The COVID-19 pandemic, heart and cardiovascular diseases: What we have learned

In 2020, the coronavirus disease 2019 (COVID-19) pandemic overwhelmed the world, temporarily paralyzing healthcare and economic systems. Until now, we have learned a lot about the symptoms, pathophysiology, and complications of the disease as well as about the laboratory findings concerning the disease, and we are rapidly acquiring new data on the influence of COVID-19 on other aspects of human health beside its effects on the respiratory system. Patients with co-existing cardiovascular diseases (CVD) are more frequently hospitalized, more likely to be treated in an intensive care unit (ICU) and have poorer prognoses. In this article, we discuss the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on CVD, starting from the mechanisms connected with the renin-angiotensin-aldosterone system (RAAS) and the angiotensin-converting enzyme 2 (ACE2) receptors, and then describing the main pathologies in the heart and vessels detected in patients with COVID-19. Additionally, we comment on the problem of acute coronary syndrome (ACS), which may be triggered by viral infection. Finally, we discuss how, in some countries, the pandemic has changed treatment patterns, lowering the rate of invasive diagnostics and even falsely reducing the prevalence of CVD as a result of patients' fear of being admitted to hospital.