Clinical outcomes of transcarotid artery revascularization vs carotid endarterectomy from a large single-center experience

BACKGROUND

Transcarotid artery revascularization (TCAR) has been practiced as an alternative for both carotid endarterectomy (CEA) and transfemoral carotid artery stenting, specifically in high-risk patients. More recently, the Centers for Medicare and Medicaid Services expanded coverage for TCAR in standard surgical risk patients if done within the Society for Vascular Surgery Vascular Quality Initiative TCAR surveillance project. A few registry studies (primarily from the Society for Vascular Surgery Vascular Quality Initiative) compared the early and up to 1-year outcomes of TCAR vs CEA or transfemoral carotid artery stenting. There is no large single-center study that reported late clinical outcomes. The present study compares intermediate clinical outcomes of TCAR vs CEA.

METHODS

This study retrospectively analyzed collected data from TCAR surveillance project patients enrolled in our institution and compare it with CEA patients done by the same providers at the same time period. The primary outcome was combined perioperative stroke/death and late stroke/death. Secondary outcomes included combined stroke, death, and myocardial infarction, cranial nerve injury (CNI), and bleeding. Propensity matching was done to analyze outcome. Kaplan-Meier analysis was used to estimate freedom from stroke, stroke/death, and ≥50% and ≥80% restenosis.

RESULTS

We analyzed 646 procedures (637 patients) (404 CEA, 242 TCAR). There was no significant difference in the indications for carotid intervention. However, TCAR patients had more high-risk criteria, including hypertension, coronary artery disease, congestive heart failure, and renal failure. There was no significant differences between CEA vs TCAR in 30-day perioperative stroke (1% vs 2%), stroke/death rate (1% vs 3%; P = .0849), or major hematomas (2% vs 2%). The rate of CNI was significantly different (5% for CEA vs 1% for TCAR; P = .0138). At late follow-up (2 years), the rate of stroke was 1% vs 4% (P = .0273), stroke/death 8% vs 15% (P = .008), ≥80 % restenosis 0.5% vs 3% (P = .0139) for CEA patients vs TCAR patients, respectively. After matching 242 CEAs and 242 TCARs, the perioperative stroke rate was 1% for CEA vs 2% for TCAR (P = .5037), the stroke/death rate was 2% vs 3% (P = .2423), and the CNI rate was 3% vs 1% (P = .127). At late follow-up, rates of stroke were 1% for CEA vs 4% for TCAR (P = .0615) and stroke/death were 8% vs 15% (P = .0345). The rate of ≥80% restenosis was 0.9% for CEA vs 3% for TCAR (P = .099). The rates of freedom from stroke at 6, 12, 18, and 24 months for CEA vs TCAR were 99%, 99%, 99%, and 99% vs 97%, 95%, 93% and 93%, respectively (P = .0806); stroke/death were 94%, 90%, 87%, and 86% vs 93%, 87%, 76%, and 75%, respectively (P = .0529); and ≥80% restenosis were 100%, 99%, 98%, and 98% vs 97%, 95%, 93%, and 93%, respectively (P = .1132).

CONCLUSIONS

In a propensity-matched analysis, both CEA and TCAR have similar perioperative clinical outcomes. However, CEA was superior to TCAR for the rates of late stroke/death and had a somewhat lower rate of ≥80% restenosis at 2 years, but this difference was not statistically significant.

A single-center experience of 30-day perioperative and one year clinical outcomes of transcarotid artery revascularization in 100 consecutive patients

BACKGROUND

Transcarotid Artery Revascularization (TCAR) using the ENROUTE system (Silk Road) has been proposed as a safe and effective alternative to both carotid endarterectomy (CEA) and transfemoral carotid artery stenting (TF-CAS). Two large registries (ROADSTER 1 and ROADSTER 2) have shown that TCAR has acceptable/low rates of perioperative stroke/death. This study will analyze the 30-day perioperative and 1-year clinical outcomes from a single-center.

PATIENT POPULATION AND METHODS

This is a retrospective analysis of prospectively collected data from SVS/VQI TCAR surveillance project (TSP) of 100 consecutive patients (102 TCAR procedures) done in our institution. These procedures were done for high-risk patients for CEA, which included anatomical (previous CEA, high cervical lesion, neck radiation, stoma, arch type, etc.), physiological (CHF, severe coronary artery disease, COPD on O2 therapy, etc.) and combined anatomical/physiological reasons. These procedures were done by vascular surgeons after receiving the appropriate training. The perioperative stroke, death, and MI rates were analyzed. Kaplan Meyer analysis was used to estimate rate of freedom from stroke/death and the incidence of ≥50% and ≥80% in-stent restenosis at 1 year.

RESULTS

100 consecutive high-risk patients for CEA included: 38% anatomical, 44% physiological, and 18% combined anatomical and physiological reasons. The mean age was 72.5 years (range 52-90 years). Indications for TCAR were 34% for symptomatic lesions (TIA/stroke) and 66% for asymptomatic lesions. Mean ipsilateral treated stenosis was 80.4%. Contralateral ≥50% stenosis/occlusion was present in 31% of patients. Technical success rate was 100%. 92% had pre-stenting PTA and 26% had post-stenting PTA. The mean flow reversal time was 8.5 min (range 3-26 min). The 30-day perioperative stroke rate was 2.9% (1/67, 1.5% for asymptomatic patients), the stroke/death rate was 2.9%, and stroke/death and MI rate was 3.9% (4/102). Other perioperative complications included cranial nerve injury 3/102 (2.9%), carotid artery dissection (2%), and major hematoma (necessitated operation evacuation) (5.9%). Freedom from stroke rates and stroke/death rates at 1 year were: 90% and 89%. Freedom from ≥50% and ≥80% in-stent restenosis rates at 1 year were 82% and 90%, respectively. None of these restenosis were symptomatic except two (2/13). Freedom from reintervention rate at 1 year was 98%.

CONCLUSION

Although the perioperative events were somewhat higher than what has been reported in previous registries, TCAR for patients who are high-risk for CEA has a low perioperative stroke and stroke/death rates with satisfactory outcome at 1 year. Further long-term data is probably needed to verify long-term outcome.

Long-term durability and clinical outcome of a prospective randomized trial comparing carotid endarterectomy with ACUSEAL polytetrafluoroethylene patching versus pericardial patching

BACKGROUND

Several studies have shown the superiority of carotid endarterectomy (CEA) with patch closure over primary closure. However, no definite study has shown any significant differences in clinical outcome between various types of patches. Because more vascular surgeons have used pericardial patching recently, this study will analyze the late clinical outcome (≥10 years) of our previously reported prospective randomized trial comparing CEA with ACUSEAL (polytetrafluoroethylene) vs pericardial patching.

METHODS

A total of 200 CEAs were randomized (1:1) to either Vascu-Guard pericardial patching or ACUSEAL patching. All patients had immediate duplex ultrasound imaging, which was repeated at 6 months and annually thereafter. Kaplan-Meier analysis was used to estimate rates of freedom from stroke, stroke-free survival, and rates of freedom from ≥50% and ≥80% restenosis.

RESULTS

Overall demographic and clinical characteristics were somewhat similar with a mean follow-up of 80 months (range: 0-149 months). The rates of freedom from stroke were 97, 97, 97, 96, 93 for ACUSEAL vs 99, 98, 97, 97, 92 for pericardial patching (P = .1112) at 1, 2, 3, 5, and 10 years, respectively. Similarly, the rates of freedom from stroke/death were 94, 93, 90, 76, 50 for ACUSEAL vs 99, 96, 91, 78, 47 for pericardial patching (P = .8591). The rates of freedom from ≥50% restenosis were 98, 98, 96, 89, 79 for ACUSEAL vs 87, 83, 83, 81, 71 for pericardial patching (P = .0489). The rates of freedom from ≥80% restenosis were 99, 99, 99, 96, 85 for ACUSEAL vs 96, 96, 96, 93, 93 for pericardial patching (P = .9407). The overall survival rates were 95, 94, 91, 77, 51 for ACUSEAL vs 100, 98, 93, 79, 50 for pericardial patching (P = .9123). Other patch complications (eg, rupture, aneurysmal dilation, infection, etc) were similar.

CONCLUSIONS

Both CEA with ACUSEAL (polytetrafluoroethylene) and pericardial patching are durable and have similar clinical outcomes at 10 years except that ACUSEAL patching has significantly better rates of freedom from ≥50% restenosis.

Thirty-Day Perioperative Clinical Outcomes of Transcarotid Artery Revascularization vs Carotid Endarterectomy in a Single-Center Experience

BACKGROUND

Transcarotid artery revascularization (TCAR) has been proposed as a alternative to carotid endarterectomy (CEA) and transfemoral carotid artery stenting in high-risk patients. Recently Centers for Medicare and Medicaid Services expanded coverage for TCAR to include standard surgical risk patients within the Society of Vascular Surgery Vascular Quality Initiative TCAR Surveillance Project. Few single centers compared the clinical outcome of TCAR with CEA. This study compares 30-day perioperative clinical outcomes between TCAR and CEA.

STUDY DESIGN

This is retrospective analysis of prospectively collected data from the TCAR Surveillance Project of TCAR patients enrolled in our institution and compared with CEAs done in the same time/with the same providers. The primary outcome was stroke and/or death. Secondary outcomes included stroke, death, MI, cranial nerve injury, bleeding, and others. Propensity matching was done to analyze outcomes.

RESULTS

The study analyzed 501 patients (347 CEA, 154 TCAR). There were no significant differences in symptomatic status (43% for CEA vs 38% for TCAR, p = 0.303). TCAR had more patients with hypertension (p = 0.04), coronary artery disease (p = 0.028), and congestive heart failure (p = 0.039). The 30-day perioperative complication rates for CEA vs TCAR were as follows: stroke 1% vs 3% (p = 0.142), stroke/death 1% vs 3% (p = 0.185), MI 0.6% vs 0.7% (p = 1), death 0.6% vs 0% (p = 1), stroke/death/MI 2% vs 4% (p = 0.233), cranial nerve injury 4% vs 2% (p = 0.412), and major hematoma (requiring reintervention) 2% vs 3% (p = 1). After matching 154 CEA patients and 154 TCAR, 30-day perioperative complication rates were as follows: stroke 2% vs 3% (p = 0.723), stroke/death 3% vs 3% (p = 1), death 1.3% vs 0% (p = 0.498), MI 0.7% vs 0.7% (p = 1), and stroke/death/MI 3% vs 4% (p = 0.759).

CONCLUSIONS

This study showed that using propensity match analysis, both CEA and TCAR have similar 30-day perioperative outcomes. Further long-term data are needed.

The disturbed redox-balance in pulmonary fibrosis is modulated by the plant flavonoid quercetin

Idiopathic pulmonary fibrosis (IPF) is characterized by a disturbed pulmonary redox balance associated with inflammation. To restore this balance, antioxidants are often suggested as therapy for IPF but previous clinical trials with these compounds and their precursors have not been successful in the clinic. The exogenous antioxidant quercetin, which has a versatile antioxidant profile and is effective in restoring a disturbed redox balance, might be a better candidate. The aim of this study was to evaluate the protective effect of quercetin on oxidative and inflammatory markers in IPF. Here, we demonstrate that IPF patients have a significantly reduced endogenous antioxidant defense, shown by a reduced total antioxidant capacity and lowered glutathione and uric acid levels compared to healthy controls. This confirms that the redox balance is disturbed in IPF. Ex vivo incubation with quercetin in blood of both IPF patients and healthy controls reduces LPS-induced production of the pro-inflammatory cytokines IL-8 and TNFα. This anti-inflammatory effect was more pronounced in the blood of the patients. Our pro-fibrotic in vitro model, consisting of bleomycin-triggered BEAS-2B cells, shows that quercetin boosts the antioxidant response, by increasing Nrf2 activity, and decreases pro-inflammatory cytokine production in a concentration-dependent manner. Collectively, our findings implicate that IPF patients may benefit from the use of quercetin to restore the disturbed redox balance and reduce inflammation.

Effect of interleukin (IL)-8 on benzo[a]pyrene metabolism and DNA damage in human lung epithelial cells

It has been well established that inflammation and concurrent mutagenic exposures drive the carcinogenic process in a synergistic way. To elucidate the role of the inflammatory cytokine IL-8 in this process, we studied its effect on the activation and deactivation of the chemical mutagen benzo[a]pyrene B[a]P in the immortalized pulmonary BEAS-2B cell line. After 24h incubation with B[a]P in the presence or absence of IL-8, the B[a]P induced cytochrome P450 1A1 and 1B1 (CYP1A1 and CYP1B1) gene expression and CYP1A1 enzyme activity was significantly higher in the presence of the cytokine. Consistent with these findings, we observed higher concentration of the metabolite B[a]P-7,8-diol under concurrent IL-8 treatment conditions. Interestingly, we also found higher concentrations of unmetabolized B[a]P. To explain this, we examined the downstream effects of IL-8 on NADPH oxidases (NOXes). IL-8 lowered the intracellular NADPH level, but this effect could not explain the changes in B[a]P metabolism. IL-8 also significantly depleted intracellular glutathione (GSH), which also resulted in enhanced levels of unmetabolized B[a]P, but increased concentrations of the metabolite B[a]P-7,8-diol. No differences in B[a]P-DNA adducts level were found between B[a]P and B[a]P combined with IL-8, and this might be due to a 3-fold increase in nucleotide excision repair (NER) after IL-8 treatment. These findings suggest that IL-8 increased the formation of B[a]P-7,8-diol despite an overall delayed B[a]P metabolism via depletion of GSH, but DNA damage levels were unaffected due to an increase in NER capacity.

A Novel Strategy for Attenuating Opioid Withdrawal in Neonates

The rate of Neonatal Abstinence Syndrome (NAS) has drastically increased over the past decade. The average hospital expense per NAS patient has tripled, while the number of babies born to opioid-dependent mothers has increased to 5 in 1000 births. Current treatment options are limited to opioid replacement and tapering. Consequently, we examined the efficacy of prenatal, low-dose and short-term vigabatrin (γ-vinyl GABA, GVG) exposure for attenuating these symptoms as well as the metabolic changes observed in the brains of these animals upon reaching adolescence. Pregnant Sprague-Dawley rats were treated in one of four ways: 1) saline; 2) morphine alone; 3) morphine+GVG at 25 mg/kg; 4) morphine+GVG at 50 mg/kg. Morphine was administered throughout gestation, while GVG administration occurred only during the last 5 days of gestation. On post-natal day 1, naloxone-induced withdrawal behaviours were recorded in order to obtain a gross behaviour score. Approximately 28 days following birth, ¹⁸FDG microPET scans were obtained on these same animals (Groups 1, 2, and 4). Morphine-treated neonates demonstrated significantly higher withdrawal scores than saline controls. However, GVG at 50 but not 25 mg/kg/day significantly attenuated them. Upon reaching adolescence, morphine treated animals showed regionally specific changes in ¹⁸FDG uptake. Again, prenatal GVG exposure blocked them. These data demonstrate that low-dose, short-term prenatal GVG administration blocks naloxone-induced withdrawal in neonates. Taken together, these preliminary findings suggest that GVG may provide an alternative and long-lasting pharmacologic approach for the management of neonatal and adolescent symptoms associated with NAS.

Acidic cellular microenvironment modifies carcinogen-induced DNA damage and repair

Chronic inflammation creates an acidic microenvironment, which plays an important role in cancer development. To investigate how low pH changes the cellular response to the carcinogen benzo[a]pyrene (B[a]P), we incubated human pulmonary epithelial cells (A549 and BEAS-2B) with nontoxic doses of B[a]P using culturing media of various pH’s (extracellular pH (pH_e) of 7.8, 7.0, 6.5, 6.0 and 5.5) for 6, 24 and 48 h. In most incubations (pH_e 7.0–6.5), the pH in the medium returned to the physiological pH 7.8 after 48 h, but at the lowest pH (pH_e < 6.0), this recovery was incomplete. Similar changes were observed for the intracellular pH (pH_i). We observed that acidic conditions delayed B[a]P metabolism and at t = 48 h, and the concentration of unmetabolized extracellular B[a]P and B[a]P-7,8-diol was significantly higher in acidic samples than under normal physiological conditions (pH_e 7.8) for both cell lines. Cytochrome P450 (CYP1A1/CYP1B1) expression and its activity (ethoxyresorufin-O-deethylase activity) were repressed at low pH_e after 6 and 24 h, but were significantly higher at t = 48 h. In addition, a DNA repair assay showed that the incision activity was ~80% inhibited for 6 h at low pH_e and concomitant exposure to B[a]P. However, at t = 48 h, the incision activity recovered to more than 100% of the initial activity observed at neutral pH_e. After 48 h, higher B[a]P-DNA adduct levels and γ-H2AX foci were observed at low pH samples than at pH_e 7.8. In conclusion, acidic pH delayed the metabolism of B[a]P and inhibited DNA repair, ultimately leading to increased B[a]P-induced DNA damage.

Inflammation-associated extracellular β-glucuronidase alters cellular responses to the chemical carcinogen benzo[a]pyrene

Neutrophils infiltrate tissues during inflammation, and when activated, they release β-glucuronidase. Since inflammation is associated with carcinogenesis, we investigated how extracellular β-glucuronidase changed the in vitro cellular response to the chemical carcinogen benzo(a)pyrene (B[a]P). For this we exposed human liver (HepG2) and lung (A549) cells to B[a]P in the presence or absence of β-glucuronidase. β-Glucuronidase reduced B[a]P-induced expression of CYP1A1 and CYP1B1 at 6 h after exposure, which did not depend on β-glucuronidase activity, because the inhibitor D-saccharic acid 1,4-lactone monohydrate did not antagonize the effect of β-glucuronidase. On the other hand, the inhibitory effect of β-glucuronidase on CYP expression was dependent on signalling via the insulin-like growth factor receptor (IGF2R, a known receptor for β-glucuronidase), because co-incubation with the IGF2R inhibitor mannose-6-phosphate completely abolished the effect of β-glucuronidase. Extracellular β-glucuronidase also reduced the formation of several B[a]P metabolites and B[a]P-DNA adducts. Interestingly, at 24 h of exposure, β-glucuronidase significantly enhanced CYP expression, probably because β-glucuronidase de-glucuronidated B[a]P metabolites, which continued to trigger the aryl hydrocarbon receptor (Ah receptor) and induced expression of CYP1A1 (in both cell lines) and CYP1B1 (in A549 only). Consequently, significantly higher concentrations of B[a]P metabolites and DNA adducts were found in β-glucuronidase-treated cells at 24 h. DNA adduct levels peaked at 48 h in cells that were exposed to B[a]P and treated with β-glucuronidase. Overall, these data show that β-glucuronidase alters the cellular response to B[a]P and ultimately enhances B[a]P-induced DNA adduct levels.

Hypoxia- or PDGF-BB-dependent paxillin tyrosine phosphorylation in pulmonary hypertension is reversed by HIF-1α depletion or imatinib treatment

Chronic exposure to hypoxia induces a pronounced remodelling of the pulmonary vasculature leading to pulmonary hypertension (PH). The remodelling process also entails increased proliferation and decreased apoptosis of pulmonary arterial smooth muscle cells (PASMC), processes regulated by the cytoskeletal protein paxillin. In this study, we aimed to examine the molecular mechanisms leading to deregulation of paxillin in PH. We detected a time-dependent increase in paxillin tyrosine 31 (Y31) and 118 (Y118) phosphorylation following hypoxic exposure (1 % O2) or platelet-derived growth factor (PDGF)-BB stimulation of primary human PASMC. In addition, both, hypoxia- and PDGF-BB increased the nuclear localisation of phospho-paxillin Y31 as indicated by immunofluorescence staining in human PASMC. Elevated paxillin tyrosine phosphorylation in human PASMC was attenuated by hypoxia-inducible factor (HIF)-1α depletion or by treatment with the PDGF-BB receptor antagonist, imatinib. Moreover, we observed elevated paxillin Y31 and Y118 phosphorylation in the pulmonary vasculature of chronic hypoxic mice (21 days, 10 % O2) which was reversible by imatinib-treatment. PDGF-BB-dependent PASMC proliferation was regulated via the paxillin-Erk1/2-cyclin D1 pathway. In conclusion, we suggest paxillin up-regulation and phosphorylation as an important mechanism of vascular remodelling underlying pulmonary hypertension.

Clinically driven design of multi-scale cancer models: the ContraCancrum project paradigm

The challenge of modelling cancer presents a major opportunity to improve our ability to reduce mortality from malignant neoplasms, improve treatments and meet the demands associated with the individualization of care needs. This is the central motivation behind the ContraCancrum project. By developing integrated multi-scale cancer models, ContraCancrum is expected to contribute to the advancement of in silico oncology through the optimization of cancer treatment in the patient-individualized context by simulating the response to various therapeutic regimens. The aim of the present paper is to describe a novel paradigm for designing clinically driven multi-scale cancer modelling by bringing together basic science and information technology modules. In addition, the integration of the multi-scale tumour modelling components has led to novel concepts of personalized clinical decision support in the context of predictive oncology, as is also discussed in the paper. Since clinical adaptation is an inelastic prerequisite, a long-term clinical adaptation procedure of the models has been initiated for two tumour types, namely non-small cell lung cancer and glioblastoma multiforme; its current status is briefly summarized.

Infratentorielle Tumoren

This article gives an overview concerning the typical infratentorial tumors of adults.

Electroneutral uptake and electrogenic secretion of a fluorescent bile salt by rat hepatocyte couplets

The role of membrane voltage as a driving force for the hepatic uptake and secretion of fluorescent bile salts has been examined in isolated hepatocyte couplets. The present study demonstrates that the fluorescent bile salt derivative (N-[7-(nitrobenz-2-oxa- 1,3-diazol-4-yl)]-7-amino-3 alpha, 12 alpha-dihydroxy-5-cholan-24-oyl)-2-aminoethanesulfonate (7 beta-NBD-NCT) is taken up into hepatocytes by a saturable process with a Kt of 2.7 microM. Uptake rate was reduced by only 22% after total Na+ replacement and was independent of transmembrane potential difference over a range of -135 to +25 mV. In contrast, secretion into the canalicular space was strongly dependent on membrane voltage over the range from -34 to 0 mV in a manner consistent with electrodiffusion of an anion. Fitting the secretion time course to that predicted by electrodiffusion demonstrated that only approximately 50% of total secretion can result from electrodiffusion. Studies in isolated perfused liver confirmed this observation that depolarization caused a decrease in bile salt secretion rate. These results demonstrate that 7 beta-NBD-NCT is transported by a neutral uptake process at the sinusoidal membrane and is secreted across the canalicular membrane in part by electrogenic transport. This suggests that voltage changes could be a common pathway resulting in impaired organic anion secretion in diverse cholestatic syndromes.