Recent developments in cardiac pacing and trans-coronary vein ablations have demonstrated the increasing value of imaging of the cardiac venous system (CVS), especially computed tomographic (CT) mapping of the coronary veins. In contrast to that for coronary arteries, the literature for coronary veins is scarce. Moreover, a complete, highly efficient, and clinically useful classification of the CVS is not as straightforward as for the coronary arteries. The CVS comprises polymorphous types of venous conduits with notable anatomic variations. Recent anatomic classification divides the cardiac veins into two main groups: tributaries of the greater CVS and tributaries of the lesser CVS, consisting of the thebesian vessels. The greater CVS is subdivided into two groups: coronary sinus and non-coronary sinus tributaries. Imaging information about the CVS in this review is useful for a better understanding of the spatial orientation of the CVS and furthers proper use of the correct nomenclature for this important system. The authors describe the clinical implications of the different imaging techniques for assessment of the coronary veins, where cardiac CT venous mapping has major advantages. The role of CT in anatomic classification, assessment of anatomic variants, and diagnosis of pathologic changes of the CVS is discussed. The authors also underscore the particular role of CT venous mapping for cardiac interventions, especially for left ventricular pacing in cardiac resynchronization therapy and in percutaneous mitral annuloplasty.
NADPH oxidase (Nox)-derived reactive oxygen species (ROS) are instrumental in all inflammatory phases of atherosclerosis. Dysregulated histone deacetylase (HDAC)-related epigenetic pathways have been mechanistically linked to alterations in gene expression in experimental models of cardiovascular disorders. Hitherto, the relation between HDAC and Nox in atherosclerosis is not known. We aimed at uncovering whether HDAC plays a role in mediating Nox up-regulation, oxidative stress, inflammation, and atherosclerotic lesion progression. Human non-atherosclerotic and atherosclerotic arterial samples, ApoE−/− mice, and in vitro polarized monocyte-derived M1/M2-macrophages (Mac) were examined. Male ApoE−/− mice, maintained on normal or high-fat, cholesterol-rich diet, were randomized to receive 10 mg/kg suberoylanilide hydroxamic acid (SAHA), a pan-HDAC inhibitor, or its vehicle, for 4 weeks. In the human/animal studies, real-time PCR, Western blot, lipid staining, lucigenin-enhanced chemiluminescence assay, and enzyme-linked immunosorbent assay were employed. The protein levels of class I, class IIa, class IIb, and class IV HDAC isoenzymes were significantly elevated both in human atherosclerotic tissue samples and in atherosclerotic aorta of ApoE−/− mice. Treatment of ApoE−/− mice with SAHA reduced significantly the extent of atherosclerotic lesions, and the aortic expression of Nox subtypes, NADPH-stimulated ROS production, oxidative stress and pro-inflammatory markers. Significantly up-regulated HDAC and Nox subtypes were detected in inflammatory M1-Mac. In these cells, SAHA reduced the Nox1/2/4 transcript levels. Collectively, HDAC inhibition reduced atherosclerotic lesion progression in ApoE−/− mice, possibly by intertwined mechanisms involving negative regulation of Nox expression and inflammation. The data propose that HDAC-oriented pharmacological interventions could represent an effective therapeutic strategy in atherosclerosis.
A number of criteria are used in the literature to describe high take-off coronary arteries, which can in part, explain the divide in the literature on the pathological significance of this anomaly. This study presents the anatomical variations of high take-off coronary arteries to draw attention to the possible clinical implications they may cause during angiography and other surgical procedures. The English Literature was searched to review high take-off coronary arteries. A high take-off coronary artery arising at least 1 cm in adults or 20% the depth of the sinus in children above the sinutubular junction, is considered of greater clinical relevance and was included in our meta-analysis. High take-off coronaries by other criteria was also included as part of the comprehensive review. Exclusion criteria were reports made in case studies or case reviews. The prevalence of high take-off coronary arteries in our study was 26 of 12,899 (0.202%). High take-off coronary arteries were found to originate up to 5 cm above the sinutubular junction. Right coronary arteries made up 84.46% of high take-off coronary arteries reported in the literature. Three (0.023%) cases that originated more than one centimeter above the sinutubular junction was associated with sudden cardiac death. This is a higher reported association than in studies that used other criteria for classification. It is important for clinicians to recognize the importance of correctly diagnosing high take-off coronary arteries in patients with coexisting cardiac morbidities so that suitable management plans can be developed.
The fibrous skeleton is concentrated at the base of the ventricular mass. It provides electrical insulation at the atrioventricular level and fibrous continuity for the leaflets of the mitral, aortic, and tricuspid valves. Its components include the fibrous trigones, the fibrous area of aortic-mitral continuity, the subvalvar collar of the mitral valve, the membranous septum, the interleaflet triangles, the tendon of Todaro, and likely the conus ligament. The majority of the mitral annulus is fibrous, but the only true fibrous part of the tricuspid annulus is where the valvar leaflets are attached to the central fibrous body. At the aortic annulus, the fibrous elements support only the noncoronary aortic sinus and parts of the right and left coronary sinuses. The ring-shaped annulus of the arterioventricular valves as localized with imaging techniques (imaging annulus) differs from the crown-shaped hemodynamic annulus of the arterial valves. The imaging annulus corresponds to the plane passing through the nadirs of the hinge-lines of the leaflets. The hinges of the pulmonary valve are not part of the fibrous skeleton. Computed tomography (CT) and magnetic resonance (MR) imaging are excellent modalities for evaluation of the anatomy, physiologic variations, and pathologic conditions of the fibrous skeleton. The submillimeter isotropic three-dimensional datasets obtained with CT and the high contrast resolution of MR imaging are the main advantages of these modalities in assessing anatomy. The function of the valves and associated annuli can best be studied with MR imaging. Pathologic conditions involving the area, including paravalvar leaks, abscesses, perforation, and pseudoaneurysms, usually occur as a complication of infective endocarditis or extensive calcifications after valvar surgery. MR imaging and CT can demonstrate these lesions equally well. CT is the preferred technique for showing the extent of calcifications in the fibrous skeleton. Large calcifications involving the central fibrous body can cause heart block by interfering with the normal function of the His bundle and its branches. RSNA, 2017.
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