Rebecca Kelso

Late conversion of aortic stent grafts

OBJECTIVES The frequency of late removal of endovascular abdominal aortic repair (EVAR) parallels the rise of endovascular aortic repair. Evaluation of outcomes for EVAR explants may identify risks for complications and alter clinical management. METHODS A patient database was used to identify EVAR patients requiring explant >1 month after implant. A retrospective analysis was conducted of the type of graft, duration of implant, reason for removal, operative technique, death, and length of stay. RESULTS During 1999 through 2007, 1606 EVARs were performed, and 25 patients required explantation, with an additional 16 referred from other institutions (N = 41). The average age was 73 years (range, 50-87 years); 90% were men. Grafts were excised after a median of 33.3 months (range, 3-93 months). Explanted grafts included 16 AneuRx (40%), 7 Ancure (17%), 6 Excluder (15%), 4 Zenith (10%), 4 Talent (10%), 1 Cook Aortomonoiliac rupture graft, 1 Endologix, 1 Quantum LP, and 1 homemade tube graft. Overall hospital mortality was 19% and occurred after conversion for rupture in 4, and in infected graft, aortoenteric fistula, repair of new aneurysm of the visceral segment, and claudication due to graft stenosis in one patient each. Elective EVAR-related mortality was 3.3%. Mortality was higher in patients with rupture compared with nonrupture (4 of 6 vs 3 of 35, P <or= .01). Thirty patients (73%) had one or more endoleaks (type I, 16; II, 9; III, 9; endotension, 5). Migration (n = 10), rupture (n = 6), aortoenteric fistula (n = 3), infection (n = 1), limb thrombosis (n = 3), and claudication (n =1) were also factors. Proximal aortic control was above the endograft (supravisceral, 23; suprarenal, 12; infrarenal, 6). Reconstruction was an aortoiliac repair in 63% and tube graft in 25%. Grafts with suprarenal fixation required longer proximal aortic clamp time of 43 minutes vs 28 minutes for infrarenal fixation. Complete graft removal was achieved in 85%. Proximal or distal portions of the endograft were incorporated into the repair in the remaining six. CONCLUSION Elective EVAR conversion, although technically challenging may be done with mortality similar to primary open repair. Mortality for conversion for infected grafts and ruptured aneurysms remains high. EVAR is associated with continued risk of conversion, and surveillance may identify late complications that require removal, justifying lifelong monitoring. Aggressive management of late complications and elective conversion may minimize the mortality associated with this procedure.

Lower extremity amputations: factors associated with mortality or contralateral amputation.

Background: Tissue loss or gangrene in the setting of lower extremity peripheral artery disease (PAD) may result in amputation. Previous studies have demonstrated elevated mortality rates after major transtibial and transfemoral amputation. Also, amputation of 1 leg may be associated with subsequent major amputation of the contralateral leg. The aim of our study was to identify patient variables associated with mortality and contralateral amputation. Methods: We reviewed the medical records of patients who underwent transfemoral or transtibial amputation secondary to PAD from 2004 to 2009. A total of 454 consecutive major amputations were performed on 391 patients, with 63 of these having a subsequent contralateral amputation. Standard demographic information, comorbidities, prior vascular interventions, and relevant procedural information were extracted from patient records. Kaplan-Meier estimates of survival were calculated. Cox proportional hazard models were used to estimate the risk of death and contralateral amputation. Multivariate Cox proportional hazards models were fit for all variables shown to be marginally associated in the univariate model. Results: In 391 amputees, the mean age was 67.3 years, 63% were male and 62% were caucasian. Patients had high rates of diabetes (63%), hypertension (83%), renal insufficiency (35%), hyperlipidemia (51%), and prior ipsilateral vascular intervention (75%). Seventy percent of patients had below-knee amputations. Perioperative mortality was 9.2% (n = 36). Survival at 12 and 24 months was 70% (95% confidence interval [CI], 65%-74%) and 60% (95% CI, 55%-65%), respectively. Multivariate analysis demonstrated that several independent factors were detrimental to survival including chronic obstructive pulmonary disease (hazard ratio [HR] 1.82, P = .002), dialysis dependence (HR 2.50, P < .001), high cardiac risk (HR 2.20, P < .001), and guillotine amputation (HR 2.49, P = .004). Dialysis (HR 2.42, P = .002) and revision of the index ipsilateral amputation to a higher level (HR 2.02, P = .014) were associated with a subsequent contralateral amputation. Conclusions: Patients with advanced PAD that require lower extremity amputation have diminished survival and significant contralateral amputation rates. Elderly patients on dialysis are particularly prone to dying or losing the other leg after a major amputation. These data support strategies to enhance limb preservation and optimize medical comorbidities in these patients.

Flow Reversal for Cerebral Protection in Carotid Artery Stenting: A Review:

Carotid artery stenting has established itself as a valid treatment option for carotid stenosis. Many neuroprotective devices have been developed to minimize the risk of embolic events and stroke. Of the devices available today, flow reversal is unique in its conceptual similarity to carotid endarterectomy shunting techniques that maintain cerebral flow. This review focuses on the technical aspects, results, advantages, and disadvantages of carotid flow reversal for embolic protection during carotid artery stenting.

Progress in management of malperfusion syndrome from type B dissections

OBJECTIVE Malperfusion syndrome is a known predictor of poor outcomes in acute type B dissection. We describe our experience with revascularization in the acute setting. METHODS Patients undergoing intervention for ischemia complicated acute type B dissection between November 1999 and March 2011 were reviewed. Details of presenting condition, surgical intervention, and postoperative course were collected. Descriptive and inferential statistical analyses included survival and freedom from reintervention using Cox proportional hazards models. RESULTS A total of 61 patients were identified with malperfusion in at least one territory, including spinal cord 7/61 (12%), mesenteric 37/61 (61%), renal 45/61 (73%), and lower extremity 38/61 (62%). Thoracic stent grafts were placed in all patients, and 41% of patients required adjunctive branch vessel stenting. After intervention, resolution of the ischemia was reported in 57/61 (93%) of patients. The 30-day/in-hospital mortality was 21.3%. The 6-month, 1-year, and 5-year survival was 75% (95% CI, 65%-87%), 71% (95% CI, 61%-84%), and 56% (95% CI, 43%-74%), respectively. The 6-month, 1-year, and 5-year freedom from reintervention was 84% (95% CI, 75%-95%), 76% (95% CI, 65%-90%), and 42% (95% CI, 24%-76%), respectively. Territory of ischemia was not independently associated with mortality, but placement of a stent graft proximal to the subclavian artery was associated with poor outcome hazard ratio 2.91 (95% CI, 1.09-8.11; P = .034). CONCLUSIONS Malperfusion in any territory at the time of presentation in patients with type B dissections can be treated with endovascular intervention with acceptable outcomes. Opposed to branch vessel intervention alone, increased aortic intervention with regard to proximal coverage may signify more serious disease is associated with worse outcome.

Vascular Injuries During Anterior Exposure of the Thoracolumbar Spine

BACKGROUND The aim of this study was to evaluate the vascular injuries, repairs, and complications encountered during anterior thoracolumbar spine exposures. METHODS The medical records of patients undergoing anterior spine exposures from January 2004 to June 2010 were retrospectively analyzed. RESULTS A total of 269 anterior exposures were performed in 260 patients. The average patient age was 50.1 years, and the average body mass index was 29.0. Female patients represented 146 (54.3%) cases. Previous spinal surgery was noted in 145 (53.9%) cases, and 19 (7.1%) had previous anterior exposure. The median estimated blood loss (EBL) was 300 mL, and there were no postoperative mortalities. A vascular injury occurred in 37 cases (13.8%), with redo anterior exposure (n = 19, 52% vs. 11%; P < 0.001), previous spinal surgery (n = 145, 19% vs. 7%; P = 0.01), and diagnosis of a tumor (n = 14, 36% vs. 12.5%; P = 0.03) being associated with increased vascular injury. A vascular injury resulted in greater EBL (median: 800 mL vs. 300 mL; P < 0.001) and longer hospitalization (median: 7 days vs. 5 days; P = 0.04). Most frequently injured was the left common iliac vein (in 21 of the 37 [52.5%] injured cases). A vascular surgeon performed the exposure in 159 (59.1%) cases. There was a decrease in EBL (250 mL vs. 500 mL; P < 0.001), total incision time (290 minutes vs. 404 minutes; P = 0.002), and length of stay (5 days vs. 6.5 days; P < 0.001) as compared with the operations where the vascular surgeon was not involved in the exposure. These cases also had an increased incidence of any vascular injury (28 vs. 9; P = 0.04). There were no differences between groups regarding vascular injury type, repair type, or the incidence of deep venous thrombosis. CONCLUSION Collaboration between spine and vascular teams may result in decreased blood loss and consequently improved morbidity and length of hospital stay.