Loss Of Patency Research Articles

Predicting Outcomes Following Lower Extremity Open Revascularization Using Machine Learning

Lower extremity open revascularization carries significant peri-operative risks; however, outcome prediction tools remain limited. Using machine learning (ML), we developed automated algorithms that predict 30-day outcomes following lower extremity open revascularization. In this multicenter retrospective cohort study, the American College of Surgeons National Surgical Quality Improvement Program-targeted database was used to identify patients who underwent lower extremity infrainguinal open revascularization for atherosclerotic disease between 2011 and 2021. Patients treated for lower extremity aneurysmal disease, acute limb ischemia, trauma, dissection, or malignancy were excluded. Input features included 37 preoperative demographic and clinical variables. The primary outcome was 30-day major adverse limb event (MALE; composite of untreated loss of patency, major reintervention, or major amputation) or death. The 30-day secondary outcomes were individual components of the primary outcome, major adverse cardiovascular event, wound complication, bleeding, other morbidity, nonhome discharge, and unplanned readmission. Our data were split into training (70%) and test (30%) sets. Using 10-fold cross-validation, we trained six ML models using preoperative features. The primary model evaluation metric was area under the receiver operating characteristic curve (AUROC). Model robustness was evaluated with calibration plot and Brier score. Variable importance scores were calculated to determine the top 10 predictive features. Performance was assessed on subgroups based on age, sex, race, ethnicity, symptom status, procedure type, and urgency. Overall, 24,309 patients were included. Thirty-day MALE or death occurred in 2349 (9.3%) patients. Those who developed the primary outcome were older with more comorbidities, had poorer functional status, and were more likely to have high risk physiologic and anatomical features. Our best performing prediction model for 30-day MALE or death was XGBoost, achieving an AUROC of 0.93 (95% confidence interval [CI], 0.92-0.94) (Fig 1). In comparison, logistic regression had an area under the receiver operating characteristic curve of 0.63 (95% CI, 0.61-0.65). For secondary outcomes, XGBoost achieved area under the receiver operating characteristic curves between 0.87 and 0.96. The calibration plot showed good agreement between predicted and observed event probabilities with a Brier score of 0.08 (Fig 2). The strongest predictive feature in our algorithm was symptom status (chronic limb-threatening ischemia). Model performance remained robust on all subgroup analyses of specific demographic and clinical populations. Our ML models accurately predict 30-day outcomes following lower extremity open revascularization using preoperative data, performing better than logistic regression. They have potential for important utility in guiding risk mitigation strategies for patients being considered for lower extremity open revascularization to improve outcomes and reduce costs.Fig 2Calibration plot with Brier score for predicting 30-day major adverse limb event (MAKE) or death following lower extremity open revascularization using Extreme Gradient Boosting (XGBoost) model.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Fate of target visceral vessels in fenestrated and branched complex endovascular aortic repair

ObjectiveTo assess branch vessel outcomes after endovascular repair of complex aortic aneurysms analyzing possible factors influencing early and long-term results. MethodsThe Italian Multicentre Fenestrated and Branched registry enrolled 596 consecutive patients treated with fenestrated and branched endografts for complex aortic disease from January 2008 to December 2019 by four Italian academic centers. The primary end points of the study were technical success (defined as target visceral vessel [TVV] patency and absence of bridging device-related endoleak at final intraoperative control), and freedom from TVV instability (defined as the combined results of type IC/IIIC endoleaks and patency loss) during follow-up. Secondary end points were overall survival and TVV-related reinterventions. ResultsWe excluded 591 patients (3 patients with a surgical debranching and 2 patients who died before completion from the study cohort) were treated for a total of 1991 visceral vessels targeted by either a directional branch or a fenestration. The overall technical success rate was 98.4%. Failure was related to the use of an off-the-shelf (OTS) device (custom-made device vs OTS, HR, 0.220; P = .007) and a preoperative TVV stenosis of >50% (HR, 12.460; P < .001). The mean follow-up time was 25.1 months (interquartile range, 3-39 months). The overall estimated survival rates were 87%, 77.4%, and 67.8% at 1, 3, and 5 years, respectively (standard error [SE], 0.015, 0.022, and 0.032). During follow-up, TVV branch instability was observed in 91 vessels (5%): 48 type IC/IIIC endoleaks (2.6%) and 43 stenoses-thromboses (2.4%). The extent of aneurysm disease (thoracoabdominal aortic aneurysm [TAAA] types I-III vs TAAA type IV/juxtarenal aortic aneurysm/pararenal aortic aneurysm) was the only independent predictor for developing a TVV-related type IC/IIIC endoleak (HR, 3.899; 95% confidence interval [CI]:, 1.924-7.900; P < .001). Risk of patency loss was independently associated with branch configuration (HR, 8.883; P < .001; 95% CI, 3.750-21.043) and renal arteries (HR, 2.848; P = .030; 95% CI, 1.108-7.319). Estimated rates at 1, 3, and 5 years of freedom from TVV instability and freedom from TVV-related reintervention were 96.6%, 93.8%, and 90% (SE, 0.005, 0.007, and 0.014) and 97.4%, 95.0%, and 91.6% (SE, 0.004, 0.007, and 0.013), respectively. ConclusionsIntraoperative failure to bridge a TVV was associated with a preoperative TVV stenosis of >50% and the use of OTS devices. Midterm outcomes were satisfying, with an estimated 5-year freedom from TVV instability and reintervention of 90.0% and 91.6%, respectively. During follow-up, the larger extent of aneurysm disease was associated with an increased risk of TVV-related endoleaks, whereas a branch configuration and renal arteries were more prone to patency loss.

Brachiocephalic and Radiocephalic Arteriovenous Fistulas in Patients with Tunneled Dialysis Catheters Have Similar Outcomes

Patients with tunneled dialysis catheters (TDCs) have a time-sensitive need for afunctional permanent access due to high risk of catheter-associated morbidity. Brachiocephalic arteriovenous fistulas (BCF) have been reported to have higher maturation and patency compared to radiocephalic arteriovenous fistulas (RCF), although more distal creation is encouraged when possible. However, this may lead to a delay in establishing permanent vascular access and, ultimately, TDC removal. Our goal was to assess short-term outcomes after BCF and RCF creation for patients with concurrent TDCs to see if these patients would potentially benefit more from an initial brachiocephalic access to minimize TDC dependence. The Vascular Quality Initiative hemodialysis registry was analyzed from 2011 to2018. Patient demographics, comorbidities, access type, and short-term outcomes including occlusion, reinterventions, and access being used for dialysis, were assessed. There were 2,359 patients with TDC, of whom 1,389 (58.9%) underwent BCF creation and 970 (41.1%) underwent RCF creation. Average patient age was 59years, and 62.8% were male. Compared with RCF, those with BCF were more often older, of female sex, obese, nonindependently ambulatory, have commercial insurance, diabetes, coronary artery disease, chronic obstructive pulmonary disease, be on anticoagulation, and have a cephalic vein diameter of ≥3mm (all P<0.05). Kaplan-Meier analysis for 1-year outcomes for BCF and RCF, respectively, showed that primary patency was 45% vs. 41.3% (P=0.88), primary assisted patency was 86.7% vs. 86.9% (P=0.64), freedom from reintervention was 51.1% vs. 46.3% (P=0.44), and survival was 81.3% vs. 84.9% (P=0.02). Multivariable analysis showed that BCF was comparable to RCF with respect to primary patency loss (hazard ratio [HR] 1.11, 95% confidence interval [CI] 0.91-1.36, P=0.316), primary assisted patency loss (HR 1.11, 95% CI 0.72-1.29, P=0.66), and reintervention (HR 1.01, 95% CI 0.81-1.27, P=0.92). Access being used at 3months was similar but trending towards RCF being used more often (odds ratio 0.7, 95% CI 0.49-1, P=0.05). BCFs do not have superior fistula maturation and patency compared to RCFs in patients with concurrent TDCs. Creation of radial access, when possible, does not prolong TDC dependence.

Trends in Utilization of Completion Imaging after Lower Extremity Bypass and Its Association with Major Adverse Limb Events and Loss of Primary Patency

Failure following lower extremity bypasses (LEBs) isoften secondary to technical defects. Despite traditional teachings, routine use of completion imaging (CI) in LEB has been debated. This study assesses national trends of CI following LEBs and the association of routine CI with 1-year major adverse limb events (MALE) and 1-year loss of primary patency (LPP). The Vascular Quality Initiative (VQI) LEB dataset from 2003-2020 was queried for patients who underwent elective bypass for occlusive disease. The cohort was divided based on surgeons' CI strategy at time of LEB, categorized as routine (≥80% of cases/year), selective (<80% of cases/year), or never. The cohort was further stratified by surgeon volume category [low (<25th percentile), medium (25th-75th percentile), or high (>75th percentile)]. The primary outcomes were 1-year MALE-free survival and 1-year loss of primary patency (LPP)-free survival. Our secondary outcomes were temporal trends in CI use and temporal trends in 1-year MALE rates. Standard statistical methods were utilized. We identified 37,919 LEBs; 7,143 in routine CI strategy cohort, 22,157 selective CI and 8,619 in never CI. Patients in the 3 cohorts had comparable baseline demographics and indications for bypass. There was a significant decrease in CI utilization from 77.2% in 2003 to 32.0% in 2020 (P<0.001). Similar trends in CI use were observed in patients who underwent bypass to tibial outflows (86.0% in 2003 vs. 36.9% in 2020; P<0.001). While the use of CI has decreased over time, 1-year MALE rates have increased from 44.4% in 2003 to 50.4% in 2020 (P<0.001). On multivariate COX regression, however, no significant associations between CI use or CI strategy and risk of 1-year MALE or LPP was found. Procedures performed by high-volume surgeons carried a lower risk of 1-year MALE (HR: 0.84; 95% CI [0.75-0.95]; P=0.006) and LPP (HR:0.83; 95% CI [0.71-0.97]; P<0.001) compared to low-volume surgeons. Repeat adjusted analyses showed no association between CI (use or strategy) and our primary outcomes when the subgroups with tibial outflows were analyzed. Similarly, no associations were found between CI (use or strategy) and our primary outcomes when the subgroups based on surgeons' CI volume were evaluated. The use of CI, for both proximal and distal target bypasses, has decreased over time while 1-year MALE rates have increased. Adjusted analyses indicate no association between CI use and improved MALE or LPP survival at 1year and all CI strategies were found to have equivalent outcomes.

To patch, or not to patch a common femoral artery, that is the question.

There is no strong evidence to support or reject the use of patch angioplasty (PA) after femoral endarterectomy (FE). The current study aimed to assess early postoperative complications and compare primary patency (PP) rates after FE in patients treated with PA versus direct closure (DC). This is a retrospective study of patients admitted during 06/2002-07/2017 with signs and symptoms of chronic lower limb ischemia (Rutherford categories 2-6). Patients with angiographically confirmed stenoses or occlusions of the common femoral arteries (CFAs) and managed with FE with or without PA were included in the study. Early postoperative wound complications were assessed. The PP analysis was based on imaging-confirmed data. The impact of PA on the patency was evaluated in a confounder-adjusted Cox regression model. PP rates were compared with log-rank between the PA and DC groups using Kaplan-Meier survival analysis in the propensity score-matched (PSM) cohorts. A total of 295 primary FEs were identified. The patients' median age was 75years. A total of 210 patients were managed with PA and 85 with DC. Altogether, 38 (12.9%) local wound complications were registered, 15 (5.1%) of which required re-interventions. There were 9 (3.2%) cases of deep wound infection, 20 (7.0%) seromas, and 11 (3.9%) cases of major bleeding, with no significant difference between the PA and DC groups. All of the infected patches were made of synthetic material, and 83% of them were removed. The PP analysis was performed on 50 PSM patient pairs with a median age of 74years. The median imaging-confirmed follow-up lengths were 77months (IQR = 47months) for the PA patients and 27months (IQR = 64months) for the DC patients. The preoperative median diameter of the CFA was 8.8mm (IQR = 3.4). The 5year primary patency rates of CFAs with a minimum diameter of 5.5mm managed with PA or DC exceeded 91%, p > 0.05. Female sex was associated with the loss of PP, odds ratio 4.17, p = 0.046. Wound complications after FE with or without patching are not uncommon and often lead to reoperations. The PP rates of CFAs with a minimum diameter of 5.5mm and accomplished with or without patching are comparable. Female sex is associated with the loss of patency.

Outcomes of the Gore® Excluder® Iliac Branch Endoprosthesis Using Self Expanding or Balloon-Expandable Stent Grafts for the Internal Iliac Artery Component

Objective: The GORE® EXCLUDER® Iliac Branch Endoprosthesis (IBE; W.L. Gore & Associates, Flagstaff, Arizona) was developed to be used in combination with a self-expanding stent graft (SESG) for the internal iliac artery (IIA) bridging stent. Balloon-expandable stent grafts (BESGs) are an alternative for the IIA, offering advantages in sizing, device tracking, precision, and lower profile delivery. We compared the performance of SESG and BESG when used as the IIA bridging stent in patients undergoing EVAR with IBE. Methods: This is a retrospective review of consecutive patients who underwent EVAR with IBE implantation at a single center from October 2016 to May 2021. Anatomic and procedural characteristics were recorded via chart review and computed tomography (CT) postprocessing software (Vitrea® v7.14). Devices were assigned to SESG vs. BESG groups based on the type of device landing into the most distal IIA segment. Analysis was performed per device to account for patients undergoing bilateral IBE. The primary endpoint was IIA patency, and secondary endpoint was IBE-related endoleak. Results: During the study period, 48 IBE devices were implanted in 41 patients (mean age 71.1 years). All IBE devices were implanted in conjunction with an infrarenal endograft. There were 24 devices in each of the self-expanding internal iliac component (SE-IIC) and balloon-expandable internal iliac component (BE-IIC) groups. The BE-IIC group had smaller diameter IIA target vessels (11.6±2.0 mm vs. 8.4±1.7 mm, p<0.001). Mean follow-up was 525 days. Loss of IIA patency occurred in 2 SESG devices (8.33%) at 73 and 180 days postprocedure, and in zero BESG devices, however, this difference was not statistically significant (p=0.16). There was 1 IBE-related endoleak requiring reintervention during the study period. A BESG device required reintervention due to Type 3 endoleak at 284 days. Conclusions: There were no significant differences in outcomes between SESG and BESG when used for the IIA bridging stent in EVAR with IBE. The BESGs were associated with using 2 IIA bridging stents and were more often deployed in smaller IIA target arteries. Retrospective study design and small sample size may limit the generalizability of our findings. Clinical Impact This series compares postoperative and midterm outcomes of self expanding stent grafts and balloon expandable stent grafts (BESG) when used as the internal iliac stent graft as part of a Gore® Excluder® Iliac Branch Endoprosthesis (IBE). With similar outcomes between the two stent-grafts, our series suggests that some of the advantages of BESG, device sizing, tracking, deployment, and profile, may be able to be leveraged without impacting the mid-term performance of the IBE.

The Effect of Chronic and End-Stage Renal Disease on Long-Term Outcomes after Infrainguinal Bypass

Patients undergoing infrainguinal bypass for chronic limb threatening ischemia (CLTI) with renal dysfunction are at an increased risk for perioperative and long-term morbidity and mortality. Our goal was to examine perioperative and 3-year outcomes after lower extremity bypass for CLTI stratified by kidney function. A retrospective, single-center analysis of lower extremity bypass for CLTI was performed between 2008 and 2019. Kidney function was categorized as normal (estimated glomerular filtration rate (eGFR) ≥60mL/min/1.73m2), chronic kidney disease (CKD) (eGFR 15-59mL/min/1.73m2), and end-stage renal disease (ESRD) (eGFR <15mL/min/1.73m2). Kaplan-Meier and multivariable analysis were performed. There were 221 infrainguinal bypasses performed for CLTI. Patients were classified by renal function as normal (59.7%), CKD (24.4%), and ESRD (15.8%). Average age was 66years and 65% were male. Overall, 77% had tissue loss with 9%, 45%, 24%, and 22% being Wound, Ischemia, and foot Infection stages 1-4, respectively. The majority (58%) of bypass targets was infrapopliteal and 58% used ipsilateral greater saphenous vein. The 90-day mortality and readmission rates were 2.7% and 49.8%, respectively. ESRD, compared to CKD and normal renal function, respectively, had the highest 90-day mortality (11.4% vs. 1.9% vs. 0.8%, P=0.002) and 90-day readmission (69% vs. 55% vs. 43%, P=0.017). On multivariable analysis, ESRD, but not CKD, was associated with higher 90-day mortality (odds ratio (OR) 16.9, 95% confidence interval (CI) 1.83-156.6, P=0.013) and 90-day readmission (OR 3.02, 95% CI 1.2-7.58, P=0.019). Kaplan-Meier 3-year analysis showed no difference between groups for primary patency or major amputation; however, ESRD, compared to CKD and normal renal function, respectively, had worse primary-assisted patency (60% vs. 76% vs. 84%, P=0.03) and survival (72% vs. 96% vs. 94%, P=0.001). On multivariable analysis, ESRD and CKD were not associated with 3-year primary patency loss/death, but ESRD was associated with higher primary-assisted patency loss (hazard ratio (HR) 2.61, 95% CI 1.23-5.53, P=0.012). ESRD and CKD were not associated with 3-year major amputation/death. ESRD was associated with higher 3-year mortality (HR 4.95, 95% CI 1.52-16.2, P=0.008) while CKD was not. ESRD, but not CKD, was associated with higher perioperative and long-term mortality after lower extremity bypass for CLTI. Although ESRD was associated with lower long-term primary-assisted patency, there were no differences in loss of primary patency or major amputation.

Long-Term Outcomes of the Covered Endovascular Reconstruction of the Aortic Bifurcation (CERAB) Technique in Patients With Aorto-Iliac Occlusive Disease.

The Covered Endovascular Reconstruction of the Aortic Bifurcation (CERAB) reconstruction is an endovascular technique, developed to reconstruct the aortic bifurcation in the most optimal anatomical and physiological manner. Short-term data were promising, but long-term data are still lacking. The objective was to report the long-term outcomes of CERAB for extensive aorto-iliac occlusive disease and to identify predictors for loss of primary patency. Consecutive electively treated patients with CERAB for aorto-iliac occlusive disease in a single hospital were identified and analyzed. Baseline and procedural data and follow-up were collected at 6-weeks, 6 months, 12 months, and annually thereafter. Technical success, procedural, and 30-day complications were evaluated, as well as overall survival. Patency and freedom from target lesion revascularization rates were analyzed using Kaplan Meier curves. Uni- and multivariate analysis were performed to identify possible predictors of failure. One hundred and sixty patients were included (79 male). Indication for treatment was intermittent claudication for 121 patients (75.6%) and 133 patients (83.1%) had a TASC-II D lesion. Technical success was obtained in 95.6% of patients and the 30-day mortality rate was 1.3%. The 5-year primary, primary-assisted, and secondary patency rates were 77.5%, 88.1%, and 95.0%, respectively, with a freedom-from clinically driven target lesion revascularization (CD-TLR) rate of 84.4%. The strongest predictor of loss of primary patency of CERAB was a previous aorto-iliac intervention (odds ratio [OR]=5.36 (95% confidence interval [CI]: 1.30; 22.07), p=0.020). In patients not previously treated in the aorto-iliac tract, 5-year primary, primary assisted, and secondary patency rates were 85.1%, 94.4%, and 96.9%, respectively. At 5-year follow-up, an improved Rutherford was found in 97.9% of patients and the freedom from major amputation rate was 100%. The CERAB technique is related to good long-term outcomes, particularly in primary cases. In patients that had prior treatment for aorto-iliac occlusive disease, there were more reinterventions and therefore surveillance should likely be more intense. The Covered Endovascular Reconstruction of the Aortic Bifurcation (CERAB) reconstruction was designed to improve outcomes of endovascular treatment of extensive aorto-iliac occlusive disease. At 5-year follow-up clinical improvement was found in 97.9% of patients without major amputations. The 5-year overall primary, primary-assisted, and secondary patency rates were 77.5%, 88.1%, and 95.0%, respectively, with a freedom-from clinically driven target lesion revascularization rate of 84.4%. Significantly better patency rates were observed for patients that were never treated before in the target area. The data implicate that CERAB are a valid treatment option for patients with extensive aorto-iliac occlusive disease. For patients previously treated in the target area, other treatment options might be considered, or more intensive follow-up surveillance is warranted.

Comparative effectiveness of bovine carotid artery xenograft and polytetrafluoroethylene in hemodialysis access revision.

When hemodialysis arteriovenous accesses fail, autogenous options are often limited. Non-autogenous conduit choices include bovine carotid artery xenografts (BCAG) and expanded polytetrafluoroethylene (PTFE), yet their comparative effectiveness in hemodialysis access revision remains largely unknown. A cohort study was performed from a prospectively collected institutional database from August 2010 to July 2021. All patients undergoing an arteriovenous access revision with either BCAG or PTFE were followed for up to 3 years from their index access revision. Revision was defined as graft placement to address a specific problem of an existing arteriovenous access while maintaining one or more of the key components of the original access (e.g. inflow, outflow, and cannulation zone). Outcomes were measured starting at the date of the index revision procedure. The primary outcome was loss of secondary patency at 3 years. Secondary outcomes included loss of post-intervention primary patency, rates of recurrent interventions, and 30-day complications. Pooled logistic regression was used to estimate inverse probability weighted marginal structural models for the time-to-event outcomes of interest. A total of 159 patients were included in the study, and 58% received access revision with BCAG. Common indications for revision included worn out cannulation zones (32%), thrombosis (18%), outflow augmentation (16%), and inflow augmentation (13%). Estimated risk of secondary patency loss at 3 years was lower in the BCAG group (8.6%, 3.9-15.1) compared to the PTFE group (24.8%, 12.4-38.7). Patients receiving BCAG experienced a 60% decreased relative risk of secondary patency loss at 3 years (risk ratio 0.40, 0.14-0.86). Recurrent interventions occurred at similar rates in the BCAG and PTFE groups, with 1.86 (1.31-2.43) and 1.60 (1.07-2.14) interventions at 1 year, respectively (hazard ratio 1.22, 0.74-1.96). Under the conditions of this contemporary cohort study, use of BCAG in upper extremity hemodialysis access revision decreased access abandonment when compared to PTFE.

High-Risk Characteristics for Clinical Failure after Isolated Femoropopliteal Peripheral Vascular Interventions

Recent studies suggesting increased late mortality with paclitaxel-coated devices (PCD) in femoropopliteal peripheral vascular interventions (PVI) prompted the U.S. Food and Drug Administration to recommend limiting the use of PCDs to "patients at particularly high-risk for restenosis". This study's aim is to characterize patients at high-risk for restenosis, and develop a risk score to guide clinicians in selecting patients for treatment with PCDs. Patients who underwent isolated femoropopliteal PVI for claudication or rest pain from 2016-2019 in the Vascular Quality Initiative were included. Patients who received intervention with a PCD, hybrid procedures, died within one year, or had missing follow up data were excluded. The primary endpoint was clinical failure at one year defined as > 50% restenosis, loss of patency, reintervention, or major amputation. Data was split randomly into 2/3 for development and 1/3 for validation. A parsimonious multivariable hierarchical logistic regression for clinical failure was developed and a risk score was created using beta-coefficients. The risk score was applied to the validation dataset and tested for goodness of fit and discrimination. Among 4,856 treated patients, 718 (14.8%) experienced clinical failure within one year. Clinical failure was associated with age ≤ 50, female sex (48.1% vs 39.5%), insulin-dependent diabetes (29.9% vs 23.1%), creatinine >2.0 mg/dL (9.9% vs 5.7%), prior ipsilateral lower extremity revascularization (48.5% vs 38.5%), prior ipsilateral minor amputation (5.3% vs 1.7%), rest pain vs claudication (30.8% vs 18.7%), occlusion length ≥ 20 cm (18.8% vs 15.0%), and Trans-Atlantic Inter-Society Consensus (TASC) II Classification C or D (40.4% vs 28.0%), all P ≤ 0.01. Risk score development was performed using a multivariable regression. The model demonstrated good fit and discrimination (C-statistic 0.71 in development and 0.72 in validation dataset). Predicted clinical failure was 8.9% for standard-risk (45.9% of interventions), 15.5% for high-risk (44.2% of interventions), and 33.8% for very high-risk patients (9.8% of interventions). A novel risk score was created with good discrimination for identifying patients at high-risk for clinical failure at one year after femoropopliteal PVI for claudication and rest pain. Patients at high-risk and very high-risk for clinical failure may benefit from alternative strategies including PCDs.

Two-year target vessel-related outcomes following use of off-the-shelf branched endografts for the treatment of thoracoabdominal aortic aneurysms

ObjectiveThe aim of this study was to assess clinical outcomes and target vessel patency through 2 years following thoracoabdominal aortic aneurysms (TAAA) repair with the off-the-shelf Zenith t-Branch Thoracoabdominal Endovascular Graft (William Cook Europe). MethodsThis post-market observational study was conducted at three European sites with ambispective enrollment from 2012 to 2017. Patients underwent endovascular TAAA repair with the t-Branch graft and bridging stent grafts (BSGs) for the celiac (CA), superior mesenteric (SMA), left renal (LRA), and/or right renal (RRA) arteries. Follow-up was through 2 years, per sites’ standard of care. Procedural and 1-year results were reported previously. ResultsEighty patients (mean age, 71.0±7.4 years; 70.0% men) were enrolled; six patients had symptomatic TAAAs, and 15 patients had contained ruptures. Technical success was achieved in 98.8% of patients (79/80). Median follow-up was 22.2 months (interquartile range, 9.2-25.1 months). At 24 months, Kaplan-Meier (KM) freedom from all-cause and aneurysm-related mortality were 78.5% and 98.6%, respectively. Beyond 12 months, 38 adverse events occurred in 20 patients, including two aortic ruptures (one study aneurysm and one non-study aneurysm) and six deaths (none aneurysm-related, as reported by the site). Compared with postprocedure, maximum aneurysm diameter decreased (>5 mm) in 84.6% (44/52), remained unchanged in 3.8% (2/52), and increased (>5 mm) in 11.5% (6/52) of patients with imaging follow-up after 12 months. No conversions to open repair, and no t-Branch graft or other endograft component migration or integrity issues were reported. No loss of patency was reported in the t-Branch or iliac limb grafts throughout the study. Throughout study duration, four patients had five imaging-reported BSG compressions, none of which required secondary intervention. KM freedom from secondary intervention was 76.3% at 24 months. Fourteen target vessel-related secondary interventions were performed, primarily consisting of stent placement for endoleak, stenosis, or occlusion. KM freedom from loss of primary patency was 94.8%, 100%, 91.3%, and 89.3% for the CA, SMA, LRA, and RRA, respectively, at 24 months. KM freedom from loss of secondary patency in the CA, SMA, LRA, and RRA were 96.3%, 100%, 98.2%, and 98.3% at 24 months, respectively. A total of 298 vessels were targeted, of which 12 were occluded over the study period. ConclusionsPrimary and secondary target vessel patency rates through 2 years demonstrated durable repair with the t-Branch graft in patients treated for symptomatic or asymptomatic thoracoabdominal aortic aneurysms.

Comparison of Clinical Outcomes in Patients Undergoing Common Femoral Thromboendarterectomy With or Without Patch Angioplasty

Surgical thrombo-endarterectomy (TEA) is the standard treatment for an occlusive lesion of the common femoral artery (CFA). However, there is limited knowledge on the need for patch angioplasty in CFA TEA. The objective of this study was to compare the peri-operative and two year results of CFA TEA with or without patch angioplasty. A multicentre retrospective observational study was performed at 34 Japanese centres. Comparisons were made between patients undergoing CFA TEA with or without patch angioplasty after propensity score matching (PSM). The primary endpoints were primary patency and freedom from target lesion revascularisation (TLR) of the TEA lesion. The secondary endpoints were hospital outcomes, limb salvage, and overall survival. Between 2018 and 2020, 428 TEA procedures (237 with patch angioplasty and 191 with primary closure) were performed. PSM extracted 151 pairs with no significant intergroup differences in baseline characteristics. Peri-operative death and complications occurred in 0.7% vs. 1.3% (p = 1.0) and 6.0% vs. 6.6% (p = 1.0), respectively. The follow up rate was 96% in a median follow up period of 14.9 months (interquartile range 8.3, 24.3). Loss of primary patency occurred in 18 patients. The two year primary patency of patch angioplasty cases was statistically significantly higher than that of primary closure cases (97.0% vs. 89.9%; p = .021). TLR was performed in 14 patients. The two year freedom from TLR in patch angioplasty cases was also statistically significantly higher than that in primary closure cases (98.6% vs. 92.9%; p = .003). During follow up, seven limbs required major amputation and 40 patients died. There was no statistically significant difference in limb salvage and survival between the two groups after PSM. This is the first report to show that patch angioplasty may decrease restenosis and target lesion revascularisation of CFA TEA lesions.

Long-term follow up of surgical management of blood blister-like aneurysms at non-branching sites of the internal carotid artery.

To describe long-term follow-up of 25 patients who presented with subarachnoid hemorrhages due to blood blister-like aneurysms (BBAs) treated with direct clipping or clip reinforcement with or without direct neck repair. Between June 1993 and July 2009, 25 consecutive patients with ruptured BBAs of the supraclinoid internal carotid artery were retrospectively reviewed. The mean age of patients was 39.5 ± 11.3 years. The mean duration of clinical follow-up was 128.9 months (range, 85-196 months). All aneurysms were located in the supraclinoid portion of the internal carotid artery. The mean aneurysm diameter was 4.04 ± 1.3 mm on intra-operative microscopic field. Tearing of the aneurysmal neck during dissection occurred in 8 (32%) patients. Six of 7 patients with neck tearing underwent direct neck repair. Surgeons treated aneurysms via direct clipping with a Bemsheet® in 5 (20%) patients or by clip reinforcement with a silicone sheet in 20 (80%) patients. Clinical outcomes were favorable (modified Rankin Scale [mRS]: 0-2) in 21 (84%) of 25 patients. Four (16%) patients had an unfavorable outcome (mRS: 3-6). The patient with severe disability (mRS: 4) was treated with clip reinforcement and direct neck repair. Mild stenosis, moderate stenosis, and total occlusion of the parent artery were confirmed in 10 (40%) patients, 6 (24%) patients, and 1 (4%) patient, respectively. Although surgical treatment of BBAs was associated with varying degrees of parent vessel patency loss, long-term follow-up results for more than 10 years showed that direct surgical clipping or clip reinforcement with a silicone sheet appeared to be a curative surgery.

Contemporary outcomes for branch renal artery repair

BackgroundThe purpose of this study was to provide an updated description of demographics, technical details, and clinical outcomes of 101 consecutive branch renal artery repairs in 98 patients using cold perfusion. MethodsA single-institution, retrospective analysis branch renal artery reconstructions was performed between 1987 and 2019. ResultsPatients were predominantly Caucasian (80.6%) women (74.5%) with a mean age of 46.8 ± 15.3 years. The mean preoperative systolic and diastolic blood pressures were 170.4 ± 33.0 mm Hg and 99.2 ± 19.9 mm Hg, respectively, requiring a mean of 1.6 ± 1.1 antihypertensive medications. The estimated glomerular filtration rate was 84.0 ± 25.3 mL/min. Most patients (90.2%) were not diabetic and never smokers (68%). Treated pathology included aneurysm (87.4%) and stenosis (23.3%) with histology demonstrating fibromuscular dysplasia (44.4%), dissection (5.1%), and degenerative not otherwise specified (50.5%). The right renal arteries were most frequently treated (44.2%), with a mean of 3.1 ± 1.5 branches involved. Reconstruction was accomplished using bypass in 90.3% of cases using aortic inflow in 92.7% and a saphenous vein conduit in 92%. Branch vessels served as outflow in 96.9% and syndactylization of branches was used to decrease the number of distal anastomoses in 45.3% of repairs. The mean number of distal anastomoses was 1.5 ± 0.9. Postoperatively, the mean systolic blood pressure improved to 137.9 ± 20.8 mm Hg (mean decrease of 30.5 ± 32.8 mm Hg; P < .0001) and the mean diastolic blood pressure improved to 78.4 ± 12.7 mm Hg (mean decrease of 20.1 ± 20.7 mm Hg; P < .0001) with patients requiring a mean of 1.4 ± 1.0 antihypertensive medications (mean decrease of 0.2 ±1.0 medications; P = .048). The postoperative estimated glomerular filtration rate was 89.1 mL/min (mean increase of 4.1 mL/min; P = .08). The mean length of stay was 9.0 ± 5.8 days and 96.1% of patients were discharged home. The mortality rate was 1% (one patient with liver failure) and the major morbidity rate was 15%. There were five infectious complications (pneumonia, Clostridium difficile, and wound infection) and five patients required return to the operating room (one for nephrectomy, one for bleeding, two for thrombosis, and one for second trimester pregnancy loss requiring dilation and curettage and splenectomy). One patient required temporary dialysis owing to graft thrombosis. Two patients developed arrhythmias. No patients suffered a myocardial infarction, stroke, or limb loss. After 30 days, follow-up data were available for 82 bypasses. At this time, three reconstructions were no longer patent. Intervention was required to retain patency for five bypasses. After 1 year, patency data were available for 61 bypasses and five were no longer patent. Of the five grafts with loss of patency, two underwent intervention in attempt to maintain patency, which subsequently failed. ConclusionsRepair of renal artery pathology involving the branches can be performed with short- and long-term technical success and significant prospect of decreasing an elevated blood pressure. The operations required to fully address the presenting pathology are often quite complex involving multiple distal anastomoses and consolidation of small secondary branches. The procedure carries a small but significant risk of major morbidity and mortality.

Asian race is associated with peripheral arterial disease severity and postoperative outcomes

ObjectiveThe nature of peripheral arterial disease and postoperative outcomes are understudied in Asian patients. We aimed to determine if there are disparities in disease severity at the time of presentation and postoperative outcomes with regard to Asian race. MethodsWe analyzed the Society for Vascular Surgery Vascular Quality Initiative Peripheral Vascular Intervention dataset from 2017 to 2021, which includes endovascular lower extremity interventions. Propensity scores were used to match White and Asian patients based on age, sex, comorbidities, ambulatory/functional status, and intervention level. Differences were examined with regard to Asian race across all patients in the United States, Canada, and Singapore, and separately in the United States and Canada only. The primary outcome was emergent intervention. We also examined differences in severity of disease and postoperative outcomes. ResultsA total of 80,312 White and 1689 Asian patients underwent peripheral vascular intervention. After propensity score matching, we identified 1669 matched pairs of patients across all centers including Singapore and 1072 matched pairs in the United States and Canada only. Among the matched cohort consisting of all centers, Asian patients had a higher rate of emergent intervention to prevent limb loss (5.6% vs 1.7%, P < .001). The majority of Asian patients presented with chronic limb threatening ischemia at a higher rate than White patients within the cohort including Singapore (71% vs 66%, P = .005). Within both propensity-matched cohorts, the rate of in-hospital death was higher in Asian patients (all centers: 3.1% vs 1.2%, P < .001; United States and Canada only: 2.1% vs 0.8%, P = .010). Logistic regression demonstrated greater odds of emergent intervention in Asian patients from all centers including Singapore (odds ratio [OR], 3.3; 95% confidence interval [CI], 2.2-5.1, P < .001) but not in the United States and Canada only (OR, 1.4; 95% CI, 0.8-2.8, P = .261). In addition, Asian patients had greater odds of in-hospital death in both matched cohorts (all centers: OR, 2.6; 95% CI, 1.5-4.4, P < .001; United States and Canada: OR, 2.5; 95% CI, 1.1-5.8, P = .026). Asian race was associated with a greater risk of loss of primary patency at 18 months (all centers: hazard ratio, 1.5; CI, 1.2-1.8, P = .001; United States and Canada only: hazard ratio, 1.5; CI, 1.2-1.9, P = .002). ConclusionsAsian patients are more likely to present with advanced peripheral arterial disease and undergo emergent intervention to prevent limb loss, in addition to having worse postoperative outcomes and long-term patency. These results highlight the need for improved screening and postoperative follow-up in this understudied population.

Tracheostomy in Non-malignant Disorders

Background: Tracheostomy is a surgical procedure, often a life saving measure in a variety of clinical conditions. It is one of the commonest procedures carried out on the critically ill patient. The most common causes of non-malignant airway obstruction are head and severe facial trauma, cerebrovascular accident, coma, respiratory burn and presence of foreign bodies in airway etc. Tracheostomy is an increasingly utilised adjunct in the ICU management of patients. Effective tracheostomy management involved the multi-professional team in a coordinated approach.&#x0D; Objectives: To study the indications of tracheostomy in non-malignant disorders.&#x0D; Study design: Cross-sectional study.&#x0D; Study setting and period: Department of Otolaryngorhinology and Head- Neck surgery (Unit- 1,2,3), General Surgery, ICU, Casualty, Neurosurgery, Thoracic surgery, Burn &amp; Plastic Surgery and relevant OPD in Dhaka Medical College Hospitalfrom6th September 2015 to 5th March 2016.&#x0D; Methods: A hospital based cross-sectional study. Fifty patients admitted to hospital, underwent tracheostomy for non-malignant factors. Purposive samplings technique was used. Detail demographic data were collected from the informant and recorded in structured case record form. Clinical examination and relevant investigation were done meticulously. All collected questionnaire checked very carefully to identify the error in the data. Data processing work consist of registration schedules, editing computerization, preparation of dummy table, analyzing and matching of data.&#x0D; Result: A total of 50 patients of non-malignant pathology causing airway patency loss in different ward unit of DMCH were selected. In this study, maximum numbers of patients (36%) were between 51-70 years age groups with mean age was 47.23±11.57 years. It was observed that, frequency of non-malignant aetiology for tracheostomy gradually increases with age. Study show that, 51-70 years was most frequent age group (36%). Out of 50 cases 82% were male. Present study show that socioeconomically majority patients were poor class (52%), highest percentage of patient comprised of day labourer (30%). Head trauma (12%) and cerebrovascular accidents (9%) were the most common etiological factor trauma was the major aetilogical group (50%),followed by, central drive problems or neurological disease (38%) and elective tracheostomy was done.&#x0D; Conclusion: Head and facial trauma, cerebrovascular accident, coma, respiratory burn and presence of foreign bodies etc. are common aetilogical factors. It was found that tracheostomy is safer alternative to intubation when a prolonged artificial airway is required.&#x0D; Bangladesh J Otorhinolaryngol 2022; 28(2): 157-164

Comparative 2-year outcomes of the Misago stent versus other self-expandable nitinol stents for the endovascular treatment of aortoiliac disease.

The Misago iliac stent has not been compared with other stents. This study aimed to evaluate the 2-year clinical outcomes between the Misago stent and other self-expandable nitinol stents for symptomatic chronic aortoiliac disease. This retrospective, single-center observational study enrolled 138 patients (180 limbs; Rutherford classification, between categories 2 and 6) treated with a Misago stent (N.=41) or self-expandable nitinol stent (N.=97) between January 2019 and December 2019. The primary endpoint was patency for up to 2 years. The secondary endpoints were technical success, procedure-related complications, freedom from target lesion revascularization, overall survival, and freedom from major adverse limb events. Multivariate Cox proportional hazards analysis was used to investigate predictors of restenosis. The mean follow-up duration was 710±201 days. The 2-year primary patency rate was comparable between the groups (Misago, 89.6% and self-expandable nitinol stent, 91.0%, P=0.883). The technical success rate was 100% in both groups, and procedure-related complications were equivalent between the groups (1.7% and 2.4%, respectively; P=0.773). Freedom from target lesion revascularization was not significantly different between the groups (97.6% and 94.4%, respectively; P=0.890). The overall survival rate and freedom from major adverse limb events were not significantly different between the groups (77.2% and 70.8%, respectively, P=0.209; 66.9% and 58.4%, respectively, P=0.149). Statin therapy was positively associated with primary patency. The Misago stent for aortoiliac lesions demonstrated comparable and acceptable clinical results of safety and efficacy for up to 2 years compared with other self-expandable stents. Statin use predicted the prevention of patency loss.

Comparing post-maturation outcomes of arteriovenous grafts and fistulae.

Though arteriovenous grafts (AVG) mature more reliably than arteriovenous fistulae (AVF) and require fewer maturation procedures (MP) to obtain functional patency, AVG are thought to have worse function after maturation. We explored differences in post-maturation outcomes between the following groups: AVF patients who did (AS-AVF) and did not (unAS-AVF) require assisted maturation and AVG patients who did (AS-AVG) and did not (unAS-AVG) require assisted maturation. Using the US Renal Data System (2012-2017), we retrospectively identified patients who initiated dialysis with a central venous catheter, underwent AVF or AVG placement and achieved successful two-needle cannulation. Primary patency and access abandonment after maturation were compared across groups using competing risks regression methods, generating sub-hazards ratios (sHR). We identified 42,664 AVF and 12,335 AVG that met inclusion criteria. A larger proportion of AVFs required interventions: 18,408 AVF (43.2%) versus 2594 AVG (21.0%; p < 0.01). Both AS-AVG and AS-AVF patients experienced patency loss at 1 year more frequently compared with unAS-AVG (67.5% & 57.5% vs 55.2% respectively). Patency loss was lowest in unAS-AVF (38.9%). These trends were robust on adjusted analysis (unAS-AVG reference, AS-AVG sHR = 1.44, p < 0.01; AS-AVF sHR = 1.08, p < 0.01, unAS-AVF sHR = 0.67, p < 0.01). AS-AVGs were more likely to be abandoned than unAS-AVGs (11.7% unAS-AVG vs 17.2% AS-AVG). Fistulae, assisted or not, had lower unadjusted rates of 1-year abandonment than grafts (8.9% AS-AVF vs 7.3% unAS-AVF). On adjusted analysis, AVF usage was protective against abandonment (unAS-AVG, reference; AS-AVF sHR = 0.67, p < 0.01; unAS-AVF sHR = 0.59, p < 0.01) while AS-AVG was not (AS-AVG sHR = 1.32, p < 0.01). unAS-AVF have the best long-term outcomes. AS-AVF lose primary patency at a higher rate than unAS-AVG. AVGs may be a better choice than AVFs if veins are marginal and likely to require assisted maturation. Further research is needed to identify anatomic and physiologic factors that affect long-term performance and influence conduit choice.

Hypogastric artery luminal diameter predicts common-external iliac stent patency and major adverse limb events in patients with aortoiliac occlusive disease.

Hypogastric coverage may be required for occlusive disease at the iliac arterial bifurcation. In this study, we sought to determine patency rates of common-external iliac artery (C-EIA) bare metal stents (BMS) spanning the hypogastric origin in patients with aortoiliac occlusive disease (AIOD). In addition, we sought to identify predictors of C-EIA BMS patency loss and major adverse limb events (MALE) in patients requiring hypogastric coverage. We hypothesized that worsening stenosis of the hypogastric origin would negatively influence C-EIA stent patency and freedom from MALE. This is a single center, retrospective review of consecutive patients undergoing elective, endovascular treatment of aortoiliac disease (AIOD) between 2010 and 2018. Only patients with C-EIA BMS coverage of a patent IIA origin were included in the study. Hypogastric luminal diameter was determined from preoperative CT angiography. Analysis was performed using Kaplan-Meier survival analysis, univariable and multivariable logistic regression, and receiver operator characteristics (ROC). There were 236 patients (318 limbs) who were included in the study. AIOD was TASC C/D in 236/318 (74.2%) of cases. C-EIA stent primary patency was 86.5% (95% confidence interval: 81.1, 91.9) at 2years and 79.7% (72.8, 86.7) at 4years. Freedom from ipsilateral MALE was 77.0% (71.1, 82.9) at 2years and 68.7% (61.3, 76.2) at 4years. Luminal diameter of the hypogastric origin was most strongly associated with loss of C-EIA BMS primary patency in multivariable analysis (hazard ratio: 0.81, p = .02). Insulin-dependent diabetes, Rutherford's class IV or above, and stenosis of the hypogastric origin were significantly predictive of MALE in both univariable and multivariable analyses. In ROC analysis, luminal diameter of the hypogastric origin was superior to chance in prediction of C-EIA primary patency loss and MALE. Hypogastric diameter >4.5mm had a negative predictive value of 0.94 for C-EIA primary patency loss and 0.83 for MALE. Patency rates of C-EIA BMS are high. Hypogastric luminal diameter is an important and potentially modifiable predictor of C-EIA BMS patency and MALE in patients with AIOD.

Comparing the impact of the loss of patency between treatment with drug-coated balloon angioplasty and drug-eluting stent placement

ObjectiveTo compare the results of endovascular treatment with drug-eluting stents (DES) and drug-coated balloons (DCB) in atherosclerotic lesions in the femoropopliteal artery, as well as to assess restenotic patterns. MethodsClinical data from 617 cases treated with DES or DCB for femoropopliteal diseases were analyzed in this multicenter, retrospective cohort study. From these, 290 DES and 145 DCB cases were extracted by propensity score matching. Outcomes investigated were 1- and 2-year primary patency, reintervention, and restenotic pattern and its impact on symptoms in each group. ResultsThe primary patency rates at 1 and 2 years in the DES group were superior to those in the DCB group (84.8% and 71.1% vs 81.3% and 66.6%, P = .043), whereas there was no significant difference in freedom from target lesion revascularization (91.6% and 82.6% vs 88.3% and 78.8%, P = .13). Compared with what was measured before the index procedures, exacerbated symptoms, rate of occlusion, and an increase in the occluded length at loss of patency were more frequent in the DES group than in the DCB group. The odds ratios were 3.53 (95% confidence interval, 1.31-9.49; P = .012), 3.61 (1.09-11.9; P = .036), and 3.82 (1.15-12.7; P = .029), respectively. On the other hand, the frequency of an increase in lesion length and requirement of target lesion revascularization were similar between the two groups. ConclusionsPrimary patency was significantly higher at 1 and 2 years in the DES than in the DCB group. However, DES were associated with exacerbated clinical symptoms and complicated lesion characteristics at the point of loss of patency.