Circulating fibrillin fragment concentrations in patients with and without aortic pathology

Objective

Fragments of fibrillin-1 and fibrillin-2 will be detectable in the plasma of patients with aortic dissections and aneurysms. We sought to determine whether the plasma fibrillin fragment levels (PFFLs) differ between patients with thoracic aortic pathology and those presenting with nonaortic chest pain.

Methods

PFFLs were measured in patients with thoracic aortic aneurysm (n = 27) or dissection (n = 28). For comparison, patients without aortic pathology who had presented to the emergency department with acute chest pain (n = 281) were categorized into three groups according to the cause of the chest pain: ischemic cardiac chest pain; nonischemic cardiac chest pain; and noncardiac chest pain. The PFFLs were measured using a sandwich enzyme-linked immunosorbent assay.

Results

Fibrillin-1 fragments were detectable in all patients and were lowest in the ischemic cardiac chest pain group. Age, sex, and the presence of hypertension were associated with differences in fibrillin-1 fragment levels. Fibrillin-2 fragments were detected more often in the thoracic aneurysm and dissection groups than in the emergency department chest pain group (P < .0001). Patients with aortic dissection demonstrated a trend toward increased detectability (P = .051) and concentrations (P = .06) of fibrillin-2 fragments compared with patients with aortic aneurysms. Analysis of specific antibody pairs identified fibrillin-1 B15-HRP26 and fibrillin-2 B205-HRP143 as the most informative in distinguishing between the emergency department and aortic pathology groups.

Conclusions

Patients with thoracic aortic dissections demonstrated elevated plasma fibrillin-2 fragment levels (B205-HRP143) compared with patients presenting with ischemic or nonischemic cardiac chest pain and increased fibrillin-1 levels (B15-HRP26) compared with patients with ischemic cardiac chest pain. Investigation of fibrillin-1 and fibrillin-2 fragment generation might lead to diagnostic, therapeutic, and prognostic advances for patients with thoracic aortic dissection.

Duplex ultrasound and clinical outcomes of medical management of pediatric lower extremity arterial thrombosis

OBJECTIVES

Natural history and duplex ultrasound (DU) findings of pediatric lower extremity arterial thrombosis (PLEAT) are not well-defined. We describe acute and short-term DU findings of PLEAT to aid duplex interpretation and patient management.

METHODS

From August 2018 to April 2021 children with suspected PLEAT were identified prospectively. All had DU studies and were divided into group 1 (with DU-confirmed PLEAT) and group 2 (without DU-confirmed PLEAT). Patient demographics and DU findings were compared. Those with PLEAT and follow-up DU studies were also evaluated for recanalization and post recanalization DU findings.

RESULTS

We included 76 children (102 limbs) who had suspected PLEAT; 32 in group 1 and 44 group in 2. Fifty-seven percent had congenital heart disease, 26% a history prematurity (87%, 34% group 1; 11%, 14% group 2), with 14% of group 1 premature at PLEAT diagnosis and 68% aged less than 3 years-29 (94%) in group 1 and 23 (52%) in group 2. None had an arterial procedure to restore flow. Limb salvage was 100% with five group 1 mortalities unrelated to PLEAT. In group 1, 12 PLEATs were associated with an arterial line and 15 with cardiac catheterization. Occluded arteries included 7 external iliac, 20 common femoral, and 5 superficial femoral arteries (SFA). Peak systolic velocities (PSVs) distal to occluded segments in group 1 were lower than corresponding group 2 PSVs. SFA 18 ± 21 cm/s vs 84 ± 39 cm/s; popliteal artery (PA) 24 ± 18 cm/s vs 78 ± 38 cm/s; posterior tibial artery (PTA) 10 ± 8 cm/s versus 49 ± 27 cm/s (all P < .001). Twenty-one patients in group 1 had follow-up studies. Twelve (57%) were recanalized: 4 (19%) in less than 1 week and 10 (48%) by 6 months. Eighty-one percent of PLEATs were treated with anticoagulation (AC) and 57% recanalized. Fifty-nine percent of patients on AC recanalized, and 60% not on AC recanalized. Age, primary diagnosis, instrumentation type, and AC were not associated with failure to recanalize. After recanalization, PSVs in the CFA were not different than PSVs found in group 2 in the CFA (109 ± 50 cm/s vs 107 ± 57 cm/s; P = .88), but remained decreased in the SFA, PA, and PTA (SFA 68 ± 32 cm/s vs 83 ± 38 cm/s [P = .04]; PA 33 ± 13 cm/s vs 78 ± 37 [P = .0004]; and PTA 21 ± 8 cm/s vs 43 ± 20 cm/s [P = .0008]).

CONCLUSIONS

PLEAT occurs in young children, results in low distal PSVs, and often does not recanalize, but does not lead to short-term limb loss or mortality or necessarily require AC for recanalization. Normalization of CFA PSVs indicates recanalization while PSVs in segments distal to the CFA do not seem to return to normal.

A Novel Model of Tobacco Smoke-Mediated Aortic Injury

OBJECTIVE

Tobacco smoke exposure is a major risk factor for aortic aneurysm development. However, the initial aortic response to tobacco smoke, preceding aneurysm formation, is not well understood. We sought to create a model to determine the effect of solubilized tobacco smoke (STS) on the thoracic and abdominal aorta of mice as well as on cultured human aortic smooth muscle cells (HASMCs).

METHODS

Tobacco smoke was solubilized and delivered to mice via implanted osmotic minipumps. Twenty male C57BL/6 mice received STS or vehicle infusion. The descending thoracic, suprarenal abdominal, and infrarenal abdominal segments of the aorta were assessed for elastic lamellar damage, smooth muscle cell phenotype, and infiltration of inflammatory cells. Cultured HASMCs grown in media containing STS were compared to cells grown in standard media in order to verify our in vivo findings.

RESULTS

Tobacco smoke solution caused significantly more breaks in the elastic lamellae of the thoracic and abdominal aorta compared to control solution (P< .0001) without inciting an inflammatory infiltrate. Elastin breaks occurred more frequently in the abdominal aorta than the thoracic aorta (P < .01). Exposure to STS-induced aortic microdissections and downregulation of α-smooth muscle actin (α-SMA) by vascular smooth muscle cells (VSMCs). Treatment of cultured HASMCs with STS confirmed the decrease in α-SMA expression.

CONCLUSION

Delivery of STS via osmotic minipumps appears to be a promising model for investigating the early aortic response to tobacco smoke exposure. The initial effect of tobacco smoke exposure on the aorta is elastic lamellar damage and downregulation of (α-SMA) expression by VSMCs. Elastic lamellar damage occurs more frequently in the abdominal aorta than the thoracic aorta and does not seem to be mediated by the presence of macrophages or other inflammatory cells.

How patients interpret early signs of foot problems and reasons for delays in care: Findings from interviews with patients who have undergone toe amputations

Aims

To describe how patients respond to early signs of foot problems and the factors that result in delays in care.

Methods

Semi-structured interviews were conducted with a large sample of Veterans from across the United States with diabetes mellitus who had undergone a toe amputation. Data were analyzed using inductive content analysis.

Results

We interviewed 61 male patients. Mean age was 66 years, 41% were married, and 37% had a high school education or less. The patient-level factors related to delayed care included: 1) not knowing something was wrong, 2) misinterpreting symptoms, 3) “sudden” and “unexpected” illness progression, and 4) competing priorities getting in the way of care-seeking. The system-level factors included: 5) asking patients to watch it, 6) difficulty getting the right type of care when needed, and 7) distance to care and other transportation barriers.

Conclusion

A confluence of patient factors (e.g., not examining their feet regularly or thoroughly and/or not acting quickly when they noticed something was wrong) and system factors (e.g., absence of a mechanism to support patient’s appraisal of symptoms, lack of access to timely and convenient-located appointments) delayed care. Identifying patient- and system-level interventions that can shorten or eliminate care delays could help reduce rates of limb loss.

Ultrasound therapy for treatment of lower extremity intermittent claudication

BACKGROUND

While often thought of as a diagnostic tool, ultrasound (US) can also potentially be used as a therapeutic modality. US applies mechanical stress on endothelial cells and induces nitric oxide synthase, which regulates the secretion of nitric oxide, a potent vasodilator. In animal ischemic models, US has been shown to improve hindlimb, myocardial, and cerebral perfusion. We performed a pilot trial of US therapy in the lower extremities of human subjects with intermittent claudication.

METHODS

10 subjects (5 male, 5 female, mean age 69.7 ± 10.3) with intermittent claudication were recruited. Both legs were placed in a specially designed boot with a water interface between US transducers and the legs. Subjects underwent pulsed US therapy at 250 kHz frequency for 30 min for three treatments a week for six weeks. Pre and post treatment ankle:brachial index (ABI), 6-min walk (6 MW), Walking Impairment Questionnaire (WIQ), and Short Form 36 (SF36) were performed. Pre and post-treatment results were compared with paired t-test.

RESULTS

Six minute walking distance at baseline was 352 ± 70 m, after one treatment session 353 ± 70 m (p = 0.99), and at completion 372 ± 71 m (p = 0.015). There was a trend toward improved ABI after 6 weeks of treatment (0.53 ± 0.17 vs 0.64 ± 0.12, p = 0.083). After six weeks, significant improvements were noted in overall WIQ score (2.00 ± 1.48 vs 2.63 ± 1.38, p = 0.0001), WIQ (distance) 2.07 ± 1.54 vs 2.73 ± 1.42 (p = 0.036), and WIQ (stair) 2.00 ± 1.67 vs 2.62 ± 1.24, p = 0.034, with a trend in WIQ (speed), 1.89 ± 1.26 vs 2.46 ± 1.43, p = 0.069. In the SF-36, significant improvements were noted in the domains of physical functioning (44.0 ± 41.6 vs 50.5 ± 41.1, p = 0.009) and role limitations - physical (35.0 ± 48.3 vs 60.0 ± 49.6, p = 0.006) after six weeks.

CONCLUSIONS

Therapeutic US is a potential noninvasive treatment for intermittent claudication. Pilot study patients noted significant improvements in 6 MW and WIQ results after 6 weeks of treatment. A nonsignificant improvement in ABI was noted. Further research will be needed to clarify optimal treatment frequency and duration.

Immediate effects of hemodialysis on upper extremity and cognitive function

BACKGROUND

Subjects undergoing hemodialysis often describe feeling "weak" and "fatigued" after dialysis. This has not previously been quantified. We sought to evaluate upper extremity and cognitive function before and after hemodialysis to see if differences existed and how long recovery takes.

METHODS

Subjects undergoing hemodialysis in an inpatient hospital dialysis unit were recruited. Subjects underwent assessment of upper extremity strength (grip (GS) and pinch (PS)), dexterity (pegboard assembly (PA)), finger sensation (monofilaments), and cognitive function (mini-mental status exam (MMS)) immediately pre- and post-dialysis, 3 h post-dialysis, and the following morning. Both the dialysis (index) and non-dialysis extremities were evaluated. Results were also stratified for fistulas vs. central venous catheters. Patients were dialyzed at the same flow rate and duration.

RESULTS

21 subjects were evaluated, 13 (62%), male, mean age 56 ± 17 years, 15 (71%) diabetic, 15 (71%) fistulas, 6 (29%) central venous catheters. Overall, there were no significant changes in GS, PS, PA, immediately or 3 h after dialysis. MMS was non-significantly reduced 3 h after dialysis (22.8 ± 10.3 vs 27.0 ± 3.5, p = 0.06). PA was significantly improved the following morning (6.4 ± 4.8 assembled units vs 7.5 ± 5.1, p = 0.049). Patients dialyzing through catheters had reduced grip strength 3 h after dialysis compared to fistulas (-4.6 ± 2.7 N from baseline vs 1.4 ± 4.3 N from baseline, p = 0.018) that was resolved by the next day.

CONCLUSIONS

Hemodialysis in hospitalized inpatients does not cause acute objective deficits in upper extremity or cognitive function, with a significant improvement in hand dexterity the day after dialysis.

Improving follow-up of incomplete lower extremity venous duplex ultrasound examinations performed for deep and superficial vein thromboses

OBJECTIVE

A lower extremity venous duplex ultrasound (LEVDUS) examination is the standard diagnostic test to evaluate patients for lower extremity deep vein thrombosis (DVT). However, some studies will be incomplete for a variety of reasons, including patient-related factors such as pain, edema, a large leg circumference, or the presence of overlying bandages or orthopedic devices. We previously reported that the frequency of obtaining a follow-up examination after an incomplete and negative (I/N) LEVDUS examination was low but that the rates of DVT found on the follow-up studies of initially I/N LEVDUS studies were similar to the rates of DVT found with initially complete LEVDUS examinations. Therefore, we recommended process improvements to increase follow-up LEVDUS studies after an I/N LEVDUS examination. In the present study, we have described the results of appending a recommendation to obtain a follow-up LEVDUS study to preliminary and final reports of I/N LEVDUS.

METHODS

Starting in January 2019 through December 2019, a recommendation to obtain a repeat LEVDUS examination after an I/N study was appended to the preliminary and final reports of all I/N LEVDUS examination of patients who did not, otherwise, have an indication for anticoagulation (group 2). The patients were identified on an ongoing basis through the study period and entered into an Excel database (Microsoft Corp, Redmond, Wash). Group 2 was compared with a previously reported historic control cohort of patients identified from January 2017 to December 2017 (group 1). We compared groups 1 and 2 with respect to the frequency of the repeat studies performed within 4 weeks after an I/N LEVDUS examination and the DVT rates found from the follow-up LEVDUS examinations after an I/N LEVDUS study.

RESULTS

Of the patients in groups 1 and 2, 187 and 229 had had I/N LEVDUS examinations, with 28% and 40.2% of group 1 and 2 studies having follow-up LEVDUS examinations (P < .01). Previously unidentified lower extremity thrombi were discovered in 21% of the group 2 follow-up examinations. Also, the rate of new thrombi detected was not different between groups 2 and 1 (historic controls; DVT, 14.3% vs 18.5% [P = .25]; SVT, 6.3% vs 3.3% [P = .15]). A definitive finding of either positive or negative for DVT and SVT with a complete examination in 50% of the group 2 patients with follow-up examinations.

CONCLUSIONS

A recommendation to obtain a follow-up examination appended to the preliminary and final I/N LEVDUS reports was associated with an increased rate of follow-up examinations, which revealed many previously undetected DVTs and SVTs or had allowed for definitive exclusion of DVT.

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.

Predicting reamputation risk in patients undergoing lower extremity amputation due to the complications of peripheral artery disease and/or diabetes

Background

Patients undergoing amputation of the lower extremity for the complications of peripheral artery disease and/or diabetes are at risk of treatment failure and the need for reamputation at a higher level. The aim of this study was to develop a patient-specific reamputation risk prediction model.

Methods

Patients with incident unilateral transmetatarsal, transtibial or transfemoral amputation between 2004 and 2014 secondary to diabetes and/or peripheral artery disease, and who survived 12 months after amputation, were identified using Veterans Health Administration databases. Procedure codes and natural language processing were used to define subsequent ipsilateral reamputation at the same or higher level. Stepdown logistic regression was used to develop the prediction model. It was then evaluated for calibration and discrimination by evaluating the goodness of fit, area under the receiver operating characteristic curve (AUC) and discrimination slope.

Results

Some 5260 patients were identified, of whom 1283 (24·4 per cent) underwent ipsilateral reamputation in the 12 months after initial amputation. Crude reamputation risks were 40·3, 25·9 and 9·7 per cent in the transmetatarsal, transtibial and transfemoral groups respectively. The final prediction model included 11 predictors (amputation level, sex, smoking, alcohol, rest pain, use of outpatient anticoagulants, diabetes, chronic obstructive pulmonary disease, white blood cell count, kidney failure and previous revascularization), along with four interaction terms. Evaluation of the prediction characteristics indicated good model calibration with goodness-of-fit testing, good discrimination (AUC 0·72) and a discrimination slope of 11·2 per cent.

Conclusion

A prediction model was developed to calculate individual risk of primary healing failure and the need for reamputation surgery at each amputation level. This model may assist clinical decision-making regarding amputation-level selection.

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.

Characterization of profunda femoris vein thrombosis

OBJECTIVE

The incidence of and risk factors for profunda femoris vein (PFV) thrombosis are poorly characterized. We prospectively identified patients with PFV deep venous thrombosis (DVT) to characterize the demographics and anatomic distribution of proximal DVT in patients with PFV DVT.

METHODS

A prospective study was conducted of patients at a tertiary care university hospital with DVT diagnosed by venous duplex ultrasound scanning between June 2014 and June 2015. DVT patients were categorized as having PFV involvement (yes or no), and the anatomic distribution of other sites of ipsilateral venous thrombi was further stratified to determine whether there was external iliac vein (EIV), common femoral vein (CFV), or femoropopliteal vein (FPV) DVT. Demographic characteristics of the patients were compared between groups, PFV DVT vs proximal DVT without PFV DVT.

RESULTS

Of 4584 lower extremity venous duplex ultrasound studies performed, 398 (8.7%) scans were positive for proximal DVT from 260 patients; 23.1% of patients with DVT (60/260) had DVT involving the PFV. Of 112 patients who had CFV DVT, 55 (49.1%) also had ipsilateral involvement of the PFV. Of 60 patients with PFV DVT, 55 (91.7%) had involvement of the ipsilateral CFV. Patients in the PFV DVT group were more likely to have a history of a hypercoagulable disorder (26.7% vs 14.5%; P = .029) and a history of immobility (58.3% vs 42%; P = .026) compared with those with proximal DVT without PFV DVT. There were no differences in smoking, recent surgery, personal or family history of DVT, other medical comorbidities, inpatient status, or survival. There was no difference in laterality of DVT between the PFV DVT and proximal DVT without PFV DVT groups (35% vs 41.5% left, 35% vs 33.5% right, 30% vs 25% bilateral; P = .619). There was a higher proportion of PFV DVT with EIV involvement (21.7% vs 2.5%; P < .00001) and a higher proportion of PFV DVT with CFV + FPV involvement (65.0% vs 19%; P < .00001) compared with proximal DVT without PFV DVT. There was no difference in survival between the PFV DVT and proximal DVT without PFV DVT groups.

CONCLUSIONS

Patients with PFV thrombosis tend to have more thrombus burden with more frequent concurrent DVT in the EIV and FPV. Patients with PFV DVT are also more likely to have a history of hypercoagulable disorder and immobility. Ultrasound protocols for assessment of DVT should include routine examination of the PFV as a potential marker of a more virulent prothrombotic state.

Nonatherosclerotic vascular causes of acute abdominal pain

BACKGROUND

To examine the epidemiology, treatments, and outcomes of acute symptomatic non-atherosclerotic mesenteric vascular disease.

METHODS

Subjects were reviewed over a six year period. Categories included embolism (EM), dissection (DI), and aneurysm (AN). Presentation, demographics, treatment and outcomes were compared.

RESULTS

46 patients were identified (EM:20, AN:15, DI:11). Age at presentation differed (EM: 66.3, AN 62.4, DI 54.6, p < .05). EM more likely affected the superior mesenteric artery (EM80%, AN20%, DI45%, p = .002), DI hepatic artery (EM20%, AN13%, DI55%, p < .05), and AN mesenteric branches (EM5%, AN47%, DI0%; p = .001). EM more likely had history of arrhythmia (EM40%, AN7%, DI0%, p,0.05) and diarrhea (EM30%, AN7%, DI0%, p < .05). Treatment was most often surgical in EM (EM85%, AN33%, DI9%, p < .001), endovascular in AN (EM5%, AN40%, DI 9%, p < .02), and conservative in DI (EM15%, AN 33%, DI82%, p < .05). In hospital mortality was infrequent (EM10%, AN7%, DI0%, p = ns). Mean hospital length of stay differed by mechanism (EM13.6days, AN9.2, DI2.3, p = .005). Median follow up was 61 months. Survival at 1, 3 and 5 years for emboli was 75%, 70% and 59%, for aneurysms 93%, 86%, and 77%, and for dissections 100% at all time points (p = .043 log rank).

CONCLUSIONS

Patients with EM, AN, and DI differ in age, anatomic distribution and method of treatment. The etiology significantly affects long term survival.

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.

Intraluminal thrombus is associated with early rupture of abdominal aortic aneurysm

BACKGROUND

The implications of intraluminal thrombus (ILT) in abdominal aortic aneurysm (AAA) are currently unclear. Previous studies have demonstrated that ILT provides a biomechanical advantage by decreasing wall stress, whereas other studies have associated ILT with aortic wall weakening. It is further unclear why some aneurysms rupture at much smaller diameters than others. In this study, we sought to explore the association between ILT and risk of AAA rupture, particularly in small aneurysms.

METHODS

Patients were retrospectively identified and categorized by maximum aneurysm diameter and rupture status: small (<60 mm) or large (≥60 mm) and ruptured (rAAA) or nonruptured (non-rAAA). Three-dimensional AAA anatomy was digitally reconstructed from computed tomography angiograms for each patient. Finite element analysis was then performed to calculate peak wall stress (PWS) and mean wall stress (MWS) using the patient's systolic blood pressure. AAA geometric properties, including normalized ILT thickness (mean ILT thickness/maximum diameter) and % volume (100 × ILT volume/total AAA volume), were also quantified.

RESULTS

Patients with small rAAAs had PWS of 123 ± 51 kPa, which was significantly lower than that of patients with large rAAAs (242 ± 130 kPa; P = .04), small non-rAAAs (204 ± 60 kPa; P < .01), and large non-rAAAs (270 ± 106 kPa; P < .01). Patients with small rAAAs also had lower MWS (44 ± 14 kPa vs 82 ± 20 kPa; P < .02) compared with patients with large non-rAAAs. ILT % volume and normalized ILT thickness were greater in small rAAAs (68% ± 11%; 0.16 ± 0.04 mm) compared with small non-rAAAs (53% ± 16% [P = .02]; 0.11 ± 0.04 mm [P < .01]) and large non-rAAAs (57% ± 12% [P = .02]; 0.12 ± 0.03 mm [P < .01]). Increased ILT % volume was associated with both decreased MWS and decreased PWS.

CONCLUSIONS

This study found that although increased ILT is associated with lower MWS and PWS, it is also associated with aneurysm rupture at smaller diameters and lower stress. Therefore, the protective biomechanical advantage that ILT provides by lowering wall stress seems to be outweighed by weakening of the AAA wall, particularly in patients with small rAAAs. This study suggests that high ILT burden may be a surrogate marker of decreased aortic wall strength and a characteristic of high-risk small aneurysms.

Effect of systemic insulin treatment on diabetic wound healing

This study investigates if different diabetic treatment regimens affect diabetic foot ulcer healing. From January 2013 to December 2014, 107 diabetic foot ulcers in 85 patients were followed until wound healing, amputation or development of a nonhealing ulcer at the last follow-up visit. Demographic data, diabetic treatment regimens, presence of peripheral vascular disease, wound characteristics, and outcome were collected. Nonhealing wound was defined as major or minor amputation or those who did not have complete healing until the last observation. Median age was 60.0 years (range: 31.1-90.1 years) and 58 cases (68.2%) were males. Twenty-four cases reached a complete healing (healing rate: 22.4%). The median follow-up period in subjects with classified as having chronic wounds was 6.0 months (range: 0.7-21.8 months). Insulin treatment was a part of diabetes management in 52 (61.2%) cases. Insulin therapy significantly increased the wound healing rate (30.3% [20/66 ulcers] vs. 9.8% [4/41 ulcers]) (p = 0.013). In multivariate random-effect logistic regression model, adjusting for age, gender, smoking status, type of diabetes, hypertension, chronic kidney disease, peripheral arterial disease, oral hypoglycemic use, wound infection, involved side, presence of Charcot's deformity, gangrene, osteomyelitis on x-ray, and serum hemoglobin A1C levels, insulin treatment was associated with a higher chance of complete healing (beta ± SE: 15.2 ± 6.1, p = 0.013). Systemic insulin treatment can improve wound healing in diabetic ulcers after adjusting for multiple confounding covariates.

Predictive value of neutrophil-to-lymphocyte ratio in diabetic wound healing

OBJECTIVE

The neutrophil-to-lymphocyte ratio (NLR) has been used as a surrogate marker of systemic inflammation. We sought to investigate the association between NLR and wound healing in diabetic wounds.

METHODS

The outcomes of 120 diabetic foot ulcers in 101 patients referred from August 2011 to December 2014 were examined retrospectively. Demographic, patient-specific, and wound-specific variables as well as NLR at baseline visit were assessed. Outcomes were classified as ulcer healing, minor amputation, major amputation, and chronic ulcer.

RESULTS

The subjects' mean age was 59.4 ± 13.0 years, and 67 (66%) were male. Final outcome was complete healing in 24 ulcers (20%), minor amputation in 58 (48%) and major amputation in 16 (13%), and 22 chronic ulcers (18%) at the last follow-up (median follow-up time, 6.8 months). In multivariate analysis, higher NLR (odds ratio, 13.61; P = .01) was associated with higher odds of nonhealing.

CONCLUSIONS

NLR can predict odds of complete healing in diabetic foot ulcers independent of wound infection and other factors.

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.

Outcomes After Redo Procedures for Failed Mesenteric Revascularization

This report examines results of mesenteric revascularization following a failed splanchnic revascularization. Patients undergoing repeat mesenteric revascularization from January 1985 to July 2002 were identified from a prospectively maintained registry. Data recorded included procedures performed, perioperative mortality, complications, and operative indications. Patients who had embolic events were excluded. Eighty-six patients underwent 105 mesenteric interventions in this time period; 22 patients underwent 33 repeat mesenteric revascularization procedures. There were 25 single-vessel bypasses, 3 multivessel reconstructions, 3 angioplasty procedures (1 open, 2 percutaneous), and 2 graft thrombectomies. Complications occurred in 33.3%. Perioperative mortality was 6.1%, all in patients with acute mesenteric ischemia. One-and 4-year primary patency for repeat mesenteric revascularization was 73.5% and 62.2%, respectively, and survival for repeat mesenteric revascularization was 85.9% and 75.5%, respectively. Patients surgically treated for mesenteric ischemia can require additional interventions. Repeat revascularization effectively prolongs survival when an earlier intervention fails.

Carotid Surgery Following Previous Carotid Endarterectomy Is Safe and Effective

With the perceived high risk of repeat carotid surgery, carotid angioplasty and stenting have been advocated recently as the preferred treatment of recurrent carotid disease following carotid endarterectomy. An experience with the operative treatment of recurrent carotid disease to document the risks and benefits of this procedure is presented. A review of a prospectively acquired vascular registry over a 10-year period (Jan. 1990-Jan. 2000) was undertaken to identify patients undergoing repeat carotid surgery following previous carotid endarterectomy. All patients were treated with repeat carotid endarterectomy, carotid interposition graft, or subclavian-carotid bypass. The perioperative stroke and death rate, operative complications, life-table freedom from stroke, and rates of recurrent stenosis were documented. During the study period 56 patients underwent repeat carotid surgery, comprising 6% of all carotid operations during this period. The indication for operation was symptomatic disease recurrence in 41 cases (73%) and asymptomatic recurrent stenosis? 80% in 15 cases (27%). The average interval from the prior carotid endarterectomy to the repeat operation was 78 months (range 3 weeks-297 months). The operations performed included repeat carotid endarterectomy with patch angioplasty in 31 cases (55%), interposition grafts in 19 cases (34%), and subclavian-carotid bypass in 6 cases (11%). There were three perioperative strokes with one resulting in death for a perioperative stroke and death rate of 5.4%. One minor transient cranial nerve (CN IX) injury occurred. Mean follow-up was 29 months (range, 1-1 16 months). Life-table freedom from stroke was 95% at 1 year and 90% at 5 years. Recurrent stenosis (? 80%) developed in three patients (5.4%) during follow-up, including one internal carotid artery occlusion. Two patients (3.6%) underwent repeat surgery. Repeat surgery for recurrent cerebrovascular disease following carotid endarterectomy is safe and provides durable freedom from stroke. Most patients are candidates for repeat endarterectomy with patching, but interposition grafting is often required. These results strongly support the continued role of repeat carotid surgery in the treatment of recurrent carotid disease.

Endovascular Management of Paget-Schroetter Syndrome

Spontaneous thrombosis of the axillary and subclavian venous segments in young, healthy adults (effort thrombosis or Paget-Schroetter syndrome) is a rare but potentially disabling affliction. The diagnosis should be suspected in any young patient presenting with unilateral arm swelling. Typically, the dominant arm is affected, and frequent, repetitive arm use is a common component of the patients' history. Although the diagnosis can often be confirmed with a venous duplex evaluation, the central location of the venous abnormality occasionally mandates cross-sectional imaging or contrast venography to confirm the diagnosis. The underlying pathophysiology of this disorder is felt to be repetitive venous trauma owing to arm motion in the narrow anatomic space between the clavicle and first rib. The treatment of Paget-Schroetter syndrome is controversial and varies according to individual, institutional, and regional preferences. In general, the trend is toward more aggressive endovascular treatment. Prompt anticoagulation is generally accepted as the minimal treatment offered. Catheter-directed thrombolysis has also acquired a prominent role in reestablishing venous patency. The importance of relieving the anatomic compression of the subclavian vein by first rib resection remains controversial, with some experts advocating surgical intervention in all affected patients, whereas others perform this procedure selectively in cases of persistent venous stenosis or ongoing symptoms. Angioplasty with or without stenting is generally discouraged in the absence of anatomic decompression but may play an adjunctive role in patients undergoing first rib resection.

The Natural History of Indeterminate Blunt Cerebrovascular Injury

IMPORTANCE

The Denver criteria grade blunt cerebrovascular injuries (BCVIs) but fail to capture many patients with indeterminate findings on initial imaging.

OBJECTIVE

To evaluate outcomes and clinical significance of indeterminate BCVIs (iBCVIs).

DESIGN, SETTING, AND PARTICIPANTS

A retrospective review of all patients treated for BCVIs at our institution from January 1, 2007, through July 31, 2014, was completed. Patients were divided into 2 groups: those with true BCVIs as defined by the Denver criteria and those with iBCVIs, which was any initial imaging suggestive of a cerebrovascular arterial injury not classifiable by the Denver criteria.

MAIN OUTCOMES AND MEASURES

Primary outcomes were rate of resolution of iBCVIs, freedom from cerebrovascular accident (CVA) or transient ischemic attack (TIA), and 30-day mortality.

RESULTS

We identified 100 patients with 138 BCVIs: 79 with true BCVIs and 59 with iBCVIs. With serial imaging, 23 iBCVIs (39.0%) resolved and 21 (35.6%) remained indeterminate, whereas 15 (25.4%) progressed to true BCVI. The rate of CVA or TIA in the iBCVI group was 5.1% compared with 15.2% in the true BCVI group (P = .06). Of the 15 total CVAs or TIAs, 11 (73.3%) resulted from carotid injury and 4 (26.7%) from vertebral artery occlusion (P = .03). By Kaplan-Meier analysis, there was no difference in freedom from CVA or TIA for the 2 groups (P = .07). Median clinical follow-up was 91 days. Overall and 30-day mortality for the entire series were 17.4% and 15.2%, respectively. There was no difference in long-term or 30-day mortality between true BCVI and iBCVI groups.

CONCLUSIONS AND RELEVANCE

Detection of iBCVI has become a common clinical conundrum with improved and routine imaging. Indeterminate BCVI is not completely benign, with 25.4% demonstrating anatomical progression to true BCVI and 5.1% developing cerebrovascular symptoms. We therefore recommend serial imaging and antiplatelet therapy for iBCVI.

Genetics, Pregnancy, and Aortic Degeneration

We present a case of familial thoracic aortic aneurysm and dissection (FTAAD) in a pregnant female. FTAAD is an inherited, nonsyndromic aortopathy resulting from several genetic mutations critical to aortic wall integrity have been identified. One such mutation is the myosin heavy chain gene (MYH11) which is responsible for 1-2% of all FTAAD cases. This mutation results in aortic medial degeneration, loss of elastin, and reticulin fiber fragmentation predisposing to TAAD. Aortic disease is more aggressive during pregnancy as a result of increased wall stress from hyperdynamic cardiovascular changes and estrogen-induced aortic media degeneration. Our patient was a 29-year-old G2P1 woman at 26 weeks gestation presenting with abdominal and back pain. Work-up revealed a 6.4-cm ascending aortic aneurysm with a type A dissection extending into all arch vessels, aortic coarctation at the isthmus, and a separate focal type B aortic dissection with visceral involvement. Surgical management included concomitant cesarean section with delivery of a live premature infant, tubal ligation, ascending aortic replacement with reconstruction of the arch vessels, and aortic valve resuspension. The type B dissection was managed medically without complication. This is the first reported case of aortic dissection in a patient with FTAAD/MYH11 mutation and pregnancy. This case highlights that FTAAD and pregnancy cause aortic degeneration via distinct mechanisms and that hyperdynamics of pregnancy increase aortic wall stress. Management of pregnancy associated with aortopathy requires early transfer to a tertiary center, careful investigation to identify familial aortopathy, fetal monitoring, and a multidisciplinary team approach.

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.

Raynaud syndrome

Raynaud syndrome (RS) was first described by the French physician Maurice Raynaud in 1862 with the characteristic tricolor change featuring pallor (ischemic phase), cyanosis (deoxygenation phase), and erythema (reperfusion phase) induced by cold or stress. Although the underlying pathophysiological mechanism is unclear, alterations in activity of the peripheral adrenoceptor have been implicated, specifically an enhanced smooth muscle contraction due to overexpression or hyperactivity of postsynaptic alpha 2 receptors. There are 2 ways that RS can appear clinically; isolated, formerly referred as Raynaud disease or now primary RS and in association with other conditions, usually connective tissue disorders (eg, Sjögren syndrome, systemic lupus erythematosus, scleroderma, and rheumatoid arthritis), frequently called Raynaud phenomenon or secondary RS. The estimated prevalence in the general population is 3%-5%, with a higher prevalence in women than in men. The diagnosis is mainly clinical, based on patient descriptions of skin changes. Upper extremity pulse-volume recording is used to rule out proximal arterial obstruction. The differentiation between a vasospastic vs and obstructive mechanism is made using digital pressures and photoplethysmography, where an obstructive mechanism has decreased pressures and blunted waveforms. Cold challenge testing, such as ice water immersion with temperature recovery, is highly sensitive but lack specificity. Serologic screening (antinuclear antibody and rheumatoid factor) is advocated to rule out associated connective tissue disorders. Most patients with RS can be managed conservatively, with avoidance of cold exposure or hand warming. For those in whom conservative management is inadequate, a number of pharmacologic and surgical therapies have been used. Owing to lack of complete understanding of the underlying pathophysiology, targeted therapy has not been possible; rather, therapy has been focused on the use of general vasodilation strategies. In this review, the diagnosis, natural history, and current medical and invasive therapy are summarized.

Basic data underlying decision making in nonatherosclerotic causes of intermittent claudication

Although most cases of vasculogenic intermittent claudication are caused by atherosclerosis, there is an important minority of cases that are due to nonatherosclerotic causes. Because of their rarity and younger population affected, often without traditional atherosclerotic risk factors, there is frequently a significant delay in diagnosis of nonatherosclerotic peripheral arterial diseases by several months to years in some cases. Here, we review the literature on nonatherosclerotic causes of lower extremity claudication, symptoms, management including surgical and endovascular interventions, and outcomes. Conditions included are popliteal artery entrapment syndrome, cystic adventitial disease, pseudoxanthoma elasticum, persistent sciatic artery, fibromuscular disease, giant cell arteritis, iliac endofibrosis, neurogenic claudication, and chronic exertional compartment syndrome.

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.

A systematic review of assessment of skill acquisition and operative competency in vascular surgical training

OBJECTIVE

The aim of this systematic review is to describe the literature and assessment tools evaluating vascular surgical operative performance that could potentially be used for the assessment of educational outcomes applicable to the Milestone Project and the Next Accreditation System.

METHODS

A systematic review of PubMed/MEDLINE, EMBASE, PsycINFO, and key journals from 1985 to 2013 was performed to identify English-language articles describing assessment of vascular surgical skills and competence. Qualifying studies were abstracted for data concerning study aims, study and assessment setting, skills measured, and metrics used to determine competency. Strengths, weaknesses, and psychometric robustness of the assessment tools were determined.

RESULTS

The literature search identified 617 citations. After title and abstract review, 65 articles were retrieved for full-text assessment and 48 articles were included in the final review. Twenty-nine articles assessed open vascular skills; 19, endovascular skills; six, nontechnical skills; and one, teamwork skills. The majority (84%) of studies were performed in a simulated environment, four (8%) were performed in the operating room, and the remaining three were performed in both a simulated environment and an operating room. Strengths and weaknesses of assessment tools were study and assessor dependent, with none applicable to all study scenarios or procedures.

CONCLUSIONS

The literature describing assessment tools pertinent to vascular surgery is diverse. Existing assessment tools may be relevant to individual technical skill acquisition assessment; however, an operative assessment tool relevant to vascular/endovascular surgery and generalizable to the wide spectrum of technical and nontechnical skills pertinent to vascular surgery needs to be developed, validated, and implemented to allow the practical assessment of resident readiness to operate in an unsupervised setting.

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.