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Adjuvant radiation therapy in breast cancer is a standard of care, either post-lumpectomy or in case of lymph node involvement. Internal mammary chain (IMC) is more and more included in the clinical target volume, because it increases overall survival. This increase must be weighed against cardiac complications in left breast cancer. Intensity modulated radiation therapy (IMRT) is used in this indication in order to better cover target volumes, but tends to increase irradiated healthy volumes, including the heart. The average cardiac dose is higher with IMRT, while it is also predictive of cardiovascular events in patients treated in 3D. This article aims to make an inventory of the IMC irradiations, as well as a review of the mechanisms of radiation-induced cardiac toxicity and ways to diagnose it early. Cooperation between medical oncologists, radiotherapy oncologists and cardiologists is needed to better support patients., (Copyright © 2019 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.)

Diagnosing and localizing myocardial infarct is crucial for early patient management and therapy planning. We propose a new method for predicting the location of myocardial infarct from local wall deformation, which has value for risk stratification from routine examinations such as (3D) echocardiography. The pipeline combines non-linear dimensionality reduction of deformation patterns and two multi-scale kernel regressions. Confidence in the diagnosis is assessed by a map of local uncertainties, which integrates plausible infarct locations generated from the space of reduced dimensionality. These concepts were tested on 500 synthetic cases generated from a realistic cardiac electromechanical model, and 108 pairs of 3D echocardiographic sequences and delayed-enhancement magnetic resonance images from real cases. Infarct prediction is made at a spatial resolution around 4 mm, more than 10 times smaller than the current diagnosis, made regionally. Our method is accurate, and significantly outperforms the clinically-used thresholding of the deformation patterns (on real data: sensitivity/specificity of 0.828/0.804, area under the curve: 0.909 versus 0.742 for the most predictive strain component). Uncertainty adds value to refine the diagnosis and eventually re-examine suspicious cases.

We propose a new approach for the generation of synthetic but visually realistic time series of cardiac images based on an electromechanical model of the heart and real clinical 4-D image sequences. This is achieved by combining three steps. The first step is the simulation of a cardiac motion using an electromechanical model of the heart and the segmentation of the end diastolic image of a cardiac sequence. We use biophysical parameters related to the desired condition of the simulated subject. The second step extracts the cardiac motion from the real sequence using nonrigid image registration. Finally, a synthetic time series of cardiac images corresponding to the simulated motion is generated in the third step by combining the motion estimated by image registration and the simulated one. With this approach, image processing algorithms can be evaluated as we know the ground-truth motion underlying the image sequence. Moreover, databases of visually realistic images of controls and patients can be generated for which the underlying cardiac motion and some biophysical parameters are known. Such databases can open new avenues for machine learning approaches.

Unlabelled: Abnormalities of norepinephrine uptake have been found to reflect impairment in adrenergic nerve function that has influenced the cardiac outcome of patients with heart failure. The aim of this study was to explore the cardiac neuronal function by using 123I-metaiodobenzylguanidine (MIBG) scintigraphy in patients with acute myocarditis., Methods: We studied 15 patients (age range 42 +/- 10 yr) with clinical, biological, electrocardiographic and radionuclide left ventricular ejection fraction (LVEF) (41% +/- 7%) data indicating myocarditis and 10 normal subjects (age range 36 +/- 7 yr, mean radionuclide LVEF 69% +/- 8%, p < 0.05). Fourteen patients had positive histologic findings of myocarditis and 1 had nonspecific histological data. All patients underwent planar cardiac imaging after intravenous injection of 185 MBq 123I-MIBG and right ventricular biopsy within 7 days. A chest anterior view was acquired 4 hr later. Heart-to-mediastinum ratio activity was measured, as previously described in our laboratory., Results: Significant impairment of cardiac neuronal uptake of MIBG was observed and based on a reduction of heart-to-mediastinum ratio (148% +/- 16% versus 234% +/- 36%, p < 0.05). A significant correlation was observed between LVEF and MIBG uptake in patients (y = 1.58x +/- 83.7, r = 0.72, p < 0.01)., Conclusion: Acute myocarditis is associated with an injury of the cardiac adrenergic neuronal function. In addition to the inflammatory injury of the myocytes, the impairment of adrenergic function may be involved in the cardiac pump failure induced by myocarditis.

Quantification of cardiac deformation and strain with 3D ultrasound takes considerable research efforts. Nevertheless, a widespread use of these techniques in clinical practice is still held back due to the lack of a solid verification process to quantify and compare performance. In this context, the use of fully synthetic sequences has become an established tool for initial in silico evaluation. Nevertheless, the realism of existing simulation techniques is still too limited to represent reliable benchmarking data. Moreover, the fact that different centers typically make use of in-house developed simulation pipelines makes a fair comparison difficult. In this context, this paper introduces a novel pipeline for the generation of synthetic 3D cardiac ultrasound image sequences. State-of-the art solutions in the fields of electromechanical modeling and ultrasound simulation are combined within an original framework that exploits a real ultrasound recording to learn and simulate realistic speckle textures. The simulated images show typical artifacts that make motion tracking in ultrasound challenging. The ground-truth displacement field is available voxelwise and is fully controlled by the electromechanical model. By progressively modifying mechanical and ultrasound parameters, the sensitivity of 3D strain algorithms to pathology and image properties can be evaluated. The proposed pipeline is used to generate an initial library of 8 sequences including healthy and pathological cases, which is made freely accessible to the research community via our project web-page. [ABSTRACT FROM AUTHOR]

This paper evaluates five 3D ultrasound tracking algorithms regarding their ability to quantify abnormal deformation in timing or amplitude. A synthetic database of B-mode image sequences modeling healthy, ischemic and dyssynchrony cases was generated for that purpose. This database is made publicly available to the community. It combines recent advances in electromechanical and ultrasound modeling. For modeling heart mechanics, the Bestel–Clement–Sorine electromechanical model was applied to a realistic geometry. For ultrasound modeling, we applied a fast simulation technique to produce realistic images on a set of scatterers moving according to the electromechanical simulation result. Tracking and strain accuracies were computed and compared for all evaluated algorithms. For tracking, all methods were estimating myocardial displacements with an error below 1 mm on the ischemic sequences. The introduction of a dilated geometry was found to have a significant impact on accuracy. Regarding strain, all methods were able to recover timing differences between segments, as well as low strain values. On all cases, radial strain was found to have a low accuracy in comparison to longitudinal and circumferential components. [ABSTRACT FROM PUBLISHER]