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This paper presents multiview and multiframe active appearance models (AAMs) for left ventricular segmentation in triplane echocardiograms. We describe a general way of integrating local edge detector based segmentation algorithms into the AAM framework. The feasibility of this approach is evaluated by comparing an AAM constrained by a dynamic programming (DP) based snake with an unconstrained AAM, and an AAM constrained by manually defined landmarks. A leave-one-out validation scheme was used for training and testing of the methods. Evaluation was done in 36 patients suffering from various heart diseases, using manually determined volumes and ejection fractions (EF) as reference. The segmentation was initialized by manual selection of the mitral annulus and apex in three imaging planes. The differences, in volume, between manual segmentation and the best automatic method (DP-constrained AAM) were -3.1 [+ or -] 20 ml (mean [+ or -] SD) at end-diastole and 0.61 [+ or -] 13 ml at end-systole. The difference in EF was -1.3 [+ or -] 6.3 %, comparable to the interobserver variability. We show that 1) constraining the model to manually defined landmarks improves volume and EF estimates compared to unconstrained AAMs, 2) further improvement is achieved using a DP-constrained AAM, and 3) segmentation in triplane echocardiograms gives higher accuracy than single plane data. Index Terms--Active appearance models (AAMs), dynamic programming, left ventricular segmentation, triplane echocardiography.

A randomized, controlled trial, known as the Autologous Stem-Cell Transplantation in Acute Myocardial Infarction (ASTAMI) study, was conducted to investigate whether intracoronary injection of autologous mononuclear bone marrow (BMC) results in a clinically important improvement in left ventricular function as measured by the left ventricular ejection factor (LVEF). Results showed no effects of intracoronary injection of autologous mononuclear BMC on global left ventricular function.

Cardiac allograft vasculopathy (CAV) remains a leading cause of long‐term mortality after heart transplantation. Both preventive measures and treatment options are limited. This study aimed to evaluate the short‐term effects of high‐intensity interval training (HIT) on CAV in de novo heart transplant (HTx) recipients as assessed by optical coherence tomography (OCT). The study population was a subgroup of the 81‐patient HITTS study in which HTx recipients were randomized to HIT or moderate intensity continuous training (MICT) for nine consecutive months. OCT images from baseline and 12 months were compared to assess CAV progression. The primary endpoint was defined as the change in the mean intima area. Paired OCT data were available for 56 patients (n = 23 in the HIT group and n = 33 in the MICT group). The intima area in the entire study population increased by 25% [from 1.8±1.4 mm2 to 2.3±2.0 mm2, P <.05]. The change was twofold higher in the MICT group (.6±1.2 mm2) than in the HIT group (.3±.6 mm2). However, the treatment effect of HIT was not significant (treatment effect = –.3 mm2, 95% CI [–.825 to.2 mm2] P =.29). These results suggest that early initiation of HIT compared with MICT does not attenuate CAV progression in de novo HTx recipients. [ABSTRACT FROM AUTHOR]

Abstract Background The aim of the present study was to compare circulating levels of selected prothrombotic markers in patients suffering acute myocardial infarction (AMI) with and without left ventricular (LV) thrombus. Methods One hundred patients with AMI treated with PCI on the LAD and dual antiplatelet therapy were included. LV thrombus formation was detected by echocardiography and/or MRI in 15 patients. Fasting blood samples were drawn 4–5 days (baseline), 6–7 days, 8–9 days, 2–3 weeks and 3 months after the AMI for determination of haemostatic markers. Results We found higher levels of soluble tissue factor (TF) and D-dimer in the LV thrombus group 4–5 days, 8–9 days and 3 months (only TF) after the AMI compared to the patients without thrombus formation (p The levels of prothrombin fragment 1+2 (F1+2) and endogenous thrombin potential (ETP) were significantly lower in the thrombus group after 8–9 days (only ETP), 2–3 weeks and 3 months. The levels of plasminogen activator inhibitor 1 activity and tissue plasminogen activator antigen did not differ between the groups. Conclusion In the acute phase of AMI, we found higher levels of TF and D-dimer in the LV thrombus group, indicating hypercoagulability of possible importance for the generation of mural thrombus. Lower levels of F1+2, ETP and D-dimer in the thrombus group late during follow-up are probably induced by the initiated anticoagulation therapy.

Abstract Background Trials have brought diverse results of bone marrow stem cell treatment in necrotic myocardium. This substudy from the Autologous Stem Cell Transplantation in Acute Myocardial Infarction trial (ASTAMI) explored global and regional myocardial function after intracoronary injection of autologous mononuclear bone marrow cells (mBMC) in acute anterior wall myocardial infarction treated with percutaneous coronary intervention. Methods Cardiovascular magnetic resonance (CMR) tagging was performed 2-3 weeks and 6 months after revascularization in 15 patients treated with intracoronary stem cell injection (mBMC group) and in 13 controls without sham injection. Global and regional left ventricular (LV) strain and LV twist were correlated to cine CMR and late gadolinium enhancement (LGE). Results In the control group myocardial function as measured by strain improved for the global LV (6 months: -13.1 ± 2.4 versus 2-3 weeks: -11.9 ± 3.4%, p = 0.014) and for the infarct zone (-11.8 ± 3.0 versus -9.3 ± 4.1%, p = 0.001), and significantly more than in the mBMC group (inter-group p = 0.027 for global strain, respectively p = 0.009 for infarct zone strain). LV infarct mass decreased (35.7 ± 20.4 versus 45.7 ± 29.5 g, p = 0.024), also significantly more pronounced than the mBMC group (inter-group p = 0.034). LV twist was initially low and remained unchanged irrespective of therapy. Conclusions LGE and strain findings quite similarly demonstrate subtle differences between the mBMC and control groups. Intracoronary injection of autologous mBMC did not strengthen regional or global myocardial function in this substudy. Trial registration ClinicalTrials.gov: NCT00199823

Abstract Background Recent studies have shown that real-time three-dimensional (3D) echocardiography (RT3DE) gives more accurate and reproducible left ventricular (LV) volume and ejection fraction (EF) measurements than traditional two-dimensional methods. A new semi-automated tool (4DLVQ) for volume measurements in RT3DE has been developed. We sought to evaluate the accuracy and repeatability of this method compared to a 3D echo standard. Methods LV end-diastolic volumes (EDV), end-systolic volumes (ESV), and EF measured using 4DLVQ were compared with a commercially available semi-automated analysis tool (TomTec 4D LV-Analysis ver. 2.2) in 35 patients. Repeated measurements were performed to investigate inter- and intra-observer variability. Results Average analysis time of the new tool was 141s, significantly shorter than 261s using TomTec (p < 0.001). Bland Altman analysis revealed high agreement of measured EDV, ESV, and EF compared to TomTec (p = NS), with bias and 95% limits of agreement of 2.1 ± 21 ml, -0.88 ± 17 ml, and 1.6 ± 11% for EDV, ESV, and EF respectively. Intra-observer variability of 4DLVQ vs. TomTec was 7.5 ± 6.2 ml vs. 7.7 ± 7.3 ml for EDV, 5.5 ± 5.6 ml vs. 5.0 ± 5.9 ml for ESV, and 3.0 ± 2.7% vs. 2.1 ± 2.0% for EF (p = NS). The inter-observer variability of 4DLVQ vs. TomTec was 9.0 ± 5.9 ml vs. 17 ± 6.3 ml for EDV (p < 0.05), 5.0 ± 3.6 ml vs. 12 ± 7.7 ml for ESV (p < 0.05), and 2.7 ± 2.8% vs. 3.0 ± 2.1% for EF (p = NS). Conclusion In conclusion, the new analysis tool gives rapid and reproducible measurements of LV volumes and EF, with good agreement compared to another RT3DE volume quantification tool.