Scientists find COVID-19 directly infects heart tissue, causing damage

Researchers from the Centenary Institute and the University of Technology Sydney have discovered that SARS-CoV-2 can directly invade heart tissue, replicate inside it, and cause inflammatory changes associated with impaired myocardial function, according to a study published in the journal Biofabrication.

The team used so-called cardiac spheroids—tiny “mini-hearts” composed of three-dimensional clusters of cells that mimic the structure and behavior of real heart tissue more closely than standard lab cultures. Using this 3D system, scientists demonstrated that SARS-CoV-2 can infect and actively replicate within heart tissue.

In contrast, isolated heart cell types grown separately did not show the same ability to support viral replication, suggesting that the spatial organization of cells and their interactions play a key role in tissue damage.

According to the authors, these findings help explain why some COVID-19 patients experience serious heart complications during or after infection, even without prior diagnosed heart conditions. The most common issues include myocarditis (inflammation of the heart muscle), arrhythmia, thrombosis, and cardiomyopathy—heart failure accompanied by changes in ventricular volume.

Researchers say the cardiac spheroid model could serve as a tool for testing protective strategies against viral infections and developing new therapies, both for COVID-19 and other viruses with potential cardiotoxic effects.

By Jeyhun Aghazada