Fig. 1

Functions of different cell types in a failing heart. Heart failure is a complex process that involves multiple cell types in the heart. Under stress, cardiomyocytes undergo either pathological hypertrophy or cell death. Hypertrophy led to cardiomyocyte dysfunction, while non-programmed or programmed cell death led to cardiomyocyte loss. Cardiac fibrosis is another form of cardiac remodeling. It mainly involves fibroblast activation and conversion to myofibroblast. Various immune cells also contribute to heart failure. These cells infiltrate the injured myocardium, secret cytokines, and cleared unwanted material to regulate inflammation, regeneration, and function of other cell types in the failing heart. Both vascular endothelial cells (VECs) and lymphatic endothelial cells (LECs) regulate cardiac function. VECs affect neighboring cardiac cells by paracrine factors. LECs regulate cardiac regeneration after infarction by maintaining fluid balance, promoting immune cell clearance, and also secreting paracrine factors