High‐Throughput Scaffold System for Studying the Effect of Local Geometry and Topology on the Development and Orientation of Sprouting Blood Vessels

Live tissues require vascular networks for cell nourishing. Mimicking the complex structure of native vascular networks in vitro requires understanding the governing factors of early tubulogenesis. Current vascularization protocols allow for spontaneous formation of vascular networks; however, there is still a need to provide control over the defined network structure. Moreover, there is little understanding on sprouting decision and migration, especially within 3D environments. Here, tessellated polymer scaffolds with various compartment geometries and a novel two‐step seeding protocol are used to study vessel sprouting decisions. Endothelial cells first organize into hollow vessels tracing the shape contour with high fidelity. Subsequent sprouts emerge in specific directions, responding to compartment geometry. Time‐lapse imaging is used to track vessel migration, evidencing that sprouts frequently emerge from the side centers, mainly migrating toward opposing corners, where the density of support cells (SCs) is the highest, providing the highest levels of angiogenic factors. SCs distribution is quantified by smooth muscle actin expression, confirming the cells preference for curved compartment surfaces and corners. Displacements within the hydrogel correlate with SCs distribution during the initial tubulogenesis phase. This work provides new insight regarding vessel sprouting decisions that should be considered when designing scaffolds for vascularized engineered tissues.A novel two‐step cell seeding on tesselated scaffolds produces highly organized and oriented vessel networks. Different compartment shapes promote vessel sprouting with specific orientations according to the compartment geometry and encourage distinct support cell distributions. Vessels depart from areas with low support cell concentration (side between corners) and are drawn to areas with higher concentration of support cells (corners).Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155501/1/adfm201901335-sup-0001-S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155501/2/adfm201901335.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155501/3/adfm201901335_am.pd

Evolution of right and left ventricle routine and speckle-tracking echocardiography in patients recovering from coronavirus disease 2019: a longitudinal study

AIMS: We aim to assess changes in routine echocardiographic and longitudinal strain parameters in patients recovering from Coronavirus disease 2019 during hospitalization and at 3-month follow-up. METHODS AND RESULTS: Routine comprehensive echocardiography and STE of both ventricles were performed during hospitalization for acute coronavirus disease 2019 (COVID-19) infection as part of a prospective pre-designed protocol and compared with echocardiography performed ∼3 months after recovery in 80 patients, using a similar protocol. Significantly improved right ventricle (RV) fractional area change, longer pulmonary acceleration time, lower right atrial pressure, and smaller RV end-diastolic and end-systolic area were observed at the recovery assessment (P < 0.05 for all). RV global longitudinal strain improved at the follow-up evaluation (23.2 ± 5 vs. 21.7 ± 4, P = 0.03), mostly due to improvement in septal segments. Only eight (10%) patients recovering from COVID-19 infection had abnormal ejection fraction (EF) at follow-up. However, LV related routine (E, E/e', stroke volume, LV size), or STE parameters did not change significantly from the assessment during hospitalization. A significant proportion [36 (45%)] of patients had some deterioration of longitudinal strain at follow-up, and 20 patients (25%) still had abnormal LV STE ∼3 months after COVID-19 acute infection. CONCLUSION: In patients previously discharged from hospitalization due to COVID-19 infection, RV routine echocardiographic and RV STE parameters improve significantly concurrently with improved RV haemodynamics. In contrast, a quarter of patients still have LV systolic dysfunction based on STE cut-offs. Moreover, LV STE does not improve significantly, implying subclinical LV dysfunction may be part and parcel of recovering from COVID-19 infection

Longitudinal diastolic strain slope as an early sign for systolic dysfunction among patients with active cancer

BACKGROUND: Diastolic dysfunction is a common finding in patients receiving cancer therapy. This study evaluated the correlation of diastolic strain slope (Dss) with routine echocardiography diastolic parameters and its role in early detection of systolic dysfunction and cardiovascular (CV) mortality within this population. METHODS: Data were collected from the Israel Cardio-Oncology Registry (ICOR), a prospective registry enrolling adult patient receiving cancer therapy. All patients performed at least three echocardiography exams (T1, T2, T3), including left ventricle Global Longitudinal Strain (LV GLS) and Dss. Systolic dysfunction was determined by either LV GLS relative reduction of ≥ 15% or LV ejection fraction reduction > 10% to < 53%. Dss was assessed as the early lengthening rate, measured by the diastolic slope (delta%/sec). RESULTS: Among 144 patients, 114 (79.2%) were female with a mean age of 57.31 ± 14.3 years. Dss was significantly correlated with e' average. Mid segment Dss change between T1 and T2 showed significant association to systolic dysfunction development (Odds Ratio (OR) = 1.04 [1.01,1.06]. p = 0.036). In multivariate prediction, Dss increase was a significant predictor for the development of systolic dysfunction (OR = 1.06 [1.03,1.1], P < 0.001).An 8% increase in Dss between T1 and T2 was associated with a trend in increased CV mortality (HR = 3.4 [0.77,15.4], p = 0.085). CONCLUSIONS: This study is the first to use the novel measurement of Dss in patients treated with cancer therapies and to show significant correlation between routine diastolic dysfunction parameters and Dss. Changes in the mid segment were found to have significant independent early predictive value for systolic dysfunction development in univariate and multivariate analyses