Genome-Wide Analyses Reveal a Role for Peptide Hormones in Planarian Germline Development

Genomic/peptidomic analyses of the planarian Schmidtea mediterranea identifies >200 neuropeptides and uncovers a conserved neuropeptide required for proper maturation and maintenance of the reproductive system

User-initialized active contour segmentation and golden-angle real-time cardiovascular magnetic resonance enable accurate assessment of LV function in patients with sinus rhythm and arrhythmias

BACKGROUND: Data obtained during arrhythmia is retained in real-time cardiovascular magnetic resonance (rt-CMR), but there is limited and inconsistent evidence to show that rt-CMR can accurately assess beat-to-beat variation in left ventricular (LV) function or during an arrhythmia. METHODS: Multi-slice, short axis cine and real-time golden-angle radial CMR data was collected in 22 clinical patients (18 in sinus rhythm and 4 patients with arrhythmia). A user-initialized active contour segmentation (ACS) software was validated via comparison to manual segmentation on clinically accepted software. For each image in the 2D acquisitions, slice volume was calculated and global LV volumes were estimated via summation across the LV using multiple slices. Real-time imaging data was reconstructed using different image exposure times and frame rates to evaluate the effect of temporal resolution on measured function in each slice via ACS. Finally, global volumetric function of ectopic and non-ectopic beats was measured using ACS in patients with arrhythmias. RESULTS: ACS provides global LV volume measurements that are not significantly different from manual quantification of retrospectively gated cine images in sinus rhythm patients. With an exposure time of 95.2 ms and a frame rate of > 89 frames per second, golden-angle real-time imaging accurately captures hemodynamic function over a range of patient heart rates. In four patients with frequent ectopic contractions, initial quantification of the impact of ectopic beats on hemodynamic function was demonstrated. CONCLUSION: User-initialized active contours and golden-angle real-time radial CMR can be used to determine time-varying LV function in patients. These methods will be very useful for the assessment of LV function in patients with frequent arrhythmias

Quantification of CTEPH Disease Burden on CT Angiogram Correlates with Patient Presurgical Hemodynamic Severity and Hemodynamic Improvement after PTE Surgery.

PURPOSE:To evaluate the relationship between the burden of chronic thromboembolic disease quantified via CT pulmonary angiography and pre-operative hemodynamics and post-operative hemodynamic improvement in CTEPH patients undergoing PTE. METHODS:CTEPH patients who underwent pulmonary thromboendarterectomy surgery (PTE) between December 2017 and August 2019 were retrospectively screened for having 1) preoperative CT pulmonary angiogram (CTPAs) with corresponding preoperative vascular annotations, 2) preoperative right heart catheterization, 3) bilateral level 2 surgical disease (defined from surgically resected thromboembolic specimen) and 4) recorded postoperative hemodynamics. Clot burden was quantified in preoperative CTPAs using the Qanadli score, which weights the location and severity of thromboembolic lesions into a per-patient score. Mean pulmonary artery pressure, pulmonary vascular resistance, and total pulmonary resistance were obtained from right heart catheterization preoperatively and then on the day of Swan-Ganz removal in the ICU postoperatively. Linear regression was performed between measured clot burden and hemodynamic variables. Continuous variables are presented as mean ± standard deviation. RESULTS:15 patients (7 females, age: 36 ± 13 years, BMI: 35.0 ± 6.7, preoperative mPAP: 40 ± 13 mmHg) met all inclusion criteria. Clot burden score ranged from 11 to 30, with a mean of 19 ± 6. Level of surgical disease seen on imaging matched surgical findings in 87% and 67% of cases (right and left lungs, respectively). Figure 1 illustrates the significant linear correlations between clot burden and preoperative mPAP (R2= 0.59), PVR (R2 = 0.69) and TPR (R2= 0.58), as well as post PTE improvement in PVR (R2 = 0.48) and TPR (R2 = 0.35). CONCLUSION:Pre-operative CT-based quantitative assessment of the pulmonary vasculature is associated with the hemodynamic severity of CTEPH and surgical improvement in PVR after PTE

Novel 4DCT Method to Measure Regional Left Ventricular Endocardial Shortening Before and After Transcatheter Mitral Valve Implantation

BackgroundRegional left ventricular (LV) mechanics in mitral regurgitation (MR) patients, and local changes in function after transcatheter mitral valve implantation (TMVI) have yet to be evaluated. Herein, we introduce a method for creating high resolution maps of endocardial function from 4DCT images, leading to detailed characterization of changes in local LV function. These changes are particularly interesting when evaluating the effect of the Tendyne™ TMVI device in the region of the epicardial pad.MethodsRegional endocardial shortening from CT (RSCT) was evaluated in Tendyne (Abbott Medical) TMVI patients with 4DCT exams pre- and post-implantation. Regional function was evaluated in 90 LV segments (5 longitudinal × 18 circumferential). LV volumes and ejection fraction (EF) were also computed. A reproducibility study was performed in a subset of patients to determine the precision of RSCT measurements in this population.ResultsBaseline and local changes in RSCT post TMVI were highly variable and extremely spatially heterogeneous. Both inter- and intra-observer variability were low and demonstrated the high precision of RSCT for evaluating regional LV function.ConclusionRSCT is a reproducible metric which can be evaluated in patients with highly abnormal regional LV function and geometry. After TMVI, significant spatially heterogeneous changes in RSCT were observed in all subjects; therefore, it is unlikely that the functional state of TMVI patients can be fully described by changes in LV volume or EF. Measurement of RSCT provides precise characterization of the spatially heterogeneous effects of MR and TMVI on LV function and remodeling

Three-dimensional ultrasound-derived physical mitral valve modeling.

PurposeAdvances in mitral valve repair and adoption have been partly attributed to improvements in echocardiographic imaging technology. To educate and guide repair surgery further, we have developed a methodology for fast production of physical models of the valve using novel three-dimensional (3D) echocardiographic imaging software in combination with stereolithographic printing.DescriptionQuantitative virtual mitral valve shape models were developed from 3D transesophageal echocardiographic images using software based on semiautomated image segmentation and continuous medial representation algorithms. These quantitative virtual shape models were then used as input to a commercially available stereolithographic printer to generate a physical model of the each valve at end systole and end diastole.EvaluationPhysical models of normal and diseased valves (ischemic mitral regurgitation and myxomatous degeneration) were constructed. There was good correspondence between the virtual shape models and physical models.ConclusionsIt was feasible to create a physical model of mitral valve geometry under normal, ischemic, and myxomatous valve conditions using 3D printing of 3D echocardiographic data. Printed valves have the potential to guide surgical therapy for mitral valve disease

Three-dimensional ultrasound-derived physical mitral valve modeling.

PurposeAdvances in mitral valve repair and adoption have been partly attributed to improvements in echocardiographic imaging technology. To educate and guide repair surgery further, we have developed a methodology for fast production of physical models of the valve using novel three-dimensional (3D) echocardiographic imaging software in combination with stereolithographic printing.DescriptionQuantitative virtual mitral valve shape models were developed from 3D transesophageal echocardiographic images using software based on semiautomated image segmentation and continuous medial representation algorithms. These quantitative virtual shape models were then used as input to a commercially available stereolithographic printer to generate a physical model of the each valve at end systole and end diastole.EvaluationPhysical models of normal and diseased valves (ischemic mitral regurgitation and myxomatous degeneration) were constructed. There was good correspondence between the virtual shape models and physical models.ConclusionsIt was feasible to create a physical model of mitral valve geometry under normal, ischemic, and myxomatous valve conditions using 3D printing of 3D echocardiographic data. Printed valves have the potential to guide surgical therapy for mitral valve disease