They observed clear changes at the capillary level in the hearts, affecting the tiny blood vessels in the heart muscle tissue – revealing a network full of splits, branches and loops that had been “chaotically remodelled by the formation and splitting of new vessels,” according to a release.

These changes are the first direct visuals of the damage COVID-19 can cause in the body, which is known as “intussusceptive angiogenesis” or new vessel formation in the tissue, according to the release.

In order to have such detailed 3D imaging of the capillary network, researchers had to painstakingly, manually label all of the image data so that a computer could render it using machine-learning methods.

"The parameters obtained from this then showed a completely different quality compared to healthy tissue, or even to diseases such as severe influenza or common myocarditis," said study leaders Tim Salditt and Danny Jonigk in the release.

The study says that their process could be done in other clinics to support doctors with routine diagnostics. In the future, researchers want to expand the use of synchrotron radiation to help create automated tools for diagnosing patients with other diseases.