Multilevel thrombotic or embolic burden and its role in sex-related outcomes in acute limb ischemia

OBJECTIVE

The impact of sex upon outcomes in acute limb ischemia (ALI) remains disputed. We aim to quantify the effect of sex upon amputation-free survival (AFS) after a percutaneous-first approach for ALI.

METHODS

This was a two-center retrospective review of ALI managed via a percutaneous-first approach. Demographics, comorbidities, and clinical characteristics were analyzed. The Kaplan-Meier and Cox regression were used to estimate AFS, limb salvage, and overall survival.

RESULTS

Over 9 years, 170 patients (n = 87, 51% males; median age, 67 [interquartile range (IQR), 59-77 years) presented with ALI. Rutherford classification was I in 56 (33%); IIa in 85 (50%); IIb in 20 (12%), and III in 9 (5%). Thirty-day mortality, major amputation rate, and fasciotomy rates were 8% (n = 13); 6.5% (n = 11), and 4.7% (n = 8), respectively. Among revascularized limbs, 92% were patent at 30 days. Length of stay was 7 days (IQR, 3-11 days). Complications included 13 bleeding episodes (8%), four cases of atrial fibrillation (2%), and three re-thrombosis/clot extension events (1.7%). No differences were noted in complication rates when stratified by sex. Females were older than males (median age, 70 [IQR, 62-79] vs 65 [IQR, 56-76 years]; P = .02) and more likely to present with atrial fibrillation (20.5% vs 8%; P = .02) and hyperlipidemia (72% vs 57%; P = .04). Females also more frequently presented with multi-level thrombotic/embolic burden compared with males (56% vs 43%; P = .03) and required both aspiration thrombectomy and thrombolysis (27% vs 14%; P = .02). Kaplan-Meier estimated median AFS, limb salvage, and overall survival were 425 days (IQR, 140-824 days); 314 days (IQR, 72-727 days); and 342 days (IQR, 112-762 days). When stratified by sex, females had worse survival (median, 270 days [IQR, 92-636 days] vs 406 days [IQR, 140-937 days]; P = .005) and limb salvage (median, 241 days [IQR, 88-636 days] vs 363 days [IQR, 49-822 days]; P = .04) compared with males. Univariate Cox regression showed female sex (hazard ratio [HR], 1.46; 95% confidence interval [CI], 1.04-2.05; P = .03), multi-level thrombotic/embolic burden (HR, 1.64; 95% CI, 1.17-2.31; P = .004), and Rutherford class (HR, 1.37; 95% CI, 1.08-1.73; P = .009) predicted major amputation/death. By multivariable Cox regression, multi-level thrombotic/embolic burden (HR, 1.54; 95% CI, 1.09-2.17; P = .01), Rutherford class (HR, 1.34; 95% CI, 1.07-1.69; P = .01), and female sex (HR, 1.45; 95% CI, 1.03-2.05; P = .03) were each independently predictive of major amputation/death.

CONCLUSIONS

A percutaneous-first strategy is safe and efficacious in the overall ALI population. Similar to prior works, female vs male patients with ALI in our cohort have higher rates of mortality and major amputation. In our multivariable model, multi-level thrombotic/embolic burden was independently associated with a greater than 45% increased hazard of major amputation/death at last follow-up. Further prospective analysis is warranted to elucidate the underlying factors contributing to the higher prevalence of multi-level thrombotic/embolic burden in female patients with ALI, and to further define the optimal percutaneous-first approach for ALI in consideration of patient sex and extent of clot burden.

The role of big data, risk prediction, simulation, and centralization for emergency vascular problems: Lessons learned and future directions

Vascular specialists remain in high demand in current practice and commonly oversee care delivery for a variety of clinical emergencies. Accordingly, the contemporary vascular surgeon must be facile with treating a spectrum of problems, including a complex, heterogeneous group of acute arteriovenous thromboembolic and bleeding diatheses. It has been documented previously that there are substantial current workforce limitations placing constraints on vascular surgical care provision. Moreover, with the aging at-risk population, there remains a considerable national urgency to improve timely diagnoses, specialty consultation, and appropriate transfer of patients to centers of excellence capable of providing a comprehensive compendium of emergency vascular services. Clinical decision aids, simulation training, and regionalization of nonelective vascular problems are all strategies that have been increasingly recognized to address these service gaps. Notably, clinical research in vascular surgery has traditionally focused on identification of patient- and procedure-related factors that influence outcomes by using resource-intensive causal inference methodology. By comparison, large data sets have only more recently been recognized to be a valuable tool that can provide heuristic algorithms to address more complex health care problems. Such data can be manipulated to generate clinical risk scores and decision aids, as well as robust outcome descriptions, which stand to inform stakeholders regarding best practice. The purpose of this review was to provide a robust overview of the lessons derived from the application of big data, risk prediction, and simulation in the management of vascular emergencies.

Outcomes of vascular trauma associated with an evolution in the use of endovascular management

BACKGROUND

The availability of endovascular techniques has led to a paradigm shift in the management of vascular injury. While previous reports showed trends towards the increased use of catheter-based techniques, there have been no contemporary studies of practice patterns and how these approaches differ by anatomic distributions of injury. The objective of this study is to provide a temporal assessment of the use of endovascular techniques in the management of torso, junctional (subclavian, axillary, iliac), and extremity injury and to evaluate any association with survival and length of stay.

METHODS

The American Association for the Surgery of Trauma (AAST) Prospective Observational Vascular Injury Treatment registry (PROOVIT) is the only large multicenter database focusing specifically on the management of vascular trauma. Patients in the AAST PROOVIT registry from 2013-2019 with arterial injuries were queried, and radial/ulnar, and tibial artery injuries were excluded. The primary aim was to evaluate the frequency in use of endovascular techniques over time and by body region. A secondary analysis evaluated the trends for junctional injuries and compared the mortality between those treated with open vs. endovascular repair.

RESULTS

Of the 3,249 patients included, 76% were male, and overall treatment type was 42% nonoperative, 44% open, 14% endovascular. Endovascular treatment increased an average of 2% per year from 2013-2019 (Range: 17-35%, R² =.61). The use of endovascular techniques for junctional injuries increased by 5% per year (Range: 33%-63%, R² =.89). Endovascular treatment was more common for thoracic, abdominal, and cerebrovascular injuries, and least likely in upper and lower extremity injuries. Injury severity score (ISS) was higher for patients receiving endovascular repair in every vascular bed except lower extremity. Endovascular repair was associated with significantly lower mortality than open repair for thoracic (5% vs. 46%, p<.001) and abdominal injuries (15% vs 38%, p<.001). For junctional injuries, endovascular repair was associated with a non-statistically significant lower mortality (19% vs. 29%, p=.099), despite higher ISS (25 vs. 21, p=.003) compared to open repair.

CONCLUSION

The reported use of endovascular techniques within the PROOVIT registry increased more than 10% over a 6-year period. This increase was associated with improved survival, especially for patients with junctional vascular injuries. Practices and training programs should account for these changes by providing access to endovascular technologies and instruction in the catheter-based skill sets to optimize outcomes in the future.

Contrast-enhanced CT radiomics improves the prediction of abdominal aortic aneurysm progression

OBJECTIVES

To determine if three-dimensional (3D) radiomic features of contrast-enhanced CT (CECT) images improve prediction of rapid abdominal aortic aneurysm (AAA) growth.

METHODS

This longitudinal cohort study retrospectively analyzed 195 consecutive patients (mean age, 72.4 years ± 9.1) with a baseline CECT and a subsequent CT or MR at least 6 months later. 3D radiomic features were measured for 3 regions of the AAA, viz. the vessel lumen only; the intraluminal thrombus (ILT) and aortic wall only; and the entire AAA sac (lumen, ILT, and wall). Multiple machine learning (ML) models to predict rapid growth, defined as the upper tercile of observed growth (> 0.25 cm/year), were developed using data from 60% of the patients. Diagnostic accuracy was evaluated using the area under the receiver operating characteristic curve (AUC) in the remaining 40% of patients.

RESULTS

The median AAA maximum diameter was 3.9 cm (interquartile range [IQR], 3.3-4.4 cm) at baseline and 4.4 cm (IQR, 3.7-5.4 cm) at the mean follow-up time of 3.2 ± 2.4 years (range, 0.5-9 years). A logistic regression model using 7 radiomic features of the ILT and wall had the highest AUC (0.83; 95% confidence interval [CI], 0.73-0.88) in the development cohort. In the independent test cohort, this model had a statistically significantly higher AUC than a model including maximum diameter, AAA volume, and relevant clinical factors (AUC = 0.78, 95% CI, 0.67-0.87 vs AUC = 0.69, 95% CI, 0.57-0.79; p = 0.04).

CONCLUSION

A radiomics-based method focused on the ILT and wall improved prediction of rapid AAA growth from CECT imaging.

KEY POINTS

• Radiomic analysis of 195 abdominal CECT revealed that an ML-based model that included textural features of intraluminal thrombus (if present) and aortic wall improved prediction of rapid AAA progression compared to maximum diameter. • Predictive accuracy was higher when radiomic features were obtained from the thrombus and wall as opposed to the entire AAA sac (including lumen), or the lumen alone. • Logistic regression of selected radiomic features yielded similar accuracy to predict rapid AAA progression as random forests or support vector machines.

Extensive thrombosis with amputation of digit I pedis dextra: A case report in Indonesian adult with type 2 diabetes mellitus

Background

Diabetes mellitus (DM) is a risk factor for vascularization disorders, especially in the lower extremity that causes acute limb infection (ALI) and chronic limb ischemia (CLI).

Case presentation

A 41-year-old man has acute limb ischemia, critical limb ischemia, and diabetes mellitus. Investigation results showed vascular disorders in the lower extremity area with necrosis of the digit I pedis destra. The patient underwent retrograde and antegrade thrombectomy of the right to left femoral artery and amputation of the digit pedis.

Discussion

Thrombectomy is still effective for the management of extensive thrombosis. Amputation of necrotic tissue needs to be conducted immediately to prevent infection.

Conclusion

Vascular disorders in the extremities are an urgent health problem that requires immediate treatment because it prevents damage to the function of the lower extremities.

•

Thrombectomy for vascular disorders in the lower extremity can minimize necrosis.

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Amputation is a solution to prevent sepsis in patients with diabetes mellitus.

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In addition to surgery, anti-thrombus should be given regularly.

Balloon-Assisted Endovascular Thrombectomy for Tibial Thromboembolism

We present a novel approach to endovascular thrombectomy using the Penumbra Indigo® Aspiration System with balloon assistance for a thromboembolic occlusion to the tibioperoneal trunk and tibial arteries causing acute limb ischemia. This technique allows for effective suction thrombectomy of distal vessels into a shorter, large-diameter aspiration catheter, thereby overcoming the limitations of the longer but smaller aspiration catheters.

Safety and efficacy of an endovascular-first approach to acute limb ischemia

BACKGROUND

The optimal techniques to manage acute limb ischemia (ALI) remain unclear. Previous reports have suggested that the decreased morbidity and mortality of endovascular approaches are mitigated by the limited technical success rates relative to open or hybrid approaches for ALI. However, these data failed to include newer technologies that might improve the technical success rates. We, therefore, sought to describe the current outcomes for an endovascular-first approach to ALI.

METHODS

We performed a single-center, single-arm, retrospective cohort study of consecutive patients with ALI from 2015 to 2018. Technical success, limb salvage, survival, patency, and length of stay were quantified using Kaplan-Meier (KM) analysis. Cox regression analysis was used to identify the predictors of amputation-free survival.

RESULTS

During the 3 years, 60 consecutive patients (39 men [65%]; median age, 65 years) presented with ALI. The Rutherford class was I in 15 patients (25%), IIa in 23 (38%), IIb in 13 (22%), and III in 9 patients (15%). Of the 60 patients, 34 had a history of previous failed ipsilateral revascularization (56%), including open bypass for 8 (13%), endovascular for 8 (13%), and both open and endovascular intervention for 18 (30%). The endovascular-first approach procedures included catheter-directed thrombolysis only (n = 19; 3%), catheter-directed thrombolysis plus aspiration and/or rheolytic thrombectomy (n = 19; 32%), and aspiration and/or rheolytic thrombectomy (n = 16; 26%). Six patients (10%) underwent covered stent placement only. The underlying occlusive process was most often thrombosis of a previous bypass graft or stent in 32 patients (53%), followed by native vessel thrombosis in 15 (25%). ALI had resulted from embolism in 13 patients (21.7%), including 2 (3%) with embolization to occlude a previous bypass graft or stent. Technical success was achieved in 58 patients (97%), with open conversion required in two patients (3%). At 30 days postoperatively, 52 patients (87%) survived, and 53 (88%) had successful limb salvage. Five patients (8%) had required four-compartment fasciotomy. No major hemorrhagic complications developed. The median length of stay overall and in the intensive care unit was 9 days (interquartile range, 4-14 days) and 2 days (interquartile range, 1-5 days), respectively. At 1 year, the KM estimates were as follows: amputation-free survival, 58% ± 0.08%; limb salvage, 74.3% ± 0.07%; and survival, 73.3% ± 0.07%. The 1-year KM estimates for primary and secondary patency were 39.4% ± 0.08% and 78.2% ± 0.07%, respectively. On multivariable Cox regression analysis, only age independently predicted for death and/or amputation at the last follow-up (hazard ratio, 1.06; 95% confidence interval, 1.01-1.10; P = .01).

CONCLUSIONS

The current endovascular approaches to ALI have high technical success rates. Survival, limb salvage, perioperative complications, and length of stay were similar to those from previous reports of historical open cohorts. Further prospective, appropriately powered, multicenter cohort studies are warranted to evaluate the efficacy of endovascular vs open approaches to ALI.