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Serial Echocardiography (serial + echocardiography)
Selected AbstractsLong-Term Evaluation of Myoblast Seeded Patches Implanted on Infarcted Rat HeartsARTIFICIAL ORGANS, Issue 6 2010Marie-Noėlle Giraud Abstract Cell transplantation presents great potential for treatment of patients with severe heart failure. However, its clinical application was revealed to be more challenging than initially expected in experimental studies. Further investigations need to be undertaken to define the optimal treatment conditions. We previously reported on the epicardial implantation of a bio-engineered construct of skeletal myoblast-seeded polyurethane and its preventive effect on progression toward heart failure. In the present study, we present a long-term evaluation of this functional outcome. Left anterior descending coronary ligation was performed in female Lewis rats. Two weeks later, animals were treated with either epicardial implantation of biograft, acellular scaffold, sham operation, or direct intramyocardial skeletal myoblast injection. Functional assessments were performed with serial echocardiographies every 3 months and end point left ventricle pressure was assessed. Hearts were then harvested for histological examinations. Myocardial infarction induced a slow and progressive reduction in fractional shortening after 3 months. Progression toward heart failure was significantly prevented for up to 6 months after injection of myoblasts and for up to 9 months following biograft implantation. Nevertheless, this effect vanished after 12 months, with immunohistological examinations revealing an absence of the transplanted myoblasts within the scaffold. We demonstrated that tissue therapy is superior to cell therapy for stabilization of heart function. However, beneficial effects are transient. [source] Resting Echocardiography for the Early Detection of Acute Coronary Syndromes in Chest Pain Unit PatientsECHOCARDIOGRAPHY, Issue 6 2010Vito Maurizio Parato M.D. Aim: The purpose of this study is to assess the ability of resting echocardiography to detect an acute coronary syndrome (ACS) before the occurrence of ischemic electrocardiogram (ECG) changes or troponin-T elevations. Methods: Four hundred and three patients who presented to the emergency room (ER) with chest pain, normal ECGs, and normal troponin-T levels were admitted to the cardiologist-run Chest Pain Unit (CPU) for further monitoring. They underwent serial resting echocardiography for monitoring of left ventricle wall motion (LVWM), ECG telemetry monitoring, and serial troponin-T measurements. Results: An ACS was detected in 49 patients (12.1%). These 49 patients were then subdivided into three different groups based on the initial mode of detection of their ACS. In group A, 16 of 49 (32.6%) patients had ACS shown by echocardiographic detection of LVWM abnormalities. In group B, 24 of 49 (48.9%) patients had an ACS detected by ischemic ECG changes. In group C, 9 of 49 (18.3%) patients had an ACS detected by troponin-T elevations. The shortest time interval between CPU-admission and ACS-detection occurred in group A (A vs. B, P < 0.003; A vs. C, P < 0.0001). In group A, cardiac angiogram showed that the culprit coronary lesion was more frequent in the circumflex artery (11 out of 16; 68.7%) (LCx vs. LAD, P < 0.02; LCx vs. RCA, P < 0.001) and of these 11 patients with circumflex lesions, the ECG was normal in eight (72.7%) patients. Conclusion: This study demonstrates the utility of LVWM monitoring by serial echocardiography as part of a diagnostic protocol that can be implemented in a CPU. Furthermore, echocardiography could become an essential tool used in the diagnosis of ACS secondary to circumflex lesions. (Echocardiography 2010;27:597-602) [source] Effects of trimetazidine, a partial inhibitor of fatty acid oxidation, on ventricular function and survival after myocardial infarction and reperfusion in the ratFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 4 2010Frederic Mouquet Abstract Trimetazidine (TMZ), a partial inhibitor of fatty acid oxidation, has been effective in treating chronic angina, but its effects on the development of post-myocardial infarction (MI) left ventricular remodeling are not defined. In this study, we tested whether chronic pre-MI administration of TMZ would be beneficial during and after acute MI. Two-hundred male Wistar rats were studied in four groups: sham + TMZ diet (n = 20), sham + control diet (n = 20), MI + TMZ diet (n = 80), and MI + control diet (n = 80) splitted into one short-term and one long-term experiments. Sham surgery consisted of a thoracotomy without coronary ligation. MI was induced by coronary occlusion followed by reperfusion. Left ventricle (LV) function and remodeling were assessed by serial echocardiography throughout a 24-week post-MI period. LV remodeling was also assessed by quantitative histological analysis of post-MI scar formation at 24 weeks post-MI. During the short-term experiment, 10/80 rats died after MI, with no difference between groups (MI + control = 7/40, MI + TMZ = 3/40, P = 0.3). In the long-term experiment, the deaths occurred irregularly over the 24 weeks with no difference between groups (MI + control = 16% mortality, MI + TMZ = 17%, P = 0.8). There was no difference between groups as regard to LV ejection fraction (MI + control = 36 ± 13%, MI + TMZ = 35 ± 13%, P = 0.6). In this experimental model, TMZ had no effects on the post-MI occurrence of LV dysfunction or remodeling. Further investigations are warranted to assess whether the partial inhibition of fatty acid oxidation may limit the ability of the heart to respond to acute severe stress. [source] Critical Role for IL-6 in Hypertrophy and Fibrosis in Chronic Cardiac Allograft RejectionAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2009J. A. Diaz Chronic cardiac allograft rejection is the major barrier to long term graft survival. There is currently no effective treatment for chronic rejection except re-transplantation. Though neointimal development, fibrosis, and progressive deterioration of graft function are hallmarks of chronic rejection, the immunologic mechanisms driving this process are poorly understood. These experiments tested a functional role for IL-6 in chronic rejection by utilizing serial echocardiography to assess the progression of chronic rejection in vascularized mouse cardiac allografts. Cardiac allografts in mice transiently depleted of CD4+ cells that develop chronic rejection were compared with those receiving anti-CD40L therapy that do not develop chronic rejection. Echocardiography revealed the development of hypertrophy in grafts undergoing chronic rejection. Histologic analysis confirmed hypertrophy that coincided with graft fibrosis and elevated intragraft expression of IL-6. To elucidate the role of IL-6 in chronic rejection, cardiac allograft recipients depleted of CD4+ cells were treated with neutralizing anti-IL-6 mAb. IL-6 neutralization ameliorated cardiomyocyte hypertrophy, graft fibrosis, and prevented deterioration of graft contractility associated with chronic rejection. These observations reveal a new paradigm in which IL-6 drives development of pathologic hypertrophy and fibrosis in chronic cardiac allograft rejection and suggest that IL-6 could be a therapeutic target to prevent this disease. [source] Effect of lifestyle factors and hormone therapy on heart function by serial echocardiography in postmenopausal womenAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 1 2010Soo-Keat KHOO Background:, There is conflicting information on the effects of oestrogen on the heart in women, especially those using postmenopausal hormone therapy. Whilst some studies reported a beneficial effect, others showed adverse outcomes. The interplay of lifestyle factors and type/timing of therapy remains to be clarified. Aim:, The aim of this study was to determine the effects of lifestyle and hormone therapy on heart function and structure in postmenopausal women. Method:, As part of a large longitudinal study of women randomly recruited from an urban population, the study assessed 410 suitable women by echocardiography in Year 1 and Year 5 of the study by two independent cardiologists. Results:, In lifestyle characteristics, the difference in age and body mass (as markers of cardiovascular risk) was in favour of never-users versus hormone therapy-users. Using an arbitrary cut-off ,15% change for an effect, we found lifestyle factors had minimal effect on the two measured parameters , ejection fraction, left ventricular mass. Effects of hormone therapy were variable and mixed; greatest effect was found for an ,early start' of hormone therapy with oestrogen-only preparation , the risk of reduced ejection fraction was decreased [hazard ratio (HR) 0.42, confidence interval = 0.17,1.03, P = 0.06] and risk of increased left ventricular mass was increased (HR 2.21, 1.09,4.49, P = 0.03). Conclusion:, Our findings add to the evidence that oestrogen given to postmenopausal women has a mixed effect on the heart, with effect best shown when started early. [source] | ||||||||||