The Obesity Paradox Exists for Perioperative Complications and Mortality Following Lower Extremity Arterial Bypass Surgery

OBJECTIVE

The obesity paradox refers to a phenomenon by which obese individuals experience lower risk of mortality and even protective associations from chronic disease sequelae when compared to the non-obese and underweight population. Prior literature has demonstrated an obesity paradox after cardiac and other surgical procedures. However, the relationship between body mass index (BMI) and perioperative complications for patients undergoing major open lower extremity arterial revascularization is unclear.

METHODS

We queried the Vascular Quality Initiative (VQI) for individuals receiving unilateral infrainguinal bypass between 2003 and 2020. We used multivariable logistic regression to assess the relationship of BMI categories [underweight (<18.5), non-obese (18.5-24.9), Overweight (25-29.9), Class 1 obesity (30-34.9), Class 2 obesity (35-39.9) and Class 3 obesity (>40)] with 30-day mortality, surgical site infection (SSI) and adverse cardiovascular events. We adjusted the models for key patient demographics, comorbidities, technical and perioperative characteristics.

RESULTS

From 2003-2020, 60,588 arterial bypass procedures met inclusion criteria for analysis. Upon multivariable logistic regression with the non-obese category as reference group, odds of 30-day mortality were significantly decreased among the overweight [OR: 0.64, (95% CI: 0.53-0.78)], Class 1 obese [OR: 0.65, (95 % CI: 0.52-0.81)], Class 2 obese [OR: 0.66, (95 % CI: 0.48-0.90)] and Class 3 obese [OR: 0.61, (95 % CI: 0.39-0.97)] patient categories. Conversely, odds of 30-day mortality were increased in the underweight patient group [OR: 1.58, (95% CI: 1.16-2.13)]. Furthermore, a BMI-dependent positive association was present with odds of SSI with patients in Class 3 obesity having the highest odds [OR: 2.10, (95% CI: 1.60-2.76)]. Finally, among the adverse cardiovascular event outcomes assessed, only myocardial infarction (MI) demonstrated decreased odds among overweight [OR: 0.82, (95 % CI: 0.71-0.96)], Class 1 obese [OR: 0.78, (95 % CI: 0.65-0.93)] and Class 2 obese [OR: 0.66, (95 % CI: 0.51-0.86)] patient populations. Odds of MI among the underweight and Class 3 obesity groups were not significant.

CONCLUSIONS

The obesity paradox is evident in patients undergoing lower extremity bypass procedures, particularly with odds of 30-day mortality and myocardial infarction. Our findings suggest that having higher BMI (overweight and Class 1-3 obesity) is not associated with increased mortality and should not be interpreted as a contraindication for lower extremity arterial bypass surgery. However, these patients should be under vigilant surveillance for SSI. Finally, patients that are underweight have a significantly increased odds of 30-day mortality and may be more suitable candidates for endovascular therapy.

Long-term outcomes of carotid endarterectomy vs transfemoral carotid stenting in a Medicare-matched database

BACKGROUND

Carotid endarterectomy (CEA) is associated with lower risk of perioperative stroke compared with transfemoral carotid artery stenting (TFCAS) in the treatment of carotid artery stenosis. However, there is discrepancy in data regarding long-term outcomes. We aimed to compare long-term outcomes of CEA vs TFCAS using the Medicare-matched Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database.

METHODS

We assessed patients undergoing first-time CEA or TFCAS in Vascular Quality Initiative Vascular-Vascular Implant Surveillance and Interventional Outcomes Network from January 2003 to December 2018. Patients with prior history of carotid revascularization, nontransfemoral stenting, stenting performed without distal embolic protection, multiple or nonatherosclerotic lesions, or concomitant procedures were excluded. The primary outcome of interest was all-cause mortality, any stroke, and a combined end point of death or stroke. We additionally performed propensity score matching and stratification based on symptomatic status.

RESULTS

A total of 80,146 carotid revascularizations were performed, of which 72,615 were CEA and 7531 were TFCAS. CEA was associated with significantly lower risk of death (57.8% vs 70.4%, adjusted hazard ratio [aHR], 0.46; 95% confidence interval [CI], 0.41-0.52; P < .001), stroke (21.3% vs 26.6%; aHR, 0.63; 95% CI, 0.57-0.69; P < .001) and combined end point of death and stroke (65.3% vs 76.5%; HR, 0.49; 95% CI, 0.44-0.55; P < .001) at 10 years. These findings were reflected in the propensity-matched cohort (combined end point: 34.6% vs 46.8%; HR, 0.53; 95% CI, 0.46-0.62) at 4 years, as well as stratified analyses of combined end point by symptomatic status (asymptomatic: 63.2% vs 74.9%; HR, 0.49; 95% CI, 0.43-0.58; P < .001; symptomatic: 69.9% vs 78.3%; HR, 0.51; 95% CI, 0.45-0.59; P < .001) at 10 years.

CONCLUSIONS

In this analysis of North American real-world data, CEA was associated with greater long-term survival and fewer strokes compared with TFCAS. These findings support the continued use of CEA as the first-line revascularization procedure.

Propensity-Score Matched Analysis of Three Years Survival of Trans Carotid Artery Revascularization Versus Carotid Endarterectomy in the Vascular Quality Initiative Medicare-Linked Database

OBJECTIVE

Carotid endarterectomy (CEA) remains the gold standard procedure for carotid revascularization. Transfemoral carotid artery stenting (TFCAS) was introduced as a minimally invasive alternative procedure in patients who are at high risk for surgery. However, TFCAS was associated with an increased risk of stroke and death compared to CEA.

BACKGROUND

Transcarotid artery revascularization (TCAR) has outperformed TFCAS in several prior studies and has shown similar perioperative and 1-year outcomes compared with CEA. We aimed to compare the 1-year and 3-year outcomes of TCAR versus CEA in the Vascular Quality Initiative (VQI)-Medicare-Linked [Vascular Implant Surveillance and Interventional Outcomes Network (VISION)] database.

METHODS

The VISION database was queried for all patients undergoing CEA and TCAR between September 2016 to December 2019. The primary outcome was 1-year and 3-year survival. One-to-one propensity-score matching (PSM) without replacement was used to produce 2 well-matched cohorts. Kaplan-Meier estimates, and Cox regression was used for analyses. Exploratory analyses compared stroke rates using claims-based algorithms for comparison.

RESULTS

A total of 43,714 patients underwent CEA and 8089 patients underwent TCAR during the study period. Patients in the TCAR cohort were older and were more likely to have severe comorbidities. PSM produced two well-matched cohorts of 7351 pairs of TCAR and CEA. In the matched cohorts, there were no differences in 1-year death [hazard ratio (HR)=1.13; 95% CI, 0.99-1.30; P =0.065]. At 3-years, TCAR was associated with slight increased risk of death (HR=1.16; 95% CI, 1.04-1.30; P =0.008). When stratifying by initial symptomatic presentation, the increased 3-year death associated with TCAR persisted only in symptomatic patients (HR=1.33; 95% CI, 1.08-1.63; P =0.008). Exploratory analyses of postoperative stroke rates using administrative sources suggested that validated measures of claims-based stroke ascertainment are necessary.

CONCLUSIONS

In this large multi-institutional PSM analysis with robust Medicare-linked follow-up for survival analysis, the rate of death at 1 year was similar in TCAR and CEA regardless of symptomatic status. The slight increase in the risk of 3-year death in symptomatic patients undergoing TCAR is likely confounded by more severe comorbidities despite matching. A randomized controlled trial comparing TCAR to CEA is necessary to further determine the role of TCAR in standard-risk patients requiring carotid revascularization.

Two-Stage Offers No Advantages over Single-Stage Arteriovenous Creation: An Analysis of Multicenter National Data

BACKGROUND

Traditionally, arteriovenous fistulas (AVF) involving the basilic vein (BV) have been created in 1 or 2 stages to allow time for the vein to enlarge before superficialization for potential better fistula maturation. Previous single institution studies and meta-analyses have found conflicting outcomes between single-stage and 2-stage procedures. Our study aims to use a large national database to assess the difference in outcomes between single-stage and 2-stage procedures for dialysis access.

METHODS

We studied all patients undergoing BV AVF creation in the Vascular Quality Initiative (VQI) from 2011 to 2021. Patients were split into single-stage or a planned 2-stage procedure for dialysis access. Primary outcomes included dialysis use with index fistula, maturity rate, and number of days from surgery to fistula use. Secondary outcomes included patency (defined by physical exam or imaging on follow-up), 30-day mortality, and postoperative complications (bleeding, steal syndrome, thrombosis, or neuropathy). Logistic regression models were used to assess the association between staged dialysis access procedures and primary outcomes of interest.

RESULTS

The cohort consisted of 22,910 individuals of which 7,077 (30.9%) had a 2-staged dialysis access procedure and 15,833 (69.1%) had a single-staged procedure. Average follow-up was 345 days in the single stage and 420 days for 2-stage. Baseline characteristics were significantly different between the 2 groups in terms of medical comorbidities. Primary outcomes were significant for more patients in the 2-stage group undergoing dialysis with the index fistula compared to single stage (31.5% vs. 22.2%, P < 0.0001), significant decrease in days to use in current dialysis patients (103.9 days single stage versus 141.0 days 2-stage, P < 0.0001), and no difference in maturity at follow-up (19.3% single-stage and 17.4% 2-stage, P = 0.354). Secondary outcomes revealed no difference in 30-day mortality or patency (89.8% single-stage and 89.1% 2-stage, P = 0.383), but a significant difference in postoperative complications with a 2-stage procedure compared to 1-stage (1.6% vs. 1.1%, P = 0.026). Finally, a spline model was used to determine that a preoperative vein of 3 mm or less could be a cutoff in which a 2-stage procedure might be beneficial.

CONCLUSIONS

This study demonstrates that when dialysis access fistulas are created using the BV, there is no difference in maturity rate or 1-year patency when assessing single-stage versus 2-stage procedures. However, 2-stage procedures significantly delay the time of first use of the fistula and increase postoperative complications. Therefore, we suggest performing single stage procedures when the vein is of appropriate diameter to minimize multiple procedures, complications and expedite time to maturity.

Renin-Angiotensin-Aldosterone System Inhibitors Are Associated With Favorable Outcomes Compared to Beta Blockers in Reducing Mortality Following Abdominal Aneurysm Repair

Background The best medical therapy to control hypertension following abdominal aortic aneurysm repair is yet to be determined. We therefore examined whether treatment with renin-angiotensin-aldosterone system inhibitors (RAASIs) versus beta blockers influenced postoperative and 1-year clinical end points following abdominal aortic aneurysm repair in a Medicare-linked database. Methods and Results All patients with hypertension undergoing endovascular aneurysm repair and open aneurysm repair in the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database between 2003 and 2018 were included. Patients were divided into 2 groups based on their preoperative and discharge medications, either RAASIs or beta blockers. Our cohort included 8789 patients, of whom 3523 (40.1%) were on RAASIs, and 5266 (59.9%) were on beta blockers. After propensity score matching, there were 3053 matched pairs of patients in each group. After matching, RAASI use was associated with lower risk of postoperative mortality (odds ratio [OR], 0.3 [95% CI, 0.1-0.6]), myocardial infarction (OR, 0.1 [95% CI, 0.03-0.6]), and nonhome discharge (OR, 0.6 [95% CI, 0.5-0.7]). Before propensity score matching, RAASI use was associated with lower 1-year mortality (hazard ratio [HR], 0.4 [95% CI, 0.4-0.5]) and lower risk of aneurysmal rupture (HR, 0.7 [95% CI, 0.5-0.9]). These results persisted after propensity score matching for mortality (HR, 0.4 [95% CI, 0.4-0.5]) and aneurysmal rupture (HR, 0.7 [95% CI, 0.5-0.9]). Conclusions In this large contemporary retrospective cohort study, RAASI use was associated with favorable postoperative outcomes compared with beta blockers. It was also associated with lower mortality and aneurysmal rupture at 1 year of follow-up.

Hemodynamic Instability Predicts In-Hospital and One-Year Mortality After TransCarotid Artery Revascularization and TransFemoral Carotid Stenting

OBJECTIVES

Blood pressure fluctuations are a common hemodynamic alteration following carotid artery stenting either with transfemoral (TFCAS) or transcarotid (TCAR) approach and are thought to be related to alteration in baroreceptor function due to angioplasty and stent expansion. These fluctuations are particularly worrisome in the high-risk patient population referred for CAS. This study aims to evaluate the outcomes of patients who required the administration of intravenous blood pressure medication (IVBPmed) for hypotension or hypertension after CAS.

METHODS

All patients undergoing carotid revascularization in the Vascular Quality Initiative (VQI) database between 2016-2021 were included. we compared outcomes of patients who required postoperative IVBPmed to treat hyper- or hypotension with normotensive patients. In-hospital outcomes were compared using multivariable logistic regression. One-year outcomes were assessed using Kaplan-Meier survival and multivariable Cox proportional hazard regression analyses.

RESULTS

We identified 38,510 patients undergoing CAS (57.7% TCAR and 42.3% TFCAS), of which, 30% received IVBPmed for treatment of either postoperative hypertension (12.6%) or hypotension (16.4%). In multivariable analysis, postoperative hypotension was associated with a higher risk of stroke, death, or MI (OR: 3.1, 95%CI (2.6-3.6), P<.001), stroke or death (OR: 2.9, 95%CI (2.4-3.5), P<.001), stroke (OR: 2.6, 95%CI (2.1-3.2), P<.001), death (OR: 3.5, 95%CI (2.6-4.8), P<.001), MI (OR: 4.7, 95%CI (3.3-6.7), P<.001), and bleeding (OR: 1.96, 95%CI (1.4-2.7), P<.001) compared to normotensive patients. Postoperative hypertension was associated with a higher risk of stroke, death, or MI (3.6, 95%CI (3-4.4), P<.001), stroke or death (OR: 3.3, 95%CI (2.7-4.1), P<.001), stroke (OR: 3.7, 95%CI (3-4.7), P<.001), death (OR: 2.7, 95%CI (1.9-3.9), P<.001), MI (OR: 5.7, 95%CI (3.9-8.3), P<.001), and bleeding (OR: 1.9, 95%CI (1.4-2.7), P<.001) compared to normotensive patients.

CONCLUSIONS

Postoperative hypertension or hypotension requiring IVBPmed after CAS is associated with an increased risk of in-hospital stroke, death, MI, and bleeding. Postoperative hypertension is associated with worse survival at one year. This study indicates that the need for IVBPmed after CAS is not benign, therefore, these patients necessitate aggressive perioperative medical management and safe techniques to avoid hypo and hypertension. Close follow-up and continue medical management is needed to maximize these patients' survival.

Novel Risk Score Calculator for Perioperative Mortality after EVAR with Incorporation of Anatomical Factors

BACKGROUND

Hostile proximal aortic neck anatomy has been associated with an increased risk of perioperative mortality after endovascular aneurysm repair (EVAR). However, all available mortality risk prediction models after EVAR lack neck anatomic associations. The aim of this study is to develop a preoperative prediction model for perioperative mortality after EVAR incorporating important anatomic factors.

METHODS

Data were obtained from the Vascular Quality Initiative database on all patients who underwent elective EVAR between January 2015 and December 2018. A stepwise multivariable logistic regression analysis was implemented to identify independent predictors and develop a risk calculator for perioperative mortality after EVAR. Internal validation was done using bootstrap of 1,000 reps.

RESULTS

A total of 25,133 patients were included, of whom 1.1% (N = 271) died within 30 days or before discharge. Significant preoperative predictors of perioperative mortality were age (odds ratio [OR], 1.053; 95% confidence interval [CI], 1.050-1.056; P < 0.001), female sex (OR, 1.46; 95% CI, 1.38-1.54; P < 0.001), chronic kidney disease (OR, 1.65; 95% CI, 1.57-1.73; P < 0.001), chronic obstructive pulmonary disease (OR, 1.86; 95% CI, 1.77-1.94; P < 0.001), congestive heart failure (OR, 2.02; 95% CI, 1.91-2.13, P < 0.001), aneurysm diameter ≥ 6.5 cm (OR, 2.35; 95% CI, 2.24-2.47, P < 0.001), proximal neck length < 10 mm (OR, 1.96; 95% CI, 1.81-2.12; P < 0.001), proximal neck diameter ≥ 30 mm (OR, 1.41; 95% CI, 1.32-1.5; P < 0.001), infrarenal neck angulation ≥ 60° (OR, 1.27; 95% CI, 1.18-1.26; P < 0.001), and suprarenal neck angulation ≥ 60° (OR, 1.26; 95% CI, 1.16-1.37; P < 0.001). Significant protective factors included aspirin use (OR, 0.89; 95% CI, 0.85-0.93; P < 0.001) and statin intake (OR, 0.77; 95% CI, 0.73-0.81; P < 0.001). These predictors were incorporated to build an interactive risk calculator of perioperative mortality after EVAR (C-statistic = 0.749).

CONCLUSIONS

This study provides a prediction model for mortality following EVAR that incorporates aortic neck features. The risk calculator can be used to weigh risk/benefit ratio when counseling patients preoperatively. Prospective use of this risk calculator may show its benefit in long-term prediction of adverse outcomes.

Loss of follow-up after carotid revascularization is associated with worse long-term stroke and death

OBJECTIVES

Society for Vascular Surgery practice guidelines recommend surveillance with duplex ultrasound scanning at baseline (within 3 months from discharge), every 6 months for 2 years, and annually afterward following carotid endarterectomy or carotid artery stenting. There is a growing concern regarding the significance of postoperative follow-up after several vascular procedures. We sought to determine whether 1-year loss to follow-up (LTF) after carotid revascularization was associated with worse outcomes in the Vascular Quality Initiative (VQI) linked to Vascular Implant Surveillance and Interventional Outcomes Network (VISION) database.

METHODS

All patients who underwent carotid revascularization in the VQI VISION database between 2003 and 2016 were included. LTF was defined as failure to complete 1-year follow-up in the VQI long-term follow-up dataset. Data about stroke and mortality were captured in the VISION dataset using a list of Current Procedural Terminology, International Classification of Diseases (Ninth Revision), and International Classification of Diseases (Tenth Revision) codes linked to index procedures in VQI. Kaplan-Meier life-table methods and Cox proportional hazard modeling were used to compare 5- and 10-year outcomes between patients with no LTF and those who were LTF.

RESULTS

A total of 58,840 patients were available for analysis. The 1-year LTF rate was 43.8%. Patients who were LTF were older and more frequently symptomatic, with chronic obstructive pulmonary diseases, chronic kidney diseases, and congestive heart failure. Also, patients who underwent carotid artery stenting were more likely to be LTF compared with carotid endarterectomy patients (54.5% vs 42.3%; P < .001). The incidence of postoperative (30 days) stroke was higher in the LTF group (2.9% vs 1.7%; P < .001). Cox regression analysis revealed that LTF was associated with an increased risk of long-term stroke at 5 years (hazard ratio [HR]: 1.4, 95% confidence interval [CI]: 1.2-1.6; P < .001) and 10 years (HR: 1.3, 95% CI: 1.2-1.5; P < .001). It was also associated with significantly higher mortality at 5 years (HR: 2.5, 95% CI: 2.3-2.8; P < .001) and 10 years (HR: 2.2, 95% CI: 1.9-2.5; P < .001). Stroke or death was significantly worse in the LTF group at 5 years (HR: 2.3, 95% CI: 2.1-2.5; P < .001) and up to 10 years (HR: 2.02, 95% CI: 1.8-2.3; P < .001).

CONCLUSIONS

One-year follow-up after carotid revascularization procedures was found to be associated with better stroke- and mortality-free survival. Surgeons should emphasize the importance of follow-up to all patients who undergo carotid revascularization, especially those with multiple comorbidities and postoperative neurological complications.

TransCarotid Artery Revascularization Can Be Safely Performed in Patients Undergoing Dialysis

BACKGROUND

TransCarotid Artery Revascularization (TCAR) has been effectively performed to prevent stroke in patients with carotid artery stenosis (CS). Prior studies established that TCAR can be safely performed in high-risk patients such as octogenarians, patients with prior carotid endarterectomy (CEA), contralateral occlusion, and heavily calcified lesions. Hemodialysis patients are at an increased risk of exhibiting cardiovascular complications. This study aims to investigate how dialysis may affect TCAR outcomes.

METHODS

The Vascular Quality Initiative (VQI) dataset was queried for patients undergoing TCAR from November 2016 to November 2021. Patients were divided into dialysis and nondialysis groups. The primary outcome was the composite endpoint of in-hospital stroke, death, or myocardial infarction (MI). Secondary outcomes were in-hospital stroke, stroke, or transient ischemic attack (TIA), death, prolonged length of stay (more than 1 day) (PLOS), MI, and stroke or death. Multivariable logistic regression analysis was used to assess in-hospital outcomes. Kaplan-Meier survival and log-rank test were used to assess 1-year survival.

RESULTS

A total of 22,619 patients underwent TCAR during the study period. Of these, 327 patients were undergoing dialysis. On univariable analysis, dialysis patients were associated with a higher risk of mortality compared to nondialysis patients (1.2% vs. 0.6%, P = 0.030). However, after adjusting for potential confounders, this difference did not persist (odd ratio [OR]: 1.99, 95% confidence interval [CI] (0.8-4.9), P = 0.136). Dialysis patients were more likely to experience PLOS (OR: 1.6, 95% CI (1.2-2), P < 0.001). There was no difference between dialysis and nondialysis patients in the risk of stroke or death, stroke, stroke or TIA, MI, and stroke or death, or MI on univariable and multivariable analyses. At 1 year, the overall survival for dialysis versus nondialysis patients was 81.5% vs. 95.5%, P < 0.001.

CONCLUSIONS

To our knowledge, this is the first study to date of dialysis patients who have undergone TCAR. We have shown that there was no difference in the risk of stroke, death, and MI between dialysis and nondialysis patients. Therefore, TCAR can be safely offered to patients undergoing dialysis. Future studies with larger number of patients are warranted to confirm these results.

Dual Antiplatelet Therapy Is Associated with Increased Risk of Bleeding and Decreased Risk of Stroke Following Carotid Endarterectomy

BACKGROUND

Despite many patients undergoing carotid endarterectomy (CEA) being on dual antiplatelet therapy (DAPT) for cardiac or neurologic indications, the impact of such therapy on perioperative outcomes remains unclear. We aim to compare rates of postoperative bleeding, stroke and major adverse events (stroke, death or MI) among patients on Aspirin alone (ASAA) versus DAPT (Clopidogrel and Aspirin).

METHODS

Patients undergoing CEA for carotid artery stenosis between 2010 and 2021 in the Vascular Quality Initiative (VQI) were included. We excluded patients undergoing concomitant or re-do operations or patients with missing antiplatelet information. Propensity score matching was performed between the 2 groups ASAA and DAPT based on age, sex, race, presenting symptoms, major comorbidities [hypertension, diabetes and coronary artery disease (CAD)], degree of ipsilateral stenosis, presence of contralateral occlusion, as well as preoperative medications. Intergroup differences between the treatment groups and differences in perioperative outcomes were tested with the McNemar's test for categorical variables and paired t-test or Wilcoxon matched-pairs signed-rank test for continuous variables where appropriate. Relative risks with 95% confidence intervals were estimated as the ratio of the probability of the outcome event in the patients treated within each treatment group.

RESULTS

A total of 125,469 patients were included [ASAA n = 82,920 (66%) and DAPT n = 42,549 (34%)]. Patients on DAPT were more likely to be symptomatic, had higher rates of CAD, prior percutaneous coronary intervention or coronary artery bypass grafting, and higher rates of diabetes. After propensity score matching, the DAPT group had an increased rate of bleeding complications (RR: 1.6: 1.4-1.8, P < 0.001) as compared with those on ASAA despite being more likely to receive both drains and protamine. In addition, patients on DAPT had a slight decrease in the risk of in-hospital stroke as compared with patients on ASAA (RR: 0.80: 0.7-0.9, P = 0.001).

CONCLUSIONS

This large multi-institutional study demonstrates a modest decrease in the risk of in-hospital stroke for patients on DAPT undergoing CEA as compared with those on ASAA. This small benefit is at the expense of a significant increase in the risk of perioperative bleeding events incurred by those on DAPT at the time of CEA. This analysis suggests avoiding DAPT when possible, during CEA.

Evaluating postoperative outcomes in patients with hostile neck anatomy undergoing transcarotid artery revascularization versus transfemoral carotid artery stenting

BACKGROUND

Carotid endarterectomy is relatively contraindicated in patients with a hostile neck anatomy who were historically revascularized with transfemoral carotid artery stenting (TFCAS). As transcarotid artery revascularization (TCAR) has progressively replaced TFCAS, evidence pertaining to hostile neck anatomy and TCAR is necessary to establish its safety and feasibility in this subgroup of patients. Therefore, we analyzed the impact of a hostile neck anatomy on outcomes in patients undergoing TCAR and further compared them with those undergoing TFCAS to establish recommendations for standard of care.

METHODS

All patients undergoing TCAR and TFCAS from November 2016 to June 2021 in the Vascular Quality Initiative database were included. Patients were characterized into two groups based on the neck anatomy. Hostile neck anatomy was defined as a history of neck radiation or prior neck surgery including prior carotid endarterectomy or radical neck dissection. Primary outcomes included technical failure, access site complications (hematoma, stenosis, infection, pseudoaneurysm and arteriovenous fistula), and stroke or death. Secondary outcomes included stroke, transient ischemic attack (TIA), myocardial infarction (MI), death, and a composite end point of stroke or TIA. Patients with nonatherosclerotic or multiple lesions were excluded from the analysis. Primary analysis was performed with all patients undergoing TCAR and outcomes between patients with hostile and nonhostile neck anatomy were compared. Further analysis included a comparison of patients with a hostile neck anatomy undergoing TCAR and TFCAS. Univariable and multivariable logistic regression was used to assess impact of hostile neck anatomy on postoperative outcomes. Results were adjusted for relevant potential confounders including age, gender, race, degree of stenosis, symptomatic status, comorbidities, preoperative medications, anesthesia type, and protamine use.

RESULTS

Among the 19,859 patients who underwent TCAR during the study period, 3636 (18.3%) had a hostile neck anatomy. On univariate analysis, both groups had comparable outcomes except for higher rates of stroke or death in patients with hostile neck anatomy. After adjusting for potential confounders, there were no differences in technical failure (adjusted odds ratio [aOR], 1.14; 95% confidence interval [CI], 0.59-2.21; P = .699), stroke (aOR, 0.86; 95% CI, 0.58-1.28; P = .464), death (aOR, 0.82; 95% CI, 0.39-1.71; P = .598), and MI (aOR, 1.18; 95% CI, 0.71-1.97; P = .518). However, patients with hostile neck were at a 30% increased risk of access site complications (aOR, 1.30; 95% CI, 1.0-1.6; P = .023). Further adjusted analysis comparing the outcomes in TFCAS and TCAR among patients with hostile neck anatomy showed an almost four-fold increase in risk of death (aOR, 3.77; 95% CI, 1.49-9.53; P = .005) and technical failure (aOR, 3.69; 95% CI, 1.82-7.47; P < .001) among patients undergoing treatment with TFCAS.

CONCLUSIONS

Patients with a hostile neck anatomy undergoing TCAR experienced an increased risk of access site complications; however, the risk for technical failure and postoperative stroke/death, stroke, TIA, MI, or death was similar among both groups. TFCAS was associated with significant increase in the risk of death and technical failure compared with TCAR in this group of patients. These results confirm that TCAR should be the preferred minimally invasive revascularization procedure for patients with hostile neck anatomy.

Perioperative and long-term outcomes after open conversion of endovascular aneurysm repair versus primary open aortic repair

BACKGROUND

The use of endovascular abdominal aortic aneurysm repair (EVAR) has superseded that of open aneurysm repair (OAR) as the procedure of choice for abdominal aortic aneurysm repair. However, significant rates of late reintervention and aneurysm rupture have been reported after EVAR, resulting in the need for conversion to OAR (C-OAR). To assess the relative effects of C-OAR on patients, we compared the outcomes of these patients to those of patients who had undergone P-OAR.

METHODS

The data from all patients who had undergone C-OAR and P-OAR in the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database from 2003 to 2018 were queried. Multivariable logistic regression and Kaplan-Meier survival and Cox proportional hazard regression analyses were used to assess the perioperative long-term outcomes.

RESULTS

A total of 4763 patients were included (91.4%, P-OAR; 8.6%, C-OAR). C-OAR was associated with a significant increase in the odds of perioperative mortality (odds ratio, 1.7; 95% confidence interval [CI], 1.1-2.7; P = .027) and renal complications (odds ratio, 1.5; 95% CI, 1.1-2; P = .004) vs P-OAR. At 5 years, conversion was associated with a higher risk of mortality (hazard ratio [HR], 1.5; 95% CI, 1.3-1.9; P < .001), aneurysmal rupture (HR, 1.9; 95% CI, 1.2-3.1; P = .007), and reintervention (HR, 1.4; 95% CI, 1.05-1.97; P = .022) compared with P-OAR. These results also persisted at 10 years, with conversion associated with a higher risk of mortality (HR, 1.5; 95% CI, 1.2-1.8; P < .001), rupture (HR, 1.8; 95% CI, 1.1-2.8; P = .018), and reintervention (HR, 1.5; 95% CI, 1.1-2.1; P = .010).

CONCLUSIONS

The results from the present study have demonstrated that C-OAR is associated with a significantly higher risk of perioperative morbidity and mortality compared with P-OAR. We found a significant increase in mortality, aneurysm rupture, and reintervention at 5 and 10 years of follow-up.

Role of Renin-Angiotensin-Aldosterone System Inhibition in Patients Undergoing Carotid Revascularization

Background

Previous data suggest that using renin‐angiotensin‐aldosterone system inhibitors (RAASIs) improves survival in patients with cardiovascular diseases. We sought to investigate the association of different patterns of use of RAASIs on perioperative and 1‐year outcomes following carotid revascularization.

Methods and Results

We investigated patients undergoing carotid revascularization, either with carotid endarterectomy or transfemoral carotid artery stenting, in the VQI (Vascular Quality Initiative) VISION (Vascular Implant Surveillance and Interventional Outcomes Network) data set between 2003 and 2018. We divided our cohort into 3 groups: (1) no history of RAASI intake, (2) preoperative intake only, and (3) continuous pre‐ and postoperative intake. The final cohort included 73 174 patients; 44.4% had no intake, 50% had continuous intake, and 5.6% had only preoperative intake. Compared with continuous intake, preoperative and no intake were associated with higher odds of postoperative stroke (odds ratio [OR], 1.7 [95% CI, 1.5–1.9]; P<0.001; OR, 1.1 [95% CI, 1.03–1.2]; P=0.010); death (OR, 4.8 [95% CI, 3.8–6.1]; P<0.001; OR, 1.9 [95% CI, 1.6–2.2]; P<0.001); and stroke/death (OR, 2.05 [95% CI, 1.8–2.3]; P<0.001; OR, 1.2 [95% CI, 1.1–1.3]; P<0.001), respectively. At 1 year, preoperative and no intake were associated with higher odds of stroke (hazard ratio [HR], 1.4 [95% CI, 1.3–1.6]; P<0.001; HR, 1.15, [95% CI, 1.08–1.2]; P<0.001); death (HR, 1.7 [95% CI, 1.5–1.9]; P<0.001; HR, 1.3 [95% CI, 1.2–1.4]; P<0.001); and stroke/death (HR, 1.5 [95% CI, 1.4–1.7]; P<0.001; HR, 1.2 [95% CI, 1.17–1.3]; P<0.001), respectively.

Conclusions

Compared with subjects discontinuing or never starting RAASIs, use of RAASIs before and after carotid revascularization was associated with a short‐term stroke and mortality benefit. Future clinical trials examining prescribing patterns of RAASIs should aim to clarify the timing and potential to maximize the protective effects of RAASIs in high‐risk vascular patients.

Long-term Outcomes Associated With Open vs Endovascular Abdominal Aortic Aneurysm Repair in a Medicare-Matched Database

IMPORTANCE

Endovascular aneurysm repair is associated with a significant reduction in perioperative mortality and morbidity compared with open aneurysm repair in the treatment of abdominal aortic aneurysm. However, this benefit decreases over time owing to increased reinterventions and late aneurysm rupture after endovascular repair.

OBJECTIVE

To compare long-term outcomes of endovascular vs open repair of abdominal aortic aneurysm.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter retrospective cohort study used deidentified data with 6-year follow-up from the Medicare-matched Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database. Patients undergoing first-time elective endovascular or open abdominal aortic aneurysm repair from 2003 to 2018 were propensity score matched. Patients with ruptured abdominal aortic aneurysm, concomitant procedures, or prior history of abdominal aortic aneurysm repair, were excluded. Data were analyzed from January 1, 2003, to December 31, 2018.

EXPOSURES

First-time elective endovascular or open repair for abdominal aortic aneurysm.

MAIN OUTCOMES AND MEASURES

The primary long-term outcome of interest was 6-year all-cause mortality, rupture, and reintervention. Secondary outcomes included 30-day mortality and perioperative complications.

RESULTS

Among a total of 32 760 patients (median [IQR] age, 75 [70-80] years; 25 706 [78.5%] men) who underwent surgical abdominal aortic aneurysm repair, 28 281 patients underwent endovascular repair and 4479 patients underwent open repair. After propensity score matching, there were 2852 patients in each group. Open repair was associated with significantly lower 6-year mortality compared with endovascular repair (548 deaths [35.6%] vs 608 deaths [41.2%]; hazard ratio [HR], 0.83; 95% CI, 0.74-0.94; P = .002), with increases in mortality starting from 1 to 2 years (84 deaths [4.3%] vs 126 deaths [6.7%]; HR, 0.63; 95% CI, 0.48-0.83; P = .001) and 2 to 6 years (211 deaths [25.8%] vs 241 deaths [30.6%]; HR, 0.73; 95% CI, 0.61-0.88; P = .001). Open repair, compared with endovascular repair, also was associated with significantly lower rates of 6-year rupture (117 participants [5.8%] vs 149 participants [8.3%]; HR, 0.76; 95% CI, 0.60-0.97; P < .001) and reintervention (190 participants [11.6%] vs 267 participants [16.0%]; HR, 0.67; 95% CI, 0.55-0.80; P < .001). Open repair was associated with significantly higher odds of 30-day mortality (OR, 3.56; 95% CI, 2.41-5.26; P < .001) and complications.

CONCLUSIONS AND RELEVANCE

These findings suggest that overall mortality after elective abdominal aortic aneurysm repair was higher with endovascular repair than open repair despite reduced 30-day mortality and perioperative morbidity after endovascular repair. Endovascular repair additionally was associated with significantly higher rates of long-term rupture and reintervention. These findings emphasize the importance of careful patient selection and long-term follow-up surveillance for patients who undergo endovascular repair.

Impact of Frailty on Postoperative Outcomes in Patients undergoing TransCarotid Artery Revascularization (TCAR)

BACKGROUND

Frailty is a clinical syndrome characterized by reduction in metabolic reserves leading to increased susceptibility to adverse outcomes following invasive surgical interventions. The 5-item modified frailty index (mFI-5) validated in prior studies has shown high predictive accuracy for all surgical specialties including vascular procedures. In this study we aim to utilize the mFI-5 to predict outcomes in Transcarotid Revascularization (TCAR).

METHODS

All patient who underwent TCAR from November 2016 to April 2021 in the Vascular Quality Initiative (VQI) Database were included. The mFI-5 was calculated as a cumulative score divided by 5 with 1 point each for poor functional status, presence of diabetes, chronic obstructive pulmonary disease (COPD), congestive heart failure (CHF), and hypertension. Patients were stratified into two groups based on prior studies: low mFI-5 (0.6) and high (≥0.6). Primary outcomes included in-hospital death, extended length of postoperative stay (> 1 day), and non-home discharge. Secondary outcomes included in-hospital stroke, transient ischemic attack (TIA), myocardial infarction (MI), and composite endpoint of stroke/death, stroke/TIA and stroke/death/MI. Univariate and multivariable logistic regression were used to assess the association between mFI-5 and postoperative outcomes. Secondary analysis stratified by symptomatic status was performed.

RESULTS

Out of the 17,983 patients who underwent TCAR, 4526(25.2%) had mFI-5 score of ≥0.6 and considered clinically frail. Compared to the non-frail group, frail patients were more likely to be female (38.7% vs 35.6%, p<0.001), have poor functional status (43.6 vs 8.3%, p<0.001), and present with significant comorbidities including diabetes (75.3% vs 26.1%, p<0.001), hypertension (98.9% vs 88.5%, p<0.001), CHF (52.2% vs 5.6, p<0.001), and COPD (60.3% vs 14.2%, p<0.001). They were also more likely to be active smokers (25.4% vs 20.4%, p<0.001) and symptomatic prior to intervention (28.7% vs 25.3%, p<0.001). On univariate analysis, frail patients were at significantly higher risk to experience adverse outcomes including in-hospital mortality, TIA, MI, stroke/death, stroke/TIA, stroke/death/MI, discharge to non-home facility, and extended LOS. After adjusting for potential confounders, frail patients remained at significantly higher risk of in-hospital mortality [aOR 2.26(1.41,3.61), p=0.001], TIA [aOR 1.65(1.08, 2.54), p=0.040], non-home discharge [aOR 1.99(1.71,2.32) p<0.001], and extended LOS [aOR 1.41(1.27, 1.55) p<0.001]. On further stratified analysis based on symptomatic status, the increased risk of stroke/death, TIA, and death was observed only in symptomatic patients.

CONCLUSION

Modified Frailty Index is a reliable tool that can be used to identify high risk patients for TCAR prior to intervention. This could help vascular surgeons, patients, and families in informed decision making to further optimize perioperative care and medical management in frail patients.

Impact of Routine Intracerebral Completion Angiography on Outcomes After TransCarotid Artery Revascularization

OBJECTIVES

Completion intracerebral angiography (CIA) following transcarotid artery revascularization (TCAR) aims to identify distal embolization after stenting and serve as a measure of intraoperative quality control. Nevertheless, there is no general evidence regarding the benefit of performing routine CIA. The aim of this study was to evaluate the potential risk and benefit of routine CIA.

METHODS

We retrospectively reviewed the Vascular Quality Initiative (VQI) database for transcarotid artery revascularization between 2016-2021. Patients were divided into two groups: patients with no CIA performed and those with completion angiography performed. The primary outcome was in-hospital stroke or death. Secondary outcomes included stroke, death, myocardial infarction (MI) and return to the operating room (RTOR). Clinically relevant and statistically significantly variables on univariable analysis were added to a logistic regression model clustered by center identifier.

RESULTS

A total of 18,155 patients who underwent TCAR were identified, 63.7% of them had routine CIA performed. Patients who had routine CIA were more likely to have contralateral carotid occlusion and general anesthesia. After adjusting for potential confounders, we found no difference in the risk of stroke or death (aOR): 1.03, 95%CI (0.8-1.3), P=.820), stroke/TIA (aOR, 1, 95%CI (0.8-1.3), P=.998), stroke (aOR: 1.1, 95%CI (0.8-1.4), P=.452), death (aOR: 0.98, 95%CI (0.6-1.6), P=.953), MI (aOR: 0.78, 95%CI (0.5-1.2), P=.240), or RTOR (aOR: 1.5, 95%CI (0.6-3.8), P=.412) between patients who had CIA compared to those who did not. A sub-analysis of patients who had new occlusion detected on CIA (69 patients, 0.6%; 19 not treated and 50 treated) indicated higher risk of stroke or death in patients with treated new occlusions (OR: 7.1, 95%CI (2.9-17.3), P<.001) and stroke/TIA (aOR, 5.8, 95%CI (2.3-14.7), P<.001) compared to patients who had no CIA. However, no difference in stroke/death (OR: 3.3, 95%CI (0.37-29.5), P=.283) or stroke/TIA (aOR, 3.1, 95%CI (0.3-29.4), P=.327) was found in patients with non-treated new occlusions compared to patients who had no CIA.

CONCLUSIONS

In this retrospective study, routine performance of completion cerebral angiography was not beneficial with no significant differences in in-hospital stroke or death detected. Detection of new lesions on completion cerebral angiography was rare. Moreover, identifying new occlusions following intracranial angiography was associated with higher odds of stroke or death when these new lesions are treated. Further studies are needed to define the etiology of worse outcomes in patients undergoing intervention for lesions discovered on completion cerebral angiogram and delineate optimal timing for further imaging and intervention.

The impact of carotid lesion calcification on outcomes of carotid artery stenting

OBJECTIVE

The impact of carotid artery lesion calcification on adverse events following carotid artery stenting is not well-studied. Few reports associated heavily calcified lesions with high risk of perioperative stroke following transfemoral carotid artery stenting (TFCAS). With the advent of transcarotid artery revascularization (TCAR), we aimed to compare the outcomes of these two procedures stratified by the degree of lesion calcification.

METHODS

Our cohort was derived from the Vascular Quality Initiative database for carotid artery stenting. Patients with missing information on the degree of carotid artery calcification were excluded. Patients were stratified into two groups: >50% (heavy) calcification and ≤50% (no/mild) calcification. The Student t test and the χ² test were used to compare patients' baseline characteristics and crude outcomes, as appropriate. Clinically relevant and statistically significantly variables on univariable analysis were added to a logistic regression model clustered by center identifier.

RESULTS

A total of 11,342 patients were included. Patients with >50% calcification were older, had more comorbidities, and more contralateral occlusion. There were more patients with prior ipsilateral carotid endarterectomy in the ≤50% calcification group. In patients who underwent TCAR, there were no significant differences between those who had >50% vs ≤50% carotid calcification in the odds of in-hospital adverse outcomes. However, in patients with heavy calcification who underwent TFCAS, there was a 50% to 60% increase in the odds of stroke (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.04-2.5; P = .03), stroke/transient ischemic attack (TIA) (OR, 1.6; 95% CI, 1.1-2.3; P = .013), and stroke/death (OR, 1.5; 95% CI, 1.02-2.08; P = .039). Compared with TFCAS in patients with heavy calcification, TCAR was associated with a 40% to 90% reduction in the odds of contralateral stroke (OR, 0.13; 95% CI, 0.04-0.4; P = .001), contralateral stroke/TIA (OR, 0.3; 95% CI, 0.1-0.87; P = .024), any stroke/TIA (OR, 0.6; 95% CI, 0.38-0.91; P = .02), death (OR, 0.3; 95% CI, 0.13-0.72; P = .006), stroke/death (OR, 0.5; 95% CI, 0.32-0.8; P = .004), and stroke/death/myocardial infarction (OR, 0.58; 95% CI, 0.39-0.87; P = .008). There were no significant differences in the odds of stroke and myocardial infarction.

CONCLUSIONS

In this retrospective analysis of patients undergoing TFCAS vs TCAR in the Vascular Quality Initiative database, TCAR demonstrated favorable outcomes compared with TFCAS among patients with calcification greater than 50% of the carotid circumference. Advance burden of carotid artery calcification was associated with worse outcomes in patients undergoing TFCAS but not TCAR. These results are consistent with previously demonstrated superiority of flow reversal compared with distal embolic protection devices. Further research is needed to assess long-term outcomes and confirm the durability of TCAR in heavily calcified lesions.

Propensity score-matched analysis of 1-year outcomes of transcarotid revascularization with dynamic flow reversal, carotid endarterectomy, and transfemoral carotid artery stenting

OBJECTIVE

Initial studies showed no significant differences in perioperative stroke or death between transcarotid artery revascularization (TCAR) and carotid endarterectomy (CEA) and lower stroke/death rates after TCAR compared with transfemoral carotid artery stenting (TFCAS). This study focuses on the 1-year outcomes of ipsilateral stroke or death after TCAR, CEA, and TFCAS.

METHODS

All patients undergoing TCAR, TFCAS, and CEA between September 2016 and December 2019 were identified in the Vascular Quality Initiative (VQI) database. The latest follow-up was September 3, 2020. One-to-one propensity score-matched analysis was performed for patients with available 1-year follow-up data for TCAR vs CEA and for TCAR vs TFCAS. Kaplan-Meier survival and Cox proportional hazard regression analyses were used to evaluate 1-year ipsilateral stroke or death after the three procedures.

RESULTS

A total of 41,548 patients underwent CEA, 5725 patients underwent TCAR, and 6064 patients underwent TFCAS during the study period and had recorded 1-year outcomes. The cohorts were well-matched in terms of baseline demographics and comorbidities. Among 4180 TCAR vs CEA matched pairs of patients, there were no significant differences in 30-day stroke, death, and stroke/death. However, TCAR was associated with a lower risk of 30-day stroke/death/myocardial infarction (2.30% vs 3.25%; relative risk, 0.71; 95% confidence interval [CI], 0.55-0.91; P = .008), driven by a lower risk of myocardial infarction (0.55% vs 1.12%; hazard ratio [HR], 0.49; 95% CI, 0.30-0.81; P = .004). At 1 year, no significant difference was observed in the risk of ipsilateral stroke or death (6.49% vs 5.68%; HR, 1.14; 95% CI, 0.95-1.37; P = .157). Among 4036 matched pairs in the TCAR vs TFCAS group, TCAR was also associated with lower risk of perioperative stroke or death compared with TFCAS (1.83% vs 2.55%; HR, 0.72; 95% CI, 0.54-0.96; P = .027). At 1 year, the risks of ipsilateral stroke or death of TCAR and TFCAS were comparable (6.07% vs 7.07%; HR, 0.85; 95% CI, 0.71-1.01; P = .07). Symptomatic status did not modify the association in TCAR vs CEA. However, asymptomatic patients had favorable outcomes with TCAR vs TFCAS at 1 year (HR, 0.78; 95% CI, 0.62-0.98; P = .033).

CONCLUSIONS

In this propensity score-matched analysis, no significant differences in ipsilateral stroke/death-free survival were observed between TCAR and CEA or between TCAR and TFCAS. The advantages of TCAR compared with TFCAS seem to be mainly in the perioperative period, which makes it a suitable minimally invasive option for surgically high-risk patients with carotid artery stenosis. Larger studies, with longer follow-up and data on restenosis, are warranted to confirm the mid- and long-term benefits and durability of TCAR.

Outcomes of Carotid Revascularization in the Treatment of Restenosis After Prior Carotid Endarterectomy

BACKGROUND AND PURPOSE

Restenosis after carotid endarterectomy (CEA) is associated with an increased risk of ipsilateral stroke. The optimal procedural modality for this indication has yet to be determined. Here, we evaluate the in-hospital outcomes of transcarotid artery revascularization (TCAR), redo-CEA, and transfemoral carotid artery stenting (TFCAS) in a large contemporary cohort of patients who underwent treatment for restenosis after CEA.

METHODS

We performed a retrospective analysis of all patients in the vascular quality initiative database who underwent TCAR, redo-CEA, or TFCAS after ipsilateral CEA between September 2016 and April 2020. Patients with prior ipsilateral CAS were excluded from this analysis. In-hospital outcomes following TCAR versus CEA and TCAR versus TFCAS were evaluated using multivariate logistic regression analysis.

RESULTS

A total of 4425 patients were available for this analysis. There were 963 (21.8%) redo-CEA, 1786 (40.4%) TFCAS, and 1676 (37.9%) TCAR. TCAR was associated with lower odds of in-hospital stroke/death (odds ratio [OR], 0.41 [95% CI, 0.24-0.70], P=0.021), stroke (OR, 0.46 [95% CI, 0.23-0.93], P=0.03), myocardial infarction (MI; OR, 0.32 [95% CI, 0.14-0.73], P=0.007), stroke/transient ischemic attack (OR, 0.42 [95% CI, 0.24-0.74], P=0.002), and stroke/death/MI (OR, 0.41 [95% CI, 0.24-0.70], P=0.001) when compared with redo-CEA. There was no significant difference in the odds of death between the 2 groups (OR, 0.99 [95% CI, 0.28-3.5], P=0.995). TCAR was also associated with lower odds of stroke/transient ischemic attack (OR, 0.37 [95% CI, 0.18-0.74], P=0.005) when compared with TFCAS. There was no significant difference in the odds of stroke, death, MI, stroke/death, or stroke/death/MI between TCAR and TFCAS.

CONCLUSIONS

TCAR was associated with significantly lower odds of in-hospital stroke, MI, stroke/transient ischemic attack, stroke/death, and stroke/death/MI when compared with redo-CEA and lower odds of in-hospital stroke/transient ischemic attack when compared with TFCAS. Additional long-term studies are warranted to establish the role of TCAR for the treatment of restenosis after CEA.

Outcomes of Carotid Revascularization in Patients with Contralateral Carotid Artery Occlusion

BACKGROUND

Little is known about the best revascularization procedure for patients with contralateral carotid artery occlusion (CCO). We aim to compare the outcomes of transcarotid artery revascularization (TCAR), carotid endarterectomy (CEA), and transfemoral carotid artery stenting (TFCAS) in patients with CCO.

STUDY DESIGN

Patients in the Vascular Quality Initiative dataset who underwent CEA, TFCAS, or TCAR, and had CCO between September 2016 and April 2020, were included. Multivariable logistic analysis was used to evaluate in-hospital outcomes.

RESULTS

The final cohort included 1,144 TCARs, 1,182 TFCAS, and 2,527 CEA procedures performed in patients with CCO. Compared with TFCAS, TCAR was associated with a significant reduction in the odds of in-hospital stroke or death (odds ratio [OR] 0.26; 95% CI: 0.12-0.59; p < 0.01). However, no significant difference in stroke was noted (OR 0.71; 95% CI 0.34-1.51; p = 0.38). These results persisted after stratifying with respect to symptomatic status (p values of interaction = 0.92 and 0.74, respectively). There was no significant difference between TCAR and CEA in odds of in-hospital stroke or death on multivariable adjustment (OR 0.57; 95% CI: 0.29-1.10, p = 0.10). The interaction between procedure type and symptomatic status in predicting in-hospital stroke was statistically significant (p = 0.04). In asymptomatic patients, TCAR was associated with a 50% to 60% reduction in the odds of stroke (p = 0.04). Yet, no significant differences were observed in symptomatic patients.

CONCLUSIONS

TCAR has lower odds of in-hospital stroke or death compared to TFCAS, independent of symptomatic status. Compared to CEA, TCAR seems to be a better option in asymptomatic patients, with lower odds of in-hospital stroke. Yet, no significant difference is observed in symptomatic patients.

Thromboembolism risk of COVID-19 is high and associated with a higher risk of mortality: A systematic review and meta-analysis

BACKGROUND

Studies have suggested that there is increased risk of thromboembolism (TE) associated with coronavirus disease 2019 (COVID-19). However, overall arterial and venous TE rates of COVID-19 and effect of TE on COVID-19 mortality is unknown.

METHODS

We did a systematic review and meta-analysis of studies evaluating TE in COVID-19. We searched PubMed, Cochrane, and Embase for studies published up to June 12, 2020. Random effects models were used to produce summary TE rates and odds ratios (OR) of mortality in COVID-19 patients with TE compared to those without TE. Heterogeneity was quantified with I 2 .

FINDINGS

Of 425 studies identified, 42 studies enrolling 8271 patients were included in the meta-analysis. Overall venous TE rate was 21% (95% CI:17-26%): ICU, 31% (95% CI: 23-39%). Overall deep vein thrombosis rate was 20% (95% CI: 13-28%): ICU, 28% (95% CI: 16-41%); postmortem, 35% (95% CI:15-57%). Overall pulmonary embolism rate was 13% (95% CI: 11-16%): ICU, 19% (95% CI:14-25%); postmortem, 22% (95% CI:16-28%). Overall arterial TE rate was 2% (95% CI: 1-4%): ICU, 5% (95%CI: 3-7%). Pooled mortality rate among patients with TE was 23% (95%CI:14-32%) and 13% (95% CI:6-22%) among patients without TE. The pooled odds of mortality were 74% higher among patients who developed TE compared to those who did not (OR, 1.74; 95%CI, 1.01-2.98; P = 0.04).

INTERPRETATION

TE rates of COVID-19 are high and associated with higher risk of death. Robust evidence from ongoing clinical trials is needed to determine the impact of thromboprophylaxis on TE and mortality risk of COVID-19.

FUNDING

None.

Laboratory-based surveillance of patients with bacterial meningitis in Egypt (1998–2004)

Laboratory-based surveillance for bacterial meningitis was conducted in a network of infectious disease hospitals in Egypt to better understand the epidemiology of this infection. Healthcare and laboratory personnel were trained in basic surveillance and microbiologic processing of cerebrospinal fluid (CSF) specimens. All bacterial isolates from CSF were confirmed and tested for antimicrobial susceptibility. PCR testing was performed on a random subset of purulent, culture-negative CSF specimens. Of 11,070 patients who met criteria for the case definition, 843 (8%) were culture positive (42% positive for Streptococcus pneumoniae, 20% for Haemophilus influenzae serotype b, 17% for each of Neisseria meningitidis and Mycobacterium tuberculosis, and 6% for other bacteria). Of 1,784 (46%) CSF specimens tested by PCR, 232 (13%) were positive for the first three major pathogens. Of N. meningitidis isolates, 52% belonged to serogroup A, 35% to serogroup B, and 4% to serogroup W135. S. pneumoniae isolates comprised 46 different serotypes, of which 6B, 1, 19A, 23F, and 6A were the most predominant. The overall case-fatality rate for culture-positive cases was 26% and was highest among patients with M. tuberculosis (47%). Factors significantly associated with death (p < 0.05) included admission to rural hospitals, long prodromal period, referral from other hospitals, antibiotic treatment prior to admission, and clear CSF (<100 cells/mm3). Susceptibility to ampicillin and ceftriaxone was observed in 44 and 100% of H. influenzae serotype b isolates and in 52 and 94% of S. pneumoniae isolates, respectively. This surveillance highlights the significant mortality and morbidity associated with bacterial meningitis in Egypt. Decision makers need to review current treatment guidelines and introduce appropriate vaccines for prevention and control of the disease.

Exposure to sublethal blast overpressure reduces the food intake and exercise performance of rats

Exposure to blast overpressure can typically inflict generalized damage on major organ systems, especially gas-containing organs such as the lungs and the gastrointestinal tract. The purpose of the present study was to use rat's food intake and exercise wheel running as behavioral correlates of the perhaps more subtle damage to these organ systems induced by sublethal blast overpressure. Toward this end, all rats were exposed to a 12-h light/dark cycle and food was available only in the dark period. Prior to exposure, rats in the (E)xercise group were required to execute five rotations of an activity wheel for a food pellet; wheel turns that occurred at times other than when a rat was feeding were recorded separately and labeled exercise running. In the (S)edentary and (A)nesthesia groups, wheel running was not possible and rats were required to execute five leverpresses for a single pellet. A compressed air-driven shock tube was used to expose rats to a supra-atmospheric wave of air pressure. The tube was separated into two sections by a polyester membrane, the thickness of which determined peak and duration of overpressure. All rats were anesthetized with 50 mg/kg of phenobarbital. After reaching a deep plane of anesthesia, they were individually tied in a stockinet across one end of the shock tube. In preliminary tests, the membrane thickness was 1000 (A)ngstroms and rats in Group L(ethality) were exposed to a 129 kPa (peak amplitude) wave of overpressure. Three of six rats survived exposure to this peak pressure; pathology was evident in the lungs and gastrointestinal tract of all non-survivors. Rats in Groups E and S were tested with a 500 A membrane, which resulted in an 83 kPa peak amplitude. All rats survived exposure to this lower peak pressure. On the day of exposure to blast, the relative reduction of intake during the first 3 h of the dark period was significantly greater for Group E than for Groups S and A; the intake of Groups E and S remained reduced for four additional recovery days. Bodyweight was not significantly affected. Exercise wheel running also was reduced significantly on the day of exposure and during subsequent recovery days. These preliminary findings suggest that exposure to sublethal blast overpressure can reduce food consumption and exercise performance, perhaps as a consequence of damage to the gastrointestinal tract and lungs.

Pulmonary microsomes contain a Ca(2+)-transport system sensitive to oxidative stress

A variety of events, including inhalation of atmospheric chemicals, trauma, and ischemia-reperfusion, may cause generation of reactive oxygen species in the lung and result in airways constriction. The specific metabolic mechanisms that translate oxygen radical production into airways constriction are yet to be identified. In the lung, calcium homeostasis is central to release of bronchoactive and vasoactive chemical mediators and to regulation of smooth muscle cell contractility, i.e., airway constriction. In the present work, we characterized Ca(2+)-transport in the microsomal fraction of mouse lungs, and determined how reactive oxygen species, generated by Fe2+/ascorbate and H2O2/hemoglobin, affected Ca2+ transport. The microsomal fraction of pulmonary tissue accumulated 90 +/- 5 nmol Ca2+/mg protein by an ATP-dependent process in the presence of 15 mM oxalate, and 16 +/- 2 nmol Ca2+ in its absence. In the presence of oxalate, the rate of Ca2+ uptake was 50 +/- 5 nmol Ca2+/min per mg protein at pCa 5.9 (37 degrees C). The Ca(2+)-ATPase activity was 50-60 nmol Pi/min per mg protein (pCa 5.9, 37 degrees C) in the presence of alamethicin. Inhibitors of mitochondrial H(+)-ATPase had no effect on the Ca2+ transport. Half-maximal activation of Ca2+ transport was produced by 0.4-0.5 microM Ca2+. Endoplasmic reticulum Ca(2+)-pump (SERC-ATPase) was found to be predominantly responsible for the Ca(2+)-accumulating capacity of the pulmonary microsomes. Incubation of the microsomes in the presence of either Fe2+/ascorbate or H2O2/hemoglobin resulted in a time-dependent accumulation of peroxidation products (TBARS) and in inhibition of the Ca2+ transport. The inhibitory effect of Fe2+/ascorbate on Ca2+ transport strictly correlated with the inhibition of the Ca(2+)-ATPase activity. These results are the first to indicate a highly active microsomal Ca2+ transport system in murine lungs which is sensitive to endogenous oxidation products. The importance of this system to pulmonary disorders exacerbated by oxidative chemicals remains to be studied.

Effects of vitamin E deficiency and nitrogen dioxide exposure on lung lipid peroxidation: use of lipid epoxides and malonaldehyde as measures of peroxidation

The effect of vitamin E deficiency in male Sprague-Dawley rats upon lipid peroxidation in lung tissue was examined by measuring malonaldehyde and lipid epoxide production. In addition to controls, some animals were also exposed to 3 +/- 0.1 ppm NO2 continuously for 7 d in order to study the effects of oxidant stress on lung lipid peroxidation and vitamin E content. The observed changes in malonaldehyde and epoxide content could serve as good indices of lipid peroxidation, particularly under conditions of vitamin E deprivation. The responses measured indicated an inverse relation in the lung between tissue vitamin E content and quantity of lipid peroxidation products. Measurement of lipid epoxides served as a reliable indicator of lung tissue lipid peroxidation. Finally, NO2 inhalation appeared to elicit a response characterized by increased assimilation of vitamin E into lung tissue.

Influence of vitamin E and nitrogen dioxide on lipid peroxidation in rat lung and liver microsomes

Rat lung and liver microsomes were used to examine the effects of dietary vitamin E deficiency on membrane lipid peroxidation. Microsomes from vitamin-E-deficient rats displayed increased lipid peroxidation in comparison to microsomes from vitamin-E-supplemented controls. The extent of lipid peroxidation, as determined by measurement of thiobarbituric acid reacting materials, was enhanced by addition of reduced iron and ascorbate (or NADPH). Rats fed a vitamin-E-supplemented diet and exposed to 3 ppm NO2 for 7 days did not exhibit increases in microsomal lipid peroxidation compared to air-breathing controls. However, increase were found in microsomes prepared from rats fed a vitamin-E-deficient diet and exposed to NO2. Lung microsomes from vitamin-E-fed rats contained almost 10 times as much vitamin E as liver microsomes when expressed in terms of polyunsaturated fatty acid content. The extent of lipid peroxidation was, in turn, considerably less in lung than in liver microsomes. Lipid peroxidation in lung microsomes from vitamin-E-deficient rats comparable to liver microsomes from vitamin-E-supplemented rats as was the content of vitamin E in these respective microsomal samples. A combination of vitamin E deficiency and NO2 exposure resulted in the greatest increases in lung and liver microsomal lipid peroxidation with the largest relative increases occurring in lung microsomes. An inverse relationship was found between the extent of lipid peroxidation and vitamin E content. Most of the peroxidation in lung microsomes appeared to proceed nonenzymatically whereas peroxidation in liver was largely enzymatic. Vitamin E appears to be assimilated by the lung during oxidant inhalation, but with dietary vitamin E deprivation, the margin for protection in lung may be less than in liver.