Case Presentation: An unvaccinated 56-year-old man with a past medical history of hypertension, insulin dependent diabetes, sleep apnea, and obesity presented to the emergency department with complaints of dyspnea, cough, fevers, and diarrhea for the past 5 days. Initial work up was significant for COVID-19, a normal troponin level, elevated inflammatory markers, creatinine of 1.57, a sodium of 121, a normal B-type Natriuretic Peptide, nonischemic electrocardiogram and a chest X-ray consistent with COVID-19 pneumonia. He was started on protocolized Dexamethasone and Remdesivir as well as daily subcutaneous low molecular weight heparin (LMWH). He later developed paroxysmal atrial fibrillation and was started on a heparin infusion. Within twelve days of admission, he required intubation due to worsening hypoxia. A transthoracic echocardiogram was concerning for a 1.8cm by 1.1cm apical LVT with normal EF and wall motion. A Heparin PF4 antibody was normal, ruling out heparin induced thrombocytopenia and thrombosis. Patient course was complicated by seizure like activity and a subacute moderately sized middle cerebral artery infarct. Heparin infusion was continued due to further stroke burden risk outweighing hemorrhagic conversion. Eventually, our patient ultimately perished due to shock and hypoxia.

Discussion: The differential for intracardiac mass includes thrombus, tumor, and vegetation. This mass was less likely a tumor due to its location or a typical vegetation with normal blood cultures. Further elucidation would require advanced imaging like transesophageal echocardiography, cardiac magnetic resonance imaging and use of gadolinium. None of these were performed in our patient due to his poor prognosis. LVT formation is most associated with left anterior descending artery MI with wall motion abnormality and systolic dysfunction. There have been cases with normal ventricular function associated with malignancy, inflammatory conditions such as ulcerative colitis and rheumatoid arthritis, blood dyscrasias like essential thrombocythemia, lupus anticoagulant, and exogenous causes such as tamoxifen or cocaine use. It is possible that our patient had one of these conditions undiagnosed, but he did not have a history of coagulopathic events.

Conclusions: Left ventricular thrombus (LVT) formation is not an uncommon phenomenon in the setting of reduced ejection fraction (EF) due to myocardial infarction (MI) or significant cardiomyopathy. However, there are less than 50 reported cases of LVT with normal EF and wall motion. Furthermore, there have been many cases of LVT associated with COVID-19 and abnormal left ventricles, this is a novel case involving normal ventricular function. Presumably this LVT formation was driven by hypercoagulability from COVID-19, a hotly discussed topic since the advent of the pandemic. Currently, the European Society of Cardiology recommends typical dosing of LMWH for thromboprophylaxis. The American Society of Hematology makes a similar recommendation but recognizes that this might change for different patient populations. This case occurred in September 2021, when the Delta Variant was the most common strain, and raises questions concerning the virulence of this strain in atypical ways.