Chronic Cardiac Herniation: A Peculiar Diagnosis.

The presented case describes a 56-year-old male with adult-onset Still's disease, exhibiting polyserositis in 2019, who underwent pleurectomy and pericardiectomy. Despite treatment with tocilizumab and methylprednisolone, the patient developed deep vein thrombosis and pulmonary embolism in 2022, managed with apixaban. A contrast-enhanced chest tomography revealed no recurrent thromboembolic events. Over a year, the patient experienced progressive dyspnea, correlating with signs of constriction on transthoracic echocardiogram. Cardiac magnetic resonance imaging confirmed cardiac herniation, prompting pericardiectomy. Surgery led to complete resolution of anatomical alterations without heart failure or new abnormalities, although exertional dyspnea persists post-discharge. The pathophysiology of cardiac herniation involves complex mechanisms influenced by congenital or acquired factors, resulting in abnormal heart protrusion. Medical literature highlights varied presentations, with acute cases typically post-thoracic surgeries, while late-onset cases are less common. Imaging modalities like computed tomography (CT) and cardiac magnetic resonance (CMR) aid diagnosis, emphasizing interdisciplinary collaboration. Despite challenges posed by its rarity, timely diagnosis and treatment are crucial for favourable outcomes, demonstrating the importance of considering this entity in clinical practice.