The effect of the collateral cerebrovascular circulation on tolerance to carotid artery cross-clamping and on early outcome after carotid endarterectomy.

OBJECTIVE: The Circle of Willis (CoW) serves as the primary source of contralateral blood supply in patients who undergo carotid artery cross-clamping (CC) for carotid endarterectomy (CEA). It has been suggested that the CoW's anatomy influences CEA outcomes. The aim of this study was to evaluate associations between the cerebral collateral circulation, a positive awake test for intraoperative neurologic deficit after carotid CC, and postoperative adverse neurologic events. METHODS: A systematic review was conducted searching MEDLINE, Cochrane, and Web of Science databases for studies that assessed the cerebral circulation, including CoW variations, using neuroimaging techniques in patients who underwent carotid CC. For the metanalytical incidence, the statistical technique used was weight averaging. Otherwise, descriptive analysis was used due to the excessive heterogeneity of the studies. RESULTS: Eight publications, seven cohort and one case-controlled study, involving 1313 patients who underwent carotid artery CC under loco-regional anesthesia, were included in the systematic review. The incidence of positive awake test in the cohort studies ranged from 4.4% to 19.7%. Carotid artery CC resulted in positive awake test in 5% to 91% of patients with alterations in the anterior portion and in 27% to 74% with alterations in the posterior portion of the CoW. A positive awake test in patients with contralateral carotid stenosis or occlusion ranged from 5.8% to 45.7%. Contralateral carotid stenosis >70% or occlusion were associated with a positive awake test (P < .001). Patients with incomplete CoW did not have statistically significant correlation with intraoperative neurological deficits after CC. Data were insufficient to evaluate the effect of the collateral circulation on early outcome after CEA. CONCLUSIONS: In this systematic review, contralateral carotid artery stenosis or occlusion, but not CoW abnormalities, were associated with a positive awake test after carotid artery CC. Further research is needed to evaluate which specific CoW anomaly predicts neurologic deficit after CC and to confirm association between a positive awake test and clinical outcome after CEA.

Polyvascular Disease Influences Long-Term Cardiovascular Morbidity in Carotid Endarterectomy.

INTRODUCTION/OBJECTIVE: Carotid stenosis (CS) is an important cause of ischemic stroke. Secondary prevention lies in performing a carotid endarterectomy (CEA) procedure, the recommended treatment in most cases. When 2 or more vascular regions are simultaneously affected by atherosclerosis, mainly the carotid arteries, coronary arteries, or limb arteries, a multivessel disease polyvascular disease (PVD) is present. This study aims to assess the potential role of PVD as a long-term predictor of major adverse cardiovascular events (MACE) and all-cause mortality in patients submitted to CEA. METHODS: From January 2012 to December 2021, patients submitted to CEA for carotid stenosis in a tertiary care and referral center were eligible from a prospective database. A posthoc survival analysis was performed using the Kaplan-Meier survival curve method. The primary outcome was the incidence of long-term MACE and all-cause mortality. Secondary outcomes included acute myocardial infarction (AMI), major adverse limb events (MALE), stroke, and acute heart failure (AHF). RESULTS: A total of 207 patients were enrolled, with a median follow-up of 63 months. The mean age was 70.4 ± 8.9, and 163 (78.7%) were male. There were 65 (31.4%) patients that had 2 arterial vascular territories affected, and 29 (14.0%) patients had PVD in 3 arterial beds. On multivariable analysis, both MACE and all-cause mortality had as independent risk factors age (aHR 1.039, P = 0.003; aHR 1.041, P = 0.019), chronic kidney disease (aHR 2.524, P = 0.003; aHR 3.377, P < 0.001) and PVD2 (aHR 3.381, P < 0.001; aHR 2.665, P = 0.013). PVD1 was only associated with MACE as a statistically significant risk factor (aHR 2.531, 1.439-4.450, P < 0.001). CONCLUSIONS: PVD in patients with cerebrovascular disease (CVD) was revealed to carry a 2-fold increased risk for all-cause mortality and MACE during long-term follow-up. PVD may be a simple yet valuable tool in predicting all-cause mortality, MACE, AMI, and MALE after CEA.

Gupta Perioperative Risk for Myocardial Infarction or Cardiac Arrest score is a long-term cardiovascular risk predictor after aortoiliac revascularization.

INTRODUCTION: Gupta Perioperative Risk for Myocardial Infarction or Cardiac Arrest (MICA) is a validated self-explanatory score applied in cardiac or non-cardiac surgeries. This study aims to assess the predictive value of the MICA score for cardiovascular events after aortoiliac revascularization. METHODS: This prospective cohort underwent elective aortoiliac revascularization between 2013 and 2021. Patients' demographic, clinical characteristics and outcomes were registered. The patients were divided into two groups according to the MICA score using optimal binning. Survival analysis to test for time-dependent variables and multivariate Cox regression analysis for independent predictors were performed. RESULTS: This study included 130 patients with a median follow-up of 55 months. Preoperative MICA score was ≥ 6.5 in 41 patients. MICA ≥ 6.5 presented a statistically significant association with long-term occurrence of acute heart failure (HR=1.695, 95% CI 1.208-2.379, p=0.002), major adverse cardiovascular events (HR=1.222, 95% CI 1.086-1.376, p<0.001) and all-cause mortality (HR=1.256, 95% CI 1.107-1.425, p<0.001). Multivariable Cox regression confirmed MICA as a significant independent predictor of long-term major adverse cardiovascular events (aHR=1.145 95%CI 1.010-1.298, p=0.034) and all-cause mortality (aHR=1.172 95%CI 1.026-1.339, p=0.020). CONCLUSION: The MICA score is a quick, easy-to-obtain, predictive tool in identifying patients with a higher risk of post-aortoiliac revascularization cardiovascular events, such as acute heart failure, major adverse cardiovascular events and all-cause mortality. Additional research for validation of the MICA score in the context of aortoiliac revascularization and specific interventions are necessary.

Incidence of myocardial injury in patients submitted to carotid endarterectomy.

Myocardial injury following noncardiac surgery (MINS) is associated with higher mortality and major adverse cardiovascular event rates in the short- and long-term in patients undergoing carotid endarterectomy (CEA). However, its incidence is still unclear in this subset of patients. Therefore, this systematic review with meta-analysis aims to determine the incidence of MINS in patients undergoing CEA. Three electronic databases MEDLINE, Scopus, and Web of Science were used to search for studies assessing the occurrence of MINS in the postoperative setting of patients undergoing CEA. The incidence of MINS was pooled by random-effects meta-analysis, with sources of heterogeneity being explored by meta-regression and subgroup analysis (general anesthesia vs. regional anesthesia). Assessment of studies' quality was performed using National Heart, Lung, and Blood Institute Study Quality Assessment Tool, and Risk of Bias 2 tools. Twenty studies were included, with a total of 117,933 participants. Four of them were RCTs, while the remaining were cohort studies. All observational cohorts had an overall high risk of bias, except for Pereira Macedo et al. Three of them had repeated population, thus only data from the most recent one was considered. On the other hand, all RCT had an overall low risk of bias. In patients under regional anesthesia, the incidence of MINS in primary studies ranged between 2% and 15.3%, compared to 0-42.5% for general anesthesia. The meta-analytical incidence of MINS after CEA was of 6.3% [95% CI 2.0-10.6%], but severe heterogeneity was observed (I2=99.1%). MINS appears to be relatively common among patients undergoing CEA. The observed severe heterogeneity points to the need for further larger studies adopting consistent definitions of MINS and equivalent cut-off values.

Hyperfunctioning papillary thyroid carcinoma - a case report and literature review.

BACKGROUND: Malignant hyperfunctioning thyroid nodules are rare and more likely to occur in follicular cancer types rather than papillary variants. The authors present a case of a papillary thyroid carcinoma associated with a hyperfunctioning nodule. METHODS: A single adult patient submitted to total thyroidectomy with the presence of thyroid carcinoma within hyperfunctioning nodules was selected. Additionally, brief literature was conducted. RESULTS: An asymptomatic 58-year-old male was subjected to routine blood analysis and a TSH level of <0.003 mIU/L was found. Ultrasonography revealed a 21 mm solid, hypoechoic, and heterogenous nodule with microcalcifications in the right lobe. A fine needle aspiration guided by ultrasound resulted in a follicular lesion of undetermined significance. A 99mTc thyroid scintigram was followed and identified a right-sided hyperfunctioning nodule. Another cytology was performed and a papillary thyroid carcinoma was derived as a result. The patient underwent a total thyroidectomy. Postoperative histology confirmed the diagnosis and a tumor-free margin with no vascular or capsular invasions. CONCLUSION: Hyperfunctioning malignant nodules are a rare association, although a careful approach should be led since major clinical implications arise. Selective fine needle aspiration in all suspicious ≥1 cm nodules should be considered.

Blood group is a long-term cardiovascular risk factor after carotid endarterectomy.

BACKGROUND: ABO blood group system has been clinically related to an increased incidence of cardiovascular diseases. Preliminary data relating Rhesus (Rh) factor and these outcomes also have been published. Our aim was to analyse the impact of blood group on the short and long-term outcomes after carotid endarterectomy (CEA). MATERIALS AND METHODS: From 2012 to 2019, patients from a referral centre who underwent CEA for atherosclerotic carotid stenosis were prospectively followed. Our primary outcomes were long-term major adverse cardiovascular events (MACEs) and all-cause mortality. Secondary outcomes were perioperative complications and myocardial injury after non-cardiac surgery (MINS). Median follow-up was 50 months (interquartile range 21-69). Time-to-event analysis was used to determine the effect of ABO and Rh groups in long-term outcomes. RESULTS: One hundred and eighty-four patients were included, with a mean age of 70.1 ± 9.1 years. Eighteen (25.7%) patients with O type and 48 (42.1%) patients with non-O type presented coronary artery disease (odds ratio [OR]: 2.313, 5-95% confidence interval (CI) 1.245-4.297, p = .008). Patients Rh+ presented significantly more congestive heart failure, 23 (14.7%), p = .03. The incidence of MACE in the long-term was higher in non-O patients (adjusted hazard ratio: 2.034; CI: 1.032-4.010, p = .040). Rh- patients, presented a higher incidence of perioperative MINS. However, there was no statistically significant association with long-term risk of MACE. CONCLUSION: The incidence of MACE in long-term analysis was higher in non-O blood type and 30-day MINS was significantly more common amongst Rh- patients. The benefit from a more complete preoperative cardiac study in these patients should be performed.

R2CHA2DS2-VA Predictsthe Cardiovascular Risk after Carotid Endarterectomy.

BACKGROUND: R2CHA2DS2-VA score has been used to predict short and long-term outcomes in many cardiovascular diseases. This study aims to validate the R2CHA2DS2-VA score as a long-term major adverse cardiovascular events (MACE) predictor after carotid endarterectomy (CEA). Secondary outcomes were also assessed regarding the incidence of all-cause mortality, acute myocardial infarction (AMI), major adverse limb events (MALE), and acute heart failure (AHF). METHODS: From January 2012 to December 2021, patients (n = 205) from a Portuguese tertiary care and referral center that underwent CEA with regional anesthesia (RA) for carotid stenosis (CS) were selected from a previously collected prospective database, and a posthoc analysis was performed. Demographics and comorbidities were registered. Clinical adverse events were assessed 30 days after the procedure and in the subsequent long-term surveillance period. Statistical analysis was performed by the Kaplan-Meier method and Cox proportional hazards regression. RESULTS: Of the patients enrolled, 78.5% were males with a mean age of 70.44 ± 8.9 years. Higher scores of R2CHA2DS2-VA were associated with long-term MACE (adjusted hazard ratio (aHR) 1.390; 95% confidence interval (CI) 1.173-1.647); and mortality (aHR 1.295; 95% CI 1.08-1.545). CONCLUSIONS: This study demonstrated the potential of the R2CHA2DS2-VA score to predict long-term outcomes, such as AMI, AHF, MACE, and all-cause mortality, in a population of patients submitted to carotid endarterectomy.

Carotid stenting: Does stent design matter?

BACKGROUND: Carotid artery stenting (CAS) is considered an important tool in carotid revascularization. Carotid artery stenting is usually performed by using self-expandable stent with different designs. The stent design influences many physical characteristics. Also, it may affect the complication rate with special relevance to perioperative stroke, hemodynamic instability, and late restenosis. METHODS: This study comprised all consecutive patients who underwent carotid artery stenting for atherosclerotic carotid stenosis from March 2014 to May 2021. Both symptomatic patient and asymptomatic patients were included. Patients with a symptomatic carotid stenosis of ≥50% or asymptomatic carotid stenosis of ≥60% were selected for carotid artery stenting . Patients with fibromuscular dysplasia and acute or unstable plaque were not included. Variables of clinical relevance were tested in multivariable analysis using binary logistic regression model. RESULTS: A total of 728 patients were enrolled. The majority of this cohort was asymptomatic (578/728, 79.4%), while 150/728 (20.6%) were symptomatic. The mean degree of carotid stenosis was 77.82 ± 4.73%, with a mean plaque length of 1.76 ± 0.55 cm. A total of 277 (38%) patients were treated with Xact® Carotid Stent System. Successful carotid artery stenting was achieved in 698 (96%) of patients. Of these patients, stroke rate in symptomatic patients was nine (5.8%), while in asymptomatic patients was 20 (3.4%). In a multivariable analysis, the open-cell carotid stent was not associated with a differential risk for combined acute and sub-acute neurologic complications as compared with closed-cell stents. Patients treated with open cell stents had a significantly lower rate of procedural hypotension (P 0.0188) at bivariate analysis. CONCLUSION: Carotid artery stenting is considered a safe alternative to CEA that can be used in selected average surgical risk patient. Different stent designs can affect the rate of major adverse events in carotid artery stenting patients, but further studies are necessary with avoiding different bias to study the effect of different stent designs.

Red Blood Cell Distribution Width Predicts Myocardial Infarction and Mortality After Vascular Surgery-A Prospective Cohort Study.

BACKGROUND: This study aims to investigate the association between preoperative Red blood cell Distribution Width (RDW) and postoperative outcomes, including myocardial infarction (MI), and mortality. METHODS: A prospective cohort including all patients submitted to elective vascular arterial surgery at a university hospital. The primary and secondary outcomes were 30-day mortality and 30-day MI, respectively. RESULTS: Atrial fibrillation, chronic kidney disease (CKD), and dependent functional status were more prevalent in deceased patients. After multivariable analysis, age (adjusted OR 1.08, 95% Confidence Interval [1.01-1.15], p = 0.027) and RDW-standard deviation (RDW-SD) (1.08 [1.01-1.16], p = 0.032) remained independent predictors of mortality. Patients with MI had higher rates of diabetes, CKD, dependent functional status, ASA physical status IV, and insulin medication. After multivariable analysis, dependent functional status (4.8 [1.6-15.0], p = 0.007), insulin medication (4.4 [1.5-12.6], p = 0.007) and RDW-SD (1.10 [1.02-1.19], p = 0.020) were independent predictors of MI. CONCLUSION: RDW-SD independently predicted postoperative MI and mortality, and may provide valuable information for prevention and early management of adverse outcomes.

Outcome Analysis Using the Modified Frailty Index-5 in Patients With Complex Aortoiliac Disease.

OBJECTIVES: Vascular surgery patients commonly have several comorbidities that cumulatively lead to a frailty status. The cumulative comorbidities disproportionately increase the risk of adverse events and are also associated with worsened long-term prognosis. In recent years, several tools have been elaborated with the objective of quantifying a patient's frailty. One of them is the modified frailty index-5 (mFI-5), a simplified and easy to use index. There is scarce data regarding its value as a prognostic factor in aortoiliac occlusive disease. The aim of this work is to validate mFI-5 as a potential postoperative prognostic indicator in this population. METHODS: From January 2013 to January 2020, 109 patients who underwent elective revascularizations, either endovascular or open surgery, having Trans-Atlantic Inter-Society Consensus II type D aortoiliac lesions in a tertiary and a regional hospital were selected from a prospective vascular registry. Demographic data was collected including diabetes mellitus, chronic heart failure, chronic obstructive pulmonary disease, arterial hypertension requiring medication and functional status. The 30-d and subsequent long-term surveillance outcomes were also collected including major adverse cardiovascular events (MACE), major adverse limb events (MALE) and all-cause mortality were assessed in the 30-d post-procedure and in the subsequent long-term surveillance period. The mFI-5 was applied to this population to evaluate the prognostic impact of this frailty marker on mortality and morbidity. RESULTS: In the long-term follow-up, mFI-5 was significantly associated with MACE (hazard ratio [HR] 2.469; 95% confidence interval [CI]: 1.267-4.811; P = .008) and all-cause mortality (HR 2.585; 95% CI: 1.270-5.260; P = .009). However, there was no significant association with 30-day outcomes. Along with the presence of chronic kidney disease, mFI-5 was the prognostic factor better able of predicting MACE. No prognostic value was found regarding short-term outcomes. CONCLUSION: The mFI-5 index may have a role in predicting long term outcomes, namely MACE and all-cause mortality, in the subset of patients with extensive aortoiliac occlusive disease. Its ease of use can foster its application in risk stratification and contribute for the decision-making process.

Mean Platelet Volume Predicts Restenosis After Carotid Endarterectomy.

BACKGROUND: Carotid restenosis following carotid endarterectomy (CEA) has a cumulative risk at 5-years up to 32%, which may impact the well-being of patients following CEA. Haematological parameters in the standard complete blood cell count (CBC) are emerging as potential biomarkers, but their application in CEA is scarce. The primary aim of this study was to investigate haematological markers for restenosis following CEA. The secondary aim was to characterize clinical risk factors for restenosis. METHODS: From January 2012 to January 2019, 151 patients who underwent CEA under regional anaesthesia due to carotid stenosis were selected from a prospectively maintained cohort database. Patients were included if a preoperative CBC was available in the 2 weeks preceding CEA. Multivariable analysis was performed alongside propensity score matching (PSM) analysis, using the preoperative CEA parameters, to reduce confounding factors between categories. RESULTS: The study group comprised 28 patients who developed carotid restenosis. The remaining 123 patients without restenosis composed the control group. Mean age of the patients did not differ significantly between groups (70.25 ± 8.05 vs. 70.32 ± 9.61 YO, P = 0.973), neither did gender (male gender 89.3% vs. 78.9%, P = 0.206). Regarding haematological parameters, only MPV remained statistically significant within multivariable analysis (1.855, aOR [1.174-2.931], P = 0.008), a result supported by PSM analysis (2.072, aOR [1.036-4.147], P = 0.042). CONCLUSIONS: MPV was able to predict restenosis 2 years after CEA. Thus, MPV can be incorporated into score calculations to identify patients at greater risk of restenosis, who could benefit from specific monitoring during follow-up. While results are promising, more research is necessary to corroborate them.

Contralateral Carotid Stenosis is a Predictor of Long-term Adverse Events in Carotid Endarterectomy.

Contralateral carotid stenosis (clCS) has been described as a perioperative predictor of mortality after carotid endarterectomy (CEA). However, its predictive value on long-term cardiovascular events remains controversial. The study aims to assess the potential role of clCS as a long-term predictor of major adverse cardiovascular events (MACE) in patients who underwent CEA. From January 2012 to July 2020, patients undergoing CEA under regional anesthesia for carotid stenosis in a tertiary care and referral center were eligible from a prospective database, and a post hoc analysis was performed. The primary outcome consisted in the occurrence of long-term MACE. Secondary outcomes included all-cause mortality, stroke, myocardial infarction, acute heart failure, and major adverse limb events. A total of 192 patients were enrolled. With a median 50 months follow-up, chronic kidney disease (CKD) (mean survival time (MST) 51.7 vs. 103.3, P < 0.010) and peripheral artery disease (PAD) (MST 75.1 vs. 90.3, P = 0.001) were associated with decreased survival time. After propensity score matching (PSM), CKD (MST 49.1 vs. 106.0, P = 0.001) and PAD (MST 75.7 vs. 94.0, P = 0.001) maintained this association. On multivariate Cox regression analysis, contralateral stenosis was associated with higher MACE (hazard ratio (HR) = 2.035; 95% CI: 1.113-3.722, P = 0.021 and all-cause mortality (HR = 2.564; 95% CI: 1.276-5,152 P = 0.008). After PSM, only all-cause mortality (HR 2.323; 95% CI: 0.993-5.431, P = 0.052) maintained a significant association with clCS. On multivariable analysis, clCS (aHR 2.367; 95% CI: 1.174-4.771, P = 0.016), age (aHR 1.039, 95% CI: 1.008-1.070), CKD (aHR 2.803; 95% CI: 1.409-5.575, P = 0.003) and PAD (aHR 3.225, 95% CI: 1.695-6.137, P < 0.001) were independently associated with increased all-cause mortality. Contrary to MACE, clCS is a strong predictor of long-term all-cause mortality after CEA. However, MACE risk may compromise CEA benefits by other competitive events. Therefore, further studies are needed to establish the role of clCS on postoperative events and on patients' specific assessments in order to determine the best medical treatment and easy access to surgical intervention.

Revised cardiac score index is a predictor of long-term outcomes after carotid endarterectomy.

Background: Cardiac complications represent the main cause of mortality after non-cardiac surgery and the Revised Cardiac Risk Index (RCRI) was created to estimate the perioperative risk of these events. It considers history of ischaemic heart disease, congestive heart failure, diabetes requiring preoperative insulin, stroke or transient ischaemic attack and renal impairment. We aim to describe the accuracy of the RCRI for predicting perioperative major adverse cardiovascular events (MACE) - a composite of heart failure, ischemic events and all-cause death. Also, the authors aimed to review the score for better prediction of cardiovascular outcomes. Patients and methods: From January 2012 to January 2020, patients who underwent Carotid endarterectomy (CEA) with regional anaesthesia (RA) were selected. RCRI was calculated for each case. Estimated and reported cardiovascular complications were compared using multivariate logistic regression and cox proportional hazards. An alternative and optimized carotid-RCRI (CtRCRI) was obtained. Overall predictive accuracy was assessed and compared by measuring model discrimination. Adjustments for overfitting and evaluation of the new model were performed by bootstrap. Results: 186 patients were selected, of which 80% were male with a mean age of 70.0±9.05 years old. The median follow-up was 50 months, interquartile range 21-69 months. None of the scores were able to predict MACE in the perioperative period. Both were associated with 30-day Clavien-Dindo ≥2 (p=0.022 and p=0.041, respectively). Regarding long-term prognosis, both were able to predict MACE (RCRI: hazard ratio (HR) 3.54 (95% confidence interval [CI] 1.04-11.48) vs. CtRCRI: HR 2.08 (95%CI 1.08-3.98) and all-cause mortality (RCRI: HR 3.33, 95%CI 0.99-11.11 vs. CtRCRI: HR 1.57, 95%CI 1.14-7.04). Conclusions: RCRI and CtRCRI did not predict MACE in the perioperative period but are good predictors of 30-day complications (Clavien-Dindo ≥2). Both RCRI and CtRCRI have good prognostic value as predictors of long-term cardiovascular events.

The Diagnostic Accuracy of Intra-Operative Near Infrared Spectroscopy in Carotid Artery Endarterectomy Under Regional Anaesthesia: Systematic Review and Meta-Analysis.

OBJECTIVE: Intra-operative near infrared spectroscopy (NIRS) is a non-invasive tool used to monitor regional cerebral oxygen saturation during carotid endarterectomy (CEA), for which accuracy remains unclear. Therefore, this systematic review and meta-analysis aimed to determine the diagnostic accuracy of NIRS in patients undergoing CEA under regional anaesthesia (RA). DATA SOURCES: MEDLINE, Scopus, and Web of Science were searched for studies that compared NIRS with the "awake test" in patients undergoing CEA under RA. REVIEW METHODS: Bivariable random effects meta-analysis was performed to determine the diagnostic accuracy of NIRS to detect cerebral ischaemia. Meta-regression was performed to explore causes of heterogeneity. Meta-analysis of proportions was also performed to determine the accuracy of NIRS in predicting 30 day stroke. Study quality was evaluated using the QUADAS-2 criteria. RESULTS: Eleven primary studies were included, assessing 1 237 participants. The meta-analysis obtained a partial area under the summary receiver operating characteristic curve for diagnosing brain ischaemia of 0.646, with a summary sensitivity of 72.0% (95% confidence interval [CI] 58.1 - 82.7; I2 = 48.6%) and a specificity of 84.1% (95% CI 78.5-88.4; I2 = 48.6%). In meta-regression analysis, the frequency of hypertension (p = .011) and patients with symptomatic carotid stenosis (p = .031) were significant effect modifiers. Higher frequency of arterial hypertension (z score = -2.15; p = .032) and diabetes (z score = -2.12; p = .034) were associated with lower summary sensitivity, while a higher frequency of symptomatic carotid stenosis (z score = 2.11; p = .035) was associated with higher summary sensitivity. Point estimate sensitivity and specificity for predicting 30 day stroke occurrence were 41% (95% CI 19.5 - 66.6; I2 = 0%) and 81.4% (95% CI 74.4 - 86.9, I2 = 65.6%), respectively. CONCLUSION: The results of this study suggest that NIRS as a cerebral monitoring technique does not have sufficiently high sensitivity or specificity to be used alone in the neurological monitoring of patients undergoing CEA under RA.

Impact of oral anticoagulation therapy on postoperative atrial fibrillation outcomes: a systematic review and meta-analysis.

BACKGROUND: Post-operative atrial fibrillation (POAF) is the most common complication after cardiac surgery. Recent studies had shown this phenomenon is no longer considered transitory and is associated with higher risk of thromboembolic events or death. The aim of this study was to systematically review and analyze previous studies comparing oral anticoagulation therapy with no anticoagulation, regarding these long-term outcomes. METHODS: PubMed/MEDLINE, EMBASE, Web of Science and Cochrane Database were systematically searched to identify the studies comparing the risk of stroke, or thromboembolic events or mortality of POAF patients who received anticoagulation compared with those who were not anticoagulated. Incidence of stroke, thromboembolic events and all-cause mortality were evaluated up to 10 years after surgery. Time-to-event outcomes were collected through hazard ratio (HR) along with their variance and the early endpoints using frequencies or odds ratio (OR). Random effect models were used to compute statistical combined measures and 95% confidence intervals (CI). Heterogeneity was evaluated through Q statistic-related measures of variance (Tau2, I2, Chi-squared test). RESULTS: Eight observational cohort studies were selected, including 15,335 patients (3492 on Oral Anticoagulants (OAC) vs 11,429 without OAC) that met the inclusion criteria for qualitative synthesis. Patients had a wide gender distribution (38.6-82.3%), each study with a mean age above 65 years (67.5-85). Vitamin K antagonists were commonly prescribed anticoagulants (74.3-100%). OAC was associated with a protective impact on all-cause mortality at a mean of 5.0 years of follow-up (HR is 0.85 [0.72-1.01]; p = 0.07; I2 = 48%). Thromboembolic events did not differ between the two treatment arms (HR 0.68 [0.40-1.15], p = 0.15). CONCLUSION: Current literature suggests a possibly protective impact of OAC therapy for all-cause mortality in patients with new-onset atrial fibrillation after cardiac surgery. However, it does not appear to impact thromboembolism rate.

Impact of intraoperative neurologic deficits in carotid endarterectomy under regional anesthesia.

OBJECTIVE: Patients undergoing carotid endarterectomy (CEA) may experiment neurologic deficits during the carotid cross-clamping due to secondary cerebral hypoperfusion. An associated risk of postoperative stroke incidence is also well established. This work aimed to assess the postoperative adverse events related to neurologic deficits in the awake test after clamping and to determine its predictive factors. Methods. From January 2012 to January 2018, 79 patients from a referral hospital that underwent CEA with regional anesthesia for carotid stenosis and manifested neurologic deficits were gathered. Consecutively selected controls (n = 85) were submitted to the same procedure without developing neurological changes. Postoperative complications such as stroke, myocardial infarction, all-cause death, and Clavien-Dindo classification were assessed 30 days after the procedure. Univariate and binary logistic regressions were performed for data assessment. Results. Patients with clamping associated neurologic deficits were significantly more obese than the control group (aOR = 9.30; 95% CI: 2.57-33.69; p = .01). Lower degree of ipsilateral stenosis and higher degree of contralateral stenosis were independently related to clamping intolerance (aOR = 0.70; 95% CI: 0.49-0.99; p = .047 and aOR = 1.30; 95% CI: 1.06-1.50; p = .009, respectively). Neurologic deficits were a main 30-day stroke predictor (aOR = 4.30; 95% CI: 1.10-16.71; p = .035). Conclusions. Neurologic deficits during carotid clamping are a predictor of perioperative stroke. Body mass index > 30 kg/m2, a lower degree of ipsilateral stenosis, and a higher degree of contralateral stenosis are independent predictors of neurologic deficits and, therefore, might play a role in the prevention of procedure-related stroke.

Impact of Gradual Adoption of EVAR in Elective Repair of Abdominal Aortic Aneurysm: A Retrospective Cohort Study from 2009 to 2015.

INTRODUCTION: The recommendations about the preferred type of elective repair of abdominal aortic aneurysm (AAA) still divides guidelines committees, even nowadays. The aim is to assess outcomes after AAA repair focusing on differences between endovascular aneurysm repair (EVAR) and open surgical repair (OSR). METHODS: The observational retrospective cohort study of consecutive patients submitted to elective AAA repair at a tertiary center, 2009-2015. Exclusion criteria were as follows: nonelective cases or complex aortic aneurysms. Primary outcomes were postoperative complications, length of hospital stay, survival, freedom from aortic-related mortality, and vascular reintervention. Time trends were assessed along the period under analysis. RESULTS: From a total of 211 included patients, those submitted to EVAR were older (74 ± 7 vs. 67 ± 9 years; P < 0.001), presented a higher prevalence of hypertension (83.5% vs. 68.5%, P = 0.004), obesity (28.7% vs. 14.3%, P = 0.029), previous cardiac revascularization (30.5% vs. 14.7%, P = 0.005), heart failure (17.2% vs. 5.2%, P = 0.013), and chronic obstructive pulmonary disease (32.8% vs. 13.3%, P = 0.002). Patients were followed during a median of 49 months. EVAR resulted in a significantly shorter length of hospital stay (median 4 and interquartile range 3 vs. 8 (9); P < 0.001), lower 30-day complications (10.6% vs. 22.8%, P = 0.017), lower aortic-related mortality, and similar reintervention after adjustment with a propensity score. Along the time under analysis, EVAR became the predominate type of repair (P = 0.024), the proportion of complications decreased (P = 0.014), and the 30-day mortality (P = 0.035). CONCLUSIONS: Although EVAR was offered to patients with more comorbidities, better and durable outcomes were achieved after EVAR, favoring its adoption for elective AAA repair.

Benefit of selective shunt use during carotid endarterectomy under regional anesthesia.

OBJECTIVES: Carotid cross-clamping during endarterectomy exposes the patient to intraoperative neurological deficits due to embolism or cerebral hypoperfusion. To prevent further cerebrovascular incidents, resorting to shunt is frequently recommended. However, since this method is also considered a stroke risk factor, the use is still controversial. This study aims to shed some light on the best approach regarding the use of shunt in symptomatic cerebral malperfusion after carotid artery cross-clamping. METHODS: From January 2012 to January 2018, 79 patients from a tertiary referral hospital who underwent carotid endarterectomy with regional anesthesia for carotid artery stenosis and manifested post-clamping neurologic deficits were prospectively gathered. Shunt use was left to the decision of the surgeon and performed in 31.6% (25) of the patients. Demographics, comorbidities, imaging tests, and clinical/intraoperative features were evaluated. For data assessment, univariate analysis was performed. RESULTS: Regarding 30-day stroke, 30-day postoperative complications (stroke, surgical hematoma, hyperperfusion syndrome), and cranial nerve injury, no significant differences were found (P = 0.301, P = 0.460, and P = 0.301, respectively) between resource to shunt and non-shunt. Clamping and surgery times were significantly higher in the shunt group (P < 0.001 and P = 0.0001, respectively). CONCLUSIONS: Selective-shunting did not demonstrate superiority for patients who developed focal deficits regarding stroke or other postoperative complications. However, due to the limitations of this study, the benefit of shunting cannot be excluded. Further randomized trials are recommended for precise results on this matter with current sparse clinical evidence.

Efficacy of near-infrared spectroscopy cerebral oximetry on detection of critical cerebral perfusion during carotid endarterectomy under regional anesthesia.

Background: Patients undergoing carotid endarterectomy (CEA) may suffer from cerebral hypoperfusion during the carotid cross-clamping. Near-infrared spectroscopy cerebral oximetry (NIRS) is a non-invasive method of regional cerebral oxygen saturation measurement reflecting changes in cerebral blood flow during CEA. The main goal of the study was to evaluate the accuracy of the NIRS in detecting cerebral hypoperfusion during CEA under regional anesthesia (RA) and compare it with awake neurological testing. Patients and methods: A prospective observational study of 28 patients that underwent CEA in RA and manifested neurologic deficits, and 28 consecutive controls from a tertiary and referral center, was performed. All patients were monitored with NIRS cerebral oximetry and awake testing as the control technique. Subsequently, operating characteristic curve and Cohen's kappa coefficient were determined to evaluate the reliability of the monitoring test. Results: NIRS presented a sensitivity of 27.3% and a specificity of 89.3% in comparison to awake testing. Receiver operating characteristic (ROC) curve analysis demonstrated that a decrease of at least 20% in cerebral oxygen saturation is the best threshold to infer cerebral hypoperfusion. However, the respective area under the curve (AUROC) was 0.606 (95% CI: 0.456-0.756, P = 0.178) with a calculated Cohen's kappa of 0.179, P = 0.093. Regarding 30-days outcomes, only awake testing has shown significant associations with stroke and postoperative complications (P = 0.043 and P = 0.05), which were higher in patients with post-clamping neurologic deficits. Conclusions: NIRS demonstrated a reduced discriminative capacity for critical cerebral hypoperfusion, and does not seem to add substantial clinical benefits to the awake test.

Computational analysis of the SARS-CoV-2 and other viruses based on the Kolmogorov's complexity and Shannon's information theories.

This paper tackles the information of 133 RNA viruses available in public databases under the light of several mathematical and computational tools. First, the formal concepts of distance metrics, Kolmogorov complexity and Shannon information are recalled. Second, the computational tools available presently for tackling and visualizing patterns embedded in datasets, such as the hierarchical clustering and the multidimensional scaling, are discussed. The synergies of the common application of the mathematical and computational resources are then used for exploring the RNA data, cross-evaluating the normalized compression distance, entropy and Jensen-Shannon divergence, versus representations in two and three dimensions. The results of these different perspectives give extra light in what concerns the relations between the distinct RNA viruses.