Left ventricular thrombosis (LVT) is one of the most feared complications of both ischemic and non-ischemic cardiopathy, and despite its incidence having decreased over the years (mostly due to novel reperfusion therapies in acute coronary syndromes), it is still not negligible. If transthoracic echocardiography, possibly with the adjunction of echo contrast, represents the cornerstone in LVT diagnosis, sometimes it is found to be nonconclusive and advanced cardiovascular imaging, namely cardiac magnetic resonance, needs to be performed to fully exclude intraventricular masses or to better characterize them. Vitamin K antagonists always represented the anticoagulant of choice for the treatment of LVT; however, the recent spread of direct oral anticoagulants (DOACs) pushed clinicians to adopt them also in this setting despite the absence of robust evidence in their favor. If the optimal duration of anticoagulation for the treatment of LVT in non-ischemic cardiopathy is still a matter of debate, an initial treatment of 3–6 months seems to be reasonable in the setting of ischemic cardiopathy, with possible extension according to the follow-up findings. High-quality randomized studies are strongly needed to evaluate the potential role of prophylactic anticoagulation in high-risk patients and provide conclusive evidence for the use of DOACs in LVT treatment.

Pericardial effusion can result from multiple causes, and patients with Down syndrome are at increased risk. We report a case of idiopathic pericardial effusion in a Down syndrome patient, highlighting ECG as an important diagnostic feature for timely and effective management of this condition.