Injectable and conductive cardiac patch

Introduction: Previously we have demonstrated that a tissue engineered heart patch comprised of human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) and fibroblasts improves both left ventricular (LV) systolic and diastolic function in a rat model of CHF. In this study we tested the feasibility of upscaling cardiac patch size and surgical deployment in a swine model of CHF to test clinical utility. Methods: Four male Gottingen mini swine 20-25kg and three domestic swine 50-60kg were infarcted using percutaneous methods. Embolizing coils were deployed via catheter distal to the first diagonal branch of the left anterior descending (LAD) coronary artery and animals recovered for 4 weeks. Cardiac patches engineered with bio absorbable polygalactin-910 knitted mesh, dermal fibroblasts and hiPSC-CMs were cultured and implanted on the infarcted epicardium 4 weeks after MI. Cardiac magnetic resonance imaging was performed at baseline, 4 and 8 weeks post MI. All swine were implanted with continuous event recorders to acquire surface electrocardiogram during the entire study. In addition quality of life and functional capacity were assessed through video monitoring and treadmill exertion testing respectively. Infarct size was determined through 2,3,5-triphenyltetrazolium chloride staining. Results: LAD occlusion resulted in a significant (P<0.05) decrease EF (15%), and increase in EDV (59%) and ESV (100%). Average TIMI score decreased from 3.0±0 at time of MI to 1.5±0.6 4wks post MI. Cardiac patches were upsized to 6cm diameter for application in the swine. Patches displayed synchronous and spontaneous contractions within 48hrs. The 6cm patches, when implanted effectively covered the infarcted region bridging viable myocardium. Surgical handling and epicardial deployment was successfully accomplished via median sternotomy. The patches were robust in nature and could be deployed via a minimally invasive robotic procedure. No adverse arrhythmic activity was observed. Implantation of the cardiac patch restored activity levels (quality of life) of patch treated swine vs CHF controls. Conclusion: Our hiPSC-CM cardiac patch can be constructed in a clinical size, easily handled and implanted on the epicardium of the infarcted heart.

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Preliminary results of 24-hour Holter and 7-day single-use, water-resistant, wireless, cardiac patch electrocardiogram monitoring for detecting atrial fibrillation after an acute cerebral ischemic event: A comparative analysis

International Journal of Cardiology ◽

10.1016/j.ijcard.2021.10.033 ◽

2021 ◽

Vol 345 ◽

pp. 2

Author(s):

D.H.P. Foo ◽

W.C. Law ◽

L.Y.Y. Then ◽

K.X. Gan ◽

S.C. Wong ◽

...

Keyword(s):

Atrial Fibrillation ◽

Comparative Analysis ◽

Ischemic Event ◽

Preliminary Results ◽

Single Use ◽

Cerebral Ischemic ◽

Electrocardiogram Monitoring ◽

Cardiac Patch

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Engineered properties of polyurethane laden with beetroot and cerium oxide for cardiac patch application

Journal of Industrial Textiles ◽

10.1177/15280837211054218 ◽

2021 ◽

pp. 152808372110542

Author(s):

Saravana Kumar Jaganathan ◽

Mohan Prasath Mani ◽

Ahmad Fauzi bin Ismail ◽

Ahmad Zahran Mohd Khudzari ◽

Ahmad Athif Mohd Faudzi

Keyword(s):

Cerium Oxide ◽

Infrared Analysis ◽

Hemolysis Assay ◽

Force Microscopy ◽

Patch Application ◽

Atomic Force ◽

Coagulation Study ◽

Afm Analysis ◽

Hydrophobic Nature ◽

Cardiac Patch

The cardiac patch provides appropriate physicochemical properties and mechanical strength for the regeneration of damaged heart tissues. In this work, for the first-time, beetroot (BR) is blended with cerium oxide (CeO2) to produce nanofibrous polyurethane (PU) composite patch using electrospinning. The objective of this work is to fabricate the composite and examine its feasibility for cardiac patch applications. Morphological analysis revealed a dramatic reduction of fiber diameter of PU/BR (233 ± 175 nm) and PU/BR/CeO2 (331 ± 176 mm) compared to the pristine PU (994 ± 113 mm). Fourier transform infrared analysis (FTIR) analysis indicated functional peak intensities of the newly formed composite PU/BR and PU/BR/CeO2 were not similar to PU. The addition of beetroot rendered PU/BR hydrophilic (86° ± 2), whereas PU/BR/CeO2exhibited hydrophobic nature (99° ± 3). Atomic force microscopy (AFM) analysis depicted the reduced surface roughness of the PU/BR (312 ± 12 nm) and PU/BR/CeO2 (390 ± 125 nm) than the pristine PU (854 ± 32 nm). The incorporation of beetroot and CeO2 into PU enhanced the tensile strength compared with the pristine PU. The blood clotting time of PU/BR (APTT-204 ± 3 s and PT-103 ± 2 s) and PU/BR/CeO2 (APTT-205 ± 3 s and PT-105 ± 2s) were delayed significantly than the pristine PU(APTT-176 ± 2 s and PT-94 ± 2 s) as revealed in the coagulation study. Further, hemolysis assay showed the less toxic nature of the fabricated composites than the pristine PU. Hence, it can be inferred that the advanced physicochemical and blood compatible properties of electrospun PU/BR and PU/BR/CeO2 nanocomposite can be engineered successfully for cardiac patch applications.

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