[Clinical and genetic characteristics of young patients with myeloproliferative neoplasms]

Objectives: To investigate the clinical and genetic features of young Chinese patients with myeloproliferative neoplasms (MPN). Methods: In this cross-sectional study, anonymous questionnaires were distributed to patients with MPN patients nationwide. The respondents were divided into 3 groups based on their age at diagnosis: young (≤40 years) , middle-aged (41-60 years) , and elderly (>60 years) . We compared the clinical and genetic characteristics of three groups of MPN patients. Results: 1727 assessable questionnaires were collected. There were 453 (26.2%) young respondents with MPNs, including 274 with essential thrombocythemia (ET) , 80 with polycythemia vera (PV) , and 99 with myelofibrosis. Among the young group, 178 (39.3%) were male, and the median age was 31 (18-40) years. In comparison to middle-aged and elderly respondents, young respondents with MPN were more likely to present with a higher proportion of unmarried status (all P<0.001) , a higher education level (all P<0.001) , less comorbidity (ies) , fewer medications (all P<0.001) , and low-risk stratification (all P<0.001) . Younger respondents experienced headache (ET, P<0.001; PV, P=0.007; MF, P=0.001) at diagnosis, had splenomegaly at diagnosis (PV, P<0.001) , and survey (ET, P=0.052; PV, P=0.063) . Younger respondents had fewer thrombotic events at diagnosis (ET, P<0.001; PV, P=0.011) and during the survey (ET, P<0.001; PV, P=0.003) . JAK2 mutations were found in fewer young people (ET, P<0.001; PV, P<0.001; MF, P=0.013) ; however, CALR mutations were found in more young people (ET, P<0.001; MF, P=0.015) . Furthermore, mutations in non-driver genes (ET, P=0.042; PV, P=0.043; MF, P=0.004) and high-molecular risk mutations (ET, P=0.024; PV, P=0.023; MF, P=0.001) were found in fewer young respondents. Conclusion: Compared with middle-aged and elderly patients, young patients with MPN had unique clinical and genetic characteristics.

Pathological response and prognostic factors of neoadjuvant PD-1 blockade combined with chemotherapy in resectable esophageal squamous cell carcinoma

PURPOSE

We aimed to investigate the pathological changes, clinicopathological correlation and prognostic factors of neoadjuvant programmed cell death 1 (PD-1) blockade camrelizumab combined with carboplatin and nab-paclitaxel (CCNP) which we have proved its effectiveness in previous research for resectable esophageal squamous cell carcinoma (ESCC).

METHODS

108 patients of resectable ESCC, with a mean follow-up of 13 m (ranging 1-30 m), treated with neoadjuvant CCNP from March 2020 to October 2022 in the First Affiliated Hospital of Sun Yat-sen University were enrolled.

RESULTS

One year overall survival (OS) and disease-free survival (DFS) were 96.4% and 84.7% respectively. Pathological complete response or major pathological response (pCR/MPR) of the primary tumour (T-pCR/T-MPR) and the metastatic lymph node (N-pCR/N-MPR) were 58.3% and 47.5%. Pathological response of both primary tumours (PT) and lymph nodes (LN) metastasis correlated with DFS. LN pathological response was consistent with PT in 70.0% and inconsistent in 30.0% metastatic cases. Higher ratio of CD8+ to FoxP3+ tumour-infiltrating lymphocytes (TILs), earlier ypT stage and PT invasion not beyond circular muscle correlated with better pathological response. Four types of regression patterns of PT and two types of metastatic LN regression were found. A total of 18 (16.7%) out of 108 developed recurrence with a mean time of 6.9 ± 5.3 months. PT pathological response plus ypN and PT invasion beyond circular muscle or not were independent prognostic factors of DFS.

CONCLUSIONS

This study suggested that camrelizumab plus chemotherapy had a high rate of T-pCR/T-MPR for resectable ESCC. T-pCR/T-MPR plus ypN0 and tumour invasion not beyond circular muscle predicted better DFS.

Assessment of a compounded synthetic adrenocorticotropic hormone product in 17 healthy dogs

OBJECTIVES

Synthetic adrenocorticotropic hormone or tetracosactide is routinely used in the diagnosis of hypoadrenocorticism and frequently in the diagnosis and treatment of hyperadrenocorticism. There have been repeated shortages of tetracosactide in recent years in Australia. This study investigated the agreement of serum cortisol after a compounded tetracosactide (Bova Aus), compared to commercial tetracosactide (Synacthen®) in healthy dogs.

METHODS

Prospective crossover study using 20 dogs. Ten dogs received 5 μg/kg Synacthen® on day 1 and 5 μg/kg compounded tetracosactide on Day 2. The other 10 dogs received the reverse order. Cortisol concentrations in each dog 1 h after injection were compared for agreement, which was defined as the limits of agreement of the Bland-Altman ratio to be within a range of 0.8-1.25. Passing-Bablok regression analysis examined for constant and proportional biases.

RESULTS

Three dogs were excluded with post-stimulation serum cortisol concentrations markedly outside reference interval. For the remaining 17 dogs, Bland-Altman ratio analysis of cortisol concentration (tetracosactide/Synacthen®) at 1 h found virtually no constant bias (mean of ratios 1.01;95% CI 0.97-1.05) and 95% limits of agreement were 0.88 (95% CI 0.78-0.90) and 1.17 (95% CI 1.13-1.25). This met our criteria for agreement between cortisol concentrations. Bias of the Bland-Altman difference was 2.8 nmol/L (95% CI -7.2 to 12.8); 95% limits of agreement -35.2 nmol/L (95% CI -57.0 to -26.1) and 40.8 nmol/L (95% CI 31.7-62.6). Passing-Bablok regression analysis did not identify bias.

CONCLUSION

In healthy dogs, cortisol concentrations were in agreement after compounded tetracosactide compared to commercial tetracosactide, Synacthen®.

Circ_0003489 facilitates multiple myeloma progression by targeting miR-433-3p/PBX3 axis

BACKGROUND

Multiple myeloma (MM) is a relatively common hematologic tumor, and the study of non-coding RNAs in MM is gradually increasing. Our study aimed to reveal the regulatory mechanism of circular RNA_0003489 (circ_0003489)/microRNA-433-3p (miR-433-3p)/Pre-B-cell leukemia homeobox 3 (PBX3) axis in MM.

METHODS

Circ_0003489, miR-433-3p and PBX3 contents were measured by real-time quantitative PCR or western blot. Functionally, MM cell proliferation and apoptosis were evaluated using cell counting kit-8, flow cytometry and EdU assays. Interaction between miR-433-3p and circ_0003489 or PBX3 was confirmed with the application of dual-luciferase reporter assay and RNA pull down assay.

RESULTS

Circ_0003489 and PBX3 were upregulated, while miR-433-3p was downregulated in MM tissues. Circ_0003489 knockdown or miR-433-3p overexpression remarkably suppressed MM proliferation and increased apoptosis in vitro. In terms of mechanism, circ_0003489 could sponge miR-433-3p to regulate PBX3. Besides, miR-433-3p downregulation or PBX3 overexpression reversed the inhibition effect of circ_0003489 knockdown on MM progression.

CONCLUSION

Circ_0003489 facilitated MM progression by targeting miR-433-3p/PBX3 axis, suggesting that it might be a potential target for MM.

Reperfusion strategy and late clinical outcomes of patients with ST-elevation myocardial infarction (STEMI) in the absence of standard modifiable risk factors (SMuRFs)

Introduction

There is growing evidence that patients presenting with STEMI in the absence of standard modifiable cardiovascular risk factors (SMuRFs; smoking, hypertension, hypercholesterolemia, diabetes) have poorer outcomes compared to those with atleast one SMuRF. It has been hypothesised that this may be in part due to decreased administration of pharmacotherapies in the post-infarct period due to perceived low risk. Long term outcomes of patients without SMuRFs based on reperfusion strategy received during the index admission have not been investigated.

Purpose

We sought to analyse late clinical outcomes of STEMI patients with and without SMuRFs based on reperfusion strategy received during the index admission.

Methods

All patients who underwent PCI between 2003 and 2014 were identified from a PCI centre STEMI database. Late clinical outcomes of patients with and without SMuRFs were analysed overall and based on reperfusion strategy [primary PCI (pPCI) vs pharmaco-invasive PCI (PI-PCI)]. Propensity matching was used to account for differences in baseline characteristics between the groups.

Results

Amongst 2,091 STEMI patients, 531 (25%) had no SMuRFs (51% pPCI, 49% PI-PCI) and 1560 (75%) had ≥1 SMuRF (52% pPCI, 48% PI-PCI). Unadjusted late mortality in SMuRF-less patients was 13.4% (18.8% pPCI, 7.7% PI-PCI) and for those with ≥1 SMuRF was 9.7% (11.0% pPCI, 8.4% PI-PCI). After propensity-matching clinical and angiographic characteristics, 5 year mortality rates were significantly higher for patients without SMuRFs compared to those with SMuRFs [HR 1.36, CI: 1.03–1.81, p=0.031]. This difference was attenuated for patients who underwent pPCI [HR 1.72, CI: 1.22–2.43, p=0.002]. Interestingly, this discrepancy was not observed amongst individuals who underwent pharmaco-invasive PCI [HR 1.13, CI: 0.53–1.48, p=0.638], as SMuRF-less patients had similar mortality rates to their counterparts. Long term rates of reinfarction, stent thrombosis and target vessel revascularisation were similar between the groups. Additionally, there was no significant difference in rates of stroke and major bleeding amongst all 4 subgroups.

Conclusion

Patients presenting with STEMI in the absence of SMuRFs have increased overall late mortality compared to those with at least one SMuRF. However, this difference was not observed in patients who underwent a pharmaco-invasive strategy, whereby patients without SMuRFs had similar outcomes to those with SMuRFs after adjusting for confounders. Our findings suggest the use of a pharmaco-invasive strategy in appropriate SMuRF-less patients presenting with STEMI.

Funding Acknowledgement

Type of funding sources: None.

Low-density lipoprotein cholesterol levels and long-term bleeding in patients undergoing percutaneous coronary intervention: 5-year outcomes from a large cohort study

Aims

Recent research reported that lower low-density lipoprotein cholesterol (LDL-C) is associated with more in-hospital bleeding in acute coronary syndrome (ACS) patients. However, the association between lower LDL-C levels and long-term bleeding in percutaneous coronary intervention (PCI) patients remains unclear.

Methods

A total of 10724 patients treated with PCI enrolled in ourhospital from January 2013 to December 2013. The primary endpoint was the Bleeding Academic Research Consortium (BARC) type 2, 3 or 5 bleeding at 5 years. The secondary endpoint was intracranial hemorrhage. Taking the LDL-C value of 1.8 mmol/L (70 mg/dL) or 1.4 mmol/L (55 mg/dL) as cut-off points, patients were grouped to analyse, respectively.

Results

Among 9697 PCI patients treated with dual antiplatelet therapy finally enrolled, a total of 411 BARC type 2, 3 or 5 bleedings and 42 intracranial hemorrhage were recorded during a follow-up of 5 years. With LDL-C value of 1.8 mmol/L as cut-off point, multivariate Cox regression showed that lower LDL-C level was not associated with the risk for bleeding [hazard ratio (HR): 1.166, 95% confidence interval (CI): 0.879–1.549]. The result was consistent (HR: 1.185; 95% CI: 0.713–1.968) in a 1:4 propensity-score matching cohort (n=1285). For further study, we performed subgroup analysis which showed that lower LDL-C was not associated with the risk for bleeding in ACS (HR: 1.140; 95% CI: 0.846–1.535) or non-ACS patients (HR: 1.284; 95% CI: 0.909–1.813). With LDL-C value of 1.4 mmol/L as cut-off point, Cox regression showed that lower LDL-C level was not associated with the risk for bleeding in total population, ACS or non-ACS patients (P&gt;0.05). The result was consistent in a 1:4 propensity-score matching cohort (n=760) (P&gt;0.05). As for secondary endpoint, lower LDL-C level was not associated with the risk for intracranial hemorrhage whether the LDL-C value is 1.8 or 1.4 mmol/L as the cut-off point (P&gt;0.05).

Conclusions

To the best of our knowledge, we firstly report lower LDL-C level (whether the LDL-C value is 1.8 or 1.4 mmol/L as the cut-off point) was not the independent risk factor of long-term bleeding in PCI population and ACS or non-ACS subgroup populations.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): CAMS Innovation Fund for Medical Sciences (CIFMS); Young and middle-aged talents in the XPCC Science and Technology Project

Atomistic deformation mechanism of silicon under laser-driven shock compression

Silicon (Si) is one of the most abundant elements on Earth, and it is the most widely used semiconductor. Despite extensive study, some properties of Si, such as its behaviour under dynamic compression, remain elusive. A detailed understanding of Si deformation is crucial for various fields, ranging from planetary science to materials design. Simulations suggest that in Si the shear stress generated during shock compression is released via a high-pressure phase transition, challenging the classical picture of relaxation via defect-mediated plasticity. However, direct evidence supporting either deformation mechanism remains elusive. Here, we use sub-picosecond, highly-monochromatic x-ray diffraction to study (100)-oriented single-crystal Si under laser-driven shock compression. We provide the first unambiguous, time-resolved picture of Si deformation at ultra-high strain rates, demonstrating the predicted shear release via phase transition. Our results resolve the longstanding controversy on silicon deformation and provide direct proof of strain rate-dependent deformation mechanisms in a non-metallic system.

Understanding the how silicon deforms under pressure is important for several fields, including planetary science and materials design. Laser-driven shock compression experiments now confirm that shear stress generated during compression is released via a high-pressure phase transition.

O-235 ACLY entry into the nucleus to bind with EP300 and regulate the genomic DNA and ribosomal DNA transcription during early embryonic development

Study question

ATP citrate lyase (ACLY) is one of the key enzymes to produce acetyl coenzyme A. What is its role in early embryonic development?

Summary answer

ACLY affected by activation of T447, S451 and S455 sites into nucleus and band with EP300 to affect genomic DNA and ribosomal DNA transcription.

What is known already

ACLY is one of the key enzymes to produce acetyl coenzyme A, which participates in fatty acid metabolism and regulates acetylation. Studies have found that ACLY knockout cells can survive, while the cell proliferation capacity will be weakened. ACLY is highly expressed in the cytoplasm of Hela cells colon cancer cells and other somatic cells. When AKT phosphorylates S455 site, ACLY enters the nucleus and participates in DNA damage repair. Its localization and role in embryos have not been studied. The only thing we know is homozygous mice could not be detected at E8.5 days after implantation.

Study design, size, duration

Twenty-four human day 6 developmentally arrested embryos were used to detect ACLY localization. Dozens of ACLY heterozygous female mice were used to test the time points of ACLY homozygous lethality after mating with heterozygous male mice. After zygotes were taken from wild-type C57BL6 mice, microinjection technology was used to explore the effects of knocking down ACLY, changing ACLY location or mutating ACLY. HeLa cells were used to explore at the molecular level.

Participants/materials, setting, methods

In this experiment, we used human abandoned or donated embryos, gene knockout mice, wild-type C57BL6 mice and Hela cell.

The experimental techniques used include in vitro embryo culture, EU staining, plasmid transfection, immunoprecipitation, western blot analysis, in vitro transcription, microinjection, immunofluorescence, RT-PCR and RNA-seq.

Main results and the role of chance

Firstly, our study found its special nuclear localization in early embryos for the first time and proved that its localization was related to embryonic development potential.

Secondly, the specific period of ACLY homozygous death was identified by ACLY heterozygous mice. And by knocking down ACLY or adding inhibitor SB204990, It was found that ACLY played an important role in cell proliferation, blastocyst formation and lineage differentiation of early embryo development.

Thirdly, we proved that ACLY nucleation played an important role in the development of early embryos. and the activated form of T447, S451 and S455 three sites led to ACLY nucleation.

Finally, we found that ACLY affected the level of histone acetylation and UBF acetylation. And then genomic DNA and ribosomal DNA transcription level were decreased. We further explored how the acetyl group produced by ACLY regulated transcription. The interaction between ACLY and EP300 was confirmed by immunofluorescence and COIP experiments. After knocking down EP300 in embryos or inhibiting its function with inhibitor c646, the results are consistent with knocking down ACLY. The above experimental data prove that ACLY affects histone acetylation level and regulates gene opening through the interaction with EP300.

Limitations, reasons for caution

We need to further explore the factors that promote ACLY into the nucleus, so as to add it to in vitro culture to enhance the embryonic development potential.

Wider implications of the findings

The study provides a new mechanism for insulin or lysophosphatidic acid to promote embryo development, and helps to improve the quality of embryo development in the process of embryo culture in vitro.

Trial registration number

not applicable

[Gene expression signature analysis of peripheral blood mononuclear cells from patients with for high altitude pulmonary hypertension and value for potential drug selection]

Objective: To investigate the gene expression characteristics of peripheral blood mononuclear cells from patients with high altitude pulmonary hypertension (HAPH) in Naxi residents living in Lijiang, Yunnan, and to explore the underlying pathogenesis and value for potential drug selection. Methods: This is a case-control study. Six patients with HPAH (HPAH group) and 4 normal subjects (control group) were selected from the Naxi residents who originally lived in Lijiang, Yunnan Province. The general clinical data of the two groups were collected, and the related indexes of pulmonary artery pressure were collected. Peripheral blood mononuclear cells of the subjects were collected for RNA sequencing. The differences on gene expression, regulatory network of transcription factors and drug similarity between the two groups were compared. The results were compared with the public data of idiopathic pulmonary arterial hypertension (IPAH). Biological processes and signal pathways were analyzed and compared between HPAH and IPAH patients. Results: The age of 6 patients with HAPH was (68.1±8.3) years old, and there were 2 males (2/6). The age of 4 subjects in the control group was (62.3±10.9) years old, and there were 2 males (2/4). Tricuspid regurgitation velocity, tricuspid pressure gradient and pulmonary systolic pressure in HAPH group were significantly higher than those in control group (all P<0.05). The results of RNA sequencing showed that compared with the control group, 174 genes were significantly upregulated and 169 genes were downregulated in peripheral blood mononuclear cells of HAPH group. These differentially expressed genes were associated with 220 biological processes, 52 molecular functions and 23 cell components. A total of 21 biological processes and 2 signal pathways differed between HPAH and IPAH groups, most of which were related to inflammation and immune response. ZNF384, SP1 and STAT3 were selected as highly correlated transcription factors by transcription factor prediction analysis. Trichostatin A and vorinostat were screened out as potential drugs for the treatment of HAPH by drug similarity analysis. Conclusions: There are significant differences in gene expression in peripheral blood monocytes between HAPH patients and normal population, and inflammation and immune dysfunction are the main pathogenic factors. Trichostatin A and Vorinostat are potential drugs for the treatment of HAPH.

The role of 18F-FDG PET/CT in predicting the pathological response to neoadjuvant PD-1 blockade in combination with chemotherapy for resectable esophageal squamous cell carcinoma

PURPOSE

Accurate assessment of residual disease of tumor and lymph nodes after neoadjuvant immunochemotherapy is crucial in the active surveillance for patients with pathological complete response (pCR) and the optimal extent of lymphadenectomy for patients with non-pCR. This post hoc analysis aimed to evaluate the performance of ¹⁸F-FDG PET/CT to predict the pathological response to neoadjuvant immunochemotherapy for esophageal squamous cell carcinoma (ESCC).

METHODS

Fifty-eight resectable ESCC patients received two cycles of camrelizumab in combination with chemotherapy and were enrolled in the final analysis. The ¹⁸F-FDG PET/CT scans were acquired at baseline (scan-1) and after immunochemotherapy but prior to surgery (scan-2). Maximum standardized uptake value (SUV_max), mean standardized uptake value (SUV_mean), tumor-to-blood pool SUV_max ratio (SUV_TBR), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were evaluated for their association with the pathological response to immunochemotherapy.

RESULTS

Nineteen patients (32.8%, 19/58) had pCR and thirty-nine patients (67.2%, 39/58) had non-pCR after two doses of camrelizumab and chemotherapy. At scan-2, the SUV_max, SUV_mean, SUV_TBR, TLG, and MTV were significantly lower in pCR than in non-pCR patients. Decrease in TLG and MTV between scan-2 and scan-1 of the same patient was significantly higher in the pCR than in the non-pCR group. In the receiver operating characteristic curve analysis, SUV_max, SUV_mean, SUV_TBR, TLG, and MTV in scan-2 showed excellent predictive value for the pCR of primary tumors. Furthermore, SUV_max in scan-2 were higher in positive lymph nodes than in negative ones, suggesting a high negative predictive ability (98.6%) with a cut-off value at 1.4.

CONCLUSION

The parameters of ¹⁸F-FDG PET/CT have the excellent performance for predicting pCR after the combined neoadjuvant immunochemotherapy in resectable ESCC.

TRIAL REGISTRATION

ChiCTR2000028900. Registered on January 6, 2020.

POS0397 SSD6453, A NOVEL AND HIGHLY SELECTIVE BTK/JAK3 DUAL INHIBITOR IS EFFICACIOUS IN MULTIPLE PRE-CLINICAL MODELS OF INFLAMMATION

Background

The mechanism of inflammatory diseases is complicated and dysfunction of multiple immune cells is thought to be directly related to the pathogenesis. Targeting either JAK-STAT or BCR signaling has been proved solid clinical efficacy in multiple inflammatory diseases, such as rheumatoid arthritis (RA) and multiple sclerosis (MS). And the combination of BTK and JAK inhibitors demonstrated synergistic effects for the treatment of inflammation models in pre-clinic. JAK3 expression is largely restricted to leukocytes and involves functions in JAK1/JAK3 heterodimer in signal transduction, it might be a more effective and safer target. Meanwhile, both BTK and JAK3 possess a cysteine residue in their active site and this feature makes it possible to design a dual inhibitor. SSD6453 is a highly selective and irreversible JAK3/BTK dual inhibitor which may have synergistic effects for the treatment of RA and other inflammatory diseases such as MS.

Objectives

To develop a potent, oral, highly selective JAK3/BTK inhibitor for treatment of multiple inflammatory diseases.

Methods

ADP-GLO based biochemical assays were performed to determine the enzymatic inhibitory effect and selectivity for JAK family. The target engagement was evaluated by IgM induced pBTK and IL-2 induced pSTAT5 in human PBMCs. In vivo efficacy was evaluated by rat collagen-induced arthritic (CIA) model and mice experimental autoimmune encephalomyelitis (EAE) models induced by MOG1-125 or MOG35-55, respectively. BTK occupancy in spleens post last dose 24h and IL-2 induced pSTAT5 in whole blood post last dose 0.5h were used to evaluate targets inhibitions. Osteoclast was stained by IHC in pathological section of rat paws.

Results

In biochemical assays, SSD6453 inhibited BTK and JAK3 with the IC50 values of 3.4 nM and 1.1 nM, respectively. Notably, SSD6453 displayed high selectivity against JAK1 (510 fold), JAK2 (75 fold) and TYK2 (525 fold). In cellular assays, SSD6453 inhibited anti-IgM induced pBTK and IL-2 induced pSTAT5 in human PBMCs with the IC50 values of 18.8 nM and 168.8 nM, respectively. SSD6453 demonstrated favorable PK properties in broad pre-clinical species. Single oral administration of SSD6453 in rat or mouse, resulted in dose-dependent inhibition of BTK and JAKs concurrently. In the rat CIA model in which disease development was accompanied by a robust T-cell and B-cell inflammation response to collagen, SSD6453 dose-dependently inhibited paw edema. And SSD6453 at 10mpk achieved complete (95%) BTK occupancy and JAK3 inhibition and superior efficacy in comparison of tofacitinib (JAK@10 mpk) or evobrutinib (BTK @30mpk) alone, suggesting that concurrent inhibition of JAK3 and BTK lead to synergistic anti-inflammation effects. In addition, ED-1+ osteoclast count decrease was observed in paws, suggesting the prevention of SSD6453 in joint destruction. In two EAE models either induced by MOG1-125 or MOG35-55, which represented T or B dominant inflammation model, respectively, SSD6453 robustly ameliorated disease in both two models. In comparison, BTK inhibitor is efficacious only in the MOG1-125 induced model.

Conclusion

SSD6453 is a novel and high selective BTK/JAK3 dual inhibitor, and demonstrated synergistic efficacy in multiple pre-clinic inflammation models. SSD6453 showed good pharmacokinetic characteristics and well-tolerant in multiple pre-clinical species, and is moving to IND in 2022.

Disclosure of Interests

Feng Zhou Shareholder of: I own the shares of Simcere, Grant/research support from: The work is financially support by Simcere, Employee of: Simcere, Lei Jiang Shareholder of: I own the shares of Simcere, Grant/research support from: The work is financially supported by Simcere, Employee of: I am employee of Simcere, Yuxi Yan Grant/research support from: The work is financially supported by Simcere, Employee of: I am employee of Simcere, Wenqing Yang Shareholder of: I own the shares of Simcere, Grant/research support from: the work is financially supported by Simcere, Employee of: I am employee of Simcere, Feng Tang Shareholder of: I own the shares of Simcere, Grant/research support from: The work is financially supported by Simcere, Employee of: I am employee of simcere, Ping Chen Shareholder of: I own the shares of Simcere, Grant/research support from: The work is financially supported by Simcere, Employee of: I am employee of Simcere, Renhong Tang Shareholder of: I own the shares of Simcere, Grant/research support from: The work is financially supported by Simcere, Employee of: I am employee of Simcere.

Characterization of Restenosis following Carotid Endarterectomy Using Contrast-Enhanced Vessel Wall MR Imaging

BACKGROUND AND PURPOSE

Restenosis is an important determinant of the long-term efficacy of carotid endarterectomy. Our aim was to assess the role of high-resolution vessel wall MR imaging for characterizing restenosis after carotid endarterectomy.

MATERIALS AND METHODS

Patients who underwent vessel wall MR imaging after carotid endarterectomy were included in this study. Restenotic lesions were classified as myointimal hyperplasia or recurrent atherosclerotic plaques based on MR imaging features of lesion compositions. Imaging characteristics of myointimal hyperplasia were compared with those of normal post-carotid endarterectomy and recurrent plaque groups. Recurrent plaques were matched with primary plaques by categories of stenosis, and differences in plaque features were compared between the 2 groups.

RESULTS

Twenty-two recurrent lesions from 18 patients (14 unilateral and 4 bilateral) were classified as myointimal hyperplasia or recurrent plaque. Myointimal hyperplasia showed no difference in enhancement compared with normal post-carotid endarterectomy vessels (5 unilateral) but showed stronger enhancement than recurrent plaques (80.10% [SD, 42.42%] versus 56.74% [SD, 46.54%], P = .042). A multivariate logistic regression model of plaque-feature detection in recurrent plaques compared with primary plaques adjusted for maximum wall thickness revealed that recurrent plaques were longer (OR, 4.27; 95% CI, 1.32-13.85; P = .015) and more likely to involve a flow divider and side walls (OR, 6.96; 95% CI, 1.37-35.28; P = .019). Recurrent plaques had a higher prevalence of intraplaque hemorrhage (61.5% versus 30.8%, P = .048) by a χ² test, but compositional differences were not significant in the multivariate model.

CONCLUSIONS

Vessel wall MR imaging can distinguish recurrent plaques from myointimal hyperplasia and reveal features that may differ between primary and recurrent plaques, highlighting its value for evaluating patients with carotid restenosis.