Inflammatory Pericardial Effusion With Hemorrhagic Conversion in Takotsubo Cardiomyopathy.

BACKGROUND: Takotsubo cardiomyopathy (TC) is a reversible stress-induced cardiomyopathy that may be triggered by acute neurologic events. Significant pericardial effusions associated with TC are uncommon, and hemorrhagic transformation is rarely reported. CASE SUMMARY: A 75-year-old woman developed TC after an ischemic stroke and was started on dual antiplatelet therapy (DAPT). Initial transthoracic echocardiogram demonstrated a small pericardial effusion. Six weeks later, she was incidentally found to have a large hemorrhagic pericardial effusion with echocardiographic features of tamponade requiring pericardiocentesis and ultimately a pericardial window. Extensive evaluation for infectious, malignant, and autoimmune etiologies was unrevealing. DISCUSSION: This case highlights a rare progression from TC-associated inflammatory pericardial effusion to a hemorrhagic effusion in the setting of recent DAPT exposure and underscores the complex interaction between neurocardiac stress and bleeding risk. TC may generate an inflammatory milieu involving the pericardium and pleura, increasing the risk of effusions and influencing management, particularly with antithrombotic therapy. TAKE-HOME MESSAGES: TC after acute neurologic injury can be complicated by evolving pericardial effusions that may rarely become hemorrhagic. In patients receiving DAPT, close surveillance may be warranted, as antithrombotic exposure may potentiate clinically significant pericardial bleeding.