Coronavirus disease of 2019 (COVID-19) is a disease caused by the novel coronavirus SARS-CoV-2, which is characterized by a multitude of clinical abnormalities, including hypercoagulability. Although thrombosis is commonly observed in sepsis, the hypercoagulable state associated with COVID-19 is much more dramatic and may not be related to either the severity of the disease or the D-dimer levels. It may be due to a prothrombotic state induced by the disease itself. We report three cases of arterial thrombosis with a significant clot burden requiring urgent medical and surgical intervention. It is now a common practice to initiate anticoagulation for deep venous thrombosis (DVT) prophylaxis based on the D-dimer level in hospitalized patients with COVID-19. However, in our clinical experience, D-dimer levels did not correlate well with the clot burden or the risk for future thrombosis.