Patients with Acute Lower Limb Ischemia Continue to Have Significant Morbidity and Mortality.

BACKGROUND: The treatment of acute lower limb ischemia (ALLI) has evolved over the last several decades with the availability of several new treatment modalities. This study was undertaken to evaluate the contemporary presentation and outcomes of ALLI patients. METHODS: We retrospectively analyzed data from a prospectively collected database of all patients who presented to our tertiary referral hospital with acute ischemia of the lower extremity between May 2016 and October 2020. The cause of death was obtained from the Michigan State Death Registry. RESULTS: During the study period, 233 patients (251 lower limbs) were evaluated for ALLI. Seventy-three percent had thrombotic occlusion, 24% had embolic occlusion, and 3% due to a low flow state. Rutherford classification of ischemia severity was 7%, 49%, 40%, and 4% for Rutherford grade I, IIA, IIB, and III, respectively. Five percent underwent primary amputations, and 6% received medical therapy only. The mean length of stay was 11 ± 9 days. Nineteen percent of patients were readmitted within 30 days of discharge. At 30 days postoperatively, mortality was 9% and limb loss was 19%. On multivariate analysis, 1 or no vessel runoff to the foot postoperatively was associated with higher 30-day limb loss. Patients with no run-off vessels postoperatively had significantly higher 30-day mortality. Cardiovascular complications accounted for most deaths (48%). At 1-year postoperatively, mortality and limb loss reached 17% and 34%, respectively. CONCLUSIONS: Despite advances in treatment modalities and cardiovascular care, patients presenting with ALLI continue to have high mortality, limb loss, and readmission rates at 30 days.

Necessity, Role, and Outcomes of Fasciotomy in Patients with Acute Limb Ischemia.

BACKGROUND: The incidence of compartment syndrome in patients with acute lower limb ischemia (ALLI) and the effects of fasciotomy on outcomes are largely undefined. This study aimed to define the incidence of compartment syndrome in patients with ALLI and to examine whether different fasciotomy strategies are associated with specific patient outcomes. METHODS: A single-center retrospective study of patients who had ALLI between April 2016 and October 2020 at a tertiary care center. Patients were categorized into groups as having received early and late therapeutic fasciotomy (TF), early prophylactic fasciotomy (PF), early exploratory fasciotomy, and no fasciotomy. Primary outcome was 30-day amputation rate. Secondary outcomes were 30-day and 1-year mortality, 1-year amputation rate, and length of stay. Groups were compared using descriptive statistics to assess the association of fasciotomy approach with outcomes. RESULTS: During the study period, 266 patients were treated for ALLI, and 62 patients (23%) underwent 66 fasciotomies. A total of 41 TF, 23 PF, and 2 exploratory fasciotomies were done. There were 58 early fasciotomies performed (88% of 66 limbs): 33 (57%) early TF, 23 (40%) PF, and 2 (3%) exploratory. There were 8 patients who developed compartment syndrome after their revascularization operation and received delayed TF (12% of 66 limbs). The total number of TF was 41, which was 15% of all ALLI patients. The mean ± SD time to fasciotomy closure was 6.7 ± 5.7 days, which did not differ between PF and TF groups. Significantly more patients in the TF group had an amputation at 30 days (11 [29%] vs. 1 [5%]; P = 0.03) and at 1 year (6 [18%] vs. 2 [9%]; P = 0.02) than those in the PF group. Length of stay was increased in both TF (16 days) and PF (19 days) patients compared to nonfasciotomy patients (10 days; P < 0.01) but did not differ between the 2 fasciotomy groups (P = 0.4). Thirty-day limb loss was highest in patients who underwent early TF (10/33, 33%), intermediate in those with delayed TF (1/8, 13%), and lowest in PF (1/23, 5%; P = 0.03). CONCLUSIONS: Approximately 15% of patients with ALLI in our cohort required a TF for compartment syndrome. Close postoperative monitoring of ALLI patients who did not undergo early fasciotomy did detect delayed compartment syndrome; however, this approach did not prevent limb loss. To optimize limb salvage, physicians treating patients with ALLI should be experienced in how to recognize and treat compartment syndrome.

Impact of Preoperative Anemia on Hospitalization, Death, and Overall Survival in Patients With Peripheral Artery Disease Undergoing Endovascular Therapy: A Retrospective Cohort Study in the United States and Canada.

PURPOSE: Preoperative anemia is associated with adverse outcomes after cardiac and noncardiac surgeries, but outcomes after an endovascular peripheral vascular intervention (PVI) are not well established. We aimed to assess the association of preoperative anemia with 30 day death, hospital length of stay (LOS), and overall (long term) survival in patients undergoing an endovascular PVI for peripheral artery disease. MATERIALS AND METHODS: In this retrospective, cohort study in the United States and Canada, we queried the national Vascular Quality Initiative database for all endovascular PVIs performed between 2010 and 2019, and outcomes were correlated with patients' hemoglobin (Hb) levels. Anemia was classified as mild (Hb=10-13 g/dL for men and 10-12 g/dL for women), moderate (Hb=8-9.9 g/dL), and severe (Hb<8 g/dL). RESULTS: A total of 79 707 adult patients who met study criteria underwent endovascular PVI. The mean age was 68 years, and 59% of patients were male. Anemia was documented in 38 543 patients (48%) and was mild in 27 435 (71%), moderate in 9783 (25%), and severe in 1325 (4%). The median follow-up duration was 4 years (range, 1.25-5.78 years). On univariate analysis, 30 day mortality, total LOS, and overall survival were significantly associated with the level of preoperative anemia. These associations persisted in the multivariate models. Kaplan-Meier survival analysis demonstrated an association of death with degree of anemia (p<0.001). CONCLUSION: The presence and degree of preoperative anemia were independently associated with increased 30 day mortality and LOS and decreased overall survival for patients with peripheral artery disease who had undergone endovascular PVI. CLINICAL IMPACT: The findings from this study have many implications for how to approach vascular surgery in patients with variable hemoglobin levels. Our findings will strengthen our ability to conduct accurate preoperative risk stratification for patients undergoing peripheral vascular interventions. This may also mitigate healthcare expenditures if findings are applied in a way that can lower patient length of postoperative stay while also maintaining quality of care and patient safety. Our results will also serve as guidance for clinical trials, and future prospective trials should evaluate the effect of preoperative optimization of hemoglobin as a potentially modifiable risk factor for outcomes.

Outcome benefit of arterial duplex stent imaging after superficial femoral artery stent implantation.

OBJECTIVE: In-stent stenosis is a frequent complication of superficial femoral artery (SFA) endovascular intervention and can lead to stent occlusion or symptom recurrence. Arterial duplex stent imaging (ADSI) can be used in the surveillance for recurrent stenosis; however, its uniform application is controversial. In this study, we aimed to determine, in patients undergoing SFA stent implantation, whether surveillance with ADSI yielded a better outcome than in those with only ankle-brachial index (ABI) follow-up. METHODS: We performed a retrospective analysis of all patients undergoing SFA stent implantation for occlusive disease at a tertiary care referral center between 2009 and 2016. The patients were divided into those with ADSI and those with ABI follow-up only. Life-table analysis comparing stent patency, major adverse limb events (MALEs), limb salvage, and mortality between groups was performed. RESULTS: There were 248 patients with SFA stent implantation included, 160 in the ADSI group and 88 in the ABI group. Groups were homogeneous in clinical indications of claudication and critical limb-threatening ischemia (for ADSI, 39% and 61%; for ABI, 38% and 62%; P = .982) and TransAtlantic Inter-Society Consensus class A, B, C, and D lesions (for ADSI, 17%, 45%, 16%, and 22%; for ABI, 21%, 43%, 16%, and 20%; P = .874). Primary patency was similar between groups at 12, 36, and 56 months (ADSI, 65%, 43%, and 32%; ABI, 69%, 34%, and 34%; P = .770), whereas ADSI patients showed an improved assisted primary patency (84%, 68%, and 54%) vs ABI patients (76%, 38%, and 38%; P = .008) and secondary patency. There was greater freedom from MALEs in the ADSI group (91%, 76%, and 64%) vs the ABI group (79%, 46%, and 46%; P < .001) at 12, 36, and 56 months of follow-up. ADSI patients were more likely to undergo an endovascular procedure as their initial post-SFA stent implantation intervention (P = .001), whereas ABI patients were more likely to undergo an amputation (P < .001). CONCLUSIONS: In SFA stent implantation, patients with ADSI follow-up demonstrate an advantage in assisted primary patency and secondary patency and are more likely to undergo an endovascular reintervention. These factors are likely to have effected a decrease in MALEs, indicating the benefit of a more universal adoption of post-SFA stent implantation follow-up ADSI.

Contrast-induced nephropathy after peripheral vascular intervention: Long-term renal outcome and risk factors for progressive renal dysfunction.

OBJECTIVE: Contrast-induced nephropathy (CIN) is a frequently used quality outcome marker after peripheral vascular interventions (PVIs). Whereas the factors associated with CIN development have been well documented, the long-term renal effects of CIN after PVI are unknown. This study was undertaken to investigate the long-term (1-year) renal consequences of CIN after PVI and to identify factors associated with renal function deterioration at 1-year follow-up. METHODS: From 2008 to 2015, patients who had PVI at our institution (who were part of a statewide Vascular Interventions Collaborative) were queried for those who developed CIN. CIN was defined by the Collaborative as an increase in serum creatinine concentration of at least 0.5 mg/dL within 30 days after intervention. Preprocedural dialysis patients or patients without postprocedural creatinine values were excluded. Preprocedural, postprocedural, and 1-year serum creatinine values were abstracted and used to estimate glomerular filtration rate (GFR). ΔGFR was defined as preprocedural GFR minus 1-year GFR. Univariate and multivariate analyses for ΔGFR were performed to determine factors associated with renal deterioration at 1 year. RESULTS: From 2008 to 2015, there were 1323 PVIs performed; 881 patients met the inclusion criteria. Of these, 57 (6.5%) developed CIN; 47% were male, and 51% had baseline chronic kidney disease. CIN resolved by discharge in 30 patients (53%). Using multivariate linear regression, male sex (P = .027) and congestive heart failure (P = .048) were associated with 1-year GFR decline. Periprocedural variables related to 1-year GFR decline included percentage increase in 30-day postprocedural creatinine concentration (P = .025), whereas CIN resolution by discharge (mean, 13.1 days) was protective for renal function at 1 year (P = .02). A post hoc analysis was performed with 50 PVI patients (randomly selected) who did not develop CIN, comparing their late renal function with that of the CIN group stratified by the periprocedural 30-day variables. Patients with CIN resolution at discharge had similar 1-year renal outcomes to non-CIN patients, whereas the CIN-persistent (at discharge) patients had greater renal deterioration at 1 year compared with non-CIN patients (P = .016). CONCLUSIONS: Male sex and congestive heart failure are risk factors for further renal function decline in patients developing CIN after PVI. The magnitude and duration of increase in creatinine concentration (CIN persistence at discharge) correlated with late progressive renal dysfunction in CIN patients, suggesting that early-resolving CIN is relatively benign.

Cryopreserved Allograft in the Management of Native and Prosthetic Aortic Infections.

BACKGROUND: The management of patients with aortic native and prosthetic infections is associated with significant morbidity and mortality. We describe a single-center experience with the use of cryopreserved allografts for the treatment of aortic infections, and compare outcomes with rifampin-soaked grafts and extra-anatomic bypass. METHODS: We retrospectively reviewed all patients who underwent an operative intervention for aortic infection at our tertiary care center from August 2007 to August 2017. Demographic data, preoperative work-up, procedural details, and outcomes were collected for each treatment modality. RESULTS: Thirty-two patients had aortic revascularization for aortic infection. Seventeen patients had cryopreserved allografts, 10 had rifampin-soaked grafts, and 5 had extra-anatomic bypass. Sixteen patients (50%) had native aortic infection and 16 patients (50%) had prosthetic aortic infection. Eighteen had involvement of the infrarenal abdominal aorta, 12 of the paravisceral aorta, and 2 of the descending thoracic aorta. Early mortality was 5.9% (1/17) for the cryopreserved group, 10% (1/10) for the rifampin-soaked group, and 40% (2/5) for the extra-anatomic bypass group. Early graft-related complications occurred in 1 patient (cryopreserved group). Mean follow-up was 34.8 months. Late death occurred in 4 patients with cryopreserved allografts, 2 with rifampin-soaked grafts and none with extra-anatomic bypass. Late graft-related complications occurred in 4 patients (cryopreserved group). Only 1 patient had recurrence of aortic infection (cryopreserved group) and 2 patients had limb loss (1 from the cryopreserved group and 1 from the rifampin-soaked group). At 1 month, 6 months, 1 year, and 3 years, estimated survival for patients with cryopreserved allografts was 94%, 82%, 75%, and 64%, respectively. CONCLUSIONS: The management of aortic infections is challenging. In patients who do not need immediate intervention, in situ aortic reconstruction with cryopreserved allografts is a viable treatment modality with relatively low morbidity and mortality.

Survival after abdominal aortic aneurysm repair is affected by socioeconomic status.

OBJECTIVE: The association between socioeconomic status (SES) and outcome after abdominal aortic aneurysm (AAA) repair is largely unknown. This study aimed to determine the influence of SES on postoperative survival after AAA repair. METHODS: Patients undergoing surgical treatment of AAA at a tertiary referral center between January 1993 and July 2013 were retrospectively collected. Thirty-day postoperative mortality and long-term mortality were documented through medical record review and the Michigan Social Security Death Index. SES was quantified using the neighborhood deprivation index (NDI), which is a standardized and reproducible index used in research that summarizes eight domains of socioeconomic deprivation and is based on census tracts derived from patients' individual addresses. The association between SES and survival was studied by univariable and multivariable Cox regression analysis. RESULTS: A total of 767 patients were included. The mean age was 73 years; 80% were male, 77% were white, and 20% were African American. There was no difference in SES of patients who underwent open vs endovascular repair of AAA (P = .489). The average NDI was -0.18 (minimum, -1.47; maximum, 2.35). After adjusting for the variables that were significant on univariable analysis (age, medical comorbidities, length of stay, and year of surgery), the association between NDI and long-term mortality was significant (P = .021; hazard ratio, 1.21 [1.05-1.37]). CONCLUSIONS: Long-term mortality after AAA repair is associated with SES. Further studies are required to assess which risk factors (behavioral, psychosocial) are responsible for this decreased long-term survival in low SES patients after AAA repair.

Cerebrovascular injuries found in acute type B aortic dissections are associated with blood pressure derangements and poor outcome.

OBJECTIVE: Cerebrovascular injury (CVI) is a recognized but underappreciated complication of acute type B aortic dissection (ATBAD). This study was performed to determine risk factors for CVI associated with ATBAD and, in particular, the possible contributory role of aggressive anti-impulse therapy. METHODS: A retrospective review of all patients presenting to a tertiary medical center with an ATBAD between January 2003 and October 2012 was conducted. All CVIs were adjudicated by a vascular neurologist and assigned a probable cause. The initial intensity of anti-impulse therapy was defined as the difference in mean arterial pressure (ΔMAP) from presentation to subsequent admission to the intensive care unit. RESULTS: A total of 112 patients were identified. The average age was 61 years; 64% were male, and 59% were African American. Twenty patients required operative intervention (14 thoracic endovascular aortic repairs and 6 open). CVI occurred in 13 patients (11.6%): 9 were hypoperfusion related (6 diffuse hypoxic brain injuries and 3 watershed infarcts), 2 were procedure related (both thoracic endovascular aortic repairs), 1 was an intracranial hemorrhage on presentation, and 1 was a probable embolic stroke on presentation. CVI patients had demographics and comorbidities comparable to those of the non-CVI patients. CVI was associated with operative intervention (54% vs 13%; P = .002). Thirty-day mortality was significantly higher in CVI patients (54% vs 6%; P < .001). Patients who suffered a hypoperfusion brain injury had a higher MAP on presentation to the emergency department (142 mm Hg vs 120 mm Hg; P = .034) and a significantly greater reduction in MAP (ΔMAP 49 mm Hg vs 15 mm Hg; P < .001) by the time they reached the intensive care unit compared with the non-CVI patients. CONCLUSIONS: In our series, CVI in ATBAD is more frequent than previously reported and is associated with increased mortality. The most common causes are related to cerebral hypoperfusion. Higher MAP on presentation and greater decline in MAP are associated risk factors for hypoperfusion-related CVI. A less aggressive approach to lowering MAP in ATBAD warrants further study in an attempt to reduce CVI in ATBAD.

Long-term decline in renal function is more significant after endovascular repair of infrarenal abdominal aortic aneurysms.

OBJECTIVE: It is not clear whether endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs) results in an increase in renal insufficiency during the long term compared with open repair (OR). We reviewed our experience with AAA repair to determine whether there was a significant difference in postoperative and long-term renal outcomes between OR and EVAR. METHODS: A retrospective cohort study was conducted of all patients who underwent AAA repair between January 1993 and July 2013 at a tertiary referral hospital. Demographics, comorbidities, preoperative and postoperative laboratory values, morbidity, and mortality were collected. Patients with ruptured AAAs, preoperative hemodialysis, juxtarenal or suprarenal aneurysm origin, and no follow-up laboratory values were excluded. Preoperative, postoperative, 6-month, and yearly serum creatinine values were collected. Glomerular filtration rate (GFR) was calculated on the basis of the Chronic Kidney Disease Epidemiology Collaboration equation. Acute kidney injury (AKI) was classified using the Kidney Disease: Improving Global Outcomes guidelines. Change in GFR was defined as preoperative GFR minus the GFR at each follow-up interval. Comparison was made between EVAR and OR groups using multivariate logistics for categorical data and linear regression for continuous variables. RESULTS: During the study period, 763 infrarenal AAA repairs were performed at our institution; 675 repairs fit the inclusion criteria (317 ORs and 358 EVARs). Mean age was 73.9 years. Seventy-nine percent were male, 78% were hypertensive, 18% were diabetic, and 31% had preoperative renal dysfunction defined as GFR below 60 mL/min. Using a multivariate logistic model to control for all variables, OR was found to have a 1.6 times greater chance for development of immediate postoperative AKI compared with EVAR (P = .038). Hypertension and aneurysm size were independent risk factors for development of AKI (P = .012 and .022, respectively). Using a linear regression model to look at GFR decline during several years, there was a greater decline in GFR in the EVAR group. This became significant starting at postoperative year 4. AKI and preoperative renal dysfunction were independent risk factors for long-term decline in renal function. CONCLUSIONS: Although AKI is less likely to occur after EVAR, patients undergoing EVAR experience a significant but delayed decline in GFR over time compared with OR. This became apparent after postoperative year 4. Studies comparing EVAR and OR may need longer follow-up to detect clinically significant differences in renal function.

Association of Anemia With Outcomes in Patients Undergoing Percutaneous Peripheral Vascular Intervention: Insights From the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2 VIC).

OBJECTIVES: To evaluate the clinical features and outcomes of patients with anemia undergoing percutaneous peripheral vascular intervention (PVI) in a contemporary registry. METHODS: We evaluated the differences in the clinical features and outcomes of patients with and without anemia undergoing PVI in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2 VIC) registry. Anemia was defined using World Health Organization criteria. RESULTS: Baseline anemia was present in 42.3% of 15,683 patients undergoing PVI. Compared to patients without anemia, those with anemia were older (mean age, 67 years vs 71 years), were more often black (16% vs 29%), and had higher comorbidities. Anemic patients were twice as likely to present with acute limb ischemia (5% vs 11%) and undergo urgent PVI (6% vs 15%) or below-the-knee PVI (18% vs 35%). Many in-hospital adverse events were higher in anemic patients. In a propensity-matched cohort, any adverse outcome (3.4% vs 8.4%; odds ratio [OR], 2.58; 95% confidence interval [CI], 1.94-3.42) or major cardiovascular event, defined as death, myocardial infarction, stroke, or amputation (1.1% vs 3.2%; OR, 2.96; 95% CI, 1.83-4.79) was more likely in anemic patients. Of all adverse events, the highest odds were observed for post-PVI transfusions and amputations in anemic patients. Multivariable logistic regression showed that baseline hemoglobin (1 g/dL below the normal value) was associated with greater risk of any adverse event (OR, 1.57; 95% CI, 1.47-1.68). CONCLUSION: The prevalence of anemia was high among PVI patients and was associated with significantly greater likelihood of amputation, any adverse event, and major cardiovascular events. Whether preprocedure correction of anemia has the potential to decrease post-PVI adverse events remains to be studied.

Predictors of surgical site infection after open lower extremity revascularization.

OBJECTIVE: Surgical site infection (SSI) after open lower extremity bypass (LEB) is a serious complication leading to an increased rate of graft failure, hospital readmission, and health care costs. This study sought to identify predictors of SSI after LEB for arterial occlusive disease and also potential modifiable factors to improve outcomes. METHODS: Data from a statewide cardiovascular consortium of 35 hospitals were used to obtain demographic, procedural, and hospital risk factors for patients undergoing elective or urgent open LEB between January 2012 and June 2015. Bivariate comparisons and targeted maximum likelihood estimation were used to identify independent risk factors of SSI. Adjusted odds ratios (ORs) were calculated for patient demographics, comorbidities, operative details, and hospital-level factors. RESULTS: Our study population included 3033 patients who underwent 703 femoral-femoral bypasses, 1431 femoral-popliteal bypasses, and 899 femoral-distal vessel bypasses. An SSI was diagnosed in 320 patients (10.6%) ≤30 days after the index operation. Adjusted patient and procedural predictors of SSI included renal failure currently requiring dialysis (OR, 4.35; 95% confidence interval [CI], 3.45-5.47; P < .001), hypertension (OR, 4.29; 95% CI, 2.74-6.72; P < .001), body mass index ≥25 kg/m2 (OR, 1.78; 95% CI, 1.23-2.57; P = .002), procedural time >240 minutes (OR, 2.95; 95% CI, 1.89-4.62; P < .001), and iodine-only skin preparation (OR, 1.73; 95% CI, 1.02-2.91; P = .04). Hospital factors associated with increased SSI included hospital size <500 beds (OR, 2.22; 95% CI, 1.09-4.55; P = .028) and major teaching hospital (OR, 1.66; 95% CI, 1.07-2.58; P = .024). SSI resulted in increased risk of major amputation and surgical reoperation (P < .01), but did not affect 30-day mortality. CONCLUSIONS: SSI after LEB is associated with an increase in rate of amputation and reoperation. Several patient, operative, and hospital-related risk factors that predict postoperative SSI were identified, suggesting that targeted improvements in perioperative care may decrease complications and improve vascular patient outcomes.

Contrast-induced nephropathy in patients undergoing endovascular peripheral vascular intervention: Incidence, risk factors, and outcomes as observed in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium.

BACKGROUND: The incidence, risk factors, and outcomes associated with Contrast-induced nephropathy (CIN) after Percutaneous Vascular Intervention (PVI) in contemporary medical practice are largely unknown. METHODS: A total of 13 126 patients undergoing PVI were included in the analysis. CIN was defined as an increase in serum creatinine from pre-PVI baseline to post-PVI peak Cr of ≥0.5 mg/dL. RESULTS: CIN occurred in 3% (400 patients) of the cohort, and 26 patients (6.5%) required dialysis. Independent predictors of CIN were high and low body weight, diabetes, heart failure, anemia, baseline renal dysfunction, critical limb ischemia, and a higher acuity of the PVI procedure and a contrast dose that was greater than three times the calculated creatinine clearance (CCC) (adjusted OR 1.4, 95% CI: 1.1-1.8, P = 0.003). CIN was strongly associated with adverse outcome including in-hospital death (adjusted OR 18.1, CI 10.7-30.6, P < 0.001), myocardial infarction (adjusted OR 16.2, CI 8.9-29.5, P < 0.001), transient ischemic attack/stroke (adjusted OR 5.5, CI 3.2-14.9, P = 0.001), vascular access complications (adjusted OR 3.4, CI 2.3-5, P < 0.001), and transfusion (adjusted OR 7, CI 5.4-9, P < 0.001). Hospital stay was longer in patients who developed CIN versus those who did not. CONCLUSIONS: CIN is not an uncommon complication associated with PVI, can be reliably predicted from pre-procedural variables, including a contrast dose of greater than three times the CCC and is strongly associated with the risk of in-hospital death, MI, stroke, transfusion, and increased hospital length of stay.

Socioeconomic disparities affect survival after aortic dissection.

OBJECTIVE: The effect of socioeconomic status (SES) on the course of many disease states has been documented in the literature but has not been studied in aortic dissection. This study evaluated the effect of SES on 30-day and long-term survival of patients after aortic dissection. METHODS: Hospital discharge records were used to identify patients with acute aortic dissection. Patient demographics, insurance status, comorbidities, and 30-day mortality were collected. Home addresses were used to estimate each patient's median household income, and the neighborhood deprivation index, a measure of SES, was determined. Long-term survival was assessed by review of the Social Security Death Index. Associations between demographics, insurance status, comorbidities, and poverty level were investigated to determine their effect on survival. RESULTS: There were 212 aortic dissections; of which, 118 were type A and 94 were type B. Median follow-up was 7.6 years. The neighborhood deprivation index (hazard ratio, 1.43; 95% confidence interval, 1.16-1.78; P = .001) was associated with reduced long-term survival and was also significantly associated with 30-day mortality (hazard ratio, 1.43; 95% confidence interval, 1.05-1.93; P = .02). The mean neighborhood deprivation index score was higher in patients with type B aortic dissections (0.45 ± 0.93) than in those with type A aortic dissections (0.16 ± 0.96; P = .029). CONCLUSIONS: Patients with a lower SES had reduced short-term and long-term survival after aortic dissection. Patients with type B dissection live in lower socioeconomic neighborhoods than patients with type A dissection.

Survival after repair of pararenal and paravisceral abdominal aortic aneurysms.

OBJECTIVE: The objective of this study was to review our 27-year clinical experience with open proximal abdominal aortic aneurysm repairs, with a focus on long-term survival. METHODS: A retrospective cohort study was undertaken of all patients who underwent proximal abdominal aortic aneurysm repair between 1986 and 2013 at a tertiary care referral center. Demographics, operative variables, complications, and 30-day mortality were analyzed. Postoperative acute kidney injury was analyzed by the RIFLE (Risk, Injury, Failure, Loss, End-stage renal disease)/Acute Kidney Injury Network criteria. Long-term survival was assessed through review of electronic medical records and the Social Security Death Index. Associations between demographics and complications were investigated to determine predictors of long-term survival. RESULTS: The study identified 245 patients. Mean age was 71 years (range, 38-92 years); 69% were men, and 88% were white. Aneurysm type was juxtarenal in 127 patients (52%), suprarenal in 68 patients (28%), and type IV thoracoabdominal in 50 patients (20%). In-hospital mortality was 3.3% (eight patients), and 30-day mortality was 2.9% (seven patients). At least one major complication occurred in 64% of the patients, which included the following: acute kidney injury, 60% (persistent acute kidney injury at discharge, however, was 28%, and hemodialysis at discharge was 1.6%); major pulmonary complications, 22%; myocardial infarction, 4%; visceral ischemia, 2%; and paraplegia, 0.5%. Median follow-up was 54 months. Kaplan-Meier survival estimates were 70% at 5 years and 43% at 10 years. Variables associated with poorer survival included congestive heart failure (hazard ratio [HR], 3.5; P < .001), chronic obstructive pulmonary disease (HR, 1.8; P < .002), and increased aneurysm size at presentation (HR, 1.1; P < .013). Persistent stage 3 acute kidney injury was associated with poor long-term survival. CONCLUSIONS: Open surgical repair of proximal abdominal aortic aneurysms can be performed with low mortality. Acute kidney injury is the most frequent complication, but the need for hemodialysis at discharge is low. Long-term survival is favorable. These data should assist in establishing benchmarks for endovascular repair of complex proximal abdominal aortic aneurysms.

Changing presentation of knee dislocation and vascular injury from high-energy trauma to low-energy falls in the morbidly obese.

OBJECTIVE: Reports in the literature of low-energy (LE) knee dislocation (KD) in obese patients have been increasing. This study was undertaken to define the risk factors for KD by LE mechanisms and the outcomes of these patients compared with those with high-energy (HE) trauma. METHODS: All patients with a complete KD presenting to the emergency department of a large urban level I trauma center were reviewed. Patient information collected included age, sex, weight, height, body mass index (BMI), injury mechanism, neurovascular and orthopedic injuries, and operations performed to treat vascular injuries. Risk factors for KD and concomitant injuries were compared between HE traumatic dislocations and LE dislocations in obese patients (BMI >30 kg/m(2)), including stratification for increasing levels of obesity. RESULTS: Between January 1995 and April 2012, 53 patients with KD were identified. The mechanism of injury was HE in 28 (53%) and LE in 25 (47%). Of the LE KDs, 18 (72%) were related to obesity (BMI >30 kg/m(2)). Obese patients with LE trauma were more likely to have associated nerve injuries (50% vs 6%; P < .001), vascular injuries requiring intervention (33% vs 9%; P = .048), and vascular surgical repairs (28% vs 6%; P = .038) than patients with HE traumatic dislocations. These rates were highest in the patients with a BMI >40 kg/m(2). Although all LE KDs in the obese involved an isolated extremity, the hospital lengths of stay were comparable to those with HE KDs who frequently had multisystem trauma (8.7 vs 11.4 days). During a 17-year period, LE KDs in the obese represented an increasing proportion, from 17% in 1995 to 2000 up to 53% in 2007 to 2012, and the eventual majority of all KDs at our institution (P = .024). CONCLUSIONS: LE KDs in obese patients are becoming increasingly prevalent. These patients are more likely to have nerve and vascular injuries and are more likely to undergo vascular repair than patients with HE trauma. The epidemic of obesity in the United States presents unique challenges in the identification and treatment of patients with LE KD and their associated injuries.

The quality and impact of risk factor control in patients with stable claudication presenting for peripheral vascular interventions.

BACKGROUND: Peripheral arterial disease is a manifestation of systemic atherosclerosis and is predictive of future cardiovascular events. Clinical trial data have demonstrated that medical therapy can attenuate cardiovascular morbidity and mortality in patients with peripheral arterial disease. The utilization and impact of recommended medical therapy in a contemporary population of patients who undergo percutaneous interventions for lifestyle-limiting peripheral arterial disease is unknown. METHODS AND RESULTS: Using the Blue Cross Blue Shield of Michigan Cardiovascular Consortium Peripheral Vascular Intervention (BMC2 PVI) database, we identified 1357 peripheral vascular intervention encounters between January 2007 and December 2009 for the purpose of treating claudication. Before the intervention, 85% of these patients used aspirin, 76% used statin, 65% abstained from smoking, and 47% did all 3. There was no difference in cardiovascular events among those taking an aspirin and a statin on admission and those who were not. However, in both an unadjusted and a multivariable analysis, the odds of an adverse peripheral vascular outcome (repeat peripheral intervention, amputation, or limb salvage surgery) within 6 months decreased by more than half in patients receiving aspirin and statin therapy before peripheral vascular intervention as compared with those who received neither (odds ratio, 0.45; 95% CI, 0.29-0.71). CONCLUSIONS: The fundamental elements of medical therapy in patients with lifestyle-limiting claudication are often underutilized before referral for revascularization. Appropriate medical therapy before percutaneous revascularization is associated with fewer peripheral vascular events at 6 months.

Late endovascular aneurysm repair infection presenting with juxatrenal aortic rupture treated with in situ aortic replacement.

Infection of an endovascular abdominal aneurysm repair (EVAR) is rare but has become more prevalent with the standardization of EVAR for treating infrarenal abdominal aortic aneurysms. The understanding of this complex aortic condition has improved but still remains to evolve. We present a patient with an EVAR infection manifesting with juxtarenal aortic rupture as a result of a urinary tract infection. This report describes an unusual presentation of an EVAR infection treated with in situ aortic reconstruction and provides >1 year of follow-up.

Frequency, risk factors, and management of perigraft seroma after open abdominal aortic aneurysm repair.

OBJECTIVE: Perigraft seroma (PGS) causing enlargement of the native aneurysm sac after open abdominal aortoiliac aneurysm (AAA) repair is a rarely recognized complication with unknown clinical consequences. This study was undertaken to determine the frequency of PGS, identify associated risk factors, and review resulting complications and their management strategies. METHODS: Charts of all patients who underwent open AAA repair at our institution from 1995 to 2009 and had at least one postoperative abdominal cross-sectional imaging study (the study subjects) were retrospectively reviewed. PGS was defined as a perigraft fluid collection present > 3 months postoperatively, ≥ 3-cm in diameter and having a radiodensity ≤ 25 Hounsfield units on computed tomography (CT). Patient records were reviewed for demographics, comorbidities, operative and postoperative variables, and long-term outcome. RESULTS: Of the 111 study subjects identified, 13 had aortic reconstruction with Dacron grafts and 98 with polytetrafluoroethylene (PTFE) grafts. Twenty patients (18%) had PGS, all of whom had PTFE grafts (20 of 98; 20.4%). Mean age was 68.5 years and mean aneurysm diameter preoperatively was 6.4 cm (range, 4.0-10.9 cm). The average time from AAA repair to PGS detection was 51 months (range, 4-156 months). PGS averaged 6.0-cm in diameter (range, 3.0-11.0 cm). Multivariate analysis revealed that the following factors were associated with PGS development: diabetes (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.1-21.2; P = .013), smoking (OR, 5.6; 95% CI, 0.73-33.74; P = .01), anticoagulation (OR, 7.2; 95% CI, 2.6-63.3; P = .003), bifurcated graft reconstruction (OR, 8.0; 95% CI, 2.6-94.1; P = .017), and left flank retroperitoneal approach for repair (OR, 7.1; 95% CI, 1.9-26.5; P = .003). Four patients (4 of 20; 20%) required intervention for PGS-related complications: 3 patients for symptomatic PGS expansion (1 patient with rupture) and 1 patient for acute limb ischemia secondary to graft limb compression and thrombosis. Two patients had open exploration, sac evacuation/reduction, and graft replacement with a Dacron graft: 1 patient for a ruptured aneurysm sac and 1 patient for persistent pain associated with sac enlargement. A third patient underwent a failed CT-guided drainage for abdominal pain and was subsequently treated with partial graft excision. The patient with acute limb ischemia was treated with catheter-directed thrombolysis and graft limb stenting. CONCLUSION: PGS after open AAA repair occurs more frequently than previously reported. Complications requiring intervention can occur in up to 20% of patients with PGS. A variety of treatment modalities can be used to deal with the complications. Earlier CT surveillance is advised after open AAA repair with a PTFE graft if symptoms are suggestive of PGS development.

Contemporary presentation and evolution of management of neck paragangliomas.

BACKGROUND: The aim of the present study was to review the contemporary presentation and evolution of management of neck paragangliomas. METHODS: Forty-one neck paragangliomas operated on in 36 patients over a 44 year period were included in the current report. The study period was divided into two parts, the first three decades (1964-1989), during which the current management techniques were evolved, and the last two decades (1990-2008). RESULTS: Patients presented with a palpable neck mass (n = 17), cranial nerve (CN) palsy (n = 3) or both (n = 6), or the lesion was an incidental finding (n = 14). The use of cross-section imaging modalities (n = 24) increased from 35% during the first part of the study to 95% during the second part of the study (P < .001). Preoperative embolization (introduced in 1979) was performed in 60% (median size 4.3 cm for embolized vs 3 cm [P = .02], for non-embolized tumors). During the first study period, the frequency of Shamblin group II/III tumors was 95% compared with a frequency of 42% during the second study period (P < .001, odds ratio 25), median blood loss was 600 ml and 150 ml, respectively (P = .001) and the transfusion rate was 44% and 5%, respectively (P = .008). The incidence of temporary and permanent new CN deficits postoperatively was 22.5% and 10%, respectively, and was similar during the two study periods. Three tumors were malignant, based on lymph node involvement (n = 1) or development of late metastases (n = 2). CONCLUSIONS: In the modern era, neck paragangliomas can be managed with a low incidence of long-term sequelae. Smaller, asymptomatic, and incidentally detected tumors are currently the most common presentation pattern.

Equivalent secondary patency rates of upper extremity Vectra Vascular Access Grafts and transposed brachial-basilic fistulas with aggressive access surveillance and endovascular treatment.

OBJECTIVES: The 2006 update of the DOQI guidelines has stated that in patients with end-stage renal disease, autogenous radial-cephalic, or brachial-cephalic fistulas are the preferred access modalities, followed by transposed brachial-basilic (TBB) fistulas and prosthetic arteriovenous (AV) grafts. AV grafts are in general least preferred; however, there is very limited data comparing directly the last two modalities. The aim of the present study is to compare outcomes of the TBB fistula and the Vectra Vascular Access Graft. METHODS: Seventy-six patients had a prosthetic brachial-axillary Vectra graft placed, while in 41 patients brachial-basilic upper arm transposition was performed. Graft surveillance to detect a failing/failed access was followed by endovascular treatment, rheolytic thrombectomy (AngioJet, Possis Medical), and/or angioplasty +/- stenting of the responsible anatomical lesion(s). RESULTS: Use of Vectra grafts and TBB fistulas started after a median (interquartile range) of 14 (7-30) and 70 (52-102) days, respectively (P < .001), as early as the operative day in some patients with grafts. Postoperative complications were more frequent in TBB fistulas and late complications (mainly access thrombosis) in Vectra grafts. Total number of thrombectomy sessions performed for graft or fistula occlusion was 45 and 7, respectively (P = .032); total number of isolated angioplasty sessions, performed for failing graft or fistula was 31 and 45, respectively (P = .004). Although primary patency of the two access modalities was equivalent, primary assisted patency was significantly reduced in Vectra grafts (70% at 12 months and 58% at 18 months), compared with TBB fistulas (82% at 12 months and 78% at 18 months, P = .033); however, as a result of endovascular intervention, secondary patency rates at 12 months (87% vs 88%) and 18 months (87% vs 83%) were equivalent (P = .91). Presence of arterial anastomosis stenosis treated with angioplasty at any stage had a significant negative predictive value on secondary patency rates at 12 and 18 months which were 61%, compared with 96% for Vectra grafts that had any intra-graft, venous outflow, draining or central vein stenosis treated with angioplasty at any stage (P = .010). CONCLUSIONS: Aggressive graft surveillance and endovascular treatment methods can yield equivalent long-term secondary patency rates between Vectra graft and TBB fistulas. The advantage of earlier use of Vectra graft must be balanced against the need for more frequent secondary interventions and the risk of graft infection.