The most commonly understood danger is to the lungs, as patients suffering form severe instances of Covid-19 undergo a form of life-threatening pneumonia. But a study published in the journal JAMA Cardiology at the end of March found that 1 in 5 patients were noted as suffering heart damage from their fight against the virus. In fact, Covid-19 appears to have caused heart damage even in patients with no prior history of heart disease.
A number of explanations have been proposed for this. One is that the virus might be attacking heart cells directly – but this is yet to be proven conclusively.
A second proposed explanation is that by attacking the lungs and inhibiting the body's supply of oxygen, it may be imposing great strain on the heart as it struggles to pump blood through the body.
A third possibility is that the patient's fierce immune system response to the virus, which is responsible for a lot of other damaging symptoms, could also be affecting the heart. The International Journal of Cardiology describes this process as “overwhelming immune inflammatory response and cytokine storm”.
The journal JAMA Cardiology noted that even in influenza epidemics, heart damage causes more deaths than the actual pneumonia itself. The International Journal of Cardiology also notes:
“There is also some data to suggest that patients with underlying heart disease may be more susceptible to contracting coronavirus infection.”