87 research outputs found

    Left Ventricular Structure and Function Basic Science for Cardiac Imaging

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    The myofiber geometry of the left ventricle (LV) changes gradually from a right-handed helix in the subendocardium to a left-handed helix in the subepicardium. In this review, we associate the LV myofiber architecture with emerging concepts of the electromechanical sequence in a beating heart. We discuss: 1) the morphogenesis and anatomical arrangement of muscle fibers in the adult LV; 2) the sequence of depolarization and repolarization; 3) the physiological inhomogeneity of transmural myocardial mechanics and the apex-to-base sequence of longitudinal and circumferential deformation; 4) the sequence of LV rotation; and 5) the link between LV deformation and the intracavitary flow direction observed during each phase of the cardiac cycle. Integrating the LV structure with electrical activation and motion sequences observed in vivo provides an understanding about the spatiotemporal sequence of regional myocardial performance that is essential for noninvasive cardiac imaging

    European survey on valvular heart disease clinical experience from the European Society of Cardiology council on valvular heart disease.

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    editorial reviewedAIMS: The aim of this survey is to analyze how current recommendations on valvular heart disease (VHD) management have been adopted. Identifying potential discrepancies between recommendations and everyday clinical practice would enable us to better understand and address the remaining challenges in this controversial and complex field. METHODS AND RESULTS: A total of 33 questions, distributed via email to all European Society of Cardiology (ESC) affiliated countries through the newsletter of the ESC council on VHD, were answered by 689 respondents, mainly from tertiary care settings. The results of this survey showed that VHD patients are mostly managed by tertiary care centres, where multi-disciplinary heart teams are frequently a reality. Cardiac computed tomography (CT) is often used in the preprocedural planning of transcatheter interventions, particularly for sizing and deliverability assessment. Echocardiography represents the most widely used imaging modality in the diagnostic, intra-operative and follow-up phase of VHD patients. Cardiac magnetic resonance (CMR) is still largely underused, also for conditions such as mitral annular disjunction, or for the assessment of left ventricle volumes where it is considered as the gold standard, despite 3D volumes by echocardiography having proved good comparability with CMR. As for endocarditis, despite still underused, transesophageal echocardiography (TEE) represents the approach of choice for the diagnosis of native and prosthesis valve endocarditis (up to 46% of the respondents use it). In this context, positron emission tomography-CT is largely underused. CONCLUSION: There is widespread adoption of current recommendation on the evaluation of VHD and these are frequently used to guide patient management. Nonetheless, there are still many discrepancies across centres and countries which need to be addressed with the aim of improving patients' management and outcomes and ultimately positively impacting on healthcare resources

    Molecular Imaging for Efficacy of Pharmacologic Intervention in Myocardial Remodeling

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    ObjectivesUsing molecular imaging techniques, we examined interstitial alterations during postmyocardial infarction (MI) remodeling and assessed the efficacy of antiangiotensin and antimineralocorticoid intervention, alone and in combination.BackgroundThe antagonists of the renin-angiotensin-aldosterone axis restrict myocardial fibrosis and cardiac remodeling after MI and contribute to improved survival. Radionuclide imaging with technetium-99m–labeled Cy5.5 RGD imaging peptide (CRIP) targets myofibroblasts and indirectly allows monitoring of the extent of collagen deposition post-MI.MethodsCRIP was intravenously administered for gamma imaging after 4 weeks of MI in 63 Swiss-Webster mice and in 6 unmanipulated mice. Of 63 animals, 50 were treated with captopril (C), losartan (L), spironolactone (S) alone, or in combination (CL, SC, SL, and SCL), 8 mice received no treatment. Echocardiography was performed for assessment of cardiac remodeling. Hearts were characterized histopathologically for the presence of myofibroblasts and thick and thin collagen fiber deposition.ResultsAcute MI size was similar in all groups. The quantitative CRIP percent injected dose per gram uptake was greatest in the infarct area of untreated control mice (2.30 ± 0.14%) and decreased significantly in animals treated with 1 agent (C, L, or S; 1.71 ± 0.35%; p = 0.0002). The addition of 2 (CL, SC, or SL 1.31 ± 0.40%; p < 0.0001) or 3 agents (SCL; 1.16 ± 0.26%; p < 0.0001) demonstrated further reduction in tracer uptake. The decrease in echocardiographic left ventricular function, strain and rotation parameters, as well as histologically verified deposition of thin collagen fibers, was significantly reduced in treatment groups and correlated with CRIP uptake.ConclusionsRadiolabeled CRIP allows for the evaluation of the efficacy of neurohumoral antagonists after MI and reconfirms superiority of combination therapy. If proven clinically, molecular imaging of the myocardial healing process may help plan an optimal treatment for patients susceptible to heart failure
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