Heparin-induced Thrombocytopenia (HIT) in the DOAC Era.

OBJECTIVES: Heparin-induced thrombocytopenia (HIT) is an uncommon complication of heparin therapy with significant risk for severe morbidity and mortality. We investigated the role and outcome of direct oral anticoagulants (DOACs) for the management of HIT. METHODS: After IRB approval, a retrospective review was performed identifying all patients with positive HIT serotonin-release assays between 2020 and 2022 at two hospitals. Demographic and clinical variables were collected: initial anticoagulant, dosing and indication, interval before onset of HIT, thrombotic complications, platelet nadir and recovery, direct thrombin inhibitor (DTI) and DOAC usage, and clinical outcomes. RESULTS: 15 patients were included in the study. 8 underwent a vascular procedure, 3 had cardiac surgery, 1 patient had both and was included in both groups, and 5 patients had either non-cardiac, non-vascular surgery or no surgery. 14 patients received unfractionated heparin (93% with therapeutic dosing) and 1 received prophylactic enoxaparin prior to diagnosis of HIT. The average time to diagnosis of HIT was 10.77 days after initial anticoagulation. In-hospital mortality was 27%, related to Covid-19 infection (3/4) and intracranial hemorrhage (1/4). 40% developed thrombosis (67% venous, 33% arterial) after the diagnosis of HIT. 8/11 survivors were discharged on a DOAC. With DOAC therapy, platelet counts rebounded to an average of 265K (+/- 104.6K) within an average of 2.3 days and 364K (+/- 273.9K) within 30 days after initiation of a DOAC. No recurrent thrombosis occurred after DOAC administration and only one patient had persistent thrombocytopenia within 30 days. CONCLUSIONS: Mortality and thrombosis (arterial and venous) are common complications in patients diagnosed with HIT. In patients who survive to discharge, DOACs are the most common discharge antithrombotic agent, with low rates of recurrent thrombosis and thrombocytopenia.

Peak systolic velocity and color aliasing are important in the development of duplex ultrasound criteria for external carotid artery stenosis.

OBJECTIVE: The external carotid artery (ECA) serves as a major collateral pathway for ophthalmic and cerebral artery blood supply. It is routinely examined as part of carotid duplex ultrasound, but criteria for determining ECA stenosis are poorly characterized and typically extrapolated from internal carotid artery data. This is despite the fact that the ECA is smaller in diameter, with a higher resistance and lower volume flow pattern. We hypothesized that using the cutoff of a peak systolic velocity (PSV) ≥125 cm/s, extrapolated from internal carotid artery data, will overestimate the prevalence of ≥50% ECA stenosis and aimed to determine a more appropriate criterion. METHODS: From December 2016 to July 2017, consecutive carotid duplex ultrasound studies performed in our university hospital Intersocietal Accreditation Commission-accredited vascular laboratory were prospectively identified and categorized with respect to prevalence and distribution of ECA PSVs and color aliasing, an indication of turbulent flow or flow acceleration. Presence of color aliasing was determined by two individual reviewers and agreement assessed by Cohen κ coefficient. ECA stenosis was calculated by the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method in patients with computed tomography angiography (CTA) performed within 3 months of carotid duplex ultrasound without an intervening intervention. Receiver operating characteristic analysis was performed to identify best criteria for determining ≥50% ECA stenosis. RESULTS: There were 1324 ECAs from 662 patients analyzed; 174 patients had a total of 252 ECAs with PSV ≥125 cm/s (19% of the total sample). Of those ECAs with PSVs ≥125 cm/s, 30.5% were between 125 and 149 cm/s, 22.2% were between 150 and 174 cm/s, 13.1% were between 175 and 199 cm/s, and 34.1% were ≥200 cm/s. There were 341 ECAs that were analyzed for the presence of color aliasing. In 86 ECAs with PSV ≥200 cm/s, 58.1% had color aliasing, whereas in 255 ECAs with PSV <200 cm/s, only 19.2% had color aliasing (P = .0001). There were 325 CTA studies reviewed and assessed for the presence of a ≥50% ECA stenosis as determined by CTA. Overall, the combination of an ECA PSV ≥200 cm/s with the presence of color aliasing provided the highest combination of sensitivity (90%), specificity (96%), positive predictive value (83%), and negative predictive value (98%) and the greatest area under the curve of 0.971 for determining the presence of a ≥50% ECA stenosis based on CTA. CONCLUSIONS: A PSV ≥125 cm/s alone probably overestimates the prevalence of ≥50% ECA stenosis. A PSV ≥200 cm/s combined with color aliasing is highly predictive of >50% ECA stenosis based on correlation with CTA.

Experienced operators achieve superior patency and wound complication rates with endoscopic great saphenous vein harvest compared with open harvest in lower extremity bypasses.

OBJECTIVE: Prior studies have suggested improved wound complication rates but decreased primary patency in lower extremity bypasses performed with endoscopic vein harvest (EVH) vs open vein harvest (OVH). We hypothesize that the inferior patency reflects the initial learning curve for EVH and that improved patency can be achieved with experience. METHODS: This was a single-institution review of 113 patients with critical limb ischemia who underwent infrainguinal bypass with a continuous segment of great saphenous vein harvested endoscopically (n = 49) or through a single open incision (n = 64) from 2012 to 2017. EVH was performed by surgeons with >5 years' experience with this technique. Operative outcomes, patency, complications, and readmission rates were compared between the harvest methods. EVH data were also compared with our prior reported series of our initial experience with this technique to determine the effects of experience on outcomes. RESULTS: There were no significant differences in patient demographics, medications, operative indications, or inflow/outflow vessels between the two groups. Mean operative time was 322 minutes and median hospital length of stay was 6 days for OVH, and was 340 minutes and 5 days for EVH, which was not significant. Harvest-related wound complications were more frequent with OVH (28% vs 2%, P < .001). Primary patency at 1 and 3 years was 65% and 58% for OVH, and 79% and 71% for EVH, respectively (P = .18), assisted primary patency was 77% and 74% for OVH and 94% and 89% for EVH, respectively (P = .05), and secondary patency was 82% and 79% for OVH and 95% and 95% for EVH, respectively (P = .03). The 30-day readmission rates were similar between OVH (20%) and EVH (12%, P = .26), but 90-day readmissions were more frequent in the OVH group (34% vs 14%, P = .018). Compared with our earlier series of EVH, the current cohort had significantly improved 3-year primary (71% vs 42%, P = .012), primary assisted patency (89 vs 66%, P = .034), and secondary patency (95% vs 66%, P = .003). CONCLUSIONS: With experience, lower extremity bypass using EVH can result in improved patency compared with OVH and initial EVH use, while also resulting in fewer wound complications and readmissions, with comparable operative times and hospital length of stay. This technique should be more widely adopted by vascular surgeons as a primary method of vein harvest.

The efficacy and safety of a catheter removal only strategy for the treatment of PICC line thrombosis versus standard of care anticoagulation: a retrospective review.

Peripherally-inserted central catheters (PICCs) are commonly used during hospitalization. Unfortunately, their use can be complicated by catheter-related thrombosis (CRT). Current guidelines recommend 3-6 months of anticoagulation for patients with CRT after catheter removal. This recommendation is based on extrapolation of data on lower extremity thrombosis, as data is lacking regarding the efficacy and safety of more specific management strategies. Many providers feel catheter removal alone is a reasonable treatment option, particularly for patients at risk for bleeding. We performed a retrospective analysis of hospitalized adult patients diagnosed with CRT at our center. We determined rates of progressive thrombosis and bleeding in cohorts of patients who underwent catheter removal vs those who had catheters removed and received anticoagulation. Among 83 total patients, 62 were treated with PICC removal alone, while 21 underwent PICC removal followed by therapeutic anticoagulation. Patients treated with PICC removal alone were more likely to have hematologic malignancy, receive chemotherapy, develop thrombocytopenia, and have brachial vein thrombosis. No patients in the PICC removal plus anticoagulation arm developed progressive thrombosis, while 6.4% of patients treated with catheter removal alone developed a secondary VTE event, including one PE, three DVTs, and five patients (8%) who developed progressive symptoms leading to initiation of anticoagulation. Major bleeding was significantly more common in the PICC removal + anticoagulation arm (28.5% vs. 4.8% p = 0.007). Catheter-removal alone results in significantly reduced major bleeding compared with catheter-removal plus anticoagulation. In select patients, catheter removal alone may be an option for CRT.

Interhospital vascular surgery transfers to a tertiary care hospital.

OBJECTIVE: Interhospital transfers (IHTs) to tertiary care centers are linked to lower operative mortality in vascular surgery patients. However, IHT incurs great health care costs, and some transfers may be unnecessary or futile. In this study, we characterize the patterns of IHT at a tertiary care center to examine appropriateness of transfer for vascular surgery care. METHODS: A retrospective review was performed of all IHT requests made to our institution from July 2014 to October 2015. Interhospital physician communication and reasons for not accepting transfers were reviewed. Diagnosis, intervention, referring hospital size, and mortality were examined. Follow-up for all patients was reviewed. RESULTS: We reviewed 235 IHT requests for vascular surgical care involving 210 patients during 15 months; 33% of requested transfers did not occur, most commonly after communication with the physician resulting in reassurance (35%), clinic referral (30%), or further local workup obviating need for transfer (11%); 67% of requests were accepted. Accepted transfers generally carried life- or limb-threatening diagnoses (70%). Next most common transfer reasons were infection or nonhealing wounds (7%) and nonurgent postoperative complications (7%). Of accepted transfers, 72% resulted in operative or endovascular intervention; 20% were performed <8 hours of arrival, 12% <24 hours of arrival, and 68% during hospital admission (average of 3 days); 28% of accepted patients received no intervention. Small hospitals (<100 beds) were more likely than large hospitals (>300 beds) to transfer patients not requiring intervention (47% vs 18%; P = .005) and for infection or nonhealing wounds (30% vs 10%; P = .013). Based on referring hospital size, there was no difference in IHTs requiring emergent, urgent, or nonurgent operations. There was also no difference in transport time, time from consultation to arrival, or death of patients according to hospital size. Overall patient mortality was 12%. CONCLUSIONS: Expectedly, most vascular surgery IHTs are for life- or limb-threatening diagnoses, and most of these patients receive an operation. Transfer efficiency and surgical case urgency are similar across hospital sizes. Nonoperative IHTs are sent more often by small hospitals and may represent a resource disparity that would benefit from regionalizing nonurgent vascular care.

Ambulation and functional outcome after major lower extremity amputation.

OBJECTIVE: Major lower extremity amputations (MLEAs) remain a significant source of disability. It is unknown whether postamputation functional outcomes and outcome predictability have changed with a population of increasingly aging and obese patients. Accordingly, we sought to evaluate contemporary trends. METHODS: A retrospective chart review was performed to identify patients undergoing MLEA using Current Procedural Terminology codes in a university hospital. Demographics, comorbidities, perioperative variables, and outcomes were obtained. Descriptive statistics, t-tests, and χ2 and multivariate logistic regression modeling were used where appropriate. Survival analyses were performed with the Kaplan-Meier method. RESULTS: From October 2005 to November 2016, 206 patients (147 male; mean age, 63 ± 13.5 years) underwent 256 MLEAs (90.9% below-knee amputations, 1.3% through-knee amputations, and 7.8% above-knee amputations [AKAs]) related to acute and critical limb ischemia, infection, or other causes. Mean follow-up was 178.7 ± 266.9 days. Conversion from below-knee amputation to AKA was 3.5%. Estimated 1-year survival was 83%, and it was 15% lower in nonambulatory patients (75% vs 90%; P = .04). Overall 1-year postamputation ambulatory rate was 46.1%. Nonambulatory patients had a higher body mass index (30.9 ± 8.0 vs 25.6 ± 5.4; P < .001), lower preoperative hematocrit (31.0% ± 7.4% vs 33.3% ± 8.1%; P < .05), higher modified frailty index (mFI; 8.4 ± 1.0 vs 5.4 ± 1.2; P < .0001), higher chronic alcohol use (9% vs 1%; P = .01), dependent preoperative functional status (29% vs 2.1%; P < .01), and lack of family support (66.3% vs 17.9%; P < .01); they were less likely to be married (83.2% vs 35.8%; P < .01) and more likely to have an AKA (20% vs 52.6%; P = .004). There were no patients with dementia, on dialysis, or with bilateral MLEAs who were ambulatory after amputation. Factors predictive of nonambulatory status after MLEA with multivariate logistic regression analysis included increased body mass index (odds ratio [OR], 0.88; 95% confidence interval [CI], 0.81-0.98; P = .017) and an increased mFI (OR, 0.23; 95% CI, 0.16-0.34; P < .0001); a higher hemoglobin level was protective (OR, 1.3; 95% CI, 1.03-1.62; P = .019). CONCLUSIONS: Patients should be counseled that <50% of patients receiving MLEAs are ambulatory after amputation. Educating patients about the deleterious effects of obesity on ambulatory status after MLEA may motivate patients to improve their level of fitness to achieve successful ambulation. Patients with an elevated mFI, patients with dementia, and those on dialysis should be considered for AKAs.

Causes and outcomes of finger ischemia in hospitalized patients in the intensive care unit.

OBJECTIVE: Vascular surgeons may be consulted to evaluate hospitalized patients with finger ischemia. We sought to characterize causes and outcomes of finger ischemia in intensive care unit (ICU) patients. METHODS: All ICU patients who underwent evaluation for finger ischemia from 2008 to 2015 were reviewed. All were evaluated with finger photoplethysmography. The patients' demographics, comorbidities, ICU care (ventilator status, arterial lines, use of vasoactive medications), finger amputations, and survival were also recorded. ICU patients were compared with concurrently evaluated non-ICU inpatients with finger ischemia. RESULTS: There were 98 ICU patients (55 male, 43 female) identified. The mean age was 57.1 ± 16.8 years. Of these patients, 42 (43%) were in the surgical ICU and 56 (57%) in the medical ICU. Seventy (72%) had abnormal findings on finger photoplethysmography, 40 (69%) unilateral and 30 (31%) bilateral. Thirty-six (37%) had ischemia associated with an arterial line. Twelve (13%) had concomitant toe ischemia. Eighty (82%) were receiving vasoactive medications at the time of diagnosis, with the most frequent being phenylephrine (55%), norepinephrine (47%), ephedrine (31%), epinephrine (26%), and vasopressin (24%). Treatment was with anticoagulation in 88 (90%; therapeutic, 48%; prophylactic, 42%) and antiplatelet agents in 59 (60%; aspirin, 51%; clopidogrel, 15%). Other frequently associated conditions included mechanical ventilation at time of diagnosis (37%), diabetes (34%), peripheral arterial disease (32%), dialysis dependence (31%), cancer (24%), and sepsis (20%). Only five patients (5%) ultimately required finger amputation. The 30-day, 1-year, and 3-year survival was 84%, 69%, and 59%. By Cox proportional hazards modeling, cancer (hazard ratio, 2.4; 95% confidence interval, 1.1-5.6; P = .035) was an independent predictor of mortality. There were 50 concurrent non-ICU patients with finger ischemia. Non-ICU patients were more likely to have connective tissue disorders (26% vs 13%; P = .05) and hyperlipidemia (42% vs 24%; P = .03) and to undergo finger amputations (16% vs 5%; P = .03). CONCLUSIONS: Finger ischemia in the ICU is frequently associated with the presence of arterial lines and the use of vasopressor medications, of which phenylephrine and norepinephrine are most frequent. Anticoagulation or antiplatelet therapy is appropriate treatment. Whereas progression to amputation is rare, patients with finger ischemia in the ICU have a high rate of mortality, particularly in the presence of cancer. Non-ICU patients hospitalized with finger ischemia more frequently require finger amputations, probably because of more frequent connective tissue disorders.

Demographic and echocardiographic predictors of anatomic site and outcomes of surgical interventions for cardiogenic limb emboli.

We sought to determine if symptomatic cardiogenic limb emboli have a random distribution or if there are demographic or echocardiographic factors that predict site of embolization, limb salvage and mortality. Upper (UE) and lower extremity (LE) emboli were evaluated over a 16-year period (1996-2012). Demographic (age, gender, smoking, medical comorbidities) and echocardiographic data were analyzed to determine predictors of embolic site. All symptomatic patients underwent surgical revascularization. Limb salvage and mortality were compared with Kaplan-Meier analysis. A total of 161 patients with symptomatic cardiogenic emboli were identified: 56 UE and 105 LE. The female-to-male ratio for UE emboli (70%:30%) was significantly higher than for LE emboli (47%:53%, p=0.008). No other demographic factors were statistically different. Upper extremity patients were more likely to have atrial fibrillation (50% vs 29.8%, p=0.028), while LE patients had a higher percentage of aortic or mitral valvular disease or intracardiac thrombus (71.4% vs 52.5%, p=0.038). The 30-day limb salvage was higher for UE compared to LE (100% vs 88%, p=0.008). There was a trend toward higher 30-day mortality in the LE group (14% vs 5%, p=0.11). Survival at 1, 3, and 5 years were similar (UE: 62.2%, 44.2%, 35.3%; LE: 69.1%, 47.5%, 30.3%; p=ns). Upper extremity emboli are more frequent in women and patients with atrial fibrillation. Lower extremity emboli are more frequent in the presence of valvular disease or intracardiac thrombus, and are associated with increased 30-day limb loss and mortality. These findings suggest gender- and cardiac-specific differences in patterns of blood flow leading to preferential sites of peripheral embolization.

Incidence and outcomes of intraoperative vascular surgery consultations.

OBJECTIVE: Vascular surgeons may aid in primarily nonvascular procedures. Such activity has not been quantified, and hospital administrators may be unaware of the importance of vascular surgeons to support other hospital-based surgical programs. This study reviewed intraoperative consultations by vascular surgeons to support other surgical services. METHODS: Intraoperative vascular consultations were reviewed from January 2006 to January 2014 for consulting service, indication, and whether consultation occurred with advanced notice. Patient demographics, operative times, estimated blood loss, length of stay, and relative value units (RVUs) assigned for each consultation were also assessed. Consultations for trauma and iatrogenic injuries occurring outside the operating theater were excluded. RESULTS: Vascular surgeons performed 225 intraoperative consultations in support of procedures by nonvascular surgeons. Requesting services were surgical oncology (46%), orthopedics (17%), urology (11%), otolaryngology (7%), and others (19%). Reasons for consultation overlapped and included vascular reconstruction (53%), control of hemorrhage (39%), and assistance with difficult dissections (43%). Seventy-four percent were for intra-abdominal procedures, and venous (53%) and arterial (50%) problems were encountered equally with some overlap. Most patients were male (59%), overweight (56%; body mass index ≥25 kg/m(2)), had previous surgery (72%) and were undergoing elective procedures (89%). Mean total procedural anesthesia time was 9.4 hours, mean procedural operating time was 7.9 hours, and mean total and vascular-related estimated blood loss was 1702 mL and 327 mL, respectively. Mean length of stay was 14.7 days, mean intensive care unit stay was 2.9 days, and 30-day mortality was 6.2%. Mean nonvascular RVUs per operation were 46.0, and mean vascular RVUs per operation were 30.9. CONCLUSIONS: Unexpected intraoperative need for vascular surgical expertise occurs often enough that vascular surgeons should be regarded as an essential operating room resource to the general operating room, nonvascular surgeons, and their patients. Intraoperative vascular surgical consultation in support of other surgeons requires a high level of open technical operative skills and is time and labor intensive.

Nasal methicillin-resistant Staphylococcus aureus colonization is associated with increased wound occurrence after major lower extremity amputation.

OBJECTIVE: Wound occurrence (WO) after major lower extremity amputation (MLEA) can be due to wound infection or sterile dehiscence. We sought to determine the association of nasal methicillin-resistant Staphylococcus aureus (MRSA) colonization and other patient factors with overall WO, WO due to wound infection, and WO due to sterile dehiscence. METHODS: The medical records of all patients undergoing MLEA from August 1, 2011, to November 1, 2013, were reviewed. Demographic data, hemoglobin A1c level, albumin concentration, dialysis dependence, peripheral vascular disease (PVD), nasal MRSA colonization, and diabetes mellitus (DM) were examined as variables. The overall WO rate was determined, and the cause of WO was categorized as either a sterile dehiscence or a wound infection. RESULTS: Eighty-three patients underwent 96 MLEAs during a 27-month period. The rates of overall WO, WO due to infection, and WO due to sterile dehiscence were 39%, 19%, and 19%, respectively (1% developed a traumatic wound). On univariate analysis, PVD, MRSA colonization, DM, and dialysis dependence were all associated with higher rates of overall WO (P < .05). On multivariate analysis, MRSA colonization was associated with higher rates of overall WO (P = .03) and WO due to wound infection (11% vs 45%; P < .01). DM and PVD were associated with higher rates of overall WO and WO due to sterile dehiscence on both univariate and multivariate analysis (P < .05). CONCLUSIONS: Nasal MRSA colonization is associated with higher rates of overall WO and WO due to wound infection. DM and PVD are associated with higher rates of overall WO and WO due to sterile dehiscence but are not associated with WO due to wound infection. Further studies addressing the effect of nasal MRSA eradication on postoperative wound outcomes after MLEA are warranted.

Objective measurement of lower extremity function and quality of life after surgical revascularization for critical lower extremity ischemia.

BACKGROUND: Outcomes of revascularization for critical limb ischemia (CLI) have historically been patency, limb salvage, and survival. Functional status and quality of life have not been well described. This study used functional and quality of life assessments to measure patient-centered outcomes after revascularization for CLI. METHODS: The study observed 18 patients (age, 65 ± 11 years) prospectively before and after lower extremity bypass for CLI. Patients completed the Short Physical Performance Battery, which measures walking speed, leg strength, and balance, as well as performed a 6-minute walk, and calorie expenditure was measured by an accelerometer. Isometric muscle strength was assessed with the Muscle Function Evaluation chair (Metitur, Helsinki, Finland). Quality of life instruments included the 36-Item Short Form Health Survey and the Vascular Quality of Life questionnaire. Patients' preoperative status was compared with 4-month postoperative status. RESULTS: Muscle Function Evaluation chair measurements of ipsilateral leg strength demonstrated a significant increase in knee flexion from 64 ± 62 N to 135 ± 133 N (P = .038) and nearly significant increase in knee extension from 120 ± 110 N to 186 ± 85 N (P = .062) and ankle plantar flexion from 178 ± 126 N to 267 ± 252 N (P = .078). In the contralateral leg, knee flexion increased from 71 ± 96 N to 149 ± 162 N (P = .028) and knee extension from 162 ± 112 N to 239 ± 158 N (P = .036). Absolute improvements were noted in 6-minute walk distance, daily calorie expenditure, and individual domains and overall Short Physical Performance Battery scores, and upper extremity strength decreased, although none were significant. The Vascular Quality of Life questionnaire captured significant improvement in all individual domains and overall score (P < .015). Significant improvement was noted only for bodily pain (P = .011) on the 36-Item Short Form Health Survey. CONCLUSIONS: Despite lack of statistical improvement in most functional test results, revascularization for CLI results in improved patient-perceived leg function. Significant improvements in isometric muscle strength may explain the measured improvement in quality of life after revascularization for CLI.

Open versus endoscopic great saphenous vein harvest for lower extremity revascularization of critical limb ischemia.

OBJECTIVE: This study determined wound complication rates, intervention rates, failure mechanisms, patency, limb salvage, and overall survival after lower extremity revascularization using open vein harvest (OVH) vs endoscopic vein harvest (EVH) for critical limb ischemia. METHODS: A single-institution review was conducted of consecutive patients who underwent infrainguinal bypass with a single-segment reversed great saphenous vein between 2005 and 2012. RESULTS: A total of 251 patients with critical limb ischemia underwent revascularization, comprising 153 with OVH and 98 with EVH. The OVH group had a lower mean body mass index (26.7 vs 29.9 kg/m(2); P = .001). There were no other differences in demographics, comorbidities, medications, smoking, or in the proximal or distal anastomotic site. Median operative times were 249 minutes (OVH) vs 316 minutes (EVH; P < .001). Median postoperative hospital length of stay was 7 days (OVH) vs 5 days (EVH; P < .001). Median follow-up was 295 days (OVH) vs 313 days (EVH; P = .416). During follow-up, 21 OVH grafts (14%) and 27 EVH grafts (28%) underwent an intervention (P = .048). There were a similar number of surgical interventions: 50% (OVH) vs 61% (EVH; P = .449). Failed grafts had a mean of 1.2 stenoses per graft, regardless of harvest method. Median stenosis length was 2.1 cm (OVH) vs 2.5 cm (EVH; P = .402). At 1 and 3 years, the primary patency was 71% and 52% (OVH) vs 58% and 41% (EVH; P = .010), and secondary patency was 88% and 71% (OVH) vs 88% and 64% (EVH; P = .266). A secondary patency Cox proportional hazard model showed EVH had a hazard ratio of 2.93 (95% confidence interval, 1.03-8.33; P = .044). Overall and harvest-related wound complications were 44% and 29% (OVH) vs 37% and 12% (EVH; P = .226 and P = .002). At 5 years, amputation-free survival was 48% (OVH) vs 54% (EVH; P = .305), and limb salvage was 89% (OVH) and 91% (EVH; P = .615). CONCLUSIONS: OVH and EVH have similar failure mechanisms, limb salvage, amputation-free survival, and overall survival. EVH is associated with impaired patency, increased need for intervention, longer operative times, shorter hospital stays, and decreased vein harvest site wound complications. OVH of the great saphenous vein may provide optimal patency but was not necessarily associated with better patient-centered outcomes. Similar limb salvage rates and amputation-free survival may justify the use of EVH, despite inferior patency, to capture shorter hospital stays and decreased wound complications.

Utility of direct angiosome revascularization and runoff scores in predicting outcomes in patients undergoing revascularization for critical limb ischemia.

OBJECTIVE: Both runoff scores and direct (DR) vs indirect revascularization (IR) according to pedal angiosomes have unclear impact on outcome for patients with critical limb ischemia (CLI). We compared DR vs IR and runoff scores in CLI patients undergoing infrapopliteal bypass for foot wounds. METHODS: Patients who had tibial/pedal bypass for a foot/ankle wound from 2005-2011 were identified and operations classified as DR or IR based on wound location and bypass target. A blinded observer reviewed angiograms for an intact pedal arch and calculated standard Society for Vascular Surgery (single tibial) and modified (composite tibial) runoff scores. Comorbidities, wound characteristics, wound healing, major amputation, and overall survival were determined. RESULTS: A total of 106 limbs were revascularized in 97 patients; 54 limbs had DR and 52 had IR, although only 36% of wounds corresponded to a single, distinct angiosome. Wound characteristics and comorbidities were similar between groups. Mean standard (7.9 vs 7.2; P = .001) and modified (22.2 vs 20.0; P = .02) runoff scores were worse (higher number indicates worse runoff) in the IR vs DR groups; 33% had a complete pedal arch. Complete wound healing (78% vs 46%; P = .001) and time to complete healing (99 vs 195 days; P = .002) were superior with DR vs IR but were not influenced by runoff score, modified runoff score or presence of complete plantar arch. In multivariate models controlling for runoff score, DR remained a significant predictor for wound healing (odds ratio, 2.9; 95% confidence interval, 1.1-7.4; P = .028) and reduced healing time (hazard ratio, 2.1; 95% confidence interval, 1.2-3.7; P = .012). Mean amputation-free survival (75 vs 71 months for DR vs IR; P = .82) and median survival (36 vs 33 months DR vs IR; P = .22) were not different for DR vs IR. CONCLUSIONS: DR according to pedal angiosomes provides more efficient wound healing, but is possible in only one-half of the patients and does not affect amputation-free or overall survival. DR is associated with improved runoff scores, but current runoff scores have little clinical utility in predicting outcomes in CLI patients.

Lower extremity autologous vein bypass for critical limb ischemia is not adversely affected by prior endovascular procedure.

OBJECTIVE: It has been reported that a failed endovascular intervention adversely affects results of lower extremity bypass (LEB). We reviewed rates of prior endovascular intervention (PEI) in patients undergoing LEB with autologous vein for critical limb ischemia (CLI) to determine effects on graft patency, limb salvage, and amputation-free survival. METHODS: Retrospective review was conducted of consecutive autologous vein LEBs performed for CLI between 2005 and 2012 at a tertiary care academic medical center. RESULTS: Overall, 314 autologous vein LEBs were performed for CLI, 71% for tissue loss. TransAtlantic Inter-Society Consensus II type D or type C lesions were present in 62% and 25%, respectively. The great saphenous vein was used as a conduit in 83%, and the distal target was infrapopliteal in 60%. The 30-day mortality rate was 3.5%. Primary patency rates at 1 year and 5 years were 61% and 45%. Secondary patency rates at 1 year and 5 years were 88% and 64%, with 23% requiring an intervention to maintain patency. The 5-year limb salvage rate was 89%, and the 5-year amputation-free survival was 49%. There were 61 patients (19%) who had undergone a PEI and 253 (81%) who underwent bypass with no prior endovascular intervention (NPEI). There were 19 iliac stents, 29 femoral interventions, 13 popliteal interventions, 9 crural interventions, 9 infrainguinal thrombectomies, and 13 infrainguinal thrombolyses. PEI and NPEI patients had similar demographics and prevalence of atherosclerotic risk factors. The 1-year primary patency rate was 62% for NPEI patients vs 59% for PEI patients (P = .759). The 1-year and 2-year secondary patency rates were 87% and 79% for NPEI patients vs 89% and 78% for PEI patients (P = .947). The 3-year limb salvage rate was 89% for NPEI patients vs 92% for PEI patients (P = .445). The 3-year amputation-free survival was 59% for NPEI patients vs 52% for PEI patients (P = .399). Median follow-up time was 323 days for NPEI patients (interquartile range, 83-918) vs 463 days for PEI patients (interquartile range, 145-946; P = .275). CONCLUSIONS: Overall operative mortality, patency rates, and limb salvage for autologous vein LEB in CLI patients continue to be excellent in the endovascular era and are not necessarily affected by a prior ipsilateral endovascular procedure. Long-term survival remains poor in CLI patients requiring LEB.

A modern series of acute aortic occlusion.

OBJECTIVE: Acute aortic occlusion (AAO) is a rare condition associated with substantial morbidity and mortality. The most recent large series was published over 15 years ago and included patients from the 1980s. Previous studies reported up to 50% of AAOs are caused by embolization, with a mortality rate approaching 50%. We reviewed our recent experience with AAOs to identify current etiologies and outcomes in a contemporary series of patients with AAOs. METHODS: Current Procedural Terminology codes and data from a prospectively maintained vascular surgical database were used to identify patients with acute occlusion of the native aorta between 2005 and July 2013. AAOs secondary to trauma, dissection, or graft occlusion were excluded. RESULTS: We identified 29 patients with AAOs treated at our institution. Twenty-three patients were transferred from referring hospitals with a mean transfer time of 3.9 hours (range, 0.5-7.5 hours). Twenty-two presented with occlusion below the renal arteries and seven with occlusion extending above the renal arteries. Resting motor/sensory lower extremity deficits were noted in 17 patients. Eight patients presented with complete paraplegia. Etiology was felt to be aortoiliac thrombosis in 22 cases, embolic occlusion in 2, and indeterminate in 5. Surgical revascularization was performed in 26 cases (extra-anatomic bypass in 18, thromboembolectomy in 5, and aortobifemoral bypass in 3 patients. Three patients had no intervention. Acute renal failure developed in 15 patients and rhabomyolysis in 10 patients. Fasciotomy was performed in 19 extremities. Nine extremities were amputated in six patients. Overall mortality was 34% with a 30-day mortality of 24% and a postprocedure mortality of 15%. CONCLUSIONS: AAO is an infrequent but devastating event. The dominant etiology of AAOs is now thrombotic occlusion. Despite advances in vascular surgery and critical care over the past 2 decades, associated morbidity and mortality remain substantial with high rates of limb loss, acute renal failure, rhabdomyolysis, and death. Mortality may be improved with expeditious extra-anatomic bypass.

Paroxysmal nocturnal hemoglobinuria: a red clot syndrome.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired, nonmalignant disorder of hematopoietic stem cells characterized by hemolysis, diminished hematopoiesis, and thrombophilia. We describe a 65-year-old woman with known PNH and peripheral arterial disease who presented with critical limb ischemia and a nonhealing left foot ulcer. She underwent surgical bypass of a diffusely diseased left superficial femoral artery with autologous reversed saphenous vein graft. Her postoperative course was complicated by wound sepsis and PNH exacerbation with resultant graft thrombosis requiring an above-knee amputation. This case highlights several key concepts relevant to the management of vascular surgery patients with PNH: (1) their predisposition for arterial and venous thrombosis; (2) hypercoagulability despite standard anticoagulation regimens; (3) the role of eculizumab (a monoclonal antibody that inhibits complement activation used to treat PNH) in reducing thrombotic complications and hemolysis; and (4) complications associated with the immunosuppressive effects of eculizumab. We recommend careful monitoring of hemolysis and immunosuppression, aggressive anticoagulation, frequent graft surveillance, and early consultation with hematology.

Compliance with long-term surveillance recommendations following endovascular aneurysm repair or type B aortic dissection.

OBJECTIVE: Lifelong surveillance is recommended for both endovascular aneurysm repair and acute, uncomplicated type B thoracic aortic dissection, though compliance remains a significant challenge. We sought to determine factors associated with failure to obtain recommended surveillance. METHODS: Patients surviving to discharge who had endovascular repair of thoracic (thoracic endovascular aortic aneurysm repair [TEVAR]) or abdominal aortic aneurysms (endovascular aortic aneurysm repair [EVAR]) or medical management for type B dissections from 2004-2011 were reviewed. Primary end points were compliance with follow-up and need for reintervention. Comorbidities examined included coronary artery disease, congestive heart failure, hypertension, chronic obstructive pulmonary disease, diabetes, and chronic kidney disease. Socioeconomic factors examined were age, sex, distance from hospital, discharge destination (ie, home or skilled nursing facility), and insurance type. Endoleak and sac expansion were recorded, as were complications, including endograft migration, infection or thrombosis, and aneurysm degeneration. RESULTS: Two hundred four patients, median age 71.9 years, were identified; 171 had EVAR and 33 had type B dissection. EVAR patients included 45 thoracic, 100 abdominal, and 12 thoracoabdominal endografts, as well as 7 iliac artery aneurysm repairs and 7 proximal/distal graft extensions. Median follow-up was 28 ± 10.5 months. Overall, 56% were lost to follow-up, whereas 11% never returned for surveillance after initial hospitalization. Follow-up was compared for each of the comorbidities and socioeconomic factors; none were found to significantly affect follow-up. The known complication rate was 9.3% (n = 19), with reintervention performed in 14% of EVAR/TEVAR patients. Thirty-eight percent of medically managed patients with type B dissections eventually required surgical intervention. All-cause 5-year mortality was 27% as determined by the Social Security Death Index. CONCLUSIONS: Despite a significant rate of reintervention following EVAR, TEVAR, and type B dissection, long-term compliance with surveillance is limited. In addition, predicting who is at risk of being lost to follow-up remains difficult. If current recommendations for lifelong surveillance are to be followed, coordinated protocols are required to capture EVAR, TEVAR, and type B dissection patients to ensure optimal follow-up for these patients. However, the lack of survival benefit in those with complete follow-up suggests that further study is needed with regard to ideal duration of long-term follow-up.

Medical comorbidities but not interventions adversely affect survival in patients with intermittent claudication.

OBJECTIVE: Intermittent claudication (IC) is common and associated with decreased survival. While patients with IC infrequently progress to critical limb ischemia (CLI), many elect to pursue intervention initially or during follow-up. However, controversy exists as to whether intervention in patients with IC adversely impacts survival or limb salvage. The purpose of this study was to characterize patient demographics and comorbidities with respect to differences in survival and limb salvage among patients who elect no intervention (NI) vs those electing immediate intervention (II) or delayed intervention (DI) for IC. METHODS: Patients referred to a university practice for limb ischemia were identified via a query of the electronic medical record from 2007 to 2011. Patients with prior lower extremity interventions or CLI were excluded. IC patients were classified according to intervention: NI during follow-up, II, and DI. Patient demographics, Charlson morbidity index, survival, and reintervention rates were analyzed. RESULTS: A total of 262 of 1320 patients met inclusion criteria. Thirty patients with possible IC were believed to have nonarterial related symptoms. Study patients included 132 with NI, 62 with II, and 38 with DI. DI patients were younger and less frequently diabetic (median age, 65.5 years, 63.5 years, 58.0 years; P = .002; diabetes, 43.2%, 39.5%, 22.6%; P = .02 for NI, II, and DI, respectively). NI patients had higher Charlson comorbidity scores (P < .05). Hypertension, hyperlipidemia, and diabetes were associated with decreased survival in all groups (P < .05). Median survival was greatest for DI patients and least for NI patients (NI 92 months, II 95 months, DI 143 months; log-rank = .015). Primary patency of interventions at 1 and 5 years were equal for II and DI patients (1 year, II 80% vs DI 79%; 5 years, II 45% vs DI 50%; P = .9). Reintervention was common with rates similar between the II and DI groups (P > .05). Four of 38 DI patients required minor amputation for progression to CLI. There were no major amputations in any group. CONCLUSIONS: Progression to CLI is uncommon in IC. Survival of claudicants is decreased by diabetes, hypertension, and hyperlipidemia but not by intervention for IC. Reintervention is common in treated IC patients but no different among those undergoing II and DI. Intervention did not lead to major amputation. II or DI in IC patients does not affect survival or major amputation.

Factors affecting career choice among the next generation of academic vascular surgeons.

OBJECTIVE: Few studies have examined factors that influence an individual's decision to enter an academic medical career after residency training. We sought to evaluate whether sex, ethnicity, child care issues, and debt burden influenced residents' choice for a career in academic vascular surgery. METHODS: A 39-item Web survey, designed to elucidate which factors motivated residents to seek a career in academic vascular surgery, was sent to 295 vascular surgery residents currently enrolled in Accreditation Council on Graduate Medical Education-accredited training programs. RESULTS: A total of 128 responses (43%) were received. Of these, 53% of respondents were white and 47% were nonwhite and 34 (27%) were women and 94 (73%) were men. Fifty-seven percent of minorities anticipate a career in academic vascular surgery. There were no statistical differences between sex and ethnicity for factors influencing career choice, including training paradigm, presence of a life partner or dependents, mentorship role, participation in research, service, and teaching, anticipated salary, and debt burden (P > .05). Seventy-seven percent of respondents carry significant debt; of those with debt, 81% owe >$100,000 and 40% owe >$200,000. Seventy-three percent of 0+5 trainees anticipated choosing an academic practice compared with 42% of 5+2 trainees (P < .01). Respondents planning an academic career cited procedural variation, breadth and depth of practice/tertiary referral experience, and research opportunities as the most important drivers of career choice. Income potential, strength of the job market, and child care needs were deemed less important. CONCLUSIONS: This study shows that academic vascular surgery is a popular career option for current vascular surgery trainees, especially those in 0+5 programs. Choosing a career in academic vascular surgery appears not to be influenced by sex, ethnicity, child care concerns, salary expectations, or debt burden, even though most trainees carry enormous debt. The data imply future academic vascular surgeons will likely have greater gender and ethnic variability than is currently seen.