Evidence for intermittent coupling of intramyocardial small, engineered heart tissues acutely implanted into rabbit myocardium.

Aims: Electrical integration of human iPSC-derived cardiomyocyte (hiPSC-CM)-based tissue with the host myocardium is a requirement of successful regeneration therapy. This study was designed to identify electrical coupling in the acute phase (1-2h) post-grafting using an ex vivo model.

Methods And Results: Small, engineered heart tissues (mini-EHTs) consisting of ∼50,000 hiPSC-CMs on a hydrogel (spontaneous rate 0.

Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes for Preclinical Cardiotoxicity Screening in Cardio-Oncology.

• hiPSC-CM offer an alternative to in vivo models for predicting cardiotoxicity. • hiPSC-CM monolayers detect pro-arrhythmic effects; inotropic detection is less established. • Cardiac spheroids and engineered tissue may suit chronic cardiotoxicity studies (>2 weeks).

A novel method for the percutaneous induction of myocardial infarction by occlusion of small coronary arteries in the rabbit.

Arrhythmic sudden cardiac death (SCD) is an important cause of mortality following myocardial infarction (MI). The rabbit has similar cardiac electrophysiology to humans and is therefore an important small animal model to study post-MI arrhythmias. The established approach of surgical coronary ligation results in thoracic adhesions that impede epicardial electrophysiological studies.

Conventional rigid 2D substrates cause complex contractile signals in monolayers of human induced pluripotent stem cell-derived cardiomyocytes.

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) in monolayers interact mechanically via cell-cell and cell-substrate adhesion. Spatiotemporal features of contraction were analysed in hiPSC-CM monolayers (1) attached to glass or plastic (Young's modulus (E) >1 GPa), (2) detached (substrate-free) and (3) attached to a flexible collagen hydrogel (E = 22 kPa). The effects of isoprenaline on contraction were compared between rigid and flexible substrates.

Customizable, engineered substrates for rapid screening of cellular cues.

Biophysical cues robustly direct cell responses and are thus important tools for in vitro and translational biomedical applications. High throughput platforms exploring substrates with varying physical properties are therefore valuable. However, currently existing platforms are limited in throughput, the biomaterials used, the capability to segregate between different cues and the assessment of dynamic responses.