Coronavirus (Covid-19) and the heart: Lingering damage for an uncertain number of patients

“The family of seven known human coronaviruses are known for their impact on the respiratory tract, not the heart,” Dr. Eric Topol of the Scripps Research Translational Institute writes in Science. “However, the most recent coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has marked tropism for the heart and can lead to myocarditis (inflammation of the heart), necrosis of its cells, mimicking of a heart attack, arrhythmias, and acute or protracted heart failure (muscle dysfunction). These complications, which at times are the only features of coronavirus disease 2019 (COVID-19) clinical presentation, have occurred even in cases with mild symptoms and in people who did not experience any symptoms. Recent findings of heart involvement in young athletes, including sudden death, have raised concerns about the current limits of our knowledge and potentially high risk and occult prevalence of COVID-19 heart manifestations. The four ‘common cold’ human coronaviruses—HCoV-229E, HCoV-NL63, HCoV-OC43, and HCoV-HKU1—have not been associated with heart abnormalities. There were isolated reports of patients with Middle East respiratory syndrome (MERS; caused by MERS-CoV) with myocarditis and a limited number of case series of cardiac disease in patients with SARS (caused by SARS-CoV). Therefore, a distinct feature of SARS-CoV-2 is its more extensive cardiac involvement, which may also be a consequence of the pandemic and the exposure of tens of millions of people to the virus. … The virus targets the angiotensin-converting enzyme 2 (ACE2) receptor throughout the body, facilitating cell entry by way of its spike protein, along with the cooperation of the cellular serine protease transmembrane protease serine 2 (TMPRSS2), heparan sulfate, and other proteases (3). The heart is one of the many organs with high expression of ACE2. Moreover, the affinity of SARS-CoV-2 to ACE2 is significantly greater than that of SARS. The tropism to other organs beyond the lungs has been studied from autopsy specimens: SARS-CoV-2 genomic RNA was highest in the lungs, but the heart, kidney, and liver also showed substantial amounts, and copies of the virus were detected in the heart from 16 of 22 patients who died (5). In an autopsy series of 39 patients dying from COVID-19, the virus was not detectable in the myocardium in 38% of patients, whereas 31% had a high viral load above 1000 copies in the heart. Accordingly, SARS-CoV-2 infection can damage the heart both directly and indirectly.” Eric Topol, “Covid-19 can affect the heart,” Science.