEA. The most common indications for CAS were prior neck surgery (18), contralateral internal carotid occlusion (nine), and prior neck radiation (seven). The average age was 70 ± 8.5 for CEA and 66.7 ± 9.3 for CAS (P = .20). Both groups were predominantly men (CEA 12 of 18; CAS 28 of 39; P = .76), with similar prevalence of symptomatic lesions (CEA 8 of 18, CAS 20 of 39; P = .77). Two patients died within 30 days in the CAS group (5%). No deaths occurred within 30 days in the CEA group (P = .50); the mortality rate for CAS and CEA combined was 3.5%. No perioperative strokes or myocardial infarction occurred in either group. Two transient ischemic attacks occurred after CAS. At mean follow-up of 29.4 ± 16 months (CEA) and 28 ± 14.4 months (CAS; range, 1.5-48.5 months), seven deaths occurred in the CAS group and one in the CEA group (17.9% vs 5.5%; P = .40). There were two reinterventions in the CAS group for in-stent restenosis and there were no reoperations in the CEA group.nnnCONCLUSIONSnAlthough CEA and CAS can both be performed with good perioperative results and acceptable midterm mortality, the observed outcomes do not support use of contralateral carotid artery occlusion as a selection criterion for CAS over CEA in the absence of other indications.

Assessing Residents in Surgical Ethics: We Do It a Lot; We Only Know a Little

BACKGROUNDnPGY-1 year of surgical residency brings together many persons of disparate experiences and educational backgrounds, including their exposure to ethics. We hypothesized that surgical PGY-1s would have a similar exposure to ethical scenarios but lack the confidence in practice and understanding of ethical principles compared with more senior residents.nnnMATERIALS AND METHODSnSurgical residents were invited to resident-initiated surgical ethics workshops utilizing a standardized text. Here a survey and multiple choice tests were administered to participants. The survey determined prior exposure to ethics curricula, the frequency of exposure to various ethics topics, and their comfort with these scenarios. A multiple choice test then quantified the knowledge base of participating residents. The results were collected and compared between surgical PGY-1s and more senior residents.nnnRESULTSnEighteen PGY-1s and 12 senior residents completed this curriculum. Resident exposure to ethical concepts was common. Resident confidence in these topics was ranked moderate or higher for both groups. Despite frequent clinical exposure and strong confidence in their skills of addressing these topics, performance on the test was poor, with an average score of 59% for PGY-1s and 47% for more senior residents (P=0.03).nnnCONCLUSIONSnDespite clinical exposure to and confidence in their management of ethical topics, their knowledge base was poor and worse for more senior residents. Given the overall interest in a formal ethics curriculum and the knowledge deficit demonstrated, educational intervention and professional ethics support should be provided for surgical residents even with the current educational time constraints.

Regeneration: Letting the Scaffold do the Work

Barakat et al., in a paper recently published in the Journal of Surgical Research, report on the development of a humanized liver segment from a decellularized porcine liver by seeding the ‘‘liver’’ with human fetal hepatocytes and stellate cells [1] The authors demonstrate the ability to remove the cellular contents from the porcine liver and employ a fixation agent to cross-link collagen fibers for scaffold support. The cells were seeded into the scaffold via a perfusion apparatus, and this ‘‘liver’’ segment then demonstrated synthetic function ex vivo and tolerated implantation for 2 h in vivo. Given the need for organs continues to outpace supply, the authors’ work, if replicated on a lobe scale, could be utilized both as a temporary bridge or permanent liver for transplantation. Acellular grafts are thought to have the potential to address the in vitro issues of maintaining hepatocyte function for prolonged periods, supporting mature hepatocyte differentiation, and recapitulating hepatocyte proliferative capacity by facilitating key cell-cell and cell-ECM interactions found in vivo. The liver has a complicated anatomy and segregated physiology with arterial and venous perfusion and immune, synthetic, and excretory function. Its regenerative capacity has been of enormous interest, but this capacity is largely driven by hypertrophy of existing hepatocytes rather than regenerative mechanisms. Thus, this approach is not in kind to the clinical liver growth after hepatectomy but rather regenerative in nature. Theoretical concerns with the current approach will be answered by future work as this is pilot data. One potential avenue of coordinating hepatocytes with the biliary drainage system would be the use of oval progenitor cells, which have the capacity to differentiate into hepatocytes and cholangiocytes [2]. In order to perfuse an organ, adequate vascular flow must exist, and the perfusion of tissue engineered grafts has been a persistent problem for human-sized tissue. By maintaining vascular integrity with an intact basement membrane while decellularizing the vascular cells themselves, this work is of significant interest to the field of regenerative medicine and suggests that perfusion will not be the limiting step with this approach. Further support of this finding has been established in the less dense rodent liver [3]. Importantly, alternative perfusion strategies such as the layered cell sheet approach with inosculation of the vasculature between layers as described by Shimizu et al. [4] is not likely to help in a scaffold approach to organ regeneration. In a similarly challenging organ system for regenerative applications, Peterson et al. regenerated lung tissue and demonstrated excellent initial

Thoracic endovascular aneurysm repair for thoracic aneurysms: what we know, what to expect.

Descending thoracic aneurysms are less common and less likely to rupture than abdominal aortic aneurysms. However, when left untreated they are lethal, and repairs are recommended only if the size of the aneurysm is 6 cm, or smaller if symptomatic. Open thoracic aneurysm repair was the standard therapy the last time this topic was reviewed in Annals of Vascular Surgery. Currently, thoracic aneurysms are usually treated with endovascular means when anatomically appropriate. This review demonstrates the benefits of endografting (namely decreased perioperative mortality and morbidity) and also the shortcomings (no late mortality benefit) as currently published in the literature, as well as summarizing available endografts and specific considerations for high-risk patient populations.

Human diabetic mesenchymal stem cells from peripheral arterial disease patients promote angiogenesis through unique secretome signatures

Background. Diabetic patients are at increased risk of complications from severe peripheral arterial disease. Mesenchymal stem cells (MSC) may be useful in limiting these complications. Our objective is to test the angiogenic potential of diabetic versus healthy MSCs. Methods. MSCs angiogenic potential was tested by endothelial cell (EC) proliferation, migration, and 3‐dimensional sprouting. Diabetic conditions were simulated with 5.5, 20, or 40 mM glucose. MSC secretome was quantified by enzyme‐linked immunosorbent assay. Results. Human aortic ECs were most sensitive to glucose conditions and were used for all MSC experiments. Diabetic MSCs had greater 3‐dimensional invasion than healthy MSCs (P < .05), but EC sprouting was decreased in high glucose conditions in both diabetic and healthy MSCs. Secretome analysis demonstrated that 20mM glucose stimulated epidermal growth factor (EGF) expression in diabetic and healthy MSCs, but that diabetic MSCs had a unique secretome with increased levels of chemokine (C‐X‐C motif) ligand 1 (CXCL‐1), interleukin six (IL‐6), and monocyte chemoattractant protein 1 (MCP‐1) (P < .05). Conclusion. Despite having similar in vitro angiogenic activity, diabetic MSCs secrete a unique and inflammatory angiogenic signature that may influence MSC survival and function after transplantation in cell therapy applications. Strategies that normalize secretome in diabetic patients may improve the utility of autologous MSCs in this population of patients.

Limitations on Surrogate Decision-Making for Emergent Liver Transplantation

BACKGROUNDnSurrogate consent is an accepted form of promoting patient autonomy when patients cannot consent, but it can lead to surrogate duress and may be unreliable. Since consent for liver transplantation in patients with fulminant hepatic failure (FHF) is typically performed by surrogates and these patients typically regain decisional capacity, we chose this population to query patients opinion on the surrogate consent process.nnnMATERIALS AND METHODSnWe developed a questionnaire that queried transplanted patients experience and opinion on surrogate consent, suitability of surrogates, and return of decisional capacity. This survey was then sent to consecutive survivors of liver transplantation for FHF at our institution.nnnRESULTSnEleven of 14 patients eligible to participate completed the questionnaire. The mean follow-up for all survivors was 41 mo, with a range of survival since transplant of 5 mo to 10 y. Although 10/11 respondents agreed with their surrogates to consent to liver transplantation, all 11 patients thought that surrogates should not be able to decline liver transplantation for this condition. In distinction, 3/11 patients believed patients could decline liver transplantation.nnnCONCLUSIONSnThis is the first study to demonstrate that liver transplant patients do not think surrogate decision-makers should be permitted to contravene physician recommendations regarding transplant. In clinical settings when patients cannot speak for themselves, it may be appropriate for surrogates and clinicians to act together according to the patients best interest rather than attempt to determine what the patient would want. This approach might reduce surrogate distress, better represent patient preferences, and improve the decision-making process for affected patients.

Influence of the Hostile Neck on Restenosis after Carotid Stenting

BACKGROUNDnCarotid artery stenting (CAS) for carotid stenosis is favored over carotid endarterectomy (CEA) in patients with a hostile neck from prior CEA or cervical irradiation (XRT). However, the restenosis rate after CAS in patients with hostile necks is variable in the literature. The objective of this study was to quantify differences in the in-stent restenosis (ISR)/occlusion and reintervention rates after CAS in patients with and without a hostile neck. Here we hypothesize that patients with hostile necks have an increased ISR, and that this increase may add morbidity to these patients.nnnMATERIALS AND METHODSnAll patients undergoing CAS from 2007 to 2013 for carotid artery stenosis with follow-up imaging at our institution were queried from our carotid database (n = 236). Patients with hostile necks, including both CAS after prior CEA (n = 65) and prior XRT (n = 37), were compared with patients who underwent CAS for other reasons including both anatomical (n = 46) and medical comorbidities (n = 88). The primary end points were ISR, repeat intervention, and stent occlusion. Secondary end points of the study were stroke/myocardial infarction (MI)/death at 30 days, perioperative cardiovascular accident, transient ischemic attack, MI, groin access complications, hyperperfusion syndrome, and periprocedural hypotension or bradycardia.nnnRESULTSnDespite the hostile neck cohort being younger and having lower incidence of chronic obstructive pulmonary disease, coronary artery disease, and renal insufficiency, they had a greater incidence of ISR (11% vs. 4%; P = .03) and required more reinterventions (8% vs. 2%; P = .04). Stent occlusion and periprocedural morbidity/mortality were not different between groups.nnnCONCLUSIONSnPatients with hostile necks have increased risk of restenosis and need for reinterventions after CAS compared with patients without a hostile neck. However, they do not appear to have higher rates of stent occlusion or per-procedural events.

Femoral and carotid intima media thickness–two different measurements in two different arteries

* Corresponding author. Department of Surg 988 8768; fax: þ1 404 270 9167. E-mail address: lukebrewst@aol.com (L.P 0022-4804/