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The pericardium, which surrounds the heart, provides a unique enclosed volume and a site for the delivery of agents to the heart and coronary arteries. While strategies for targeting the delivery of therapeutics to the heart are lacking, various technologies and nanodelivery approaches are emerging as promising methods for site specific delivery to increase therapeutic myocardial retention, efficacy, and bioactivity, while decreasing undesired systemic effects. Here, we provide a literature review of various approaches for intrapericardial delivery of agents. Emphasis is given to sustained delivery approaches (pumps and catheters) and localized release (patches, drug eluting stents, and support devices and meshes). Further, minimally invasive access techniques, pericardial access devices, pericardial washout and fluid analysis, as well as therapeutic and cell delivery vehicles are presented. Finally, several promising new therapeutic targets to treat heart diseases are highlighted., (Copyright © 2019. Published by Elsevier B.V.)

Objective: Four-dimensional flow cardiovascular magnetic resonance may improve assessment of hemodynamics in patients with aortic dissection. The purpose of this study was to evaluate the feasibility and accuracy of 4-dimensional flow cardiovascular magnetic resonance assessment of true and false lumens flow., Methods: Thirteen ex vivo porcine aortic dissection models were mounted to a flow loop. Four-dimensional flow cardiovascular magnetic resonance and 2-dimensional phase-contrast cardiovascular magnetic resonance measurements were performed, assessed for intraobserver and interobserver variability, and compared with a reference standard of sonotransducer flow volume measurements. Intraobserver and interobserver variability of 4-dimensional flow cardiovascular magnetic resonance were also assessed in 14 patients with aortic dissection and compared with 2-dimensional phase-contrast cardiovascular magnetic resonance., Results: In the ex vivo model, the intraobserver and interobserver measurements had Lin's correlation coefficients of 0.98 and 0.96 and mean differences of 0.17 (±3.65) mL/beat and -0.59 (±5.33) mL/beat, respectively; 4-dimensional and sonotransducer measurements had a Lin's concordance correlation coefficient of 0.95 with a mean difference of 0.35 (±4.92) mL/beat, respectively. In patients with aortic dissection, the intraobserver and interobserver measurements had Lin's concordance correlation coefficients of 0.98 and 0.97 and mean differences of -0.95 (±8.24) mL/beat and 0.62 (±10.05) mL/beat, respectively; 4-dimensional and 2-dimensional flow had a Lin's concordance correlation coefficient of 0.91 with a mean difference of -9.27 (±17.79) mL/beat because of consistently higher flow measured with 4-dimensional flow cardiovascular magnetic resonance in the ascending aorta., Conclusions: Four-dimensional flow cardiovascular magnetic resonance is feasible in patients with aortic dissection and can reliably assess flow in the true and false lumens of the aorta. This promotes potential future work on functional assessment of aortic dissection hemodynamics., (Copyright © 2018 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

The application of three-dimensional (3D) printing enables the creation of material objects from digital images by depositing layers of plastic material into 3D structures and can be used for training, education, and surgical planning. We report two patients with large complex cardiac tumors where 3D technology was utilized to analyze the tumor size, location, and extension more precisely, allowing better preoperative planning and decision making., (© 2016 Wiley Periodicals, Inc.)

Background: 3D stereolithographic printing can be used to convert high-resolution computed tomography images into life-size physical models. We sought to apply 3D printing technologies to develop patient-specific models of the anatomic and functional characteristics of severe aortic valve stenosis., Methods and Results: Eight patient-specific models of severe aortic stenosis (6 tricuspid and 2 bicuspid) were created using dual-material fused 3D printing. Tissue types were identified and segmented from clinical computed tomography image data. A rigid material was used for printing calcific regions, and a rubber-like material was used for soft tissue structures of the outflow tract, aortic root, and noncalcified valve cusps. Each model was evaluated for its geometric valve orifice area, echocardiographic image quality, and aortic stenosis severity by Doppler and Gorlin methods under 7 different in vitro stroke volume conditions. Fused multimaterial 3D printed models replicated the focal calcific structures of aortic stenosis. Doppler-derived measures of peak and mean transvalvular gradient correlated well with reference standard pressure catheters across a range of flow conditions (r=0.988 and r=0.978 respectively, P<0.001). Aortic valve orifice area by Gorlin and Doppler methods correlated well (r=0.985, P<0.001). Calculated aortic valve area increased a small amount for both methods with increasing flow (P=0.002)., Conclusions: By combing the technologies of high-spatial resolution computed tomography, computer-aided design software, and fused dual-material 3D printing, we demonstrate that patient-specific models can replicate both the anatomic and functional properties of severe degenerative aortic valve stenosis., (© 2015 American Heart Association, Inc.)