In this report. we present a five-month-old female patient with a diagnosis of idiopathic pulmonary arterial hypertension (IPAH). This patient was accepted by our clinic after a sudden deterioration in her clinical condition. We performed echocardiography and observed a 17 mm pericardial fluid near the left ventricle posterior wall. https://www.foldlyers.shop/product-category/computer-books/