Medical researchers find COVID-19 can cause the death of heart cells

One of the health issues associated with the COVID-19 virus since the pandemic began is heart problems. Among the heart problems are reduced ability to pump blood and abnormal heart rhythms. Health professionals have wondered if the heart problems are caused by the virus infecting the heart or an inflammatory response to infection in other parts of the body.

Knowing how the virus relates to heart issues seen with the illness is important for doctors to understand how to treat coronavirus infections that impact the heart. Researchers from Washington University School of Medicine in St. Louis have conducted a new study that found evidence that COVID-19 patients' heart damage is caused by the virus invading and replicating inside heart muscle cells.

The proliferation of the virus inside the heart cells can lead to cellular death and interferes with heart muscle contraction. The research team used stem cells to engineer heart tissue that models the human infection in the study. The results of the study could help researchers study the disease and develop potential therapies.

Early in the pandemic, there was evidence that coronavirus could cause heart failure or damage heart tissue in people who were generally healthy. There were instances of some college athletes cleared to go back to competition after being infected with COVID-19, who later showed scarring in their hearts. The debate over the cause of the scarring has been common in the medical community.

The new study has shown that in patients with COVID-19 who developed heart failure, the virus infects the heart and specifically infects heart muscle cells. Researchers also found that cellular death and loss of heart muscle fibers could happen even in the absence of inflammation. Another interesting finding is that the virus causes a different immune response in the heart than other viruses. Typical viruses that infect the heart cause T cells and B cells to proliferate. However, COVID-19 causes macrophages, monocytes, and dendritic cells to dominate the immune response. Researchers say they don't yet understand what that means.