Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2022 Aug 8;28(4):891–911. doi: 10.1089/ten.teb.2021.0088

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© Tori Salem, et al., 2022; Published by Mary Ann Liebert, Inc.

This Open Access article is distributed under the terms of the Creative Commons License [CC-BY] (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PMC Copyright notice

FIG. 4. — The tissue-level physiology of the human heart. The composition of the heart is varied based on position. (A) The heart has various subcomponents, including vasculature, the pericardium, neuronal innervation, and the endocardium. (C) Fibroblasts regulate the extracellular matrix of the heart, which is primarily composed of collagen I and III, elastin, and laminin. (B) The bulk of the heart is composed of the myocardium which by volume, is primarily composed of cardiomyocytes. The myocardium is heavily vascularized by capillaries, and other cell types are dispersed throughout. (D) The cell density of the human heart is highly variable, with neonatal human hearts having more than 10 times the cell density of mature hearts. Color images are available online.