Renal and visceral protection in thoracoabdominal aortic surgery

ObjectivesOpen thoracoabdominal aortic aneurysm (TAAA) repair traditionally carries substantial perioperative morbidity and mortality, primarily from distal aortic ischemia. Advances in surgical techniques, adjuncts, and strategies have greatly improved outcomes.MethodsWe analyzed outcomes of 1267 open consecutive TAAA repairs between January 2005 and September 2013. We provided cold crystalloid renal perfusion whenever the renal ostia were accessible; according to extent of repair, we selectively used left heart bypass and provided isothermic blood to the celiac axis and superior mesenteric artery. Repair was extensive (Crawford extent I and II) in 717 cases (57%). Left heart bypass was used in 645 (51%) cases, cold crystalloid renal perfusion in 987 (78%), and isothermic visceral perfusion in 318 (25%). Additional patient-specific surgical adjuncts included endarterectomy of renal or visceral vessels, open stent placement within these vessels, or use of both techniques; at least one was used in 447 repairs (35%).ResultsThirty-day survival was 95% (1198/1267); overall operative mortality was 8% (104/1267). Acute renal dysfunction occurred in 155 (12%), renal failure requiring hemodialysis at hospital discharge in 84 (7%), and bowel ischemia in 9 (<1%). Extent II and III TAAA repairs carried the highest risks of postoperative renal dysfunction and renal failure requiring hemodialysis at hospital discharge.ConclusionsContemporary protective strategies allow open TAAA repair with substantially fewer renal and visceral ischemic complications. Although bowel ischemia is uncommon, renal failure remains a concern, especially in extent II and extent III TAAA repairs. Additional studies are needed to identify and improve renal protection strategies

Successful repair of mega aorta using reversed elephant trunk procedure

AbstractThe case reported is of a patient with mega aorta and a symptomatic thoracoabdominal aortic segment. Successful treatment involved resection and graft replacement of the thoracoabdominal segment as an initial procedure using a “reversed elephant trunk” technique, followed by resection and replacement of the ascending aorta and transverse aortic arch as the second stage. (J Vasc Surg 1998;27:183-8.

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

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

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

Homograft use in reoperative aortic root and proximal aortic surgery for endocarditis: A 12-year experience in high-risk patients

ObjectivesWe examined the early and midterm outcomes of homograft use in reoperative aortic root and proximal aortic surgery for endocarditis and estimated the associated risk of postoperative reinfection.MethodsFrom January 2001 to January 2014, 355 consecutive patients underwent reoperation of the proximal thoracic aorta. Thirty-nine patients (10.9%; mean age, 55.4 ± 13.3 years) presented with active endocarditis; 30 (76.9%) had prosthetic aortic root infection with or without concomitant ascending and arch graft infection, and 9 (23.1%) had proximal ascending aortic graft infection with or without aortic valve involvement. Sixteen patients (41.0%) had genetically triggered thoracic aortic disease. Twelve patients (30.8%) had more than 1 prior sternotomy (mean, 2.4 ± 0.6).ResultsValved homografts were used to replace the aortic root in 29 patients (74.4%); nonvalved homografts were used to replace the ascending aorta in 10 patients (25.6%). Twenty-five patients (64.1%) required concomitant proximal arch replacement with a homograft, and 2 patients (5.1%) required a total arch homograft. Median cardiopulmonary bypass, cardiac ischemia, and circulatory arrest times were 186 (137-253) minutes, 113 (59-151) minutes, and 28 (16-81) minutes. Operative mortality was 10.3% (n = 4). The rate of permanent stroke was 2.6% (n = 1); 3 additional patients had transient neurologic events. One patient (1/35, 2.9%) returned with aortic valve stenosis 10 years after the homograft operation. During the follow-up period (median, 2.5 years; range, 1 month to 12.3 years), no reinfection was reported, and survival was 65.7%.ConclusionsThis is one of the largest North American single-center series of homograft use in reoperations on the proximal thoracic aorta to treat active endocarditis. In this high-risk population, homograft tissue can be used with acceptable early and midterm survival and a low risk of reinfection. When necessary, homograft tissue may be extended into the distal ascending and transverse aortic arch, with excellent results. These patients require long-term surveillance for both infection and implant durability

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

Subjective assessment underestimates surgical risk: On the potential benefits of cardiopulmonary exercise testing for open thoracoabdominal repair

BACKGROUND: Initial clinical evaluation (ICE) is traditionally considered a useful screening tool to identify frail patients during the preoperative assessment. However, emerging evidence supports the more objective assessment of cardiorespiratory fitness (CRF) via cardiopulmonary exercise testing (CPET) to improve surgical risk stratification. Herein, we compared both subjective and objective assessment approaches to highlight the interpretive idiosyncrasies. METHODS: As part of routine preoperative patient contact, patients scheduled for major surgery were prospectively “eyeballed” (ICE) by two experienced clinicians before more detailed history taking that also included the American Society of Anesthesiologists score classification. Each patient was subjectively judged to be either “frail” or “not frail” by ICE and “fit” or “unfit” from a thorough review of the medical notes. Subjective data were compared against the more objective validated assessment of postoperative outcomes using established CPET “cut‐off” metrics incorporating peak pulmonary oxygen uptake, V̇O(2PEAK) at the anaerobic threshold (V̇O(2)‐AT), and ventilatory equivalent for carbon dioxide that collectively informed risk stratification. These data were retrospectively extracted from a single‐center prospective National Health Service database. Data were analyzed using the Chi‐square automatic interaction detection decision tree method. RESULTS: A total of 127 patients were examined that comprised 58% male and 42% female patients aged 69 ± 10 years with a body mass index of 29 ± 7 kg/m(2). Patients were poorly conditioned with a V̇O(2PEAK) almost 20% lower than predicted for age, sex‐matched healthy controls with 35% exhibiting a V̇O(2)‐AT < 11 ml/kg/min. Disagreement existed between the subjective assessments of risk with ∼34% of patients classified as not frail on ICE were considered unfit by notes review (p < .0001). Furthermore, ∼35% of patients considered not frail on ICE and ∼31% of patients considered fit by notes review exhibited a V̇O(2)‐AT < 11 ml/kg/min, and of these, ∼28% and ∼19% were classified as intermediate to high risk. CONCLUSIONS: These findings highlight the interpretive limitations associated with the subjective assessment of patient frailty with surgical risk classification underestimated in up to a third of patients compared to the validated assessment of CRF. They reinforce the benefits of a more objective and integrated approach offered by CPET that may help us to improve perioperative risk assessment and better direct critical care provision in patients scheduled for “high‐stakes” surgery including open thoracoabdominal aortic aneurysm repair