Imaging of atherosclerosis: magnetic resonance imaging

Atherosclerosis and its thrombotic complications are the major cause of morbidity and mortality in the industrialized countries. Despite advances in our understanding of the pathophysiology, pathogenesis, and new treatment modalities, the absence of an adequate non-invasive imaging tool for early detection limits both the prevention and treatment of patients with various degrees and anatomical localizations of atherothrombotic disease. An ideal clinical imaging modality for atherosclerotic vascular disease should be safe, inexpensive, non-invasive or minimally invasive, accurate, and reproducible, and the results should correlate with the extent of atherosclerotic disease and have high predictive values for future clinical events. High-resolution magnetic resonance imaging (MRI) has emerged as the most promising technique for studying atherothrombotic disease in humans in vivo. Most importantly, MRI allows for the characterization of plaque composition, i.e. the discrimination of lipid core, fibrosis, calcification, and intraplaque haemorrhage deposits. Magnetic resonance imaging also allows for the detection of arterial thrombi and in defining thrombus age. Magnetic resonance imaging has been used to monitor plaque progression and regression in several animal models of atherosclerosis and in humans. Emerging MRI techniques capable of imaging biological processes, including inflammation, neovascularization, and mechanical forces, may aid in advancing our understanding of the atherothrombotic disease. Advances in diagnosis do prosper provided they march hand-in-hand with advances in treatment. We stand at the threshold of accurate non-invasive assessment of atherosclerosis. Thus, MRI opens new strategies ranging from screening of high-risk patients for early detection and treatment as well as monitoring of the target lesions for pharmacological intervention. Identification of subclinical atherosclerosis and early treatment initiation has the potential to surpass conventional risk factor assessment and management in terms of overall impact on cardiovascular morbidity and mortality. Such strategy is currently under clinical investigatio

Atherosclerosis regression and TP receptor inhibition: effect of S18886 on plaque size and composition—a magnetic resonance imaging study

Aims Endothelial dysfunction, platelet hyperactivity, and inflammation play a crucial role in atherogenesis. A growing body of evidence suggests that inhibition of the thromboxane A2 (TxA2 or TP) receptor may improve endothelial function and reduce the inflammatory component of atherosclerosis in addition to its demonstrated antiplatelet activity. Consequently, we sought to assess the effect of a novel TP receptor antagonist S18886, on atherosclerotic lesion progression and composition by serial non-invasive magnetic resonance imaging (MRI). Methods and results S18886 was compared with control in an experimental model of established aortic atherosclerosis in New Zealand White rabbits (n=10). The animals underwent MRI of the abdominal aorta at the time of randomization and at the end of treatment. Subsequently, animals were euthanized and specimens were stained for histopathology and immunohistochemistry with anti-α-actin antibodies for vascular smooth muscle cells (VSMC), anti-RAM-11 for macrophages, anti-caspase-3 for apoptotic cells, anti-MMP-1 for metalloproteinases, and anti-endothelin-1 (ET-1) as a marker of endothelial dysfunction. MRI analysis revealed a significant reduction in total vessel area (TVA) and vessel wall area (VWA) in the S18886 group (P<0.05). Immunostaining analysis showed a significant decrease in RAM-11, caspase-3, MMP-1, ET-1 and an increase in α-actin in the treated group (P<0.05 vs. control). Conclusion Inhibition of the TP receptor by S18886 causes a regression of advanced atherosclerotic plaques. In addition, the reduction in the markers for macrophages, apoptotic cells, metalloproteinases, and endothelin-1 and the increase in VSMC, suggests that S18886 may not only halt the progression of atherosclerosis, but also transform lesions towards a more stable phenotype. The possibility of combining antithrombotic and antiatherosclerotic activity by means of the administration of TP inhibitors deserves further investigation in a clinical settin

Lp(a): Are Antithrombotic Therapies the Key to Event Reduction?

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The CNIC: A Successful Vision in Cardiovascular Research

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The Intima-Media Thickness Age Is Over: The Time of Multiterritorial Subclinical Plaque Quantification Has Come.

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Tropical Cardiovascular Diseases: The Forgotten Orphans.

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Polypill strategy at the heart of cardiovascular secondary prevention

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Barriers and Facilitators to Nurse Management of Hypertension: A Qualitative Analysis from Western Kenya

BACKGROUND: Hypertension is the leading global risk for mortality. Poor treatment and control of hypertension in low- and middle-income countries is due to several reasons, including insufficient human resources. Nurse management of hypertension is a novel approach to address the human resource challenge. However, specific barriers and facilitators to this strategy are not known. OBJECTIVE: To evaluate barriers and facilitators to nurse management of hypertensive patients in rural western Kenya, using a qualitative research approach. METHODS: Six key informant interviews (five men, one woman) and seven focus group discussions (24 men, 33 women) were conducted among physicians, clinical officers, nurses, support staff, patients, and community leaders. Content analysis was performed using Atlas.ti 7.0, using deductive and inductive codes that were then grouped into themes representing barriers and facilitators. Ranking of barriers and facilitators was performed using triangulation of density of participant responses from the focus group discussions and key informant interviews, as well as investigator assessments using a two-round Delphi exercise. RESULTS: We identified a total of 23 barriers and nine facilitators to nurse management of hypertension, spanning the following categories of factors: health systems, environmental, nurse-specific, patient-specific, emotional, and community. The Delphi results were generally consistent with the findings from the content analysis. CONCLUSION: Nurse management of hypertension is a potentially feasible strategy to address the human resource challenge of hypertension control in low-resource settings. However, successful implementation will be contingent upon addressing barriers such as access to medications, quality of care, training of nurses, health education, and stigma

Motivational interview and imaging of subclinical atherosclerosis for cardiovascular disease prevention: a winning combination?

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