MR Imaging of Carotid Artery Atherosclerosis: Updated Evidence on High-Risk Plaque Features and Emerging Trends

MR imaging is well-established as the criterion standard for carotid artery atherosclerosis imaging. The capability of MR imaging to differentiate numerous plaque components has been demonstrated, including those features that are associated with a high risk of sudden changes, thrombosis, or embolization. The field of carotid plaque MR imaging is constantly evolving, with continued insight into the imaging appearance and implications of various vulnerable plaque characteristics. This article will review the most up-to-date knowledge of these high-risk plaque features on MR imaging and will delve into 2 major emerging topics: the role of vulnerable plaques in cryptogenic strokes and the potential use of MR imaging to modify carotid endarterectomy treatment guidelines.

Patients with carotid intraplaque hemorrhage have higher incidence of cerebral microbleeds

Background

Carotid intraplaque hemorrhage (IPH) is considered a strong marker of histologically defined plaque vulnerability leading to cerebrovascular ischemic events. Cerebral microbleeds (CMBs) represent hemorrhage-prone small vessel disease and they are a common finding on brain MRI in patients with cerebrovascular disease. However, the potential mechanism and the risk for CMBs are not clear. The characteristics of carotid lesions have been considered relevant in the relationship between carotid artery atherosclerosis and the presence of CMBs. The potential association between carotid IPH histologically defined and CMBs has not been investigated yet.

Purpose

We have previously reported the prevalence of IPH in patients with non-obstructive carotid disease in patients who underwent carotid endarterectomy (CEA). In this study, we aimed to investigate whether the presence and the extent of carotid IPH are related to the existence of CMBs. We hypothesized that patients with carotid IPH would have a higher risk of CMBs.

Methods

This retrospective study enrolled 101 consecutive patients undergoing CEA with symptomatic (including ischemic stroke, TIA, and amaurosis fugax) or asymptomatic ipsilateral carotid artery disease. Carotid plaque specimens were collected at CEA from all the patients and stained with Movat Pentachrome to identify the presence and the extent (%) of IPH. Neck CTA was obtained to measure the degree of carotid stenosis. Brain MRI was pre-surgically performed and CMBs were studied using T2*-weighted gradient-recalled echo (GRE) or susceptibility-weighted imaging (SWI) sequence. The CMBs were counted and localized. Clinical and biochemical data, comorbidities, and medications were recorded. The association between carotid IPH and CMBs was examined adjusted for other risk factors.

Results

The presence of carotid IPH was in 57 (56.4%) patients. CMBs were more observed in patients with carotid IPH compared to those without IPH [19 (33.3%) vs 5 (11.4%); p=0.010]. Logistic regression analysis demonstrated an association between the extent of IPH in the carotid atheroma and the presence of CMBs [OR 1.051 (95% CI 1.012–1.090); p=0.009]. Moreover, the carotid IPH extent was associated with the number of CMBs (p=0.004). In patients with CMBs, the median degree of ipsilateral carotid stenosis was 40% (35–65%) and it was 70% (50–80%) in those without CMBs, with a significant difference between the two groups (p=0.049).

Conclusions

In patients undergoing CEA, the histologically defined presence of carotid IPH and its extent are associated with CMBs on brain MR imaging. CMBs may be a potential mechanism for cerebrovascular events in patients with carotid atherosclerotic IPH and they may be an imaging marker that can distinguish the severity of the carotid artery disease.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Mayo Clinic Foundation

Reassessing the Carotid Artery Plaque "Rim Sign" on CTA: A New Analysis with Histopathologic Confirmation

BACKGROUND AND PURPOSE

The CTA "rim sign" has been proposed as an imaging marker of intraplaque hemorrhage in carotid plaques. This study sought to investigate such findings using histopathologic confirmation.

MATERIALS AND METHODS

Included patients had CTA neck imaging <1 year before carotid endarterectomy. On imaging, luminal stenosis and the presence of adventitial (<2-mm peripheral) and "bulky" (≥2-mm) calcifications, total plaque thickness, soft-tissue plaque thickness, calcification thickness, and the presence of ulcerations were assessed. The rim sign was defined as the presence of adventitial calcifications with internal soft-tissue plaque of ≥2 mm in maximum thickness. Carotid endarterectomy specimens were assessed for both the presence and the proportional makeup of lipid material, intraplaque hemorrhage, and calcification.

RESULTS

Sixty-seven patients were included. Twenty-three (34.3%) were women; the average age was 70.4 years. Thirty-eight (57.7%) plaques had a rim sign on imaging, with strong interobserver agreement (κ = 0.85). A lipid core was present in 64 (95.5%) plaques (average, 22.2% proportion of plaque composition); intraplaque hemorrhage was present in 52 (77.6%), making up, on average, 13.7% of the plaque composition. The rim sign was not associated with the presence of intraplaque hemorrhage (P = .11); however, it was associated with a greater proportion of intraplaque hemorrhage in a plaque (P = .049). The sensitivity and specificity of the rim sign for intraplaque hemorrhage were 61.5% and 60.0%, respectively.

CONCLUSIONS

The rim sign is not associated with the presence of intraplaque hemorrhage on histology. However, it is associated with a higher proportion of hemorrhage within a plaque and therefore may be a biomarker of more severe intraplaque hemorrhage, if present.

Volatiloma analyses of four South African Helichrysum spp. grown in Italy

The volatiloma of four Helichrysum species (H. anomalum, H reflexum, H. retortum and H. rugulosum) was analysed here for the first time by GC-MS for a chemotaxonomic contribution to this genus. Sesquiterpene hydrocarbons (SHs) prevailed in the aroma profile (VOCs) of H. reflexum, H. rugulosum and H. anomalum (74.7%, 93.6% and 41.6%, respectively), even though the main compounds were different (β-caryophyllene, α-humulene and α-copaene, respectively). The VOCs of H. retortum showed a high percentage of aliphatic hydrocarbons (NTs, 77.7%) mainly represented by octyl ether. The essential oil composition of each of H. rugulosum and H. retortum followed the same trend as VOCs related to the main class (SHs and NTs, respectively). In H. reflexum EO, the SHs were replaced by oxygenated sesquiterpenes (OS, 49.0%) with caryophyllene oxide as the main compound, while in H. anomalum the SHs were swapped in NTs (37.3%).

Higher levels of serum phosphorus are associated with coronary calcification post heart transplantation

Background

A higher serum phosphorus level, although within the normal range has been linked to coronary artery and aortic calcification in the non-transplant population. Coronary calcification is mostly associated with donor-derived lesions, and is uncommon within the first years after heart transplantation.

Purpose

We aimed to investigate the association of phosphorus levels with plaque calcification after heart transplantation.

Methods

A total of 156 patients who underwent virtual histology intravascular ultrasound (VH-IVUS) studies for cardiac allograft vasculopathy (CAV) surveillance and had fasting serum phosphorus levels &lt;4.5 mg/dL, were included in the analyses. IVUS analyses were performed in the proximal left anterior descending artery, and plaque composition of dense calcium (DC) was evaluated using VH-IVUS, and presented as percent DC of total plaque volume. The patients were separated into 3 groups according to tertiles of serum phosphorus levels.

Results

Mean recipient and donor ages were 54±13 and 31±14 years, respectively. Mean serum phosphorus in recipients was 3.5±0.6 mg/dL, with median time after transplantation at the IVUS studies of 6 (3,10) years. There were no significant differences in %DC between phosphorus tertiles in patients who underwent IVUS within 6 years after transplantation (p=0.11, Fig. 1A). However, beyond 6 years after transplantation, we observed an incremental association between phosphorus levels and the extent of calcification (p=0.02, Fig. 1B). In this group, serum phosphorus levels significantly correlated with %DC (standardized β=0.29, P=0.008), and this correlation remained significant after adjustment for donor age, recipient age, and eGFR (standardized β=0.26, P=0.001).

Conclusion

Higher serum phosphorus levels were associated with a level-dependent increase in calcified coronary artery plaque in patients starting 6 years post heart transplant. Long-term exposure to higher serum phosphorus, even within the normal range, might promote plaque calcification after heart transplantation.

Funding Acknowledgement

Type of funding sources: None.

Uterus transplant and controversial assisted reproductive technologies: can the right to parenthood clash with ethical precepts?

Abstract

Fast-developing assisted reproductive techniques based on innova- tive technologies have given rise to incredibly consequential ethical challenges of unprecedented scope. The development of innovative assisted reproductive technologies (ARTs) has steadily risen since the late 1970s. Until just over 20 years ago, those who sought to become parents had no way to overcome their infertility or sterility issues, but can now achieve parenthood and have children with at least a partial genetic and/or biological relationship. Treatments aimed at ovarian stimulation, artificial insemination, either by using the sperm of a husband or of an unrelated donor, in vitro fertilization with embryo transfer, gamete and zygote intrafallopian transfers, and intracyto- plasmic sperm injection are among the options currently available. A major ethical quandary linked to ARTs is the one arising from unused embryos, i.e. supernumerary embryos which were not implanted. Still, aside from ethical concerns stemming from embryo rights, in such a fast-evolving field, a solid ethical foundation is absolutely necessary to provide guidance for regulations and legislation. This is especially true considering how assisted reproductive practices such as surrogacy and uterus transplant (UTx) are even more controversial, hence the need to rely on a broadly acknowledged and shared set of principles for their regulation, by virtue of their unique distinctive traits which challenge our ethical and moral compass at its very core.

Screening of the essential oil effects on human H1N1 influenza virus infection: an in vitro study in MDCK cells

Nineteen essential oils (EOs) obtained from different plants have been evaluated for their potential in vitro anti-H1N1 influenza virus efficacy. Both multivariate analyses and bivariate correlation were performed to better understand how the composition influences the activity. The results evidenced that for the laboratory distilled EOs both rosemary hybrids (S. x lavandulaceus and S. x mendizabalii) showed a good antiviral activity with low cytotoxic effect. Concerning the commercial ones: Eucalyptus globulus and Juniperus communis EOs exhibited virtuous effects on influenza virus. These results were confirmed by the multivariate analyses and only eucalyptol showed a positive correlation with cell viability. On the contrary, o-cymene and terpinolene correlated to the inhibitory effect. Rosemary hybrids, E. globulus and J. communis could be considered as promising candidate to develop new alternative anti-H1N1 natural agent.

Trace elements and the carotid plaque: the GOOD (Mg, Zn, Se), the UGLY (Fe, Cu), and the BAD (P, Ca)?

Multiple epidemiological studies have suggested that industrialization and progressive urbanization should be considered one of the main factors responsible for the rising of atherosclerosis in the developing world. In this scenario, the role of trace metals in the insurgence and progression of atherosclerosis has not been clarified yet. In this paper, the specific role of selected trace elements (magnesium, zinc, selenium, iron, copper, phosphorus, and calcium) is described by focusing on the atherosclerotic prevention and pathogenesis plaque. For each element, the following data are reported: daily intake, serum levels, intra/extracellular distribution, major roles in physiology, main effects of high and low levels, specific roles in atherosclerosis, possible interactions with other trace elements, and possible influences on plaque development. For each trace element, the correlations between its levels and clinical severity and outcome of COVID-19 are discussed. Moreover, the role of matrix metalloproteinases, a family of zinc-dependent endopeptidases, as a new medical therapeutical approach to atherosclerosis is discussed. Data suggest that trace element status may influence both atherosclerosis insurgence and plaque evolution toward a stable or an unstable status. However, significant variability in the action of these traces is evident: some - including magnesium, zinc, and selenium - may have a protective role, whereas others, including iron and copper, probably have a multi-faceted and more complex role in the pathogenesis of the atherosclerotic plaque. Finally, calcium and phosphorus are implicated in the calcification of atherosclerotic plaques and in the progression of the plaque toward rupture and severe clinical complications. In particular, the role of calcium is debated. Focusing on the COVID-19 pandemia, optimized magnesium and zinc levels are indicated as important protective tools against a severe clinical course of the disease, often related to the ability of SARS-CoV-2 to cause a systemic inflammatory response, able to transform a stable plaque into an unstable one, with severe clinical complications.

Helichrysum araxinum Takht. ex Kirp. grown in Italy: volatiloma composition and in vitro antimicrobial activity

In the present work the composition of biogenic volatile organic compounds (BVOCs) and the essential oil (EO) of Helichrysum araxinum Takht. ex Kirp. aerial parts, together with the antimicrobial activity, were investigated. The results showed the prevalence of sesquiterpene hydrocarbons in both spontaneous emissions as well as in the EO. The main compounds of BVOCs were γ-curcumene (10.7%), γ-muurolene (9.2%), and β-selinene (8.5%). This latter constituent also showed a similar amount in the EO and represented the most abundant compounds together with α-selinene (8.0%). It is Interesting to note the same percentage of monoterpene hydrocarbons (MHs) in both the aroma profile and the EO (18.0%) with the same most abundant compounds: β-pinene (6.3% in BVOCs vs. 5.1% in EO, respectively) and limonene (4.5% in VOCs vs. 4.9% in EO, respectively). With regard to the antimycotic activity, the EO showed to be inactive against the tested strains, while a moderate antibacterial activity was shown against Staphylococcus isolates.

Volatiles and Antifungal-Antibacterial-Antiviral Activity of South African Salvia spp. Essential Oils Cultivated in Uniform Conditions

Spontaneous emissions of S. dentata Aiton and S. scabra Thunb., as well as the essential oil (EO) composition of the cited species, together with S. aurea L., were investigated. The chemical profile of the first two species is reported here for the first time. Moreover, in vitro tests were performed to evaluate the antifungal activity of these EOs on Trichophyton mentagrophytes, Microsporum canis, Aspergillus flavus, Aspergillus niger, and Fusarium solani. Secondly, the EO antibacterial activity against Escherichia coli, Staphylococcus aureus, and Staphylococcus pseudointermedius was examined, and their antiviral efficacy against the H1N1 influenza virus was assessed. Leaf volatile organic compounds (VOCs), as well as the EOs obtained from the arial part of Salvia scabra, were characterized by a high percentage of sesquiterpene hydrocarbons (97.8% and 76.6%, respectively), mostly represented by an equal amount of germacrene D (32.8% and 32.7%, respectively). Both leaf and flower spontaneous emissions of S. dentata, as well as the EO composition, showed a prevalence of monoterpenes divided into a more or less equal amount of hydrocarbon and oxygenated compounds. Interestingly, its EO had a non-negligible percentage of oxygenated sesquiterpenes (29.5%). S. aurea EO, on the contrary, was rich in sesquiterpenes, both hydrocarbons and oxygenated compounds (41.5% and 33.5%, respectively). S. dentata EO showed good efficacy (Minimal Inhibitory Concentration (MIC): 0.5%) against M. canis. The tested EOs were not active against E. coli and S. aureus, whereas a low inhibition of S. dentata EO was observed on S. pseudointermedius (MIC = 10%). Once again, S. dentata EO showed a very good H1N1 inhibition; contrariwise, S. aurea EO was completely inactive against this virus. The low quantity of S. scabra EO made it impossible to test its biological activity. S. dentata EO exhibited interesting new perspectives for medicinal and industrial uses.

Perivascular Fat Density and Contrast Plaque Enhancement: Does a Correlation Exist?

BACKGROUND AND PURPOSE

Inflammatory changes in the fat tissue surrounding the coronary arteries have been associated with coronary artery disease and high-risk vulnerable plaques. Our aim was to investigate possible correlations between the presence and degree of perivascular fat density and a marker of vulnerable carotid plaque, namely contrast plaque enhancement on CTA.

MATERIALS AND METHODS

One-hundred patients (76 men, 24 women; mean age, 69 years) who underwent CT angiography for investigation of carotid artery stenosis were retrospectively analyzed. Contrast plaque enhancement and perivascular fat density were measured in 100 carotid arteries, and values were stratified according to symptomatic (ipsilateral-to-cerebrovascular symptoms)/asymptomatic status (carotid artery with the most severe degree of stenosis). Correlation coefficients (Pearson ρ product moment) were calculated between the contrast plaque enhancement and perivascular fat density. The differences among the correlation ρ values were calculated using the Fisher r-to-z transformation. Mann-Whitney analysis was also calculated to test differences between the groups.

RESULTS

There was a statistically significant positive correlation between contrast plaque enhancement and perivascular fat density (ρ value = 0.6582, P value = .001). The correlation was stronger for symptomatic rather than asymptomatic patients (ρ value = 0.7052, P value = .001 versus ρ value = 0.4092, P value = .001).

CONCLUSIONS

There was a positive association between perivascular fat density and contrast plaque enhancement on CTA. This correlation was stronger for symptomatic rather than asymptomatic patients. Our results suggest that perivascular fat density could be used as an indirect marker of plaque instability.

Volatilome Analyses and In Vitro Antimicrobial Activity of the Essential Oils from Five South African Helichrysum Species

Helichrysum genus was used in folk South African medicine to treat various human disorders. As a part of our on-going research addressing the exploitation of South African plants belonging to this genus, five species were investigated for their volatile and antimicrobial activities. The volatile organic compounds (VOCs) and the essential oils (EOs) were analysed by gas chromatography mass spectrometry (GC-MS). Microdilution was the method used for assessing both antimycotic and antibacterial activities, which was also tested by Kirby-Bauer agar disc diffusion. Total monoterpenes (TMs) dominated the VOCs of four species (H. trilineatum (70.6%), H. edwardsii (79.3%), H. cooperi (84.5%), and H. pandurifolium (57.0%)). H. cooperi and H. edwardsii EOs showed the predominance of TMs (68.2% and 84.5%, respectively), while H. pandurifolium and H. trilineatum EOs were characterized by the prevalence of TSs (86.5% and 43.6%, respectively). H. odoratissimum EO evidenced a similar amount of both TMs (49.5%) and TSs (46.4%). Microsporum canis was more sensitive to these EOs. The lowest minimum inhibitory concentration (MIC) was observed with H. pandurifolium and H. edwardsii EOs (0.25%). H. pandurifolium and H. trilineatum had a good effect on Staphylococcus aureus (MIC 5%). These findings open new perspectives for the exploitation of these natural compounds for application in cosmetics and pharmaceutics.

Pain perception in NICU: a pilot questionnaire

PURPOSE

Neonatal pain management has made a great step forward over the last several years. Despite the drafting of International guidelines, an under-treatment of neonatal pain is still reported.

MATERIALS AND METHODS

Medical and paramedical personnel working in five Italian NICUs were asked to complete a questionnaire about pain management. The questionnaire was comprised of three sections: (i) brief explanation of the purpose; (ii) demographic information, including age, profession, religious beliefs, and hospital level; (iii) questionnaire about pain management and prevention.

RESULTS

One-hundred and forty caregivers participated in this study. Non-pharmacological analgesia during heel prick or venipuncture was used by 64% and 60% of them, respectively; topical analgesia was performed in 13% of venipunctures; no analgesia was used in 30% of cases for both heel prick and venipuncture. In the case of lumbar puncture, 35% of participants used topical analgesia, 15% non-pharmacological approach, 10% opioids, and 6% intravenous paracetamol. While 65% of participants gave a score of 4 out of 5 about the importance of pain treatment, 39% of them reported that in their department no pain scales were used.

CONCLUSIONS

Pain treatment in these NICUs is still far to be optimal. This nonetheless reflects a worldwide trend, which requires more attention on pain prevention, assessment, and treatment.

Quantitative monitoring by polymerase colony assay of known mutations resistant to ABL kinase inhibitors

Resistance to molecularly targeted chemotherapy, and the development of novel agents that are active against resistant forms of target proteins create the need for a sensitive and quantitative assay to monitor drug-resistant mutations in patients to guide treatment and assess response. Here, we describe an application of the polymerase colony (polony) method to identify and quantify known point mutations in the BCR-ABL oncogene in patients with chronic myelogenous leukemia who evolve resistance to ABL kinase inhibitors. The assay can detect mutations with a sensitivity of 10(-4), quantify the burden of drug-resistant cells, and simultaneously monitor the dynamics of several coexisting mutations. As a proof of concept, we analysed blood samples from three patients undergoing therapy with ABL kinase inhibitors and found that the patients' response to therapy correlated with our molecular monitoring. We were also able to detect mutations emerging in patients long before clinical relapse. Therefore, the polony assay could be applied to a larger patient sample to assess the utility of early mutation detection in patient-specific treatment decisions. Finally, this methodology could be a valuable research tool to shed light on the natural behavior of mutations pre-existing kinase inhibitors therapy and either disappearing over time or slowly taking over.

A third generation regimen VACOP-B with or without adjuvant radiotherapy for aggressive localized non-Hodgkin's lymphoma: report from the Italian Non-Hodgkin's Lymphoma Co-operative Study Group

The objective of this multicenter prospective study was to determine the clinical efficacy and toxicity of a polychemotherapeutic third generation regimen, VACOP-B, with or without radiotherapy as front-line therapy in aggressive localized non-Hodgkin's lymphoma. Ninety-three adult patients (47 males and 46 females, median age 45 years) with aggressive localized non-Hodgkin's lymphoma, 43 in stage I and 50 in stage II (non-bulky), were included in the study. Stage I patients received VACOP-B for 6 weeks plus involved field radiotherapy and stage II patients received 12 weeks VACOP-B plus involved field radiotherapy on residual masses. Eighty-six (92.5%) achieved complete remission and 4 (4.3%) partial remission. Three patients (3.2%) were primarily resistant. Ten-year probability of survival, progression-free survival and disease-free survival were 87.3, 79.9 and 83.9%, respectively. Eighty-four patients are surviving at a median observation time of 57 months (range: 6-126). Statistical analysis showed no difference between stages I and II in terms of response, ten-year probability of survival, progression-free survival or disease-free survival. Side effects and toxicity were negligible and were similar in the two patient groups. The results of this prospective study suggest that 6 weeks of VACOP-B treatment plus radiotherapy may be the therapy of choice in stage I aggressive non-Hodgkin's lymphoma. Twelve weeks of VACOP-B treatment with or without radiotherapy was shown to be effective and feasible for stage II. These observations need to be confirmed by a phase III study comparing first and third generation protocols in stage I-II aggressive non-Hodgkin's lymphoma.