Istaroxime is a first-in-class agent which acts through inhibition of the sarcolemmal Na + /K + pump and activation of the SERCA2a pump. This study assessed the effects of a 24 h infusion of istaroxime in patients hospitalised for acute heart failure (AHF).

Background: The performance of left ventricular (LV) functional assessment using gated myocardial perfusion SPECT (MPS) relies on the accuracy of segmentation. Current methods require manual adjustments that are tedious and subjective. We propose a novel machine-learning-based method to automatically segment LV myocardium and measure its volume in gated MPS imaging without human intervention. Methods: We used an end-to-end fully convolutional neural network to segment LV myocardium by delineating its endocardial and epicardial surface. A novel compound loss function, which encourages similarity and penalizes discrepancy between prediction and training dataset, is utilized in training stage to achieve excellent performance. We retrospectively investigated 32 normal patients and 24 abnormal patients, whose LV myocardial contours automatically segmented by our method were compared with those delineated by physicians as the ground truth. Results: The results of our method demonstrated very good agreement with the ground truth. The average DSC metrics and Hausdorff distance of the contours delineated by our method are larger than 0.900 and less than 1cm, respectively, among all 32+24 patients of all phases. The correlation coefficient of the LV myocardium volume between ground truth and our results is 0.910±0.061 (P<0.001), and the mean relative error of LV myocardium volume is-1.09±3.66%. Conclusion: These results strongly indicate the feasibility of our method in accurately quantifing LV myocardium volume change over the cardiac cycle. The learning-based segmentation method in gated MPS imaging has great promise for clinical use.

MBF and reserve measurements using (99m)Tc-sestamibi on a traditional, two-headed camera with fast rotation and with quantitative dynamic SPECT appears to be feasible, warranting further investigation.

Induced pluripotent stem (iPS) cells have the potential to differentiate to various types of cardiovascular cells to repair an injured heart. The potential therapeutic benefits of iPS cell based treatment have been established in small-animal models of myocardial infarction (MI). We hypothesize that porcine iPS (piPS) cell transplantation may be an effective treatment for MI. After a 90-minute occlusion of the left anterior descending artery in a porcine model, undifferentiated piPS cells or PBS were injected into the ischemic myocardium. Cardiac function, myocardial perfusion and cell differentiation were investigated. One week after piPS cell delivery, global left ventricular ejection fraction (LVEF) significantly decreased in both the iPS group and the PBS group compared to the Sham group (p<0.05, respectively). Six weeks after piPS cell delivery, LVEF of the iPS group significantly improved compared to the PBS group (56.68% vs. 50.93%, p = 0.04) but was still lower than the Sham group. Likewise, the piPS cell transplantation improved the regional perfusion compared to the PBS injection (19.67% vs. 13.67%, p = 0.02). The infarct area was significantly smaller in the iPS group than the PBS group (12.04% vs. 15.98% p = 0.01). PiPS cells engrafted into the myocardium can differentiate into vessel cells, which result in increased formation of new vessels in the infarcted heart. Direct intramyocardial injection of piPS cells can decrease infarct size and improve left ventricular function and perfusion for an immunosuppressed porcine AMI model.