Stroke while squeezing a pimple: traumatic rupture of a vulnerable carotid artery plaque

Symptomatic non-stenotic carotid disease: current challenges and opportunities for diagnosis and treatment

Symptomatic non-stenotic carotid plaques (SyNC) are an under-researched and under-recognized source of stroke. Various imaging markers of non-stenotic carotid plaques that are associated with stroke risk have been identified, but these causal relationships need to be confirmed in additional prospective studies. Currently, there exists neither a standardized SyNC definition nor a dedicated set of imaging protocols, although researchers have started to address these shortcomings. Moreover, many neuroradiologists are still unaware of the condition, and hence do not comment on high-risk plaque features other than stenosis in their reports. Regarding SyNC treatment, scant data exist as to whether and to what extent medical, interventional and surgical treatments could influence the course of the disease; the relative lack of data on the 'natural' history of untreated SyNC makes treatment comparisons difficult. In our opinion, endovascular SyNC treatment represents the most promising treatment option for SyNC, since it allows for targeted elimination of the embolic source, with few systemic side effects and without the need for general anesthesia. However, currently available carotid devices are designed to treat stenotic lesions, and thus are not optimally designed for SyNC. Developing a device specifically tailored to SyNC could be an important step towards establishing endovascular SyNC treatment in clinical practice. In this review, we provide an overview of the current state of evidence with regard to epidemiological, clinical and imaging features of SyNC, propose a SyNC definition based on imaging and clinical features, and outline a possible pathway towards evidence-based SyNC therapies, with a special focus on endovascular SyNC treatment.

Systemic immune-inflammation index is associated with ulcerative plaque in patients with acute ischemic stroke: A single center exploratory study

PURPOSE

This study explored the correlation between inflammatory markers and ulcerative plaques based on carotid doppler ultrasound (CDU) in individuals with acute ischemic stroke (AIS).

METHODS

A total of 202 cases diagnosed with AIS associated with atherosclerotic plaque (AP) in the carotid artery were enrolled in this research. Collecting clinical baseline data, laboratory data (such as the complete blood count) and imaging data (CDU and Brain magnetic resonance imaging [MRI]). Then the correlation between Systemic immune-inflammation index (SII, SII = P N/L, where P, N, and L were the peripheral blood platelet, neutrophil and lymphocyte counts, respectively), the shape and position of AP, the degree of carotid artery stenosis, and the presence of ulcerative plaques. Cutoff values were determined accordingly.

RESULTS

SII and high sensitivity CRP (hs-CRP) were independent risk factors for the presence of vulnerable carotid plaques. SII, type A plaque, plaque above carotid bifurcation, and severe carotid stenosis were independent risk factors for the presence of ulcerative plaque. The AUC value, the sensitivity, specificity, the best cutoff value of SII in predicting the presence of ulcerative plaque was 0.895, 93.3%, 89.2%, and 537.4 (109 /L), respectively.

CONCLUSION

SII at admission was found to be independently associated with the presence of AIS with vulnerable plaque, especially ulcerative plaques. Moreover, plaque ulceration was more likely to form when the area of higher plaque thickness was located in the upstream arterial wall of maximum plaque thickness (WTmax), plaque was above the carotid bifurcation and severe carotid stenosis.

Non-traditional lipid parameters as potential predictors of carotid plaque vulnerability and stenosis in patients with acute ischemic stroke

OBJECTIVE

Lipid abnormalities are important risk factors in patients with large atherosclerotic strokes. Recent studies have shown that non-traditional lipid parameters are crucial to the development of atherosclerosis and are closely related to the clinical outcome of acute ischemic stroke (AIS). Therefore, we aimed to investigate the relationship between non-traditional lipid parameters and carotid plaque stability and stenosis degree in patients with large atherosclerotic stroke.

METHODS

We retrospectively analyzed 336 patients with AIS. All patients were divided into the non-plaque group, stable plaque group, and vulnerable plaque group according to ultrasound examination. At the same time, the patients were divided into non-stenosis, mild stenosis, moderate stenosis, and severe stenosis groups according to the degree of stenosis. Non-traditional lipid parameters, including residual lipoprotein cholesterol (RLP-C), non-high-density lipoprotein cholesterol (non-HDL-C), non-HDL-C to high-density lipoprotein cholesterol ratio (non-HDL-C/HDL-C), triglyceride to HDL-C ratio (TG/HDL-C), Castelli's risk index (CRI), and the atherogenic index of plasma (AIP). Receiver operating characteristic (ROC) curves and multivariate logistic regression analyses were used to investigate the associations between the non-traditional lipid parameters and carotid plaque vulnerability. Spearman linear correlation analysis was used to test the correlation between variables and the degree of carotid plaque stenosis.

RESULTS

This study population included 336 patients with AIS, of whom 294 had a carotid plaque. Multivariate logistic regression model showed that RLP-C (OR, 3.361; 95%CI, 1.311-8.617), non-HDL-C/HDL-C (OR, 1.699; 95%CI, 1.279-2.258), non-HDL-C (OR, 1.704; 95%CI, 1.143-2.540), CRI-I (OR, 1.573; 95%CI, 1.196-2.068), and CRI-II (OR, 2.022; 95%CI, 1.369-2.985) were independent risk factors for carotid plaque vulnerability. In addition, Spearman correlation analysis showed that the values of RLP-C, non-HDL-C/HDL-C, non-HDL-C, TG/HDL-C, CRI-I, CRI-II, and AIP on admission were positively correlated with the degree of carotid plaque stenosis (all P < 0.001).

CONCLUSION

This study provides evidence that non-traditional lipid parameters (LP-C, non-HDL-C/HDL-C, non-HDL-C, CRI-I, and CRI-II) were potential predictors of carotid plaque vulnerability in patients with AIS. However, no significant correlation was observed between TG/HDL-C and AIP. RLP-C, non-HDL-C/HDL-C, non-HDL-C, TG/HDL-C, CRI-I, CRI-II, and AIP were closely related to the degree of carotid plaque stenosis. Non-traditional lipid parameters can be used as novel biomarkers of carotid plaque vulnerability and stenosis.

Relationship of the Low-Density Lipoprotein Cholesterol/High-Density Lipoprotein Cholesterol Ratio with a Vulnerable Plaque in Patients with Severe Carotid Artery Stenosis: A Case-Control Study in the Han Chinese Population

BACKGROUND

Carotid plaque is often an important factor in ischemic stroke after it changes from stable to vulnerable, and low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) are associated with plaque vulnerability. We aimed to investigate whether the LDL-c/HDL-c ratio, an easily available and novel biomarker, is associated with vulnerable plaques and enhances the warning effect on vulnerability compared to LDL-c or HDL-c alone.

METHODS

We conducted a retrospective study of 187 patients with severe CAS admitted to the Department of Vascular Surgery at the Nanjing Drum Tower Hospital from January 2019 to July 2021. They were divided into a stable plaque group and a vulnerable plaque group according to carotid ultrasonography, carotid angiography (CTA), and plaque pathology. Baseline information was collected and compared between the two groups. Correlation analysis was used to determine the degree of correlation between clinical variables. Univariate and multifactor logistic regression analyses were used to examine independent risk factors for vulnerable plaque in patients with severe CAS. Receiver operating characteristic (ROC) curves were used to assess the capacity of LDL-c/HDL-c to predict the occurrence of vulnerable plaque.

RESULTS

The age of the vulnerable plaque group was 68.12 ± 8.90 years, with 85 males (89.91%); the age of the stable plaque group was 68.77 ± 8.43 years, with 70 males (89.74%). Multivariate logistic regression analysis showed that LDL-c/HDL-c, smoking and diabetes were independent risk factors for vulnerable plaque (all P <0.05). The risk of vulnerable plaque was 4.78-fold greater in the highest LDL-c/HDL-c quartile (≥ 2.63) than in the lowest quartile (≤ 1.31) (P-trend <0.001), and the area under the ROC curve for LDL-c/HDL-c (AUC=0.681, P <0.001) was higher than that for LDL-c and HDL-c.

CONCLUSION

LDL-c/HDL-c, smoking and diabetes were independent risk factors for vulnerable plaque in patients with severe CAS, and LDL-c/HDL-c had a higher predictive value for the presence of vulnerable plaque compared with other lipid parameters.

Relationship of Neutrophil-to-Lymphocyte Ratio with Carotid Plaque Vulnerability and Occurrence of Vulnerable Carotid Plaque in Patients with Acute Ischemic Stroke

Background

Carotid plaque is an undefined risk factor in ischemic stroke and is driven by inflammation. Mounting evidence suggests that neutrophil-to-lymphocyte ratio (NLR) is crucial not only for cerebrovascular events but also in atherosclerosis progression. Here, we aimed to explore the association between the admission NLR and carotid plaque vulnerability as well as the occurrence of vulnerable carotid plaque detected by carotid ultrasonography in patients with acute ischemic stroke (AIS) among Chinese.

Methods

We conducted a retrospective study composed of 588 patients with AIS and 309 healthy controls free of carotid plaque in the Department of Neurology in The Second Hospital of Lanzhou University from March 2014 to February 2015. All patients were classified as nonplaque, stable plaque, and vulnerable plaque groups on the basis of carotid ultrasonography results. The baseline information was collected and compared among the four different groups. The correlation between variables and carotid plaque vulnerability was tested by Spearman linear correlation analysis. To identify the independent predictors for vulnerable carotid plaque, univariate and multivariate logistic regression analysis was performed.

Results

The comparisons of age, sex proportion, history of hypertension, diabetes, and smoking, the levels of HDL-C, Lp(a), BMI, SBP, DBP, Fib, CRP, leukocyte, and NLR among the four groups showed a statistically significant difference (P < 0.05); in particular, the NLR was significantly higher in the vulnerable plaque group as compared to the control (P = 0.043), nonplaque (P = 0.022), and stable plaque groups (P = 0.015). The Spearman correlation analysis presented a positive correlation between carotid plaque vulnerability and age (r = 0.302; P < 0.001), SBP (r = 0.163; P < 0.001), and NLR (r = 0.087; P = 0.034), while the lymphocyte was negatively related to the carotid plaque vulnerability (r = −0.089; P = 0.030). The multivariate logistic regression analysis adjusted for confounding factors revealed that age (odds ratio [OR], 1.042; 95% confidence interval [CI], 1.025-1.060; P < 0.001), male gender (OR, 2.005; 95% CI, 1.394-2.884; P < 0.001), diabetes (OR, 1.481; 95% CI, 1.021-2.149; P = 0.039), SBP (OR, 1.012; 95% CI, 1.003-1.021; P = 0.010), and NLR (OR, 1.098; 95% CI, 1.018-1.184; P = 0.015) are independent predictors of vulnerable carotid plaque in patients with AIS.

Conclusion

The admission NLR is a novel and meaningful biomarker that can be used in predicting carotid plaque vulnerability and the presence of vulnerable carotid plaque assessed by carotid ultrasonography in patients with AIS among Chinese.

Proximity of the Carotid Bifurcation to the Laryngeal Prominence: Results of a Cadaver Study and Recommendations for Safe Pulse Palpation

BACKGROUND/PURPOSE

The carotid bifurcation (CB) is the location of the carotid sinus and the baroreceptors and is also a major site for atherosclerotic plaque formation. Health care providers have therefore been cautioned to avoid the CB during carotid pulse palpation (CPP) to prevent triggering the baroreflex, occluding an artery, or propagating a thrombus. Potential risks of adverse events during CPP may be greater for older adults due to age-related vascular changes and increased risk of baroreceptor hypersensitivity. The exact location of the CB relative to easily identifiable landmarks has, however, not been well-studied. The purpose of this descriptive study was to identify the location of the CB relative to key landmarks in a cadaver sample and to make recommendations allowing clinicians to avoid the CB during CPP.

METHODS

The CB and other regional landmarks in 17 male and 20 female cadavers were exposed by dissection and pins were placed at all landmarks. Digital calipers were then used to measure the distance between the CB and all landmarks.

RESULTS AND DISCUSSION

The mean vertical distance from the laryngeal prominence (LP) to the CB was 25.14 mm for females and 36.13 mm for males. No CBs were located below the LP. Ninety-four percent of female CBs and 100% of male CBs were located above the LP, and 74% of female subjects and 87% of male subjects had CBs greater than 20.00 mm superior to the LP. No clinically relevant relationships were found between the CB and any of the other measured landmarks.

CONCLUSIONS

Based on this cadaver sample, CPP below the level of the LP in a supine individual would be unlikely to compress the CB and thus unlikely to trigger the baroreflex or occlude the region of greatest atherosclerotic buildup. If a pulse is not palpable below the LP, moving vertically up to 1 cm above the LP in a supine individual would be likely to compress the CB in only a small number of cases.

Prevalence of nonstenosing, complicated atherosclerotic plaques in cryptogenic stroke

OBJECTIVES

Our goal was to assess the prevalence of complicated American Heart Association (AHA) lesion type VI plaques in the carotid arteries of patients with cryptogenic stroke.

BACKGROUND

In up to 40% of ischemic stroke patients, no definite cause can be established despite extensive workup (i.e., cryptogenic stroke). To test the hypothesis if nonstenosing complicated carotid plaques may be the underlying etiology in some of these patients, we used high-resolution black-blood carotid magnetic resonance imaging (MRI), which can quantitatively assess plaque composition and morphology with good correlation to histopathology. Specifically, we focused on AHA type VI plaques, which are characterized by hemorrhage, thrombus, or fibrous cap rupture.

METHODS

Thirty-two consecutive patients (22 male; mean age 71.7 ± 11.9 years) with cryptogenic stroke and nonstenosing (<50%) eccentric carotid plaques were recruited from a single stroke unit. All patients underwent extensive clinical workup (brain MRI, duplex sonography, electrocardiography and Holter monitoring, transthoracic and transesophageal echocardiography, and laboratory investigations) to exclude other causes of stroke. All patients received a black-blood carotid MRI at 3-T with fat-saturated pre- and post-contrast T-1-, proton density-, and T-2-weighted and time-of-flight images using surface coils and parallel imaging techniques. Prevalence of AHA type VI plaque was determined in both carotid arteries on the basis of previously published MRI criteria.

RESULTS

AHA type VI plaques were found in 12 of 32 arteries (37.5%) ipsilateral to the stroke, whereas there were no AHA type VI plaques contralateral to the stroke (p = 0.001). The most common diagnostic feature of AHA type VI plaques was intraplaque hemorrhage (75%), followed by fibrous plaque rupture (50%) and luminal thrombus (33%).

CONCLUSIONS

This pilot study suggests that arterio-arterial embolism from complicated, nonstenosing carotid atherosclerotic plaques may play a role in a subgroup of patients previously diagnosed with cryptogenic stroke. To further evaluate the significance of AHA type VI plaques in cryptogenic stroke, future studies will have to analyze both clinical and imaging follow-up data, including event rates for secondary strokes.