W. Darrin Clouse

Durability of aortouniiliac endografting with femorofemoral crossover: 4-year experience in the evt/guidant trials

OBJECTIVES We evaluated mid-term results of the multicenter EVT/Guidant aortouniiliac endograft (AI) trial and ascertained the durability of this endovascular technique in patients unable to undergo standard bifurcated endografting. METHODS From November 1996 to December 1998, 121 patients were enrolled to receive the AI device on the basis of complex iliac artery anatomy contraindicating bifurcated endografting. Clinical data were centrally collected, and radiographic data were evaluated by core facility. RESULTS AI placement was technically successful in 113 of 121 patients. At operation, patients who underwent AI had significantly more arrhythmias, congestive heart failure, and peripheral occlusive disease (P <.05) compared with patients who underwent open aneurysmorrhaphy in the EVT/Guidant trials, indicating comorbid features in this anatomic cohort. Distal AI attachment was performed to the external iliac artery in 40 (36%) patients. Median follow-up was 38 months. In the AI group, overall aneurysm diameter decreased over the duration of study from 54.4 +/- 9.6 mm to 44.4 +/- 16.4 mm (P =.004). At 24 and 36 months after repair, reduction in aneurysm size was associated with absence of endoleak (P =.003 and P =.008, respectively). Aneurysms shrunk or remained stable in 109 (96.5%) patients. Endoleak was identified in 52.3% of patients at discharge, and at follow-up in 30.9% at 1 year, 34.8% at 2 years, 28.6% at 3 years, and 30.4% at 4 years. Type II endoleak predominated. Leak from failure to completely occlude contralateral iliac flow accounted for 8 of 58 endoleaks (13.8%) at discharge. Sixteen patients (14.2%) underwent postoperative endoleak treatment; in one of these patients open conversion was necessary at 20 months. Post-procedure thigh or buttock claudication developed in 16 patients (14.2%). Thirteen patients (81.3%) had either distal attachment in the external iliac artery or contralateral type IIA occlusion. Fifteen patients (13.3%) required intervention because of reduced limb flow; one of these patients underwent open conversion at 27 months, and another underwent axillofemoral grafting at 28 months. Device migration was confirmed in 2 (1.8%) patients, without current clinical sequelae. Whereas no femorofemoral graft thromboses occurred, graft infection developed in 3 patients (2.6%). During follow-up, aneurysm in 2 patients ruptured. Late death occurred in 41 patients (36.3%). Twenty-four patients (58.5%) died of cardiopulmonary disease; one death was endograft-related after aneurysm rupture; and one death was related to femorofemoral bypass infection. Actuarial survival was 78.4% (95% confidence interval [CI], 71%-86%) at 2 years and 63.4% (95% CI, 54%-73%) at 4 years. CONCLUSIONS In patients with significant comorbid conditions and complex iliac anatomy unfavorable for bifurcated endografting, AI with femorofemoral bypass grafting is safe and effective. In most patients this endovascular option provides satisfactory mid-term results.

Surgical Response to Multiple Casualty Incidents Following Single Explosive Events

Background:Modern publications on response to single explosive events are from non-US hospitals, predate current resuscitation guidelines and lack detail on surgical and intensive care unit (ICU) requirements. The objective of this study is to provide a contemporary account of surge response to multiple casualty incidences following explosive events managed at a US trauma hospital in Iraq. Methods:Observational study and retrospective chart review of 72-hour transfusion, operating room, and ICU resource utilization from 3 multiple casualty incidences managed at the US Air Force Theater Hospital, Balad AB, Iraq between February and April 2008. Results:Fifty patients were treated with a mean injury severity score of 19. Forty-eight percent (n = 24) of casualties required blood transfusion with 4 patients receiving 43% (N = 74 units) of the packed red blood cells (pRBC). An average of 3.5 and 3.8 units of pRBC and plasma, respectively, was transfused per casualty (pRBC:plasma ratio of 1:1.1). Seventy-six percent (n = 38) of patients required immediate operation upon initial presentation. A total of 191 procedures were performed in parallel during 75 operations (3.8 procedures per casualty). Fifty percent (n = 25) of patients required ICU admission with nearly the same number (n = 24) requiring mechanical ventilator support beyond that required for operation. All cause, in-hospital mortality was 8% (n = 4). Conclusions:Results from this study provide a contemporary assessment of transfusion, surgical, and intensive care resource requirements after a single explosive event. Data from this experience may translate into useful guidelines for emergency planners worldwide.

Rapidly Enlarging Iliac Aneurysm Secondary to Listeria Monotogenes Infection A Case Report

Infected aneurysms caused by Listeria monocytogenes are rare. Worldwide, 16 cases have been reported, none in the iliac system. The authors report the case of an 80-year-old man being followed for small aortic and right common iliac artery (RCIA) aneurysms who presented with progressive gastrointestinal symptoms. Serial computed tomography demonstrated a 200% increase in RCIA diameter with development of infection over 1 month. Right axillobifemoral bypass and aneurysm resection were performed. The authors believe this case represents the first description of bacteremic seeding of an iliac degenerative aneurysm by Listeria monocytogenes. The natural history and aggressive course of vascular infection with this organism are documented.

Thoracic aortic endografting for trauma: a current appraisal.

OBJECTIVE To explore this newer treatment modalitys benefits, technical concerns, and complications as currently understood during the management of patients with blunt aortic injury (BAI). DATA SOURCES Data sources included relevant articles from published medical journals and current published texts. STUDY SELECTION Assimilation of the pertinent worlds literature into a select representation of the current status of thoracic aortic endografting for traumas (TAET) performance and outcomes. DATA EXTRACTION Comprehensive review of the current literature on BAI. DATA SYNTHESIS Comparison and critical evaluation of the current literature. CONCLUSIONS Endografting is the most frequently used method for repair of BAI. The use of TAET has led to reductions in operative mortality and spinal cord ischemia. Although experience seems promising, a new array of early and late complications must be considered. The positive experience with TAET thus far has provided impetus for endograft engineering and clinical trials specifically for BAI therapy. The ultimate late durability of TAET remains to be defined.

Predictors of late aortic intervention in patients with medically treated type B aortic dissection

Background Patients with medically managed type B aortic dissection (TBAD) have a high incidence of aorta‐related complications over time. Whereas early thoracic endovascular aortic repair (TEVAR) to seal the entry tear can promote aortic remodeling and prevent late aneurysm formation, there are sparse data as to which patients will benefit from such therapy. The goal of this study was to identify clinical and anatomic factors that are associated with the need for subsequent aortic intervention in patients who present with uncomplicated TBAD. These factors could guide the selection of patients who will benefit from TEVAR in the subacute phase. Methods Patients who presented with acute uncomplicated TBAD and were initially managed medically from January 2000 to December 2013 were included in the study. Timing of intervention was stratified into early (within 180 days of initial presentation) and late (181 days and later) cohorts. All patients had follow‐up axial imaging studies. These imaging studies were reviewed for anatomic criteria in a retrospective fashion. Predictors of aortic intervention were determined using Cox regression analyses. Results There were 254 patients (65% men) with medically managed acute TBAD. The average age at presentation was 66.3 years, and 82.5% had a history of hypertension. Mean follow‐up was 6.8 years (range, 0.1‐13.6 years). There were a total of 97 (38%) patients who required an aortic intervention during follow‐up; 30 (12%) patients required an early intervention, and 67 (26%) were treated during late follow‐up (100% for aneurysmal degeneration). Predictors of late aortic intervention included entry tear >10 mm (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.5‐3.8; P = .03), total aortic diameter >40 mm at time of presentation (OR, 2.2; 95% CI, 1.8‐4.3; P = .02), false lumen diameter >20 mm (OR, 1.8; 95% CI, 1.3‐4.7; P = .03), and increase in total aortic diameter >5 mm between serial imaging studies (OR, 2.3; 95% CI, 1.3‐3.5; P = .02). Complete thrombosis of the false lumen was protective against late operative intervention (OR, 0.22; 95% CI, 0.11‐0.48; P < .01). Conclusions Nearly 40% of patients who present with an uncomplicated TBAD will ultimately require an aortic intervention. All of the late interventions were performed for aneurysmal degeneration. A variety of readily available anatomic features can predict the need for eventual operative intervention in TBAD; accordingly, these parameters can guide the desirability of early TEVAR.

Endovascular versus open management of blunt traumatic aortic disruption at two military trauma centers: comparison of in-hospital variables.

BACKGROUND Blunt traumatic aortic disruption (BTAD) carries significant mortality and morbidity. Traditional open repair has appreciable risks of perioperative mortality and spinal cord ischemic complications. Endovascular repair may reduce the incidence of these adverse outcomes. We present the experience at two military trauma centers with thoracic aortic endografting for trauma (TAET) and compare this with recent open experience. METHODS A review of inpatient records was performed. All patients undergoing open repair or TAET for acute BTAD were studied. Collected data included demographics, injury characteristics, and in-hospital variables. Descriptive statistics were calculated with two-tailed t-tests performed for comparison of continuous variables. RESULTS Five open and eight TAET repairs were performed. Mean age was 32 years (range 28-50) in the TAET group and 35 (25-57) in the open group. All patients, except one TAET, had at least one associated injury with thoracic injuries predominating. Twelve BTAD were just distal to the left subclavian artery. One injury, treated with TAET, was just proximal to the celiac. Operative blood loss averaged 298 +/- 394 mL in the TAET group vs. 2,400 +/- 3,800 mL in the open group (p = 0.18). Crystalloid infusions were similarly reduced in TAET patients, 1,019 +/- 532 mL vs. 4,860 +/- 1,547 mL, p < 0.05), as were red blood cell transfusions, 1.6 units vs. 5.0 units (p = 0.12). The majority of patients [6/8 (75%) TAET, 5/5 (100%) open] experienced an inpatient complication (p = 0.09). All open patients had at least one infectious complication. There were no inpatient deaths related to aortic injury or spinal cord ischemic complications. CONCLUSIONS TAET is feasible for the treatment of BTAD in military trauma centers. It is important for military centers to accomplish this with adequate results as endovascular technologies are now being taken to the battlefield. Decreased blood loss and resuscitation requirements compared to open repair are likely contributors to improved outcomes with TAET.

Biochemical markers of acute limb ischemia, rhabdomyolysis, and impact on limb salvage

Biochemical markers of ischemia reperfusion injury have been of interest to vascular surgeons and researchers for many years. Acute limb ischemia is the quintessential clinical scenario where these markers would seem relevant. The use of biomarkers to preoperatively or perioperatively predict which patients will not tolerate limb-salvage efforts or who will have poor functional outcomes after salvage is of immense interest. Creatinine phosphokinase, myoglobin, lactate, lactate dehydrogenase, potassium, bicarbonate, and neutrophil/leukocyte ratios are a few of the studied biomarkers available. Currently, the most well-studied aspect of ischemia reperfusion injury is rhabdomyolysis leading to acute kidney injury. The last 10 years have seen significant progression and improvement in the treatment of rhabdomyolysis, from minor supportive care to use of continuous renal replacement therapy. Identification of specific biomarkers with predictive outcome characteristics in the setting of ischemia reperfusion injury will help guide therapeutic development and potentially mitigate pathophysiologic changes in acute limb ischemia, including rhabdomyolysis. These may further lead to improvements in short- and long-term surgical outcomes and limb salvage, as well as a better understanding of the timing and selection of intervention.

Use of extracorporeal bypass is associated with improved outcomes in open thoracic and thoracoabdominal aortic aneurysm repair

Objective: There is no consensus on the use or benefit of extracorporeal circulation (EC) during aneurysm repair of the descending thoracic aorta (DTA) or thoracoabdominal aorta (TAA). We evaluated the role of EC during DTA or TAA aneurysm repair using U.S. Medicare data. Methods: Medicare (2004‐2007) patients undergoing open repair of nonruptured DTA or TAA aneurysm were identified by International Classification of Diseases, Ninth Revision code. Specific exclusions included ascending aortic or arch repairs, concomitant cardiac procedures, and procedures employing deep hypothermic circulatory arrest. The impact of EC (code 3961) on early and late outcomes was analyzed using univariate analysis and multivariable regression. Survival was assessed using Kaplan‐Meier analysis and Cox proportional hazards regression models. Results: There were 4230 patients who had repair of intact DTA or TAA aneurysms, 2433 (57%) of which employed EC. Differences in baseline clinical features of EC and non‐EC patients showed that patients undergoing aortic reconstruction with EC were older (73 ± 1 years vs 72 ± 1 years; P = .002), were more likely to be female (53% vs 47%; P < .001), and had more hypertension (56% vs 53%; P = .02); they had less chronic obstructive pulmonary disease (28% vs 34%; P < .0001), peripheral vascular disease (5.7% vs 11.3%; P < .001), and chronic kidney disease (7.7% vs 5.5%; P = .003). The 30‐day mortality (9.7% for EC vs 12.2%; P = .02) and any major complication (49% for EC vs 58%; P < .001) were significantly reduced with EC use. EC use was associated with a shorter length of stay (13.5 ± 13 days vs 17.2 ± 18 days; P < .01) and lower total hospital charges (

Select early type IA endoleaks after endovascular aneurysm repair will resolve without secondary intervention

151,000 ± 140,000 vs

Characterization of perioperative contralateral stroke after carotid endarterectomy

180,000 ± 190,000; P < .01) compared with non‐EC patients. EC patients were more likely to be discharged home instead of to an extended care facility (67% vs 56%; P < .01). Multivariable regression modeling to adjust for baseline clinical differences showed EC to independently reduce the risk of operative mortality (odds ratio [OR], 0.80; 95% confidence interval [CI], 0.65‐0.97; P = .02), any complication (OR, 0.67; 95% CI, 0.59‐0.76; P < .01), pulmonary complications (OR, 0.68; 95% CI, 0.59‐0.79; P < .01), and acute renal failure (OR, 0.52; 95% CI, 0.44‐0.61; P < .01). Long‐term survival was higher (log‐rank, P < .01) in EC patients at 1 year (81% ± 0.8% vs 73% ± 1%) and 5 years (67% ± 1% vs 52% ± 1%). Risk‐adjusted Cox proportional hazards regression also showed that EC was independently associated with improved long‐term survival (hazard ratio, 0.69; 95% CI, 0.63‐0.74; P < .01). Conclusions: Although important clinical variables such as DTA or TAA aneurysm extent and spinal cord ischemic complications cannot be assessed with the Medicare database, EC use during open DTA and TAA aneurysm repair is associated with improved late survival and a significant reduction in operative mortality, morbidity, and procedural costs. These data indicate that EC should be a more widely applied adjunct in open DTA or TAA aneurysm repair.