Complex Plaques Research Articles

Mouse Hepatitis Virus Infection Remodels Connexin43-Mediated Gap Junction Intercellular Communication In Vitro and In Vivo.

Gap junctions (GJs) form intercellular channels which directly connect the cytoplasm between neighboring cells to facilitate the transfer of ions and small molecules. GJs play a major role in the pathogenesis of infection-associated inflammation. Mutations of gap junction proteins, connexins (Cxs), cause dysmyelination and leukoencephalopathy. In multiple sclerosis (MS) patients and its animal model experimental autoimmune encephalitis (EAE), Cx43 was shown to be modulated in the central nervous system (CNS). The mechanism behind Cx43 alteration and its role in MS remains unexplored. Mouse hepatitis virus (MHV) infection-induced demyelination is one of the best-studied experimental animal models for MS. Our studies demonstrated that MHV infection downregulated Cx43 expression at protein and mRNA levels in vitro in primary astrocytes obtained from neonatal mouse brains. After infection, a significant amount of Cx43 was retained in endoplasmic reticulum/endoplasmic reticulum Golgi intermediate complex (ER/ERGIC) and GJ plaque formation was impaired at the cell surface, as evidenced by a reduction of the Triton X-100 insoluble fraction of Cx43. Altered trafficking and impairment of GJ plaque formation may cause the loss of functional channel formation in MHV-infected primary astrocytes, as demonstrated by a reduced number of dye-coupled cells after a scrape-loading Lucifer yellow dye transfer assay. Upon MHV infection, a significant downregulation of Cx43 was observed in the virus-infected mouse brain. This study demonstrates that astrocytic Cx43 expression and function can be modulated due to virus stress and can be an appropriate model to understand the basis of cellular mechanisms involved in the alteration of gap junction intercellular communication (GJIC) in CNS neuroinflammation. We found that MHV infection leads to the downregulation of Cx43 in vivo in the CNS. In addition, results show that MHV infection impairs Cx43 expression in addition to gap junction communication in primary astrocytes. After infection, Cx43 did not traffic normally to the membrane to form gap junction plaques, and that could be the basis of reduced functional gap junction coupling between astrocytes. This is an important first step toward understanding how viruses affect Cx43 expression and trafficking at the cellular level. This may provide a basis for understanding how structural alterations of astrocytic gap junctions can disrupt gap junction communication between other CNS cells in altered CNS environments due to infection and inflammation. More specifically, alteration of Cx43 may be the basis of the destabilization of Cx47 in oligodendrocytes seen in and around inflammatory demyelinating plaques in MS patients.

The diagnostic yield of transesophageal echocardiography in patients with cryptogenic cerebral ischaemia: a meta‐analysis

The diagnostic utility of transesophageal echocardiography (TEE) in patients with cryptogenic ischaemic stroke (IS) or transient ischaemic attack (TIA) remains controversial. A systematic review and meta-analysis was performed according to PRISMA guidelines to estimate the pooled prevalence of potential cardioembolic causes detected by TEE in prospective observational studies of cryptogenic IS/TIA. Cardiac conditions causally associated with cerebral ischaemia were considered to be intramural thrombi and intracardiac tumors according to ASCO phenotyping of IS. Thirty-five eligible studies, comprising 5772 patients (mean age 53.6 years, 56.9% men) were identified. The most common TEE finding was ascending aorta and/or aortic arch atheroma [51.2% (27.4%-74.5%)], followed by patent foramen ovale (PFO) [43.2% (36.3%-50.4%)]. Complex aortic plaques and large PFOs were reported in 14% (10.2%-18.9%) and 19.5% (16.6%-22.8%) of TEE evaluations. The prevalence of atrial septal aneurysm was 12.3% (7.9%-18.7%) and was significantly higher in conjunction with PFO presence (risk ratio 2.04, 95% confidence interval 1.63-2.54, P < 0.001). The prevalence of left atrial thrombus [3.0% (1.1%-8.3%)] and spontaneous echo contrast [3.8% (2.3%-6.2%)] was low. The prevalence of intracardiac tumors was extremely uncommon [0.2% (0%-0.7%)]. Significant heterogeneity was identified (I(2) > 60%) in the majority of analyses. Heterogeneity was not affected by cryptogenic stroke definition (TOAST versus alternative criteria). After dichotomizing available studies using a cut-off of 50 years, PFO was significantly (P = 0.001) more prevalent in younger than in older patients. Routine TEE in patients with cryptogenic IS/TIA commonly identifies abnormal findings. However, the prevalence of cardiac conditions considered to be causally associated with cerebral ischaemia (intracardiac thrombi and tumors) is low.

Coronary atherosclerosis and risk of acute coronary syndromes in chronic kidney disease using angioscopy and the kidney disease: Improving Global Outcomes (KDIGO) classification

ObjectiveThis 8-year follow-up cohort study evaluated and compared the degree of coronary atherosclerosis in chronic kidney disease (CKD) according to the Kidney Disease: Improving Global Outcomes (KDIGO) classification using multivessel angioscopy and investigated the impact of the vulnerability of coronary arteries on the relationship between the classification and risk of acute coronary syndromes (ACS). MethodsWe studied 89 coronary artery disease patients who underwent angioscopic observation of multiple coronary arteries. The patients were divided into 3 groups: Risk 0, 1, and 2 were equivalent to low risk, moderately high risk, and high and severely high risk, respectively. We examined the frequencies of complex and yellow plaques. Furthermore, we followed all patients for de novo ACS, dividing into two groups according to the existence of vulnerable coronary atherosclerosis (VCA) based on angioscopic findings. ResultsThe number of yellow plaques per vessel, maximum yellow grade, number of complex plaques per vessel, and cumulative incidence of ACS in all patients were significantly associated with Risk grade progression (p < 0.05 for trend). Among the patients with VCA, Risk 2 had a higher incidence of ACS than Risk0 (p < 0.014) and Risk 1 (p < 0.007), whereas Risk 0 and Risk 1 had similar outcomes. Among the patients without VCA, no de novo ACS events were seen regardless of the Risk group. ConclusionsCoronary atherosclerosis progressed in the early stages of CKD, and once it reached to a vulnerable stage, advanced CKD patients had a synergistically increased risk of ACS.

Optical coherence tomography for serial in vivo imaging of aortic plaque in the rabbit: a preliminary experience

BackgroundIn this pilot feasibility study, we aimed to establish a reproducible means of performing serial optical coherence tomography (OCT) procedures in the abdominal aorta of the cholesterol-fed rabbit.MethodsEight cholesterol-fed New...

Impact of transesophageal echocardiography on clinical management of patients over age 50 with cryptogenic stroke and normal transthoracic echocardiogram.

The utility of transesophageal echocardiography (TEE) subsequent to a normal transthoracic echocardiogram (TTE) in older patients with an unexplained stroke is uncertain. Two hundred sixty-three consecutive patients over the age of 50 years hospitalized with a clinical stroke confirmed with brain magnetic resonance imaging and a normal TTE were retrospectively analyzed. Patients with atrial fibrillation, atrial flutter, or any other causative reason for stroke were excluded. TEE was analyzed for findings that could explain the etiology of stroke as well as findings that would change therapy based on current guidelines. Baseline characteristics included a mean age of 66.7 years (range, 50-91 years); 42.5% of patients were female. A possible etiology of stroke was discovered by TEE in 111 (42.2%) patients and included 1 or more of the following: complex plaque of the ascending aorta or arch, patent foramen ovale, atrial septal aneurysm, both atrial septal aneurysm and patent foramen ovale, or spontaneous contrast. Only 1 patient (0.4%) had a finding that changed immediate management, which was a thrombus in the left atrial appendage for which anticoagulation was prescribed. Follow-up was available at 6 months on 85 patients, of whom 13 (15%) had been discovered to have developed atrial fibrillation. In our study population, when performed subsequent to a normal TTE in patients aged >50 years with cryptogenic stroke, TEE demonstrated a high diagnostic value, but had minimal incremental effect on patient management.

Concurrent Carotid Inflammation in Acute Coronary Syndrome as Assessed by 18F-FDG PET/CT: A Possible Mechanistic Link for Ischemic Stroke

Patients with acute coronary syndrome (ACS) are prone to ischemic stroke (IS) especially during the early phase. ACS patients are more likely to have concurrent complex carotid plaques which, when destabilized, may serve as a source of distal embolism. This study investigated whether inflammatory activity in carotid artery was increased in ACS survivors compared to chronic stable angina (CSA) patients. We prospectively enrolled 74 patients with ACS or CSA (39 ACS patients versus 35 CSA patients), and fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) was performed within 1 week after diagnosis. Carotid PET signal was quantified as standardized uptake value (SUV) and target-to-background ratio (TBR, carotid SUV/jugular venous SUV). Baseline characteristics were similar between groups. TBRs and SUVs were significantly higher in the carotid arteries of ACS patients than those of CSA patients (P < .001). Systemic inflammatory biomarker correlated significantly with carotid FDG uptake (high-sensitivity C-reactive protein versus average SUV: r = .361, P = .002), and the presence of cardiovascular risk factors was also related to inflammation activity. During follow-up, 3 cerebrovascular events occurred in ACS patients (including 1 early IS in a patient with severe baseline carotid inflammation), whereas none in CSA patients (P = .057). This study provided in vivo evidence that ACS survivors might experience concurrent carotid arterial inflammation. Our findings supported the role of systemic immune activation contributing to multiarterial instability in symptomatic atherosclerosis as a possible mechanistic link between ACS and IS.

Ultrasound Characteristics of Symptomatic Carotid Plaques: A Systematic Review and Meta-Analysis

Background: Ultrasound is the most commonly used imaging modality for assessing carotid artery stenosis. A number of studies have demonstrated that surface irregularities, heterogeneous echotexture and hypoechoic plaques are risk factors for acute ischemic stroke. We performed a systematic review and meta-analysis of the literature to better define the risk of stroke based on the sonographic characteristics of carotid plaques. Materials and Methods: We performed a comprehensive search for studies reporting imaging findings of symptomatic and asymptomatic carotid plaques on ultrasound using MEDLINE and EMBASE. We included both case-control and cohort studies examining the relationship between complex plaque and acute ischemic stroke or transient ischemic attack. Complex plaque was defined as plaque that had any of the following characteristics: heterogeneous echogenicity, echolucency, neovascularization, surface irregularity, ulceration, and intraplaque motion. Meta-analyses using the random-effects model were performed for complex plaque and each of the individual complex plaque characteristics. p < 0.05 was considered statistically significant. We explored the impact of publication bias by constructing funnel plots and testing their symmetry. We conducted the meta-analysis using Comprehensive Meta-analysis version 2.2, Englewood, N.J., USA. Results: A total of 1,013 articles were screened and 23 studies with 6,706 carotid plaques were included. Ultrasound plaque characteristics with a higher prevalence in individuals with symptomatic compared to asymptomatic carotid artery stenosis included plaque neovascularity (OR = 19.68, 95% CI = 3.14-123.16), complex plaque (OR = 5.12, 95% CI = 3.42-7.67), plaque ulceration (OR = 3.58, 95% CI = 1.66-7.71), plaque echolucency (OR = 3.99, 95% CI = 3.06-5.19) and intraplaque motion (OR = 1.57, 95% CI = 1.02-2.41). Variables not associated with symptom status included heterogenous echotexture (OR = 2.68, 95% CI = 0.56-12.80) and surface irregularity without ulceration (OR = 2.38, 95% CI = 0.70-8.11). No evidence of publication bias was observed based on Eggers test (p value of 0.05 for complex plaque and 0.53 for plaque echolucency). The remaining plaque features had insufficient data to assess for publication bias. Conclusions: Our meta-analysis and systematic review of the literature demonstrated that plaques with complex features, particularly those with echolucency, neovascularization, ulceration and intraplaque motion are associated with ischemic symptoms. Assessment of carotid plaque on ultrasound may provide stroke risk information beyond measurement of luminal stenosis. Thus, sonographic evaluation of carotid artery stenosis should focus on the detection of these plaque characteristics in addition to quantifying the degree of stenosis.

Molecular Imaging of Platelet-Endothelial Interactions and Endothelial von Willebrand Factor in Early and Mid-Stage Atherosclerosis.

Nonthrombotic platelet-endothelial interactions may contribute to atherosclerotic plaque development, although in vivo studies examining mechanism without platelet preactivation are lacking. Using in vivo molecular imaging at various stages of atherosclerosis, we quantified platelet-endothelial interactions and evaluated the contribution of major adhesion pathways. Mice deficient for the low-density lipoprotein receptor and Apobec-1 were studied as an age-dependent model of atherosclerosis at 10, 20, 30, and 40 weeks of age, which provided progressive increase in stage from early fatty streak (10 weeks) to large complex plaques without rupture (40 weeks). Platelet-targeted contrast ultrasound molecular imaging of the thoracic aorta performed with microbubbles targeted to GPIbα demonstrated selective signal enhancement as early as 10 weeks of age. This signal increased progressively with age (almost 8-fold increase from 10 to 40 weeks, analysis of variance P<0.001). Specificity for platelet targeting was confirmed by the reduction in platelet-targeted signal commensurate with the decrease in platelet count after immunodepletion with anti-GPIb or anti-CD41 antibody. Inhibition of P-selectin in 20 and 40 weeks atherosclerotic mice resulted in a small (15% to 30%) reduction in platelet signal. Molecular imaging with microbubbles targeted to the A1 domain of von Willebrand factor demonstrated selective signal enhancement at all time points, which did not significantly increase with age. Treatment of 20 and 40 week mice with recombinant ADAMTS13 eliminated platelet and von Willebrand factor molecular imaging signal. Platelet-endothelial interactions occur in early atherosclerosis. These interactions are in part caused by endothelial von Willebrand factor large multimers, which can be reversed with exogenous ADAMTS13.

Aortic arch atherosclerosis in patients with severe aortic stenosis can be argued by greater day-by-day blood pressure variability

Background and PurposeAlthough it is well known that the prevalence of aortic arch plaques, one of the risk factors for ischemic stroke, is high in patients with severe aortic stenosis, the underlying mechanisms are not well understood. Increased day-by-day blood pressure (BP) variability is also known to be associated with stroke; however, little is known on the association between day-by-bay BP variability and aortic arch atherosclerosis in patients with aortic stenosis. Our objective was to clarify the association between day-by-day BP variables (average values and variability) and aortic arch atherosclerosis in patients with severe aortic stenosis. MethodsThe study population consisted of 104 consecutive patients (mean age 75 ± 8 years) with severe aortic stenosis who were scheduled for aortic valve replacement. BP was measured in the morning in at least 4 consecutive days (mean 6.8 days) prior to the day of surgery. Large (≥4 mm), ulcerated, or mobile plaques were defined as complex plaques using transesophageal echocardiography. ResultsCigarette smoking and all systolic BP variables were associated with the presence of complex plaques (p < 0.05), whereas diastolic BP variables were not. Multiple regression analysis indicated that day-by-day mean systolic BP and day-by-day systolic BP variability remained independently associated with the presence of complex plaques (p < 0.05) after adjustment for age, male sex, cigarette smoking, hypertension, hypercholesterolemia, and diabetes mellitus. ConclusionsThese findings suggest that higher day-by-day mean systolic BP and day-by-day systolic BP variability are associated with complex plaques in the aortic arch and consequently stroke risk in patients with aortic stenosis.

Predictors of silent brain infarction on magnetic resonance imaging in patients with nonvalvular atrial fibrillation: A transesophageal echocardiographic study

Silent brain infarction (SBI) is often found in patients with atrial fibrillation (AF) and may be related to cognitive decline. We investigated the predictors of SBI on brain magnetic resonance imaging (MRI) using transesophageal echocardiography (TEE) in patients with nonvalvular AF. The study population consisted of 103 neurologically asymptomatic patients with nonvalvular AF who underwent TEE before transcatheter AF ablation (76 men; mean age 63 ± 10 years). Left atrial (LA) abnormalities such as LA thrombus, spontaneous echo contrast, or abnormal LA appendage emptying velocity (<20 cm/s) and complex plaques in the aortic arch defined as large plaques ≥4 mm thickness, ulcerated plaques, or mobile plaques were evaluated by TEE. All patients were screened for SBI by brain MRI. Of 103 patients, 31 (30%) showed SBI on brain MRI. Most lesions were multiple (61%) and small (<15 mm) in diameter (84%). Patients with SBI had a higher prevalence of LA abnormalities (45% vs 14%; P < .001) and complex arch plaques (45% vs 7%; P < .001) compared with those without SBI. In a multivariate logistic regression analysis including age and CHADS2 score ≥2, LA abnormalities (odds ratio 4.13; 95% CI 1.34-12.72; P = .014) and complex arch plaques (odds ratio 4.82; 95% CI 1.23-18.92; P = .024) were independent predictors of SBI. Left atrial abnormalities and complex arch plaques detected by TEE were closely associated with the presence of SBI on brain MRI, suggesting that microembolization of small thrombi derived from the fibrillating LA or advanced aortic atherosclerotic lesions may be important causes of SBI in patients with nonvalvular AF.

Abstract T P180: Ultrasound Characteristics of Symptomatic Carotid Plaques: A Systematic Review and Meta-analysis

Background and Purpose: Ultrasound is the most commonly used imaging modality for assessment of carotid artery stenosis. A number of studies have demonstrated that surface irregularities, heterogeneous echotexture and hypoechoic plaques are risk factors for acute ischemic stroke. We performed a systematic review and meta-analysis of the literature to better define the risk of stroke based off of the sonographic characteristics of carotid plaques. Materials and Methods: We performed a comprehensive literature search evaluating the association of carotid plaque characteristics on ultrasound with ischemic outcomes. We included both case-control and cohort studies examining the relationship between complex plaque and acute ischemic stroke. Complex plaque was defined as plaque that had any of the following characteristics: heterogeneous plaque echogenicity, hypoechoic plaque, plaque neovascularization, plaque surface irregularity, plaque ulceration, and intraplaque motion. Meta-analyses using the random-effects model were performed for complex plaque and each of the individual complex plaque characteristics. Results: A total of 1013 articles were screened and 30 studies with 11528 patients (3054 symptomatic and 8474 asymptomatic) were included. The odds ratios for the association between complex plaque and ischemic symptoms was 5.18 (95%CI=4.63-5.79). Heterogeneous echotexture (OR=11.72, 95%CI=9.82-13.98), intraplaque motion (OR=1.57, 95%CI=1.02-2.41), plaque echolucency (OR=3.23, 95%CI=2.72-3.84), plaque neovascularity (OR=5.66, 95%CI=3.15-10.16) and plaque ulceration (OR=2.65, 95%CI=1.89-3.73) were all associated with ischemic symptoms. Surface irregularity without frank ulceration was not associated with ischemic symptoms (OR=1.35, 95%CI=0.98-1.86). Conclusions: Complex plaque, heterogeneous plaque echogenicity, hypoechoic plaque, plaque neovascularization, plaque ulceration and intraplaque motion are associated with ischemic symptoms. Assessment of carotid plaque on ultrasound provides stroke risk information beyond measurement of luminal stenosis.

Real-Time Tissue Elastography for the Detection of Vulnerable Carotid Plaques in Patients Undergoing Endarterectomy: A Pilot Study

We examined the utility of ultrasonic real-time tissue elastography (RTE) and conventional B-mode ultrasound (US) in the detection of vulnerable carotid atherosclerotic plaques. This prospective study comprised 19 patients scheduled for carotid endarterectomy. Results obtained from pre-operative RTE and B-mode US and post-operative pathology were compared. RTE encoded low, average and high deformability as blue, green and red, respectively. Tissue hardness was scored on a 5-point scale, and relative strains were calculated. The relative strain was 1.12 ± 0.14 for fibrous plaques (n = 4), 0.28 ± 0.07 for atherosclerotic plaques (n = 5), 0.47 ± 0.31 for intraplaque hemorrhage/thrombosis (n = 5) and 0.98 ± 1.04 for complex plaques (n = 5). The sensitivity, specificity and accuracy of detection of vulnerable plaques were 25%, 100% and 84.2% for B-mode US, 50%, 100% and 89.4% for RTE and 62.5%, 100% and 94.7% for the combination. Ultrasonic RTE is a potential candidate for a non-invasive and effective approach to identify vulnerable atherosclerotic plaques in the carotid artery.

Prevalence of Potential Retrograde Embolization Pathways in the Proximal Descending Aorta in Stroke Patients and Controls

Background: Retrograde diastolic blood flow in the proximal descending aorta (DAo) connecting complex plaques (≥4 mm thick) with brain-supplying supra-aortic arteries may constitute a source of stroke. Yet, data only from high-risk populations (cryptogenic stroke patients with aortic atheroma ≥3 mm) regarding the prevalence of this potential stroke mechanism are available. We aimed to quantify the frequency of this mechanism in unselected patients with cryptogenic stroke after routine diagnostics and controls without a history of stroke. Methods: 88 patients (67 stroke patients, 21 cardiac controls) were prospectively included. 3D T1-weighted bright blood MRI of the aorta was applied for the detection of complex DAo atheroma. ECG-triggered and navigator-gated 4D flow MRI allowed measuring time-resolved 3D blood flow in vivo. Potential retrograde embolization pathways were defined as the co-occurrence of complex plaques and retrograde blood flow in the DAo reaching the outlet of (a) the left subclavian artery, (b) the left common carotid artery, or/and (c) the brachiocephalic trunk. The frequency of these pathways was analyzed by importing 2D plaque images into 3D blood flow visualization software. Results: Complex DAo plaques were more frequent in stroke patients (44 in 31/67 patients (46.3%) vs. 5 in 4/21 controls (19.1%); p = 0.039), especially in older patients (29/46 (63.04%) patients ≥60 years of age with 41 plaques vs. 2/21 (9.14%) patients <60 years of age with 3 plaques; p < 0.001). Contrary to our assumption, retrograde diastolic blood flow at the DAo occurred in every patient irrespective of the existence of plaques with a similar extent in both groups (26 ± 14 vs. 32 ± 18 mm; p = 0.114). Therefore, only the higher prevalence of complex DAo plaques in stroke patients resulted in a three times higher frequency of potential retrograde embolization pathways compared to controls (22/67 (32.8%) vs. 2/21 (9.5%) controls; p = 0.048). Conclusions: This study revealed that retrograde flow in the descending aorta is a common phenomenon not only in stroke patients. The existence of potential retrograde embolization pathways depends mainly on the occurrence of complex plaques in the area 0 to ∼30 mm behind the outlet of the left subclavian artery, which is exposed to flow reversal. In conclusion, we have shown that the frequency of potential retrograde embolization pathways was significantly higher in stroke patients suggesting that this mechanism may play a role in retrograde brain embolism.

Echogenicity of Medium-to-Large Carotid Plaques Predicts Future Vascular Events

Background: Although the echolucent plaque in carotid stenosis is associated with future ischemic stroke, the predictive value of echogenicity in small and medium size carotid plaques on vascular events has not been thoroughly examined. Thus, we prospectively tested the hypothesis that plaque echogenicity of carotid atheroma can predict the future total cardiovascular events in patients with vascular risk factors. Methods: Ultrasound assessment of carotid intima-media complex thickness (IMT) and plaque echogenicity using integrated backscatter (IBS) analysis was performed in 596 patients aged 40 or more, with any history of vascular events or with at least 1 risk factor, who were enrolled between 2001 and 2006 in the Osaka Follow-up Study for Carotid Atherosclerosis, part 2 (OSACA2). We followed the incidence of total cardiovascular events including cerebrovascular events, coronary heart disease (CHD), and peripheral artery disease (PAD) for 6.4 years. We divided the patients into two groups according to the IBS index above (echorich plaques) and under (echolucent plaque) the median value, and calculated the hazard ratios (HR) of the echolucent group compared with the echogenic group in the risk of cardiovascular events. Results: Among 596 patients, carotid stenosis was found only in 87 patients. During the follow-up period, we observed 121 cardiovascular events including 63 cerebrovascular events, 45 CHD cases, and 13 PAD cases. The patients with incident cardiovascular events had larger plaque thickness and lower IBS index than those without incident vascular events. The relative risk of vascular events for echolucent versus echorich plaques was 1.45 (95% confidence interval [CI] 0.99-2.13, p = 0.058) after adjustment for risk factors and plaque thickness. In patients with plaque size above the median value (>2.1 mm), the relative risk of vascular events for echolucent plaques was 1.72 (95% CI 1.06-2.85, p = 0.029), but this association was not observed in patients with plaque size <2.0 mm. Conclusions: The association between echogenicity of carotid plaque and incident vascular events is dependent on the plaque size. Echolucent medium-to-large plaques, but not small plaques, are associated with the risk of future total cardiovascular events. This finding suggests that measurement of echolucency in medium-to-large carotid plaques may improve selection of patients at high risk for total vascular events.

Abstract 12944: Patients With Acute Coronary Syndrome, Compared to Those With Stable Angina Pectoris, Have Increased Bright Spots at the Culprit Site by Optical Coherence Tomography

Background: Recent studies reported that bright spots detected by optical coherence tomography (OCT) represent more complex plaques including macrophages and cholesterol crystals. We hypothesized that the density and area of bright spots would be greater at the culprit lesion in patients with acute coronary syndrome (ACS) compared to those with stable angina pectoris (SAP). Aim: To compare the density and extent of bright spots in the culprit lesion between patients with ACS and with SAP. Methods: We identified 14 ACS and 17 SAP patients who underwent pre-PCI OCT imaging of the culprit lesion. Cases with poor image quality or left main disease were excluded. Bright spots within superficial 125μm of the vessel wall were identified in a 5mm length segment at the culprit site. The density was calculated as the number of bright pixels identified by the algorithm divided by the number of pixels in each frame (total 25 frames in one case). The area of bright spots was also calculated. Results: There were no significant differences in the baseline characteristics including mean age (65.9 ± 10.2 vs 65.2 ± 9.32 yrs, P=0.83) and the prevalence of coronary risk factors between ACS and SAP. Mean and maximum density of bright spots was significantly greater in ACS than in SAP (Table). The area of bright spots was also significantly larger in ACS. Among ACS patients, a subgroup with plaque rupture (n=11) had much greater mean density and area compared with SAP (1.20 [0.41-1.73] vs 0.44 [0.21-0.58], P=0.01, 5.32 [1.88-8.07] vs 2.06 [0.97-2.64], P=0.01). Conclusions: Using the novel algorithm, we demonstrate that the density and area of bright spots are significantly greater in ACS than in SAP. This result suggests that the measurement of bright spots can be useful to determine plaque vulnerability.

Association between chronic kidney disease and thoracic aortic atherosclerosis detected using transesophageal echocardiography

Objective: Accelerated atherosclerosis occurs with a high frequency in patients with chronic kidney disease (CKD). We evaluated the association between CKD and thoracic aortic plaques using transesophageal echocardiography (TEE). Methods: This study population consisted of 297 patients who underwent TEE. Aortic plaques were evaluated in the proximal thoracic aorta (PTA) (from the ascending aorta to the aortic arch) and the distal thoracic aorta (DTA) (the descending aorta) using TEE. Aortic plaques were defined as complex plaques of ≥4 mm thickness and with ulceration or mobile components. CKD was defined as the estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. The association between CKD and aortic plaques was evaluated using multivariate analysis after adjusting for traditional atherosclerotic risk factors. Results: Patients with CKD (n = 144) had a higher incidence of any plaques and complex plaques compared with those without CKD (n = 153) (85% vs. 47% and 42% vs. 17%, respectively, both P < 0.001). Univariate analysis indicated that the presence of CKD was significantly associated with complex plaques both in the DTA and the PTA (both, P < 0.001); however, multivariate analysis indicated that the presence of CKD was associated with only complex plaques in the DTA (P < 0.05), but not with those in the PTA. Conclusion: The presence of CKD was associated with complex aortic plaques, with this association being stronger for complex plaques in the DTA than those in the PTA.

Intérêt de l’échocardiographie trans-œsophagienne dans l’optimisation de la stratégie thérapeutique après un accident vasculaire cérébral ischémique

Aim of the studyIn the setting of ischemic stroke, the place of transesophageal echocardiography (TEE) is still matter of debate. The aim of the study is to evaluate the therapeutic impact provided by TEE and to characterize patients in whom TEE is warranted. Patients and methodThree hundred and fifty-nine consecutive patients were included in the study. “Decisive TEE” (DTEE) was defined by echographic findings resulting in a change of treatment, whereas “informative TEE” (ITEE) was defined by TEE revealing a potential cardiac or aortic source of embolism. ResultsThree hundred and forty-one patients underwent TEE. Twenty-eight patients (8.2%) had DTEE and 184 (53.9%) had ITEE. DTEE were as follows: thrombus in the left atrial appendage in 6 patients, complex aortic plaques in 10 patients, patent foramen ovale (PFO) associated with atrial septal aneurism (ASA) and an important right to left shunt (3 patients), FOP associated with ASA and lower limb phlebitis (1 patient), 4 cases of endocarditis and 4 patients with intense spontaneous echo contrast in the left atrium. In most cases of DTEE (67.8%), the patient was given anticoagulation drugs. Left atrial dilatation (P=0.005) and multivessel territory stroke (P=0.018) were statistically predictive of DTEE. ConclusionsIn the setting of ischemic stroke, TEE provides important additional informations, but modifies therapeutic strategy in less than 10% of cases. Multivessel territory stroke, and left atrial dilatation were predictive of DTEE.

New Perspectives in the Management of Aortic Intramural Hematoma – a literature review

Abstract Aortic intramural hematoma frequently appear in elderly hypertensive patients who suffered a vasa vasorum rupture into the media, presenting clinical symptoms similar to aortic dissection. The current available data suggest a similar treatment strategy as in aortic dissection, although intramural hematoma is a different pathophysiological entity. The issue of the vulnerable contact of the intraaortic plaque, which is prone to rupture and to trigger the formation of an intramural hematoma, has not been elucidated so far. We present a brief literature review regarding complex plaque analysis, which opens a new area in identification of vulnerable patients with intramural hematoma, important for management of these patients and optimization of their treatment in order to avoid complications.

Factors associated with complex plaques in thoracic and abdominal aorta detected by MRI

Factors associated with complex plaques in thoracic and abdominal aorta detected by MRI

Detecting atheromatous plaques in the aortic arch or supra-aortic arteries for more accurate stroke subtype classification

Introduction. To investigate the correlations of atheromatous plaques in the aortic arch or supra-aortic arteries with intracranial arterial stenosis and carotid plaques in stroke patients, and to determine whether taking these plaques into account will reduce the proportion of patients in the undetermined etiology group. Methods. We prospectively enrolled 308 ischemic stroke patients, whose clinical characteristics and A-S-C-O classifications were compared with analyses of intracranial arteries, carotid arteries, aortic arch, and supra-aortic arteries. Results. 125(40.6%) patients had plaques in the aortic arch or supra-aortic arteries, of which 106 (84.8%) had complex plaques. No correlations were observed between these plaques and carotid plaques ( p = 0.283) or intracranial arterial stenosis ( p = 0.097). After detecting the mobile thrombi in the aortic arch and supra-aortic arteries, the proportion of patients in the atherothrombosis group was increased from 33.8% to 55.5% ( p = 0.00), whereas the proportion of patients in stroke of undetermined etiology group was decreased from 19.2% to 11.0% ( p = 0.00). Discussion. Examining only the carotid and intracranial arteries may not provide adequate information about large arteries in stroke patients. Therefore, it would be better to include a search for relevant plaques in the aortic arch or supra-aortic arteries in modern stroke workup, for it may lead to more accurate stroke subtype classification and guide secondary prevention.